Medicinal and Aromatic Plants - Fenugreek: The Genus Trigonella

Fenugreek
© 2002 Georgios A. Petropoulos

Volume 1
Valerian
Edited by Peter J. Houghton
Volume 2
Perilla
Edited by He-ci Yu, Kenichi Kosuna and Megumi Haga
Volume 3
Poppy
Edited by Jenö Bernáth
Volume 4
Cannabis
Edited by David T. Brown
Volume 5
Neem
Edited by H.S. Puri
Volume 6
Ergot
Edited by Vladimír Kr˘en and Ladislav Cvak
Volume 7
Caraway
Edited by Éva Németh
Volume 8
Saffron
Edited by Moshe Negbi
Volume 9
Tea Tree
Edited by Ian Southwell and Robert Lowe
Volume 10
Basil
Edited by Raimo Hiltunen and Yvonne Holm
Volume 11
Fenugreek
Edited by Georgios A. Petropoulos
Medicinal and Aromatic Plants – Industrial Profiles
Individual volumes in this series provide both industry and academia with in-depth coverage of
one major medicinal or aromatic plant of industrial importance.
Edited by Roland Hardman

Fenugreek
The genus Trigonella
Edited by
Georgios A. Petropoulos
London and New York

First published 2002
by Taylor & Francis
11 New Fetter Lane, London EC4P 4EE
Simultaneously published in the USA and Canada
by Taylor & Francis Inc,
29 West 35th Street, New York, NY 10001
Taylor & Francis is an imprint of the Taylor & Francis Group
All rights reserved. No part of this book may be reprinted or reproduced or utilised in
any form or by any electronic, mechanical, or other means, now known or hereafter
invented, including photocopying and recording, or in any information storage or
retrieval system, without permission in writing from the publishers.
Every effort has been made to ensure that the advice and information in this book
is true and accurate at the time of going to press. However, neither the publisher nor
the authors can accept any legal responsibility or liability for any errors or omissions
that may be made. In the case of drug administration, any medical procedure or the
use of technical equipment mentioned within this book, you are strongly advised to
consult the manufacturer’s guidelines.
British Library Cataloguing in Publication Data
A catalogue record for this book is available from the British Library
Library of Congress Cataloging in Publication Data
Fenugreek: the genus Trigonella / edited by George A. Petropoulos.
p. cm – (Medicinal and aromatic plants – industrial profiles)
ISBN 0-415-29657-9 (hbk.)
1. Fenugreek. I. Petropoulos, George A. II. Series.
SB317 .F44 F45 2002
633.8Ј8—dc21 2002072359
ISBN 0-415-29657-9
This edition published in the Taylor & Francis e-Library, 2003.
ISBN 0-203-21747-0 Master e-book ISBN
ISBN 0-203-27322-2 (Adobe eReader Format)
(Print Edition)

Contents
List of figures vii
List of tables ix
List of contributors xi
Preface to the series xii
Preface xiv
Acknowledgments xvi
1 Introduction 1
GEORGIOS A. PETROPOULOS
2 Botany 9
GEORGIOS A. PETROPOULOS AND PANAGIOTIS KOULOUMBIS
3 Physiology 18
CAROLINE G. SPYROPOULOS
4 Cultivation 26
5 Breeding 73
6 Nutrition and use of fertilizers 103
PANAGIOTIS KOULOUMBIS
7 Pests and diseases 120
GEORGE MANICAS
8 Weeds 128
C.N. GIANNOPOLITIS
9 Chemical constituents 132
HELEN SKALTSA
10 Pharmacological properties 162
MOLHAM AL-HABORI AND AMALA RAMAN
11 Marketing 183
CHRISTOS V. FOTOPOULOS

Figures
3.1 ␣-Galactosidase and endo-␤-mannanase activities in the endosperms
of fenugreek seeds and the dry weight of six extracted endosperms ϩ
testa at several imbibition times 20
4.1 Multistock and monostock plants of fenugreek, due to the corresponding
low and high plant density (1ϭmonostock, 2ϭmultistock) 29
4.2 Relationship between earliness of sowing and earliness of flowering and
consequently of maturity (based on sowing in mid-May) 30
4.3 A typical nodule of Rhizobium meliloti 2012 on fenugreek 31
4.4 Small and scattered ineffective nodules over secondary roots of fenugreek 32
4.5 Degree of nodulation of fenugreek plants with Rhizobium meliloti 2012
in (a) virgin and (b) non virgin soil 33
4.6 Effect of nodulation with Rhizobium meliloti 2012 on seed yield of
fenugreek plants 34
4.7 Prolonged period of seed germination of Moroccan and especially of
Kenyan cultivar of fenugreek, due to their higher percentage of hard seeds 36
4.8 Relationship between scarification time by concentrated sulphuric acid and
percentage of fenugreek seed germination, with optimum time in 35–40min 37
4.9 The first growth habit of a fenugreek seedling 38
4.10 ‘Blind’ shoot of fenugreek with axillary and terminal flower 39
4.11 The different parts of the corolla of a fenugreek flower 40
4.12 The relative position of the stamens and pistil of a fenugreek flower 41
4.13 A ‘cleistogamous’ (closed) flower of fenugreek, that favours self-pollination 41
4.14 An ‘aneictogamous’ (open) flower of fenugreek, that favours cross-pollination 42
4.15 Diagram of the four stages of development in a fenugreek flower 43
4.16 Twin pods on the top of the fenugreek mutant plant RH 3112 44
4.17 The different parts of a fenugreek seed 45
4.18 Rectangular (down) and round (upper) shape of fenugreek seeds 46
4.19 Leaves of four breeding cultivars of fenugreek 51
4.20 Seeds of four breeding cultivars of fenugreek 52
4.21 Chromatogram of fenugreek seeds of four breeding cultivars, showing
the presence of only one colour spot in the Fluorescent cultivar 53
5.1 The lower position of the pistil in comparison to the stamens, after the half
part of the second stage of a cleistogamous flower of fenugreek, that enables
the free deposition of pollen on the stigma, favouring self-pollination 75
5.2 Difference in four characters between colorata and pallida type plants
of fenugreek 78

viii List of figures
5.3 A radiation device (installation) with the special raising mechanism
for irradiating the source, in operation 81
5.4 The same device with the special mechanism to lower the source into
its protective lead shield, during visits to the experimental area 81
5.5 Orbitic sowing of the field irradiation area 1m apart 82
5.6 Amount of irradiation received by the fenugreek plants according to
their distance from the center of the source 83
5.7 Amount of irradiation received by the reproductive organs of the fenugreek
plants, according to their distance from the center of the source 84
5.8 Correlation between seed irradiation dose with acute gamma rays and
flowering days of fenugreek 85
5.9 Correlation between seed irradiation dose with acute gamma rays and
height of fenugreek plants 86
5.10 Reduction in height of fenugreek plants, due to seed irradiation with
acute gamma rays 87
5.11 Correlation between seed yield and seed irradiation dose with acute
gamma rays 87
5.12 Reduction in root length of fenugreek plants, due to seed irradiation
with acute gamma rays 88
5.13 Correlation between protein content of fenugreek seed and the number
of favourable phenotypes of plant to this direction 92
5.14 Susceptibility of Moroccan cultivar of fenugreek to attacks by the fungus
Oidiopsis sp. 95
5.15 Aphid and mechanical transmission of BYMV to fenugreek plants 96
6.1 Leaves of different fenugreek cultivars with symptoms of
mineral deficiencies 108
6.2 Boron deficiency symptoms in a hybrid fenugreek plant
(FluorescentϫKenyan) 111
6.3 Manganese deficiency symptoms on a fenugreek plant of the Ethiopian
cultivar 114
7.1 Fenugreek leaves covered by different diseases 123
7.2 Fenugreek plants affected by the fungus Ascochyta sp., where the leaves
have died and fallen 124
7.3 Dark brown and black spots of the fungus Heterosporium sp., spread on
the surface of the fenugreek pods 125
9.1 Chemical structures of sapogenins 133
9.2 Chemical structures of asparasaponin I and compound XII 136
9.3 Chemical structures of trigofoenosides A, D, F, G 137
9.4 Chemical structures of trigofoenosides B, C, E 138
9.5 Chemical structures of trigoneosides Ia, IIa, IIIa 138
9.6 Chemical structures of trigoneosides Ib, IIb, IIIb 139
9.7 Chemical structures of trigoneosides IVa, Va, Vb, VI, VIIb, VIIIb 140
9.8 Chemical structures of trigoneosides Xa, Xb, XIb, XIIa, XIIb, XIIIa 142
9.9 Chemical structures of glycoside D, glycoside F and compound C 144
9.10 Chemical structures of commonly encountered Isoflavonoid
Phytoalexins in Trigonella species 151
10.1 Putative anti-diabetic or hypocholesterolaemic compounds
in fenugreek seeds 163
11.1 The structure of the spice industry 186

Tables
2.1 A list of the well known species of the genus Trigonella 10
2.2 Natural or local names of fenugreek, in different countries 15
3.1 ␣-Galactosidase activity and galactomannan levels in endosperms of
fenugreek seeds after 48h of imbibition, following the excision of
the axis after 5h 21
3.2 ␣-Galactosidase and endo-␤-mannanase activity of leached or non-leached
endosperms that were isolated from 5-h-imbibed seeds and incubated
in water, in the endosperm ϩ testa leachate or in PEG, for 20h 22
4.1 Determination of the water requirements for seed germination among four
breeding cultivars of fenugreek 35
4.2 Determination of the hardness of fenugreek seeds due to the drying conditions 36
4.3 List of the most used varieties of cultivars of fenugreek in the world 49
4.4 Agronomical and chemical evaluation of four breeding cultivars 52
4.5 Theoretical seed yield of four breeding cultivars, based on seed yield
components by UK conditions 54
4.6 List of some promising genotypes of fenugreek 54
4.7 Yield components for different varieties and various environmental conditions 62
4.8 Recapitulation of the reported therapeutical properties of fenugreek 66
4.9 Human and animal diseases or disorders that have been reported as cured
by using fenugreek, as a remedy 67
5.1 List of ten morphological characters of fenugreek, for which the way of
inheritance has been investigated 77
5.2 Sensitivity of four breeding cultivars of fenugreek to attacks by three
different pathogens 95
5.3 Precocity of four breeding cultivars of fenugreek 98
5.4 Resistance to lodging of four breeding cultivars of fenugreek 98
6.1 Proportion of main nutrients removed by fenugreek hay 105
6.2 Amount of nutrients removed annually by the production of fenugreek hay/ha 105
6.3 Amount of nutrients removed annually by the edible portion of fenugreek
seed production/ha 105
6.4 Analysis of plant nutrients in fenugreek stalks and empty pods 106
6.5 Boron deficiency symptoms for four fenugreek cultivars 110
6.6 Magnesium (Mg) deficiency symptoms in four fenugreek breeding cultivars 112
6.7 Manganese (Mn) deficiency symptoms on four fenugreek breeding cultivars 113
7.1 The main pest enemies reported to attack fenugreek plants 120
7.2 The major diseases reported to attack plants of
certain species of the genus Trigonella 122

x List of tables
10.1 Summary of the reported anti-diabetic properties of fenugreek in vivo 165
10.2 Summary of the reported hypocholesterolaemic and hypolipidaemic
effects of fenugreek in vivo 170
11.1 Area production and export of fenugreek from India 188
11.2 Fenugreek spice exports from India during 1991–2 to 1995–6 188

Contributors
Molham Al-Habori, Faculty of Medicine and Health Sciences, University of Sana’a, Sana’a,
Republik of Yemen.
Christos V. Fotopoulos, National Agricultural Research Foundation (NAgReF), 4
Micropoulou str. 14121 N. Iraklio, Athens, Greece.
C.N. Giannopolitis, Benaki Phytopathological Institute, Weed Science Department, Greece.
Panagiotis Kouloumbis, National Agricultural Research Foundation (NAgReF), Athens Soil
Science Institute, Greece.
George Manicas, 32, Analipseos str., 15235 Vrilissia, Greece.
Georgios A. Petropoulos, 4, Antiopis str., 173 43 Athens, Greece.
Amala Raman, King’s College London, Department of Pharmacy, United Kingdom.
Helen Skaltsa, School of Pharmacy, Department of Pharmacognosy and Chemistry of Natural
Compounds, University of Athens, Panepistimiopolis, Zografou, GR-15771, Athens, Greece.
Caroline G. Spyropoulos, University of Athens, Department of Biology, Institute of General
Botany, Athens, Greece.

