Fenugreek: an “old world” crop for the “new world”

Nutritional value, phytochemical composition, and antioxidant potential of Iranian fenugreeks for food applications

Fenugreeks (Trigonella L. spp.), are well-known herbs belonging to the family Fabaceae, whose fresh and dried leaves have nutritional and medicinal value. In the present study, the content of phytochemical traits (essential oil, diosgenin, trigonelline, total phenol, total flavonoid, total saponins, and total tannins), bitterness value, pigments (chlorophyll, carotenoid, β-carotene, and anthocyanin), vitamins (group B vitamins and ascorbic acid), minerals, and antioxidant activity of thirty cultivated populations belonging to ten Trigonella species were evaluated. The species and populations were significantly different in all studied parameters. A significant positive and negative correlation (p < 0.05) was also observed between the studied parameters. In total, T. teheranica, T. elliptica, and T. foenum-graecum were distinguished as superior species. The results showed that fenugreeks leaves can be considered as a valuable source of food and phytochemical compounds. The obtained data can be help to expand the inventory of wild and cultivated Trigonella species for further exploitation of rich chemotypes in the new foods and specific applications.

Unveiling the potential of A. fabrum and γ-aminobutyric acid for mitigation of nickel toxicity in fenugreek

Nickel (Ni) is a heavy metal that adversely affects the growth of different crops by inducing oxidative stress and nutrient imbalance. The role of rhizobacteria (RB) is vital to resolve this issue. They can promote root growth and facilitate the uptake of water and nutrients, resulting in better crop growth. On the other hand, γ-aminobutyric acid (GABA) can maintain the osmotic balance and scavenge the reactive oxygen species under stress conditions. However, the combined effect of GABA and RB has not been thoroughly explored to alleviate Ni toxicity, especially in fenugreek plants. Therefore, in the current pot study, four treatments, i.e., control, A. fabrum (RB), 0.40 mM GABA, and 0.40 mM GABA + RB, were applied under 0Ni and 80 mg Ni/kg soil (80Ni) stress. Results showed that RB + 0.40 mM GABA caused significant improvements in shoot length (~ 13%), shoot fresh weight (~ 47%), shoot dry weight (~ 47%), root length (~ 13%), root fresh weight (~ 60%), and root dry weight (~ 15%) over control under 80 Ni toxicity. A significant enhancement in total chlorophyll (~ 14%), photosynthetic rate (~ 17%), stomatal CO2 concentration (~ 19%), leaves and roots N (~ 10 and ~ 37%), P (~ 18 and ~ 7%) and K (~ 11 and ~ 30%) concentrations, while a decrease in Ni (~ 83 and ~ 49%) concentration also confirmed the effectiveness of RB + 0.40 mM GABA than control under 80Ni. In conclusion, fabrum + 0.40 mM GABA can potentially alleviate the Ni toxicity in fenugreek plants. The implications of these findings extend to agricultural practices, environmental remediation efforts, nutritional security, and ecological impact. Further research is recommended to elucidate the underlying mechanisms, assess long-term effects, and determine the practical feasibility of using A. fabrum + 0.40GABA to improve growth in different crops under Ni toxicity.

Current perspectives on fenugreek bioactive compounds and their potential impact on human health: A review of recent insights into functional foods and other high value applications

Despite long-standing uses in several food and medicine traditions, the full potential of the leguminous crop fenugreek (Trigonella foenum-graecum L.) remains to be realized in the modern diet. Not only its seeds, which are highly prized for their culinary and medicinal properties, but also its leaves and stems abound in phytochemicals with high nutritional and health promoting attributes. Fenugreek dual food-medicine applications and reported metabolic activities include hypoglycemic, antihyperlipidemic, antioxidative, anti-inflammatory, antiatherogenic, antihypertensive, anticarcinogenic, immunomodulatory, and antinociceptive effects, with potential organ-protective effects at the cardiovascular, digestive, hepatic, endocrine, and central nervous system levels. Effectiveness in alleviating certain inflammatory skin conditions and dysfunctions of the reproductive system was also suggested. As a food ingredient, fenugreek can enhance the sensory, nutritional, and nutraceutical qualities of a wide variety of foods. Its high nutritive density can assist with the design of dietary items that meet the demand for novelty, variety, and healthier foods. Its seeds provide essential protective nutrients and other bioactive compounds, notably galactomannans, flavonoids, coumarins, saponins, alkaloids, and essential oils, whose health benefits, alone or in conjunction with other bioactives, are only beginning to be tapped into in the food industries. This review summarizes the current state of evidence on fenugreek potential for functional food development, focusing on the nutrients and non-nutrient bioactive components of interest from a dietary perspective, and their applications for enhancing the functional and nutraceutical value of foods and beverages. New developments, safety, clinical evidence, presumed mechanisms of action, and future perspectives are discussed. HIGHLIGHTS: Fenugreek seeds and leaves have long-standing uses in the food-medicine continuum. Fenugreek phytochemicals exert broad-spectrum biological and pharmacological activities. They show high preventive and nutraceutical potential against common chronic diseases. Current evidence supports multiple mechanisms of action mediated by distinct bioactives. Opportunities for fenugreek-based functional foods and nutraceuticals are expanding.