Preface to the series
There is increasing interest in industry, academia and the health sciences in medicinal and
aromatic plants. In passing from plant production to the eventual product used by the public,
many sciences are involved. This series brings together information which is currently scattered
through an ever increasing number of journals. Each volume gives an in-depth look at one plant
genus, about which an area specialist has assembled information ranging from the production of
the plant to market trends and quality control.
Many industries are involved such as forestry, agriculture, chemical, food, flavour, beverage,
pharmaceutical, cosmetic and fragrance. The plant raw materials are roots, rhizomes, bulbs,
leaves, stems, barks, wood, flowers, fruits and seeds. These yield gums, resins, essential (volatile)
oils, fixed oils, waxes, juices, extracts and spices for medicinal and aromatic purposes. All these
commodities are traded worldwide. A dealer’s market report for an item may say ‘Drought in the
country of origin has forced up prices’.
Natural products do not mean safe products and account of this has to be taken by the above
industries, which are subject to regulation. For example, a number of plants which are approved
for use in medicine must not be used in cosmetic products.
The assessment of safe to use starts with the harvested plant material which has to
comply with an official monograph. This may require absence of, or prescribed limits of,
radioactive material, heavy metals, aflatoxin, pesticide residue, as well as the required level of
active principle. This analytical control is costly and tends to exclude small batches of
plant material. Large scale contracted mechanized cultivation with designated seed or plantlets
is now preferable.
Today, plant selection is not only for the yield of active principle, but for the plant’s ability to
overcome disease, climatic stress and the hazards caused by mankind. Such methods as in vitro
fertilization, meristem cultures and somatic embryogenesis are used. The transfer of sections of
DNA is giving rise to controversy in the case of some end-uses of the plant material.
Some suppliers of plant raw material are now able to certify that they are supplying organically-
farmed medicinal plants, herbs and spices. The Economic Union directive (CVO/EU No 2092/
91) details the specifications for the obligatory quality controls to be carried out at all stages of
production and processing of organic products.
Fascinating plant folklore and ethnopharmacology leads to medicinal potential. Examples are
the muscle relaxants based on the arrow poison, curare, from species of Chondrodendron, and the
anti-malarials derived from species of Cinchona and Artemisia.The methods of detection of phar-
macological activity have become increasingly reliable and specific, frequently involving
enzymes in bioassays and avoiding the use of laboratory animals. By using bioassay linked frac-
tionation of crude plant juices or extracts, compounds can be specifically targeted which, for

Preface to the series xiii
example, inhibit blood platelet aggregation, or have anti-tumour, or anti-viral, or any other
required activity. With the assistance of robotic devices, all the members of a genus may be
readily screened. However, the plant material must be fully authenticated by a specialist.
The medicinal traditions of ancient civilizations such as those of China and India have a large
armamentaria of plants in their pharmacopoeias which are used throughout South-East Asia.
A similar situation exists in Africa and South America. Thus, a very high percentage of the
World’s population relies on medicinal and aromatic plants for their medicine. Western medi-
cine is also responding. Already in Germany all medical practitioners have to pass an examina-
tion in phytotherapy before being allowed to practise. It is noticeable that throughout Europe
and the USA, medical, pharmacy and health related schools are increasingly offering training in
phytotherapy.
Multinational pharmaceutical companies have become less enamoured of the single
compound magic bullet cure. The high costs of such ventures and the endless competition from
‘me too’ compounds from rival companies often discourage the attempt. Independent phyto-
medicine companies have been very strong in Germany. However, by the end of 1995, eleven
(almost all) had been acquired by the multinational pharmaceutical firms, acknowledging the
lay public’s growing demand for phytomedicines in the Western World.
The business of dietary supplements in the Western World has expanded from the health
store to the pharmacy. Alternative medicine includes plant-based, products. Appropriate mea-
sures to ensure the quality, safety and efficacy of these either already exist or are being answered
by greater legislative control by such bodies as the Food and Drug Administration of the USA
and the recently created European Agency for the Evaluation of Medicinal Products, based in
London.
In the USA, the Dietary Supplement and Health Education Act of 1994 recognized the class
of phytotherapeutic agents derived from medicinal and aromatic plants. Furthermore, under
public pressure, the US Congress set up an Office of Alternative Medicine and this office in 1994
assisted the filing of several Investigational New Drug (IND) applications, required for clinical
trials of some Chinese herbal preparations. The significance of these applications was that each
Chinese preparation involved several plants and yet was handled as a single IND. A demonstra-
tion of the contribution to efficacy, of each ingredient of each plant, was not required. This was
a major step forward towards more sensible regulations in regard to phytomedicines.
My thanks are due to the staffs of Harwood Academic Publishers and Taylor & Francis who
have made this series possible and especially to the volume editors and their chapter contributors
for the authoritative information.
Roland Hardman

Preface
In recent decades increasing attention has been paid in utilization and consumption of natural
and traditional products (foods, flavours, colours, perfumes, phytotherapeutics etc.), because
modern scientific knowledge and technologies have revealed that many chemical products of
synthetic origin of this kind are responsible for a lot of new hazards and disorders for human
beings.
The plant species of the genus Trigonella and especially that of T. foenum-graecum L. (fenugreek)
is a good example, which has been used traditionally to cover such human needs. Fenugreek is
cultivated all over the world and mainly in India and the Mediterranean countries as chemurgic,
cash and good renovator of soil crop and as a multi-purpose legume, is used as forage, food, spice,
perfume, insect repellent, dye, herbal medicine etc.
The biological and pharmaceutical actions of fenugreek are attributed to the variety of its
constituents including steroids (diosgenin), alkaloids (trigonelline), flavonoids (luteolin),
coumarins, aminoacids (hydroxyisoleucine), mucilage (galactomannan), volatile constituents
(HDFM), fixed oils and other substances.
Species of the genus Trigonella and particularly fenugreek are well known for their pungent
aromatic, high nutritive and multi-therapeutical properties and serve culinary, medicinal and
industrial purposes.
As there is today an emerging change in food habits preference for natural colouring, flavour-
ing and revolution in packaging, fenugreek could contribute to this direction, as its seeds are
a component of many curry preparations and are used to colour and flavour food, stimulate
appetite and help digestion.
Fenugreek is one of the oldest known medicinal plants from ancient times and even
Hippocrates thought highly of it. Fenugreek seeds which are described in the Greek and Latin
Pharmacopoeias are said to have anti-diabetic activity and hypocholesterolaemic effects and have
been reported to possess a curative gastric anti-ulcer action and anti-fertility and anti-nociceptive
effects. The therapeutic efficacy of fenugreek extracts in providing sedation has been proved by
many pharmacological and clinical experiments. So, many of its actions as remedy have been
confirmed and the mechanisms of their activity are being studied. Also, some other properties of
fenugreek which have been reported but received less attention include anti-cancer, anti-bacterial,
anthelmintic, anti-cholinergic, wound healing activities, etc.
Fenugreek seed as a source of diosgenin, that is the base for the production of the oral contra-
ceptives and rich in protein and fixed oils, could make a two-fold economic contribution to the
world’s increasing population problems, by assisting in birth control and at the same time, pro-
viding additional food, especially for people, where meatless diets are customary for cultural and
religious reasons.

Preface xv
Finally, it is doubtful if any other plant crop, while saving energy by fixation of atmospheric
nitrogen, has such potential for making a major contribution to the world’s food supply, to
reduce hunger, improve health care and help population control.

Acknowledgments
I would like to thank the numerous people who helped to make this work possible. In
particular I appreciate Dr R. Hardman for his continuous advice and helpful suggestions,
Dr Anthony Dweck, Research Director of Peter Black Toiletries and Cosmetics Ltd. for
providing a data base of references on the use and history of fenugreek and Demetrios Cotarides
for his assistance with the drawings.
Finally I am indebted to my family for their continuous encouragement.

1 2 3
1
2
1 2
3
1 2 3
Mg
Mn
B
P
Color Plate I (See Chapter 6, p. 108. Panagiotis Kouloumbis)
Figure 6.1 Leaves of different fenugreek cultivars with symptoms of mineral deficiencies
(Photo: G. Petropoulos).
Color Plate II (See Chapter 6, p. 111. Panagiotis Kouloumbis)
Figure 6.2 Boron deficiency symptoms in a hybrid fenugreek plant (FluorescentϫKenyan)
Mg 1: Fluorescent
2: Ethiopian
3: Moroccan
Mn 1: Fluorescent
2: Ethiopian
3: Kenyan
B 1: Moroccan
2: Kenyan
P 1: Fluorescent
2: Ethiopian
3: Kenyan

Color Plate III (See Chapter 6, p. 114. Panagiotis Kouloumbis)
Figure 6.3 Manganese deficiency symptoms on a fenugreek plant of the Ethiopian cultivar
1
3 4
6
5
2
1: Heterosporium sp. in
Fluorescent cultivar.
2: Heterosporium sp. in
Ethiopian cultivar.
3: Oidiopsis sp. in Moroccan
cultivar.
4: Oidiopsis sp. in Kenyan
cultivar.
5: Oidiopsis sp. in Ethiopian
cultivar.
6: Leaf miners in Kenyan
cultivar.
Color Plate IV (See Chapter 7, p. 123. George Manicas)
Figure 7.1 Fenugreek leaves covered by different diseases (Photo: G. Petropoulos).

1 Introduction
This introductory chapter deals with a brief analysis of the history, world cultivated area, main
uses, needs for research and future trends of the most important species of the genus Trigonella
and especially that of T. foenum-graecum (fenugreek).
History
Plants of the genus Trigonella and particularly of the cultivated species T. foenum-graecum
(fenugreek) were known and used for different purposes in ancient times, especially in Greece
and Egypt (Rouk and Mangesha, 1963). In North Africa it has been cultivated around the
Saharan oases since very early times (Duke, 1986).
Hidvegi et al. (1984) report that references to the utilization of fenugreek are found as far back
as 1578, when detailed information on the plant is given in the famous Kolozsvar Herbarium
compiled by Melius (1578). In this Transylvanian Herbarium the ‘warming and very drying’
nature of fenugreek and its antique sources are emphasized. Fenugreek seeds were found in the
tomb of Tutankhamun (Manniche, 1989). Portius Cato, a Roman authority on animal hus-
bandry in the second century BC ordered foenum-graecum, that was today’s fenugreek, to be shown
as fodder for oxen (Fazli and Hardman, 1968). Antiochus Epiphanes, King of Syria, and all those
who entered the gymnasium to witness the games were anointed with perfumes from golden
dishes that contained fenugreek and other aromatic plants (Leyel, 1987). Leaves of fenugreek
were one of the components of the celebrated Egyptian Incense Kuphi, a holy smoke used in
fumigation and embalming rites (Rosengarten, 1969). Miller (1969) reports that fenugreek was
a spice plant mentioned in classical texts.
Historically, fenugreek is one of the oldest known medicinal plants and even Hippocrates
thought highly of it (Lust, 1986; Schauenberg and Paris, 1990). There is a prescription for the
rejuvenational properties of fenugreek of Pharaonic date (Manniche, 1989). Fenugreek was first
introduced into Chinese medicine in the Sung dynasty, AD 1057 (Jones, 1989). Dioscorides,
a greek physician of Anazarbus in Cilicia, father of Pharmacology, at AD 65, in his examination
of the definition and function of spices in his Materia Medica, writes that fenugreek is an active
compound of ointments (Miller, 1969). He also describes a concoction of fenugreek seeds to treat
the vulva. In the seventeenth century fenugreek seeds were recommended to help expel the
placenta of women after giving birth (Howard, 1987). The herb has long been a favourite of the
Arabs and it was studied at the School of Salermo by Arab physicians (Stuart, 1986). Fenugreek
was known and cultivated as forage in ancient Greece. Theophrastus had given it the greek
names Bo␷␬␧Ј␳␣␵ (Voukeras) and T␩Ј␭␫␵ (Tilis) and the oil produced from it was called t␩Ј␭␫o␯
␧Ј␭␣␫o␯ (oil of Tilis). Probably fenugreek is one of the forages known to have been cultivated
before the era of recorded history. As a fodder plant, it is said to be the Hedysarum of

Theophrastus and Dioscorides (Leyel, 1987). Dioscorides also says that the Egyptians called it
‘itasin’ (Manniche, 1989). In the Middle Ages it is recorded that fenugreek was added to inferior
hay, because of its peculiar pleasant smell (Howard, 1987).
Fenugreek was introduced into Central Europe at the start of the ninth century (Schauenberg
and Paris, 1990), according to Fazli and Hardman (1968) Charlemagne encouraged its cultiva-
tion in this area. Rosengarten (1969) reports that the Romans obtained the plant from the
Greeks, and that it became a commercial commodity of the Roman Empire (Miller, 1969), while
Stuart (1986) and Howard (1987) support the contention that Benedictine monks introduced
the plant into medieval Europe. However, it is not mentioned in any herbal literature until the
sixteenth century, when it was recorded as grown in England.
Cultivated area
Furry (1950) describes five cultivated species of the genus Trigonella as: T. foenum-graecum,
T. caerulea, T. polycerata, T. monspeliaca and T. suavissima, while in Flora European (Ivimey-Cook,
1968) only two species to be cultivated are reported: T. foenum-graecum and T. caerulea; the last
one has also been reported as cultivated by Uphof (1968). However, statistics of the cultivated
area for forage and seed production are not available, except for the T. foenum-graecum (fenugreek).
Fenugreek has been reported as a cultivated crop in Portugal, Spain, United Kingdom,
Germany, Austria, Switzerland, Greece, Turkey, Egypt, Sudan, Ethiopia, Kenya, Tanzania,
Israel, Lebanon, Morocco, Tunisia, India, Pakistan, China, Japan, Russia, Argentine and the
United States of America (Rouk and Mangesha, 1963; Fazli and Hardman, 1968; Rosengarten,
1969). At the present time fenugreek is an important cash crop in India (the leading fenugreek
producing country), Morocco, China, Pakistan, Spain, Tunisia, Turkey, Lebanon, Israel, Egypt,
Ethiopia, Kenya, Tanzania etc. (Smith, 1982; Edison, 1995).
As far as the world cultivated area of fenugreek and the annual production of seed are
concerned, statistics are very limited and scattered, as the area seeded with fenugreek is rela-
tively small and not recorded by the agricultural statistics of different countries. In spite of this,
the following analysis based on the exported quantities of the principal producing countries, the
domestic use of fenugreek and the existing statistics of the cultivated area for some countries,
represents a reasonably accurate assessment of the world production and cultivated area of
fenugreek.
So, taking into consideration that:
1 The cultivated area of fenugreek in India, an average for the last twenty years
(1975–95), accounts for 34,534 ha with a production of 41,530 tons and an export of
4203 tons, that is domestic use accounts for 90 per cent of the production (Anonymous,
1996).
2 Recently, there has been an increase in the export of fenugreek from India: in 1994–95 it
accounted for 7,956 tons (Anonymous, 1996). According to Edison (1995) India claims
70–80 per cent of the world export in fenugreek. This means that the world export of
fenugreek until 1995 fluctuated around 10,500 tons, and export from the other countries
mentioned above can be estimated as approaching 2,700 tons. According to the fore-
mentioned considerations, the cultivated area from these countries accounts for about
22,000 ha with a production of 26,700 tons.
3 These considerations permit us to estimate that in the world, the annually cultivated area of
fenugreek amounts to roughly 57,000 ha with a seed production of 68,000 tons.
2 Georgios A. Petropoulos

The wide distribution of fenugreek is indicated by the large number of names that it has in
several languages, with Arabic, Indian, Sanskrit, Greek and Latin roots. It has many local names
(see Chapter 2).
Uses
Almost all the species of the genus Trigonella are strongly scented (Anonymous, 1994) and most
of them are used as insect repellent (Chopra et al., 1949; Duke, 1986) for the protection of
grains, cloths, etc.; while the essential oils of some of them are a very valuable raw material for
the perfumery (Fazli and Hardman, 1968).
Most of these species (T. foenum-graecum, T. caerulea, T. corniculata, T. hamosa, T. balansae,
T. laciniata, T. marginata, T. occulta, T. anguina, T. arabica, T. glabra, T. stelata, T. coerulenses,
T. spinosa, T. sibthorpii, T. spicata, etc.) are rich in protein, vitamins and amino acids (Hidvegi
et al., 1984), while the seeds and the fresh material are used as forage, especially for cattle,
mainly in the eastern Mediterranean area. In particulars T. arabica and T. stelata are foraged by
animals in the desert areas of the Sahara, Palestine and the Dead Sea (Allen and Allen, 1981).
Several species of Trigonella (T. foenum-graecum, T. balansae, T. corniculata, T. maritima, T. spicata,
T. coerulea, T. occulta, T. polycerata, T. calliceras, T. cretica, etc.) contain some interesting, from the
pharmaceutical point of view, phytochemical compounds belonging to steroids, flavonoids and
alkaloids (Anonymous, 1994) and efforts are being made to use some of them as a source of these
constituents, especially of the steroidal diosgenin (Hardman, 1969). Seeds of these species also
yield choline, a semicrystalline white saponin, a lactation-stimulating oil and various gums
(Allen and Allen, 1981).
The alkaloid trigonelline has been isolated from plant parts, mainly seeds of T. caerulea, T. cretica,
T. foenum-graecum, T. lilacina, T. radiata, T. spinosa (Allen and Allen, 1981) and T. polycerata
(Mehra et al., 1996). This pyridine alkaloid is known for its hypoglycemic and hypocholesterolaimic
properties (Mehra et al., 1996).
Some of these species are also used in traditional as well as veterinary medicine for different
diseases, alone or in combination with other remedies: T. occulta, T. polycerata and T. uncata are
included among the Indian herbals along with T. foenum-graecum (Hardman and Fazli, 1972).
The well developed endosperm of most of the species is rich in the polysaccharide mucilage
(galactomannan) that has wide uses in industry including in pharmaceuticals and cosmetics.
In some parts of Pakistan and India T. corniculata is used for different purposes: its young tops
are currently used as a green vegetable, the dried herb as a flavouring agent and its seeds for the
treatment of swellings and bruises (Hardman and Fazli, 1972).
Chopped foliage of the species T. caerulea (sweet trefoil) is used in Switzerland for flavouring
green cheeses: Schabzieger, Chapsiger and Serred Vert. In some parts of Tirol sweet trefoil is used for
flavouring the bread called Brotwn
rze. Sweet trefoil is also employed as a condiment in soups and
potatoes, as a decoction for tea, and as flavouring in Chinese tea (Allen and Allen, 1981).
Hardman and Fazli (1972) report that in Switzerland sweet trefoil has also been used in herbal
medicine.
The varied and numerous special uses of the species T. foenum-graecum (fenugreek) are
described in more detail in Chapter 4.
Need for research
This section reports on T. foenum-graecum (fenugreek), which is the only widely cultivated species
of the genus Trigonella.
Introduction 3

Fenugreek faces problems that keep it from reaching its full potential. Recently Edison
(1995) reported that in India there are problems in improving the productivity of spices, one of
which is fenugreek, due to:
G lack of advanced breeding methods for creation of high yielding varieties
G inherent inability expressed through poor and slow germination
G lack of adequate genetic variability
G lack of research based on crop rotation and cropping system
G inadequate techniques for diagnostic tests and screening for host resistance
G poor methods of nutrition and general management, particularly in light and sandy
soils
G lack of incentives for seed production and poor storage facilities
G inadequate production and delivery systems of high quality planting material
G lack of facilitation of import genetic material for evolving new and improved varieties.
In order to overcome these problems, the following strategies have been under consideration
(Edison, 1995):
G investigation of yield and loss forecasting models for both the producer and the trader
G import/exchange of valuable germplasm and promising varieties from the main regions of
the Mediterranean in order to overcome the yield barrier
G production, distribution and delivery guaranteed planting material (certified seeds)
G identification on the basis of region suitable variety and choosing the best one together with
the package of practices
G organization of demonstration fields
G motivating farmers to apply improved management techniques
G organizing cooperative markets and conducting producer–buyer–trader meetings in
respective centres.
In India, in the last fifty years, eight research and development plans have been established
for spices, including fenugreek, through a wide network of research institutions and state
universities under the All India Coordinated Research Project (A.I.C.R.P, Edison, 1995).
Similar problems are faced by fenugreek growers in other fenugreek producing countries
throughout the world. Further, the necessary research information is not available to help them
make correct decisions regarding existing problems.
It is a safe assumption, however, that all these problems can be solved by approaches through
a well planned research programme taking into consideration the research priorities for
fenugreek.
Projections must relate to comparative high yields, lower production costs, development of
improved and better adapted varieties characterized by higher quantity and better quality, inves-
tigation of technological changes in production and utilization techniques and development of
improved management practices; in general, fenugreek is grown under poor management
conditions (Paroda and Karwasra, 1975).
A significant increase in yields through the suitable use of irrigation and adequate levels of
soil fertility could make an immediate and important contribution to farm income. The very
high yields recorded under experimental conditions (Petropoulos, 1973; Evans, 1989) and the
reported big differences in seed yield among twenty-nine ecotypes (Banyai, 1973) suggest that it
is not taking full advantage of the yield capacity of many fenugreek varieties.