Variability in proximate composition, phytochemical traits and antioxidant properties of Iranian agro-ecotypic populations of fenugreek (Trigonella foenum-graecum L.)

Fenugreek (Trigonella foenum-graecum L.) is a multi-use annual forage legume crop that is widely used in food products such as syrup, bitter run, curries, stew, and flavoring. In the present study, morphological traits, proximate composition (moisture, crude fibre, protein, fat, carbohydrate, and energy value), total phenol and total flavonoid contents, and antioxidant properties of 31 Iranian agro-ecotypic populations of the plant was investigated. Among the leaf and seed samples studied, the seeds exhibited the high ash (3.94 ± 0.12%), fat (7.94 ± 0.78%), crude fibre (10.3 ± 0.25%), protein (35.41 ± 1.86%), and carbohydrate (50.5 ± 1.90%) content. In general, more energy value (kcal/100 g) was also obtained from the seed (318.88 ± 1.78-350.44 ± 1.27) than leaf samples (45.50 ± 1.32-89.28 ± 0.85). Antioxidant activity and power of leaf samples were ranged from 67.95 ± 0.05‒157.52 ± 0.20 μg/ml and from 45.17 ± 0.01‒361.92 ± 0.78 μmol Fe+2 per g dry weigh, respectively. Positive linear correlations between antioxidant activity and total phenolic compounds were observed. A significant correlation between proximate composition (dependent variable) and some morphological features (independent variable) was observed. Considerable variability in the studied traits among the plant samples can be interestingly used in further food and production systems.

Identifying SNP markers associated with distinctness, uniformity, and stability testing in Egyptian fenugreek genotypes

Distinctness, uniformity, and stability (DUS) test is the legal requirement in crop breeding to grant the intellectual property right for new varieties by evaluating their morphological characteristics across environments. On the other hand, molecular markers accurately identify genetic variations and validate the purity of the cultivars. Therefore, genomic DUS can improve the efficiency of traditional DUS testing. In this study, 112 Egyptian fenugreek genotypes were grown in Egypt at two locations: Wadi El-Natrun (Wadi), El-Beheira Governorate, with salty and sandy soil, and Giza, Giza governorate, with loamy clay soil. Twelve traits were measured, of which four showed a high correlation above 0.94 over the two locations. We observed significant genotype-by-location interactions (GxL) for seed yield, as it was superior in Wadi, with few overlapping genotypes with Giza. We attribute this superiority in Wadi to the maternal habitat, as most genotypes grew in governorates with newly reclaimed salty and sandy soil. As a first step toward genomic DUS, we performed an association study, and out of 38,142 SNPs, we identified 39 SNPs demonstrating conditional neutrality and four showing pleiotropic effects. Forty additional SNPs overlapped between both locations, each showing a similar impact on the associated trait. Our findings highlight the importance of GxL in validating the effect of each SNP to make better decisions about its suitability in the marker-assisted breeding program and demonstrate its potential use in registering new plant varieties.

West meets east: open up a dialogue on phytomedicine

The desire to extend the wisdom of traditional health systems has motivated the trade of many phytomedicine on a global scale for centuries, especially some dietary herbs, making a great overlap exits between western and eastern phytomedicine. Despite the communication since ancient times, a key disconnect still exists in the dialog among western and eastern herbal researchers. There is very little systematic effort to tap into the friction and fusion of eastern and western wisdom in utilizing phytomedicine. In this review, we analyzed the similarities and differences of three representative phytomedicine, namely Rhodiola, seabuckthorn, and fenugreek, aiming to open up new horizons in developing novel health products by integrating the wisdom of the east and the west.