Production cost is increasing and research must help the farmer, so that the money invested in
increasing crop yields is reflected in the amount and the quality of collected seed or forage.
Adaptable and improved genotypes and varieties are needed, suitable for: mechanization, no
scattering of seed, high yielding and seed content characterized by high active constituents
(diosgenin, protein etc., Cornish et al., 1983), resistant to diseases, pests and drought. However,
fenugreek is generally considered an unpretentious plant and rarely subject to diseases and pests
(Sinskaya, 1961; Hardman, 1969; Duke, 1986).
The creation of a genotype without the peculiar smell that causes the tainting of animal prod-
ucts (milk, meat) and its derivatives (Molfino, 1947; Talelis, 1967) for an unlimited parallel use
as forage for better valorization of the crop, should be another research objective. This objective
should be based on the condition that progress in this goal is not offset by losses in some other
valuable crop attributes.
There is also a need for research in the investigation and adaptation of new, more rapid and
accurate analytical methods, for isolation and characterization of steroids, for analysis and uti-
lization of the flavour extracts, the nutritive value of protein, the bread making ability of seed,
and in general for the analysis and utilization of the other active constituents of fenugreek. The
increase of the diosgenin content during the growing period through fertilization (Kozlowski
et al., 1982), use of herbicides (Mohamed, 1983) and other cultivation methods, as well as post
harvest treatments through fermentation (Evans, 1989), incubation (Elujoba and Hardman,
1985), enzymes (Elujoba and Hardman, 1987), hormonal influence (Hardman and Stevens,
1978), tissue culture (Stevens and Hardman, 1974) and other biotechnological methods are
some of the other critical areas.
The identification of the mechanisms of fenugreek galactomannan biosynthesis (during seed
development) and hydrolysis (during germination) in order to produce transformed fenugreek
plants, where the ratio Gal./Man. is appropriate for industrial use (Reid and Meier, 1970; Li
et al., 1980), needs further research efforts. The complete mechanization of sowing, harvesting,
threshing and cleaning of fenugreek seed to increase yields and reduce the cost of production
are also critical areas for research. This will help scientists to develop, through integrated
research management programmes, means to establish optimum levels of fenugreek production
and to optimize the yield of active constituents per unit area for a wide range of environmental
and other conditions and for specific farming situations.
Future trends
The usefulness of fenugreek as a commercial and chemurgic crop is now being recognized, not
only as a break-crop for cereal areas, where it is a very good soil renovator (Duke, 1986), but as
forage, medicinal plant, source of diosgenin (the most important raw material for the steroid
industry) and other constituents (protein, fixed oils, mucilage), as well as for culinary uses: as a
traditional and modern flavouring.
Fenugreek is grown in about 57,000 ha with a production of 68,000 tons. Higher seed yield
per hectare will be obtained through superior varieties and better management practices and
may contribute to an increase in the crop worldwide; however, in India during the eighth plan of
research and development, the overall growth rate of spices, including fenugreek, was 8 per cent.
Fenugreek with the other spices, is a major source of foreign exchange for India (Edison, 1995).
From the world production of fenugreek it can be estimated that more than half is produced
in India. India consumes domestically 90 per cent of its own production and claims 70–80
per cent of the world exports in fenugreek (Edison, 1995). Although the market for fenugreek
is considerably small, there is a world incremental growth rate in demand of 4 per cent
Introduction 5

and a steady increase in exports as recently reported by Edison (1995), who is the key-man for
spices of India and especially for fenugreek seeds, and later by an anonymous study (1996).
It is obvious that all this information on the characteristics and cultivation of fenugreek, like
other specific crop plants, cannot serve as the sole basis for predicting immediate and long-term
trends. But it is believed that the following facts, which have been noticed during the last years,
open new prospects that could presage changes in farm practices that will affect positively the
future of fenugreek production, especially in traditional fenugreek producing countries:
1 As recently reported by Edison (1995) there is an emerging change in food habits, preference
for natural colouring and flavouring in fast food restaurants chains, microwave cooking,
revolution in packaging and demand for quality assurance in relation to ISO 9000. It has
been estimated that these changes will increase the world demand for spices, including
fenugreek. Its exports from India increased in 1995–96, more than two-fold on an average
over the last three years, reaching the amount of 15,135 tons (Anonymous, 1996). This
increase in combination with the recently signed Uruguay Round Agreements for spice
marketing (Nandakumar, 1997) will create new prospects for its cultivation.
2 One possible application, for which it is claimed fenugreek has good prospects, is its
utilization as source of diosgenin, a steroidal precursor. Diosgenin is of importance to the
pharmaceutical industry as a starting material in the partial synthesis of corticosteroids, sex
hormones and oral contraceptives. At present, natural diosgenin is obtained mainly from
the tubers of certain wild species of Dioscorea in Mexico, a process that is costly and difficult,
requiring several years before the tubers grow to a size with significant content of dios-
genin. On the other hand fenugreek is an unpretentious plant (Sinskaya, 1961; Hardman,
1969) and gives a consistent seed yield in a short growing period. The extraction of dios-
genin from fenugreek may become attractive as today’s widely used synthetic diosgenin will
be implicated for some side-effects. But this extraction must be economically viable not
through a fall in the price, but by the increase of its diosgenin content with genetic,
agronomic and biotechnological methods and by reduction of the cost production, in such a
manner that it will be attractive and be able to offer more prospects to growers.
3 The recent investigation of a technical development involving the spraying of liquid
flavours of fenugreek on foodstuffs is claimed to give a better flavour dispersion than the
usual method of simply sprinkling the dry flavour compound on the feed (Smith, 1982) and
because of this the demand for fenugreek will increase rapidly. It is well known that the
fenugreek flavour extract for animal feed, for both ruminants and pigs, is the main reason
for fenugreek seed exports in the United Kingdom and other European countries (Smith,
1982).
4 The preparation of bread from fenugreek for those suffering from diabetes is ideal. It has
less starch and polysaccharides are present in the form of silico-phosphoric ester of
manogalactan, which is not hydrolyzed by ptyalin or pancreatic amylase (Kamel, 1932),
and fenugreek seeds have an insulin stimulating substance (Hillaire-Buys et al., 1993), plus
a high protein content. This could be combined with the confirmed results during the last
years of anti-diabetic (Sharma et al., 1996) and anti-hypercholestrolaimic (Khosla et al.,
1995) effect of fenugreek seeds. This use is expected to seriously increase the consumption
of fenugreek seed and to create better prospects for this crop in the future.
5 Due to the increasing protein deficiency all over the world, considerable efforts are
being made to discover the nutritional potential of neglected sources. Thus, the aim now
and even more in the future, is to utilize every protein source wherever and however it will
have the highest nutritional value. Fenugreek protein is rich in lysine (345 mg gϪ1
) and in

comparison to the data for human requirements its quality, calculated from the amino-acid
pattern, approaches that of the soybean (Hidvegi et al., 1984). Therefore, it is an important
crop for those countries in the Middle and Far East where meatless diets are customary for
cultural and religious reasons.
The conclusion drawn is that the future of fenugreek is promising and its seed, as a source of
diosgenin, which is the base for the production of oral contraceptives and rich in protein and
fixed oils, could make a two-fold economic contribution to the world increase of population
problems by assisting in birth control and at the same time providing additional food. The obvi-
ous growth in human population, due mainly to the increase in average life expectancy in the
world because of the reduction in infant mortality, the progress in medicine and the improve-
ment of food and residence conditions, results in pressures for human foods that will increase
continuously. Fenugreek will have an important role to play, as many countries, especially in
Asia and Africa, have fantastic opportunities to increase its production with no serious inroads
on their supplies of cereal grains, for which fenugreek is a very good soil renovator (Duke, 1986).
Therefore, population growth control can be achieved, further on a planet where the human pop-
ulation consumes the total production from every acre of tillable land additional food will be
obtained.
References
Allen, O.N. and Allen, E.K. (1981) The Leguminosae, Macmillan Co., London.
Anonymous (1994) Plants and Their Constituents, Phytochemical Dictionary of the Leguminosae, Vol. 1, Cherman
and Hall, London.
Anonymous (1996) Spices Statistics, Spices Board, Ministry of Commerce, Governement of India, P.B.
No. 2277, Cochin.
Banyai, L. (1973) Botanical and qualitative studies on ecotypes of fenugreek (Trigonella foenum-graecum L.).
Agrobotanica, 15, 175–87.
Chopra, R.N., Badhwar, R.L. and Ghosh, S. (1965) Poisonous Plants of India, Vol. 1, Indian Council of
Agricultural Research, New Delhi.
Cornish, M.A., Hardman, R. and Sadler, R.M. (1983) Hybridization for genetic improvement in the yield
of diosgenin from fenugreek seed. Planta Medica, 48, 149–52.
Duke, A.J. (1986) Handbook of Legumes of World Economic Importance, Plemus Press, New York and London.
Edison, S. (1995) Spices – research support to productivity. In N. Ravi (ed.), The Hindu Survey of Indian
Agriculture, Kasturi & Sons Ltd., National Press, Madras, pp. 101–5.
Elujoba, A.A. and Hardman, R. (1985) Incubation conditions for fenugreek whole seed. Planta Medica,
51(2), 113–15.
Elujoba, A.A. and Hardman, R. (1987) Saponin hydrolyzing enzymes from fenugreek seed. Fitoterapia,
58(3), 197–9.
Evans, W.C. (1989) Trease and Evans Pharmacognosy, 13th edn, Balliere Tindall, London.
Fazli, F.R.Y. and Hardman, R. (1968) The spice fenugreek (Trigonella foenum-graecum L.). Its commercial
varieties of seed as a source of diosgenin. Trop. Sci., 10, 66–78.
Furry, A. (1950) Les cahiers de la recherche agronomique. 3, 25–317.
Hardman, R. (1969) Pharmaceutical products from plant steroids. Trop. Sci., 11, 196–222.
Hardman, R. and Fazli, F.R.Y. (1972) Methods of screening the genus Trigonella for steroidal sapogenin.
Planta Medica, 21, 131–8.
Hardman, R. and Stevens, R.G. (1978) The influence of N.A.A. and 2,4 D on the steroidal fractions of
Trigonella foenum-graecum static cultures. Planta Medica, 34, 414–19.
Hidvegi, M., El-Kady, A., Lásztity, R., Bekes, F. and Simon-Sarkadi, L. (1984) Contribution to the
nutritional characterization of fenugreek (Trigonella foenum-graecum L.). Acta Alimentaria, 13(4), 315–24.
Introduction 7

Hillaire-Buys, D., Petit, P., Manteghetti, M., Baissac, Y., Sauvaire, Y. and Ribes, G. (1993) A recently
identified substance extracted from fenugreek seeds, stimulates insulin secretion in rat. Diabetologia, 36,
A 119.
Howard, M. (1987) Traditional Folk Remedies, A Comprehensive Herbal, Century Hutchinson Ltd., London.
Ivimey-Cook, R.B. (1968) Trigonella L. In T.G. Tutin, V.H. Heywood, N.A. Burges, D.M. Moore, D.H.
Valentine, S.M. Walters, and D.A. Webb (eds), Flora Europaea – Rosaceae to Umbelliferae, Cambridge
University Press, Cambridge 2, 150–2.
Jones, C.P. (1989) Extracts from Nature, Marks and Spencer P.L.C., Tigerprint, London.
Kamel, M.D. (1932) Reserve polysaccharide of the seeds of fenugreek. Its digestibility and its fat during
germination. Biochem. J., 26, 255–63.
Khosla, P., Gupta, D.D. and Nagpal, R.K. (1995) Effect of Trigonella foenum-graecum (fenugreek) on serum
lipids in normal and diabetic rats. Indian J. Pharmacol., 27, 89–93.
Kozlowski, J., Nowak, A. and Krajewska, A. (1982) Effects of fertilizer rates and ratios on the mucilage
value and diosgenin yield of fenugreek. Herba Polonica, 28(3–4), 159–70.
Leyel, C.F. (1987) Elixirs of Life, Faber & Faber, London.
Li, X., Farn, M.-J., Feng, L.-B., Shan, X.-Q. and Feng, Y.-H. (1980) Analysis of the galactomannan gums
in 24 seeds of Leguminosae. Chin. Wu, Hsueh Pao, 22(3), 302–4.
Lust, J.B. (1986) The Herb Book, Bantam Books Inc., New York.
Manniche, L. (1989) An Ancient Egyptian Herbal, British Museum Publ. Ltd., London.
Mehra, P., Yadar, R. and Kamal, R. (1996) Influence of nicotinic acid on production of trigonelline from
Trigonella polycerata tissue culture. Indian J. Experim. Biol., 34(11), 1147–9.
Melius, P. (1578) Herbarium, Heltai Gásparne Könyvnyomdája, Kolozsvár.
Miller, J.I. (1969) The Spice Trade of the Roman Empire 29 B.C. to A.D. 641, Clarendon Press, Oxford.
Mohamed, E.S.S. (1983) Herbicides in Fenugreek (Trigonella foenum-graecum L.) with Particular Reference to
Diosgenin and Protein Yields, PhD Thesis, Bath University, England.
Molfino, R.H. (1947) Argentine plants producing changes in the characteristics of milk and its derivatives.
Rev. Farm. (Buenos Aires), 89, 7–17.
Nandakumar, T. (1997) International spice marketing and the Uruguay Round Agreements. International
Trade Forum, 1, 18–27.
Paroda, R.S. and Karwasra, R.R. (1975) Prediction through genotype environment interactions in
fenugreek. Forage Res., 1(1), 31–9.
Petropoulos, G.A. (1973) Agronomic, genetic and chemical studies of Trigonella foenum-graecum L., PhD. Thesis,
Bath University, England.
Reid, J.S.G. and Meier, H. (1970) Chemotaxonomic aspects of the reserve galactomannan in leguminous
seeds. Z. Pflanzenphysiol., 62, 89–92.
Rosengarten, F. (1969) The Book of Spices, Livingston, Wynnewood, Penns., USA.
Rouk, H.F. and Mangesha, H. (1963) Fenugreek (Trigonella foenum-graecum L.). Its relationship, geography and
economic importance, Exper. Stat. Bull. No. 20, Imper. Ethiopian College of Agric. & Mech. Arts.
Schauenberg, P. and Paris, F. (1990) Guide to Medicinal Plants, Lutterworth Press, Cambridge, UK
Sharma, R.D., Sarkar, A., Hazra, D.K., Misra, I., Singh, J.B. and Maheshwari, B.B. (1996) Toxicological
evaluation fenugreek seeds: a long term feeding experiment in diabetic patients. Phytotherapy Research,
10(6), 519–20.
Sinskaya, E. (1961) Flora of cultivated plants of the U.S.S.R. XIII. Perennial leguminous plants, Part I. Medic,
Sweet clover, Fenugreek, Israel Programme for Scientific Translations, Jerusalem.
Smith, A. (1982) Selected Markets for Turmeric, Coriander, Cumin and Fenugreek seed and Curry Powder, Tropical
Product Institute, Publication No. G 165, London.
Stevens, R.G. and Hardman, R. (1974) Steroid studies with tissue cultures of Trigonella foenum-graecum L.
using G.L.C. Proc. 3rd Intern. Congress of Plant Tissue and Cell Culture, Leicester, 1974.
Stuart, M. (1986) The Encyclopaedia of Herbs and Herbalism, Orbis, London.
Talelis, D. (1967) Cultivation of Legumes, Agric. College of Athens, Athens (in greek).
Uphof, J.C.T. (1968) Dictionary of Economic Plants, Lehre Verlag von J. Cramer, New York.

2 Botany
Georgios A. Petropoulos and Panagiotis Kouloumbis
The genus Trigonella
Taxonomy
The genus Trigonella according to Hutchinson (1964) is one of the six genera (the other five
are: Parochetus, Melilotus, Factorovekya, Medicago and Trifolium) of the Subfamily or Tribe
Trifoliae of the Family Fabaceae (Papilionaceae) within the order Leguminosae (Leguminales).
Several investigators have attempted to employ the taxonomy of the genus Trigonella. Sirjaev
(1933) has given in Latin an elaborate and systematic account of its taxonomy. Vasil’chenko
(1953) has published a synopsis in Russian discussing the position of the genus within the
Family Leguminosae and gave keys, synonyms and descriptions of the morphological characters of
different series, their economic importance and geographical distribution. Hutchinson (1964),
Heywood (1967) and Sinskaya (1961) have also given detailed descriptions of its taxonomic
characters. According to these authors, the genus Trigonella contains mostly annual or perennial
plants that are often strongly scented, and are described in the following terms.
Leaves pinnately 3-foliate; stipules adulate to the petiole; leaflets usually toothed and nerves
often running out into teeth; flowers solitary or sessile or pedunculate in axillary heads or in
short racemes; calyx teeth equal or unequal; corolla yellow, blue or purplish, free from the
staminal tube or with wings united with prongs at the keel. Keel obtuse, shorter than the
wings; stamens diadelphous or monadelphous with filaments not broadened; anthers uniform;
stigma terminal; ovary sessile, ovules numerous. Pods varying greatly in size, cylindrical or com-
pressed, linear or oblong, straight or curved, indehiscent or dehiscing with a pronounced short
or long mucro (beak). Seeds, 1-many, finely or fairly markedly tuberculate, smooth; cotyledodns
geniculate.
There is a big controversy about the number of species that comprise the genus
Trigonella. Two hundred and sixty (260) species (182 from Linnaeus to 1885 and 78 from 1886
to 1965) are listed under this genus, but a close scrutiny reveals about ninety-seven distinct
species (Fazli, 1967), while Vasil’chenko (1953) has described 128 species. Hector (1936),
Kavadas (1956), Rouk and Mangesha (1963) and Hutchinson (1964), have reported about
seventy.
The most interesting species of the genus Trigonella are presented in Table 2.1.
The reference to Index Kewensis (Hocker and Jackson, 1955) shows that much synonymity
has occurred within the species of the genus Trigonella, that is, as has been reported in the section
on Fenugreek, three different species have been described as T. foenum-graecum.

10 Georgios A. Petropoulos and Panagiotis Kouloumbis
Table 2.1 A list of the well known species of the genus Trigonellaa
T. anguina Del. T. marginata Hochst. & Steud.
T. arabica Del. T. maritima Poiret or Delile ex Poiret in Lam.
T. arcuata C.A. Mey T. melilotus caeruleus (L.) Ascherson & Graebnerc
T. aristata Vass. T. monantha C.A. Mey
T. auradiaca Boiss. (ϭ T. aurantiaca Boiss.) T. monspeliaca L. (ϭT. monspeliana L.)d
T. balansae Boiss. and Reut. in Boiss. T. no␦ana Boiss.
(ϭT. corniculata L.) T. occulta Ser. Del.
T. berythaea Boiss. and Blanche T. ornithopoides (L.) DC.e
T. brachycarpa (Fisch) Moris T. orthoceras Kar. & Kir.
T. caelesyriaca Boiss. T. pamirica Gross. in Kom.
T. caerulea (L.) Ser. (ϭT. coerulea L.) T. platycarpos L.
T. calliceras Fisch ex Bieb. T. polycerata L.
T. cancellata Dest. T. popovii Kor.
T. cariensis Boiss. T. procumbens (Besser) Reichenb.
T. coerulescens (Bieb.) Halacsy Hal. T. radiata Boiss.
T. corniculata (L.) L. (ϭT. balansae T. rechingeri Sirj.
Boiss. & Reut.) T. rigida Boiss. & Bal.
T. cretica (L.) Boiss.b
T. ruthenica L.
T. cylindracea Desv. (ϭT. culindracea Desv.) T. schlumbergeri Buser (Boiss.)
T. emodi Benth. T. sibthorpii Boiss.
T. erata T. smyrnaea Boiss.
T. fischeriana Ser. T. spicata Sibth. an Sm. (ϭT. homosa Bess.)
T. foenum-graecum L. T. spinosa L.
T. geminiflora Bunge T. sprunerana Boiss. (ϭT. spruneriana Boiss.)
T. gladiata Stev. or Stev. ex Bieb. (ϭT. tortulosa Gris.)
T. graeca (Boiss. and Spruner) Boiss. T. stellata Forssk.
T. grandiflora Bunge T. striata L.
T. hamosa L. T. suavissima Lindl.
T. hybrida Pourr. T. tenuis Fisch ex Bieb.
T. incisa Benth. T. tortulosa Gris. (ϭT. sprunerana or spruneriana Boiss.)
T. kotschyi Fenzl. ex Boiss. T. uncata Boiss. & Noe. (ϭT. glabra subs. uncata
T. laciniata (L.) Desf. (Boiss. & Noe.) Lassen)
T. lilacina Boiss.
Notes
a The botanical names have been completed according to the Index Kewensis (Hocker and Jackson, 1955).
b It has transformed to the genus Melilotus under the name M. creticus.
c It has fused with the species T. caerulea under the name T. caerulea.
d It has transformed to the genus Medicago under the name M. mospeliaca or monspeliana.
e It has transformed to the genus Trifolium under the name T. ornithopoides.
Further, in the Index Kewensis the following thirteen synonyms are given for the genus
Trigonella:
1 Aporathus Broamf. (1856)
2 Botryolotus Jaub (1842)
3 Buceras1
Hall (1785)
4 Falcatula Brot (1801)
5 Foenum-graecum (Tourn) Rupp. (1745)
1 Probably from the Bo␷␬␧Ј␳␣␵ (␤o␷´␵ϭox and K␧Ј␳␣␵ϭhorn) one ancient Greek name that Theophrastus had given
for fenugreek.

6 Follicullicera Pasq. (1867)
7 Grammocarpus Schur. (1853)
8 Kentia Adans (1763)
9 Melisitus Medic (1787)
10 Nephromedia Kostel (1844)
11 Pocockia Ser (1825)
12 Tellis1
Linn.Syst.ed.I (1735)
13 Trifoliastrum Moench (1794)
Some explanation for the assignment, reassignment and regroup of certain species between
the genus Trigonella, Medicago and Melilotus is required. Brenac and Sauvaire (1996) proposed
that pollinastanol and steroidal sapogenins should be used as chemotaxonomic markers to inves-
tigate the generic separation between the three genera. Their results support the unchanged
assignment of T. corniculata, T. caerulea and T. melilotus caeruleus. They confirm the regroup of the
last two species under the name T. caerulea and also the transform of T. monspeliaca to the genus
Medicago. However, their results do not completely support the unchanged assignment of
T. calliceras to the genus Trigonella, nor the reassignment of the T. cretica to Melilotus cretica, as the
composition of this species is close to that of T. foenum-graecum, for the compounds investigated.
The taxonomic transfer of T. ornithopoides (L.) DC. to the genus Trifolium appears justified in the
light of rhizobial kinships (Allen and Allen, 1981). Also, the ratio Gal./Man. of the reserve
galactomannan of the seed possesses a relative chemotaxonomical value as it varies among the
different plant genus of Leguminosae (Reid and Meier, 1970).
According to Darlington and Wylie (1945) the chromosome contents for the genus indicate
a basic haploid number of 8, 9, 11 and 14. Most of the species reported are diploid with 16 chro-
mosomes. However T. homosa from Egypt is reported to have 16 and 44 chromosomes,
T. ornithoides from Europe 18, and T. polycerata from the Mediterranean and South West Asia 28,
30 and 32.
Tutin and Heywood (1964) divide the genus Trigonella into three subgenera, according to the
form and shape of the calyx and pod, as follows:
a Subgenus Trigonella: Calyx usually campanulate. Pod not inflated, with representatives of
the species T. graeca, T. cretica, T. maritima, T. corniculata.
b Subgenus Trifoliastrum: Calyx campanulate. Pod inflated with representatives of the species
T. caerulea and T. procumbes.
c Subgenus Foenum-graecum: Calyx tubular. Pod not inflated with representatives of the
species T. foenum-graecum and T. coerulescens.
Ingham (1981) found that three groups of species occur in Trigonella, based on results of their
ability to release coumarin on tissue maceration. Two of these groups linking the genus
Medicago, Factorovekya and Melilotus and the third group with the genus Trifolium.
Furry (1950) also divided the cultivated species of the genus Trigonella, according to the
colour of the corolla and other characters, as follows:
a Corolla blue: T. caerulea
b Corolla whitish: T. foenum-graecum
c Corolla yellow:
i Plant annual, calyx with teeth equal to the tube: T. polycerata
ii Plant annual, calyx with teeth longer than the tube: T. monspeliaca
iii Plant perennial: T. suavissima
Botany 11