Combined Effects of Water Deficit, Exogenous Ethylene Application and Root Symbioses on Trigonelline and ABA Accumulation in Fenugreek

Secondary metabolites (SMs) have high economic impact thanks to their exploitability in chemical, pharmaceutical and cosmetic industries. Trigonella foenum-graecum has an importance due to the production of bioactive compounds with pharmaceutical values. Among them, the alkaloid trigonelline is known for its role in the treatment of different human diseases. SM accumulation is influenced by environmental factors but is modulated by the application of exogenous compounds. Ethephon, a precursor of the phytohormone ethylene, was already used to influence SM accumulation. Our work is aimed at evaluating the accumulation of trigonelline and the phytohormone abscisic acid (ABA) when three factors were combined: i) two levels of water regimes (well-watered and water deficit), ii) ethephon treatments and iii) inoculation with an arbuscular mycorrhizal (AM)-based inoculum also leading to nodulation. The content of trigonelline and ABA was significantly affected by symbioses, showing high accumulation in AM-colonized plants irrespective of the water regimes applied. In terms of trigonelline accumulation with respect to ethephon treatments, while symbiotic plants showed a dose-dependent trend, non-symbiotic plants showed a significantly difference only when 550 ppm of ethephon was applied. In conclusion, our work provides new information on the effects of both ethephon and symbioses on plant growth and accumulation of valuable compounds, such as trigonelline, in fenugreek.

Reactive oxygen species generating photosynthesized ferromagnetic iron oxide nanorods as promising antileishmanial agent

Aim: To investigate the photodynamic therapeutic potential of ferromagnetic iron oxide nanorods (FIONs), using Trigonella foenum-graecum as a reducing agent, against Leishmania tropica. Materials & methods: FIONs were characterized using ultraviolet visible spectroscopy, x-ray diffraction and scanning electron microscopy. Results: FIONs showed excellent activity against L. tropica promastigotes and amastigotes (IC₅₀ 0.036 ± 0.003 and 0.072 ± 0.001 μg/ml, respectively) upon 15 min pre-incubation light-emitting diode light (84 lm/W) exposure, resulting in reactive oxygen species generation and induction of cell death via apoptosis. FIONs were found to be highly biocompatible with human erythrocytes (LD₅₀ 779 ± 21 μg/ml) and significantly selective (selectivity index >1000) against murine peritoneal macrophages (CC₅₀ 102.7 ± 2.9 μg/ml). Conclusion: Due to their noteworthy in vitro antileishmanial properties, FIONs should be further investigated in an in vivo model of the disease.

Effect of alumina (Al2O3) nanoparticles and macroparticles on Trigonella foenum-graceum L. in vitro cultures: assessment of growth parameters and oxidative stress-related responses

The impact of 100 μg ml-1 alumina (Al2O3) nanoparticles (NPs) on Trigonella foenum (fenugreek) in vitro cultures was studied within 3 weeks (on days 1, 7, 14, and 21) and compared with the control and bulk (macrometer-sized particles) alumina-treated groups. Transmission electron microscopy (TEM) and dynamic light scattering were used for the characterization of NPs. The results of TEM analysis represented a nearly spherical shape for the NPs with agglomeration. The zeta potential of alumina NPs was - 25.4 ± 2.5 mV and the averaged diameter was 20 ± 5 nm. Atomic absorption and inductively coupled plasma-optical emission spectroscopy provided evidence for the release and uptake of aluminum. Treatment of cultures with NPs led to an increase in the formation of lateral roots. Treatment of fenugreek with bulk alumina caused a significant decrease in the number of leaves on day 21 (p < 0.05) and the root length on days 14 and 21 compared with the control group (p < 0.05). Alumina NP has led to a significant increase in the malondialdehyde content on days 7, 14, and 21 (p < 0.001). The glutathione content was decreased significantly in NP and bulk-treated groups on days 1 and 7 (p < 0.05). FRAP assay results showed that NPs and bulk alumina led to a decrease in the antioxidant power on days 7, 14, and 21 (p < 0.001). The increased activity of catalase (p < 0.001) and ascorbate peroxidase (p < 0.001) was observed in the bulk-treated group. Lignin content had a significant increase in response to NPs on days 14 and 21 (p < 0.001). Conclusively, alumina nano/macro particles affected agronomical and physiological properties of T. foenum; however, smaller sized particles do not necessarily imply greater toxicity, while uptake of the aluminum ions should be considered seriously.

CO2 treatment improves the hypocholesterolemic and antioxidant properties of fenugreek seeds

A high level of serum cholesterol is a major cause of atherosclerosis. Fenugreek is a well-known hypocholesterolaemic agent with amazing phytochemical composition. Due to its impact on plant metabolism, CO₂ enrichment was tested as a strategy to support functional values in fenugreek seeds. Phytochemical composition and biological activities of three fenugreek cultivars (G2, G6 and G30) grown under ambient (aCO₂, 400 μmol mol^-1) and elevated CO₂ (eCO₂, 620 μmol mol^-1) were assessed. Applying eCO₂ improved physical parameters of fenugreek seeds, and enhanced their biological activities. A significant increase in hypocholesterolaemic potential, as indicated by inhibition of cholesterol micellar solubility and pancreatic lipase activity, was recorded. In addition, antioxidant, anti-lipid peroxidation and antibacterial activities were improved. These enhanced biological activities were accompanied by improved seed chemical composition at the primary and secondary metabolic levels. Therefore, eCO₂ treatment represents an efficient strategy to increase the hypocholesterolaemic, antioxidant and antibacterial activities of fenugreek seeds.