We do not agree completely with the corolla colour of the species T. foenum-graecum reported
above, as in our experiments this colour was yellow from the beginning and for most of the flow-
ering period and only at the end, if at all, did the colour turn whitish.
Distribution
The Mediterranean region is known to be the natural habitat of the genus Trigonella. Species of
the genus exist wild in the countries of Europe, Macaronesia (Canarian Islands) North and South
Africa, Central Asia and Australia (Anonymous, 1994).
Indigenous species of this genus have been reported (Anonymous, 1994): six for Asia
(T. caelesyriaca, T. calliceras, T. emodi, T. geminiflora, T. glabra, T. kotschyi), five for Europe
(T. graeca, T. striata, T. polycerata, T. monspeliaca, T. procumbens), one for Africa (T. laciniata) and
one for Australia (T. suavissima), where it has adapted well to the wet swampy habitat (Allen and
Allen, 1981). The rest of the species exist in more than one continent, that is, twenty-three
species of this genus have been reported for Europe (Ivimey-Cook, 1968), of which fifteen occur
in the Balkan area (Polunin, 1988) including the fourteen for Greece (Kavadas, 1956), of which
four occur in the famous Island Kefallinia (Phitos and Damboldt, 1985).
However, the most interesting species of the genus is the widely cultivated T. foenum-graecum
(fenugreek), which is described in detail.
Fenugreek (T. foenum-graecum L.)
Taxonomy
According to Sinskaya (1961), Hutchinson (1964), Tutin and Heywood (1964) and our
observations the chief taxonomic characters of the species T. foenum-graecum are the
following.
Stems 20–130 cm long, straight, rarely ascending, branching, rarely simple, sparsely
pubescent, usually hollow, anthocyanin tinged at base or all the way up, rarely completely green.
First leaf simple, some times weak trifoliate, oval or orbicular with entire margin and a long
petiole. Stipules fairly large, covered with soft hair. Leaf petiole thickened at the top, attenuate
beyond point of attachment of lateral leaflets. Petiolules very small cartilaginous. Petioles and
petiolules vested on the underside with simple, soft sparse hairs. Leaflets from ovate-orbicular to
oblong-lanceolate, 1–4 cm long, almost equal, finely haired, dentate, near the apex, dentation
more strongly developed in upper than in lower leaves. The petioles and the blades of the leaflets
are anthocyanin-tinged to a varying degree of green. Flowers in leaf axils, mostly twin, more
rarely solitary (we distinguished the cleistogamy and aneictogamy type of flowers). Calyx
6–8 mm, soft hairy with teeth as long as the tube, half as long as the corolla. Corolla 13–19 mm
long pale yellow (white at the end of flowering period), some times lilac coloured at the base.
Standard tend backwards oblong emarginate at apex with bluish spots (these spots are absent
from some genotypes), wings half as long as the standard; keel obtuse, split at base. Pods with
the mucro (beak), 10–18 cm long and 3.5 ϫ5 cm broad, curved, rarely straight, with transient
hairs. Before ripening the pod is green or reddish coloured; when ripe light straw or brown con-
taining 10–20 seeds.
Seeds vary from rectangular to rounded in outline with a deep groove between the radicle
and cotyledons, the length is 3.5–6 mm and the width 2.5–4 mm, light greyish, brown, olive
green or cinnamon coloured, with a pronounced radicle that is half the length of the cotyledons.

The minute hilum lies partly obscured with a deep notch. Odour characteristic. Chromosome
number, 2n ϭ 16.
Linnaeus (1737, 1753) have described the species T. foenum-graecum first. The botanical names
and synonyms assigned to fenugreek according to the Index Kewensis (Hocker and Jackson,
1955) are as follows:
1 Foenum-graecum Linn. sp. pl. 777 Eur. oriens
2 Foenum-graecum (Tourn) Rupp. FL, Jen. Ed. Hall 263 (1745)
3 Graeca St. Lag. in Ann. Soc. Bot. Lyon VII (1880)
4 Hausknechtii (Siry) in obs. T. foenum-graecum var. Hausknechtii (1933)
5 Tibetana (Alef) in obs. T. foenum-graecum officinale var. tibetanum
6 Rhodantha (Alef) in obs. T. foenum-graecum officinale var. rhodanthus
Mathé (1975) gives the following synonyms for the species T. foenum-graecum (L.):
1 Buceras foenum-graecum (L.) All.
2 Foenum-graecum sativum Medik.
3 Foenum-graecum officinale Moench.
4 Foenum-graecum officinale ssp. cultum Alef.
5 Folliculigera graveolens Pasq.
6 Medicago foenu-graeca Ehz Krause.
7 Telis foenum-graecum (L.) O.ktze.
8 Trigonella graeca St.Lag. non Boiss.
9 Trigonella ensifera Trautv.
Hocker and Jackson (1955) also report three different species of Trigonella as having been
described as T. foenum-graecum:
1 The species T. gladiata (Hall) Desc. 138
2 The species T. cariensis Sibth and Sm. Fl. Graec.VIII 48ϩ 766
3 The species T. monspeliaca Suter, Fl. Helv. ed. Hegetachw. II 149
Serpukhova (1934) on the basis of N.I. Vavilev’s collection of fenugreek in Yemen
and Abyssinia, divided the cultivated fenugreek by its whole plant characters into two
subspecies:
a T. foenum-graecum L. ssp. iemensis (referring to the Yemen), which she established, with short
stems and flowers, entire marginate leaflets, lanceolate and short calyx teeth, erect standard
with dots, dried corolla at base of pod, short and lanceolate pod, small number of leaves and
short vegetation period.
b T. foenum-graecum L. ssp. culta (Alefeld) Gams, which had been first noted by Fluckiger and
Hanbury (1879), characterized by taller plants, with dentate leaflets, long flowers, subulate
and long calyx teeth, reflexed and without dots standard, at end of break dried corolla, long
and linear pod, many leaves and long vegetation period.
Serpukhova (1934) also showed the polymorphic character of fenugreek and studied its
variability in detail.
Botany 13

Sinskaya (1961) divided T. foenum-graecum into series, subseries and ecotypes based upon the
taxonomical characters of the plant and gave an account of the morphological characters and
habits of each subspecies and ecotypes.
Also, fenugreek plants have been distinguished in pallida and colorata type and described in
detail (Petropoulos, 1973).
Moschini (1958) divided the cultivated fenugreek in Italy into three ecotypes:
i Sicilian, characterized by high precocity and high yield
ii Toscanian, late in maturity, resistant to cold and high yielding
iii Moroccan, with high precocity, resistant to cold and low yielding
Serpukhova (1934) classified the seeds of T. foenum-graecum according to their shape, size and
colour and distinguished three groups (Indicae, Anatolicae and Aethiopicae), with one variety for
the groups Indicae (nano-fulva) and Anatolicae (magno-fulva) and six varieties for the group
Aethiopicae (fulva, punctato-fulva, olivacea, punctato-olivacea, leucosperma and griseo-
coerulescens), while Fazli and Hardman (1968) give one version of her classification. Sinskaya
(1961) later confirmed Serpukhova’s classification, although he preferred to use the term ‘forms’
rather than ‘varieties’.
Furry (1950) also divides fenugreek seeds into six types (Yemenese, Transcaucasian, African,
Afghan, Chinese-Persian and Indian) and gives details only for the African type, in which
he distinguishes two varieties (North African and Sudanese-Egyptian of Kharthoum).
The seeds of a rich collection of fenugreek samples (more than 300) of Bath University, origi-
nated from the countries of its cultivation, by a careful examination of their general appearance
and other characteristics and in association with the country of origin, can be classified into the
following four types (Petropoulos, 1973):
1 Fluorescent type: Seeds fluorescent under UV light, absence of any pigment in its seed coat,
large (5–6 ϫ3–4 mm) rounded in outline, with high, one thousand seed weight (27–32g)
and Germ./Husk. index, probably induced by spontaneous mutation from Ethiopian popu-
lations, as most of its characters are controlled by recessive genes, not described previously.
It is easily identified. Representatives of this type are the breeding cultivar Fluorescent and
the variety ‘Barbara’.
2 Ethiopian type: Non fluorescent under UV light, moderate in size (4.0–4.5 ϫ3.0–3.5 mm)
with at least four different pigments in its seed coat and a thousand seed weight 22–25g. It
is a natural mixture of Serpukhova’s olivacea and punctato-olivacea. In this type belong
most of the samples from Ethiopia and its neighbouring fenugreek producing countries. It
is a uniform type and very easily distinguished. Representatives of this type are the seeds of
the Ethiopian breeding cultivar.
3 Indian type: Non fluorescent under UV light, with at least four pigments in its seed coat,
very small seeds (2.5–3.5 ϫ2.0–2.5 mm), rectangular in outline, nano-fulva according to
Serpukhova’s classification, a thousand seed weight 15–20g. In this type belong most of the
samples from India, Pakistan, China and Kenya, the latter being bigger than the rest. This
is also a uniform type and very easily distinguished. Representatives of this type are the
seeds of the Kenyan breeding cultivar.
4 Mediterranean type: Non fluorescent under UV light. Large seeds (4.5–6.0 ϫ3.5–5.0 mm),
rectangular in outline, a thousand seed weight 25–31g, a natural mixture of magno-fulva,
fulva and punctato-fulva according to Serpukhova’s classification. In this type belong sam-
ples from Israel where magno-fulva was dominant, from Morocco, Portugal, Spain and

France where the punctato-fulva was dominant and from Greece and Turkey where the fulva
was dominant. It is the least uniform and is not easily identified. Representative of this type
are seeds of the Moroccan breeding cultivar.
Distribution and vernacular names
The species T. foenum-graecum, wild or cultivated, is widely distributed throughout the world, as
is indicated by the great number of names it possesses with Arabic, Indian (Sanskrit) and
European (Greek and Latin) roots. Fenugreek has been reported as a cultivated crop in Portugal,
Spain, United Kingdom, Germany, Austria, Switzerland, Greece, Turkey, Egypt, Sudan,
Ethiopia, Kenya, Tanzania, Israel, Lebanon, Morocco, Tunisia, India, Pakistan, China, Japan,
Russia, Argentine and USA (Rouk and Mangesha, 1963; Fazli and Hardman, 1968;
Rosengarten, 1969; Smith, 1982; Edison, 1995).
The genetic name, Trigonella, comes from Latin meaning ‘little triangle’, in reference to the
triangular shape of the small yellowish-white flowers. The species epithet foenum-graecum means
‘Greek hay’ and according to Rosengarten (1969) the Romans, who got the plant from Greece
where it was a very common crop in ancient times, gave it this name. It is also called ‘ox horn’ or
‘goat horn’ because of the two seed pods projecting in opposite directions usually from the nodes
of the stem base that resemble ox or goat horns.
The main national names for this species are listed in Table 2.2.
Botany 15
Table 2.2 Natural or local names of fenugreek, in different countries
Speaking language of country National or local names of fenugreek
Arabic Hhelbah, Hhelbeh, Hulba, Hulabah
Armenian Shambala
Azerbaijani Khil’be, Boil
Chinese K’u-Tou
Croatic Piskayika, ditelina rogata
Czech Piskayika, recke seno
Dutch Fenegriek
English Fenugreek, fenigrec
Ethiopian Abish
French Fenugrec, Senegre
German Griechisch Heu, Griechisches Heu,
Bockshornklee, Kuhhornklee, Bisamklee
Greek (modern) Trigoniskos (T␳␫␥␻␯␫Ј␴␬o␵), Tsimeni (T␴␫␮␧Ј␯␫),
Tintelis (T␫␯␶␧␭␫Ј␵), Moschositaro (Mo␴␹o␴␫Ј␶␣␳o),
tili (␶␩Ј␭␫), tipilina (␶␩␲␫␭␫Ј␯␣)
Greek (ancient) ␤o␷´␬␧␳␣␵ o ␸␣␳␮␣␬␧␷␶␫␬ó␵, ␶␩Ј␭␫␵
Hungarian Görögszéna
Indian Methi
Italian Fieno greco
Japanese Koroba
Pakistani Methi
Persian (Irani) Schemlit
Polish Fengrek, Kozieradka
Portuguese Alforva
Russian Pazhitnik, Pazsitnyik, Grezsezki szeno
(gr‡c∂skey s‡no)
Slovak Seneyka grecka, seno grecka
Swedish Bockhornsklover
Uzbekistani Khul’ba, Ul’ba, Boidana

References
Allen, O.N. and Allen, E.K. (1981) The Leguminosae, Macmillan Co., London.
Anonymous (1994) Plants and Their Constituents, Phytochemical Dictionary of the Leguminosae, Vol. 1, Cherman
& Hall, London.
Brenac, P. and Sauvaire, Y. (1996) Chemotaxonomic value of sterols and steroidal sapogenins in the genus
Trigonella. Biochem. Systemat. Ecol., 24(2), 157–64.
Darlington, C.D. and Wylie, A.P. (1945) Chromosome Atlas of Flowering Plants, George Allen & Unwin Ltd.,
London.
Edison, S. (1995) Spices – research support to productivity. N. Ravi (ed.), The Hindu Survey of Indian
Agriculture, Kasturi & Sons Ltd., National Press, Madras, pp. 101–5.
Fazli, F.R.Y. (1967) Studies in steroid-yielding plants of the genus Trigonella, PhD Thesis, University of
Nottingham, England.
Fazli, F.R.Y. and Hardman, R. (1968) The spice fenugreek (Trigonella foenum-graecum L). Its commercial
varieties of seed as a source of diosgenin. Trop.Sci., 10, 66–78.
Fluckiger, F.A. and Hanbury, D. (1879) Pharmacographia, Macmillan & Co., London.
Furry, A. (1950) Les cahiers de la recherche agronomique, 3, 25–317.
Hector, J.N. (1936) Introduction to the Botany of Field Crops (Non cereals), Central News Agency Ltd.,
Johannesburg.
Heywood, V.H. (1967) Plant Taxonomy – Studies in Biology No. 5, Edward Arnold Ltd.
Hocker, J.B. and Jackson, D. (1955) Index Kewensis, Tomus II, 1116–1117 (1895) Suppl. XII, 146
(1951–1955), Clarendon Press, Oxford.
Hutchinson, J. (1964) The Genera of Flowering Plants, Vol. 1, Clarendon Press, Oxford.
Ingham, J.L. (1981) Phytoalexin induction and its chemosystematic significance in the genus Trigonella.
Biochem. Systemat. Ecol., 9(4), 275–81.
Ivimey-Cook, R.B. (1968) Trigonella L. In T.G. Tutin, V.H. Heywood, N.A. Burges, D.M. Moore,
D.H. Valentine, S.M. Walters and D.A. Webb (eds), Flora Europaea – Rosaceae to Umbelliferae, Vol. 2,
Cambridge University Press, Cambridge, pp. 150–2.
Kavadas, D.S. (1956) Illustrated Botanical – Phytological Dictionary, Vol. XIII, pp. 3929–33 (in greek).
Linnaeus, C. (1737) General Edition, I, 351, Stockholm.
Linnaeus, C. (1753) Species Plantarum, Silvius, Stockholm, p. 1200.
Máthé, I. (1975) A görögszéna (Trigonella foenum-graecum L.), Magyarország III/2, Kultúrflóra 39, Akadémiai
Kiadó, Budapest.
Moschini, E. (1958) Charatteristiche biologiche e colturali di Trigonella foenum-graecum L. e di Vicia sativa L.
di diversa provenienza. Esperienze e Ricerche, pp. 10–11, Pisa.
Petropoulos, G.A. (1973) Agronomic, genetic and chemical studies of Trigonella foenum-graecum L., PhD. Thesis,
Bath University, England.
Phitos, D. and Damboldt, J. (1985) Die Flora der Insel Kefallinia (Griechenland). Botanika Chronika,
5(1–2), 1–204.
Polunin, O. (1988) Flowers of Greece and the Balkans, A Field Guide, 1.Repr., Oxford University Press,
Oxford, New York.
Reid, J.S.G. and Meier, H. (1970) Chemotaxonomic aspects of the reserve galactomannan in leguminous
seeds. Z. Pflanzenphysiol., 62, 89–92.
Rosengarten, F. (1969) The Book of Spices, Livingston, Wynnewood, Penns., USA.
Rouk, H.F. and Mangesha, H. (1963) Fenugreek (Trigonella foenum-graecum L.). Its relationship,
geography and economic importance, Exper. Stat. Bull. No. 20, Imper. Ethiopian College of Agric. &
Mech. Arts.
Serpukhova, V.I. (1934) Trudy, Prikl. Bot. Genet. i selekcii Sen., 7(1), 69–106 (Russian).
Sinskaya, E. (1961) Flora of Cultivated Plants of the U.S.S.R. XIII, Perennial Leguminous plants, Part I, Medic,
Sweet Clover, Fenugreek, Israel Programme for Scientific Translations, Jerusalem.
Sirjaev, G. (1933) Generis Trigonella L. rivisio critica, Publ. Fac. Sci. Univ. Masaryk Brno, pp. 124–269.

Smith, A. (1982) Selected markets for turmeric, coriander, cumin and fenugreek seed and curry powder, Tropical
Product Institute, Publication No. G165, London.
Tutin, T.G. and Heywood, V.H. (1964) Flora Europaea, Vol. I and II, Cambridge University Press,
Cambridge.
Vasil’chenko, I.T. (1953) Bericht uber die Arten der Gattung. Trigonella Trudy Bot. Inst. Akad. Nauk.
S.S.S.R. 1, 10.
Botany 17

3 Physiology
Caroline G. Spyropoulos
Seed physiology
Seed structure and composition
Although there are as many as seventy-two Trigonella species, most studies on seed structure and
physiology have been performed on the Trigonella foenum-graecum L. (fenugreek).
Fenugreek seeds are surrounded by the seed coat. The seed coat is separated from the embryo by
a well developed endosperm, which is the principal storage organ. In mature seeds the majority of
the endosperm cells are nonliving, the cytoplasmic contents of which are occluded by the store
reserves: galactomannan. This tissue is surrounded by a one cell layer of living tissue: the aleurone
layer. The aleurone layer cells are small and thick walled and contain aleurone grains, which dis-
appear during the course of seed germination (Reid and Meier, 1972; Bewley and Black, 1994).
The role of endosperm galactomannan is dual: it serves as a reserve material that will support
the seedling growth during the early post-germination phase, but also, due to its high water
retention capacity regulates the water balance of the embryo during germination (Reid and
Bewley, 1979).
The embryo, as in all dicotyledons, is composed of a cotyledon pair and the embryo
axis. Apart from the endosperm reserves, there are also reserves in the embryo (proteins, lipids,
sugars) that will be metabolised upon seed germination and will be used for the growth needs of
the young seedling (Bewley et al., 1993).
The fenugreek seed coat apart from its protective character seems also to play a regulatory role
in the mobilisation of the endospermic food reserves (Spyropoulos and Reid, 1985; 1988;
Zambou et al., 1993; Kontos et al., 1996).
Seed development
Seed development starts upon fertilisation of the egg cell in the embryo sac, by one of the male
pollen tube nuclei, and the fusion of the two polar nuclei in the embryo sac with the other pollen
tube nucleus. The result is the formation of the embryo and the endosperm, respectively. The
fenugreek seed development lasts approximately 120 days after anthesis (DAA) (Campbell and
Reid, 1982). Galactomannan accumulation in the endosperm starts approximately 30 DAA and
ends at approximately 55 DAA, just before the seed’s fresh weight starts decreasing (Campbell
and Reid, 1982).
Galactomannan synthesis during seed development: morphology
Galactomannan is deposited as cell wall thickenings of the endosperm cells and its deposition
continues until nearly all the cytoplasm disappears. The only endosperm cells that are not filled

Physiology 19
with galactomannan are the cells of the aleurone layer. In these cells some galactomannan is
deposited only at the outer walls next to the seed coat, at the cell corners, and occasionally at the
side walls (Meier and Reid, 1977).
Galactomannan is deposited first in those cells that are neighbouring the embryo, while in
those next to the aleurone layer, is deposited at the end (Meier and Reid, 1977).
An electron microscopy examination of fenugreek endosperms during the course of galactoman-
nan deposition suggests that galactomannan synthesis takes place in the rough endoplasmic
reticulum, it is accumulated in the netlike enchylema space and released outside the plas-
malemma without the participation of the Golgi apparatus (Meier and Reid, 1977).
Galactomannan synthesis during seed development: biosynthesis
The biochemistry of galactomannan synthesis and mobilisation has attracted much interest,
not only due to its biological importance, but also due to galactomannan extensive application
in industry, notably, food, pharmaceuticals, cosmetics, paper products, paints, plasters, etc.
(Dea and Morrison, 1975; Reid, 1985; Scherbukhin and Anulov, 1999). The ratio of mannose to
galactose varies in the different plant genus but the most appropriate for industry applications
is 4:1. Among the eight Trigonella species studied, all have mannose : galactose ratio approxi-
mately 1:1; only T. erata has a ratio of 1.6 : 1 (Reid and Meier, 1970). Galactomannan biosyn-
thesis has been studied using cell free extracts and whole endosperm tissue (Edwards et al., 1989;
1992).
The synthesis of galactomannan in vivo started about thirty DAA and its deposition increased
until fifty-five DAA. There was a parallel increase in the activities of the mannosyl- and galacto-
syltransferases. The galactomannan present at any time of seed development had a mannose to
galactose ratio of 1:1, the same with that of mature seeds (Edwards et al., 1992).
The enzymes responsible for fenugreek galactomannan biosynthesis were two membrane bound
glycosyltransferases, a GDP-mannose-dependent mannosyltransferase and a UDP-galactose-
dependent galactosyltransferase. The mannosyltransferase catalyses the addition of mannose
residues onto an unknown endogenous primer, which could be galactomannan. The addition of
galactose residues by the action of the galactosyltransferase takes place only on newly transferred
mannose residues on the mannan backbone. The regulation of the mannose to galactose ratio of
the galactomannan by fenugreek is regulated by the enzyme galactosyltranferase (Reid
et al., 1992; 1995). Recently, Edwards et al. (1999) isolated a 51 kDa protein, with galactosyl-
transferase activity and isolated and cloned the corresponding cDNA. This cDNA encodes
a protein, with a single transmembrane ␣-helix near the N terminus, which proved to be
galactosyltransferase.
The mechanisms that underlie fenugreek galactomannan biosynthesis could lead to the
production of transformed fenugreek plants with the required ratio of mannose to galactose
(i.e. 4:1), which is suitable for industrial applications.
Seed germination and endosperm reserve mobilisation
Fenugreek seeds germinated approximately 10h after the start of seed imbibition at 25ЊC in the
dark (Reid and Bewley, 1979; Spyropoulos and Reid, 1985). Endosperm galactomannan mobil-
isation started after about 15 h of imbibition (Reid, 1971; Spyropoulos and Reid, 1985) through
the action of ␣-galactosidase (EC 3.2.1.22), endo-␤-mannanase (EC 3.2.1.78), and exo-␤-
mannanase (EC 3.2.1.25) (Reid et al., 1977; Meier and Reid, 1982; Reid, 1985). The first two
enzymes seem to be synthesised de novo while the third one is present in an active state in the
endosperm of the dry seed. A very low ␣-galactosidase activity was detected in the dry seed,

20 Caroline G. Spyropoulos
which was suggested to be involved in the hydrolysis of the raffinose series oligosaccharides
(Reid and Meier, 1972), while endo-␤-mannanase activity was absent (Reid et al., 1977;
Spyropoulos and Reid, 1988). During the course of seed imbibition the activity of ␣-galactosi-
dase increased. Endo-␤-mannanase activity appeared after 20 h of imbibition and increased
thereafter. The increase of the activities of both hydrolases coincides with the decrease in galac-
tomannan content in the endosperm (Figure 3.1).
The ultimate products of galactomannan hydrolysis, D-galactose and D-mannose, do not accu-
mulate in the endosperm. Both monosaccharides are transported immediately to the embryo by
carriers that have high specificity for the corresponding sugars. These carriers seem to play an
important role in the switching on and off the uptake capacity of these sugars by fenugreek
embryo (Zambou and Spyropoulos, 1989; 1990). The inhibition of galactose uptake by cyclo-
heximide may suggest that the galactose carrier is synthesised de novo during imbibition.
Although galactose and mannose uptake by the embryo is under metabolic control, their uptake
does not take place via a Hϩ
co-transport system. It has been speculated that the metabolic
energy needed for their uptake is used for the phosphorylation of these sugars, thus ensuring
their transformation in cotyledons and consequently the generation of a concentration gradient
between the endosperm and cotyledons.
The disappearance of galactomannan from the embryo is concomitant with the appearance of
transitory starch and high levels of sucrose in the embryo (Reid, 1971; Bewley et al., 1993),
which are formed by the galactomannan hydrolysis products taken up by the embryo. Although
2
0
10 20 30
Time (h)
40 50
4
nkatseed–1
unitsseed–1
6
8
10
20
0
40
mg6seeds–1
60
80
100
8
0
16
24
32
40
Figure 3.1 ␣-Galactosidase (I) and endo-␤-mannanase (G) activities in the endosperms of fenugreek
seeds and the dry weight of six extracted endosperms ϩ testa (N) at several imbibition
times. The dashed line indicates the dry weight of testa, which does not change (Reid
and Bewley, 1979). Decreases in dry weight are due to galactomannan mobilisation
(Spyropoulos and Reid, 1988).

the initiation of starch formation in fenugreek cotyledons is independent of a supply of the
galactomannan hydrolysates in the embryo, their presence is necessary for its accumulation
(Bewley et al., 1993).
There are several factors that regulate galactomannan mobilisation. The prerequisites for its
mobilisation are:
1 The production of the enzymes that hydrolyse galactomannan, that is, ␣-galactosidase and
endo-␤-mannanase.
2 The secretion of these enzymes through the plasmalemma of the aleurone cells and their
diffusion though the aleurone cell wall to reach their site of action.
3 The appropriate conditions for the action of these enzymes in situ.
Galactomannan mobilisation and the production of ␣-galactosidase and endo-␤-mannanase
may take place in isolated endosperms if they are incubated in a large volume under germination
conditions (Reid and Meier, 1972; Spyropoulos and Reid, 1985; Malek and Bewley, 1991). In
contrast, incubation of endosperms in a small volume resulted in the inhibition of ␣-galactosidase
(Table 3.1) (Spyropoulos and Reid, 1985) and endo-␤-mannanase production (Malek and
Bewley, 1991; Kontos et al., 1996). The effect of the small volume incubation medium was
relieved if incubation was preceded by a 2-h-endosperm leaching, suggesting that in the
endosperm and/or seed coat there are leachable inhibitory substances the diffusion of which is
prevented when the volume of the incubation medium is small. Zambou et al. (1993) have iso-
lated three substances from the leachate of fenugreek endosperm and seed coat, which inhibited
the production of ␣-galactosidase by fenugreek endosperm and, chromatographically, behaved
like saponins. These substances, however, did not have any effect on the production of these
hydrolases if endosperms were treated after the start of the galactomannan mobilisation.
Removal of the embryo axis inhibited galactomannan mobilisation and the activity of
␣-galactosidase, suggesting that the embryo axis controlled galactomannan mobilisation. The
effect of embryo axis excision on galactomannan hydrolysis and the activity of ␣-galactosidase
was relieved upon addition of the excised axes into the ‘seed’ incubation medium or incubation
of these ‘seeds’ with benzyladenine (BA) or BA plus GA3 (Table 3.1). Initially, the axis appeared
to have a regulatory function in determining the onset of ␣-galactosidase production in the
endosperm. However, its continuous presence was necessary for the uptake of the galactomannan
hydrolysis products, the accumulation of which inhibited galactomannan breakdown
(Spyropoulos and Reid, 1985; 1988).
Physiology 21
Table 3.1 ␣-Galactosidase activity and galactomannan levels in endosperms of fenugreek
seeds after 48h of imbibition, following the excision of the axis after 5h
Incubated seed part Incubation medium ␣-Galactosidase Galactomannana
(volume ml) nkat seed Ϫ1
mg 6 seedsϪ1
Seed – axis Water (0.5 ml) 0.35 Ϯ0.10 10.6Ϯ1.8
Seed – axis Waterϩexcised axes (0.5ml) 2.30 Ϯ0.13 7.7Ϯ0.7
Seed – axis 10Ϫ5
M BA (0.5ml) 1.86 Ϯ0.37 3.8 Ϯ0.5
Seed – axis 10Ϫ4
M GA3 (0.5ml) 2.02 Ϯ0.15 6.3Ϯ0.4
Note
a Dry weight of six extracted endosperms ϩ testae, less 9.0 mg, the average weight of the testae
(Reid and Bewley, 1979).

Water stress inhibited galactomannan mobilisation. When water stress was imposed on
isolated endosperms before the onset of galactomannan breakdown there was a total inhibition of
the production of ␣-galactosidase and endo-␤-mannanase and consequently galactomannan
hydrolysis did not take place (Table 3.2) (Spyropoulos and Reid, 1988; Zambou et al., 1993;
Kontos et al., 1996). However, if water stress treatment on fenugreek endosperms was preceded
by a 2-h-leaching, the effect of water stress on the production of the two hydrolases was repaired
(Table 3.2) (Spyropoulos and Reid, 1988). These results suggested that under water stress
conditions the removal of the endosperm and seed coat inhibitory substances was prevented.
When water stress was imposed after the start of galactomannan breakdown (on 25-h-
imbibed seeds), although the production of both hydrolases was not affected, galactomannan
breakdown was still inhibited (Spyropoulos and Reid, 1988). The inhibition of galactomannan
breakdown could be attributed to either the inhibition of the galactomannan hydrolases secre-
tion and/or their diffusion through the aleurone cell wall or to the inhibition of ␣-galactosidase
action in situ.
Carob (Ceratonia siliqua) endosperm is a galactomannan reserving tissue (Seiler, 1979;
Spyropoulos and Lambiris, 1980). Water stress imposed on carob endosperm protoplasts did not
affect the production of ␣-galactosidase or endo-␤-mannanase nor their secretion. However,
experiments performed with whole carob endosperms have shown that under water stress con-
ditions, the diffusion of these hydrolases into the endosperm incubation medium was inhibited.
These results suggest that the carob endosperm cell wall controls galactomannan hydrolysis by
the regulation of the diffusion of galactomannan hydrolases to reach the site of their action
(Kontos and Spyropoulos, 1995). Likewise, it could be postulated that water stress affects the
cell wall porosity of the fenugreek aleurone layer resulting in the decreased diffusion of the
galactomannan hydrolysing enzymes.
Under water stress conditions, the amount of galactose taken up by the embryo was reduced
because under these conditions the galactose carrier did not function (Zambou and Spyropoulos,
1990). Therefore, most galactose produced through the action of ␣-galactosidase would remain
in the endosperm. Galactose is a potent inhibitor of ␣-galactosidase and its presence inhibits its
action in situ (Dey and Pridham, 1972). Therefore, although ␣-galactosidase was active, when
water stress was imposed after the start of galactomannan hydrolysis, the presence of galactose in
the endosperm would inhibit its action.
22 Caroline G. Spyropoulos
Table 3.2 ␣-Galactosidase and endo-␤-mannanase activity of
leached or non-leached endosperms that were isolated from
5-h-imbibed seeds and incubated in water, in
the endosperm ϩtesta leachate or in PEG, for 20 h
(Spyropoulos and Reid, 1988; Kontos et al., 1996)
Treatment ␣-Galactosidase Endo-␤-mannanase
nkat seedϪ1
units endospermϪ1
Non-leached→water 8
Leached 2h→water 0.9 14
Leached 2h→leachate 0.15 0.3
Non-leached →PEGa
0.2 2.9
Leached 2h→PEGa
0.7 7.6
Note
a PEG 3350, Ϫ1.5 MPa.

Mobilisation of embryo reserves
The mobilisation of the endosperm and embryo reserves follows a time-dependent pattern that
correlates the metabolic events with one another and with the completion of germination (Leung
et al., 1981). Galactomannan mobilisation started upon radicle protrusion, after about 25h from
seed imbibition. Before the start of galactomannan hydrolysis there is a slight decline in the
embryo free sugars (Reid, 1971). Before germination there is no starch in the fenugreek embryo,
but during galactomannan mobilisation there is a large increase of transient starch in both
cotyledons and axes (Reid, 1971; Bewley et al., 1993). At later times during seed development
the embryo starch is remobilised through the action of ␣-amylase, which has been identified as
a single band on IEF of pI 5.1 (Bewley et al., 1993).
The endosperm galactomannan mobilisation was followed by the mobilisation of embryo
reserves, proteins, lipids and phytate (Leung et al., 1981). Galactomannan hydrolysis was fol-
lowed by the deposition of starch in the embryo. The hydrolysis of cotyledon proteins started
after about 30h from imbibition. At the same time amino acids accumulated in the embryo axis,
while in cotyledons the accumulation of amino acids took place later, suggesting an initial rapid
uptake of the amino acids by the axis. The phytate started declining in cotyledons 50 h from
imbibition and at the same time there was a slight decline in the axis apparently through the
action of phytase, the activity of which started increasing after 40 h of imbibition. This meta-
bolic event was followed by lipid hydrolysis. Lipid content, the majority of which is located
in cotyledons, is approximately 8 per cent of the seed’s dry weight. Concomitant with lipid
hydrolysis was the increased activity of the isocitrate lyase.
Recently, the activities of ␣-galactosidase and endo-␤-mannanase (Giammakis and Spyropoulos,
unpublished data) have been detected in the fenugreek embryo. The activity of ␣-galactosidase
was very low and did not change much during the course of the embryo growth. In contrast,
endo-␤-mannanase activity increased with imbibition time in both cotyledons and axes.
Tissue cultures
Fenugreek tissue and cell cultures have been used for either plant regeneration or for the
production of secondary products of economic interest. Among these products are diosgenin and
trigonelline: a saponin and an alkaloid with therapeutic properties, which are constituents of
fenugreek seeds (Cerdon et al., 1996; Merkli et al., 1997; Oncina et al., 2000).
The development of fenugreek calli has been achieved after shoot or root culture from 4-day-
old seedlings upon culturing on Gamborg’s B-5 modified medium supplemented with hor-
mones. From these calli have been produced cell suspension cultures, the content of which in
trigonelline was appreciably higher than that of the calli (Radwan and Kokate, 1980). Also, for
diosgenin production hair root cultures (Merkli et al., 1997) and cultures from calli, which were
developed from leaves, stems and roots isolated from 30-day-old seedlings, have been established
with Agrobacterium rhizogenes strain A4 (Oncina et al., 2000).
Apart from the production of trigonelline, tissue cultures have been used for T. corniculata
L. (Piring) and T. foenum-graecum L. (Methi) regeneration. In this case, calli were produced using
leaves as explants. The explants were grown on Murashige and Skoog medium supplemented
with casein hydrolysate or coconut milk. The first resulted in an increased number of differenti-
ated organs per callus (Sen and Gupta, 1979).
Regeneration of shoots have also been achieved from fenugreek protoplasts (Xu et al., 1982).
Protoplasts were isolated from the root apices of 48-h-imbibed seeds. The first divisions of root
fenugreek protoplasts were observed after a 3–4 day culture and subsequent divisions gave cell
colonies. However, a culture of these colonies gave only roots.
Physiology 23

Medicinal and Aromatic Plants - Fenugreek: The Genus Trigonella

Medicinal and Aromatic Plants - Fenugreek: The Genus Trigonella

Recommended

Recommended

More Related Content

What's hot

What's hot (19)

Similar to Medicinal and Aromatic Plants - Fenugreek: The Genus Trigonella

Similar to Medicinal and Aromatic Plants - Fenugreek: The Genus Trigonella (20)

Recently uploaded

Recently uploaded (20)

Medicinal and Aromatic Plants - Fenugreek: The Genus Trigonella