Fenugreek Seed Powder Nullified Aluminium Chloride Induced Memory Loss, Biochemical Changes, Aβ Burden and Apoptosis via Regulating Akt/GSK3β Signaling Pathway

Alzheimer's disease (AD) is the most common form of dementia that mainly affects the cognitive functions of the aged populations. Trigonella foenum-graecum (L.) (fenugreek), a traditionally well utilized medicinal plant ubiquitously used as one of the main food additive worldwide, is known to have numerous beneficial health effects. Fenugreek seed extract could be able to inhibit the activity of acetylcholinesterase (AChE), a key enzyme involved in the pathogenesis of AD, and further shown to have anti-parkinsonic effect. The present study was aimed to explore the neuroprotective effect of fenugreek seed powder (FSP) against aluminium chloride (AlCl₃) induced experimental AD model. Administration of germinated FSP (2.5, 5 and 10% mixed with ground standard rat feed) protected AlCl₃ induced memory and learning impairments, Al overload, AChE hyperactivity, amyloid β (Aβ) burden and apoptosis via activating Akt/GSK3β pathway. Our present data could confirm the neuroprotective effect of fenugreek seeds. Further these results could lead a possible therapeutics for the management of neurodegenerative diseases including AD in future.

Fenugreek a multipurpose crop: Potentialities and improvements

Fenugreek is one of the oldest medicinal plants with exceptional medicinal and nutritional profile. Fenugreek seeds contain a substantial amount of fiber, phospholipids, glycolipids, oleic acid, linolenic acid, linoleic acid, choline, vitamins A, B1, B2, C, nicotinic acid, niacin, and many other functional elements. It may grow well under diverse and a wide range of conditions; it is moderately tolerant to drought and salinity, and can even be grown on marginal lands in profitable way. Owing to these characteristics and heavy metal remediation potential, fenugreek may well fit several cropping systems. In addition to its medicinal uses, it may serve as an excellent off-season fodder and animal food supplement. However, efforts should be initiated to develop strategies for improving its biomass production; genetic diversity among different accessions may be mapped, breeding and crop improvement programs may be initiated to improve the biomass and nutritional and functional elements. This review highlights the morphology, adaptability, nutritional constituents and associated functionality and medicinal significance of fenugreek; its ethno-historical uses, pharmacological assumptions have also been discussed. Researchable areas are also indicated to improve its production and adaptability.

Investigating Therapeutic Potential of Trigonella foenum-graecum L. as Our Defense Mechanism against Several Human Diseases

Current lifestyle, stress, and pollution have dramatically enhanced the progression of several diseases in human. Globally, scientists are looking for therapeutic agents that can either cure or delay the onset of diseases. Medicinal plants from time immemorial have been used frequently in therapeutics. Of many such plants, fenugreek is one of the oldest herbs which have been identified as an important medicinal plant by the researchers around the world. It is potentially beneficial in a number of diseases such as diabetes, hypercholesterolemia, and inflammation and probably in several kinds of cancers. It has industrial applications such as synthesis of steroidal hormones. Its medicinal properties and their role in clinical domain can be attributed to its chemical constituents. The 3 major chemical constituents which have been identified as responsible for principle health effects are galactomannan, 4-OH isoleucine, and steroidal saponin. Numerous experiments have been carried out in vivo and in vitro for beneficial effects of both the crude chemical and of its active constituent. Due to its role in health care, the functional food industry has referred to it as a potential nutraceutical. This paper is about various medicinal benefits of fenugreek and its potential application as therapeutic agent against several diseases.

Efficient Protocol for Isolation of Rhaponticin and Rhapontigenin with Consecutive Sample Injection from Fenugreek (Trigonella foenum-graecum L.) by HSCCC

High efficiency and less solvent consumption are the essential requirements of high-speed countercurrent chromatography (HSCCC), especially for the large-scale preparation. In this study, an efficient HSCCC strategy with consecutive sample injection was successfully developed to rapidly separate and purify rhaponticin and rhapontigenin from the seeds of the Chinese medicinal herb fenugreek (Trigonella foenum-graecum L.). The effective separation was achieved using n-hexane-ethyl acetate-methanol-water (1:4:2:6, v/v/v/v) as the two-phase solvent system, in which the mobile phase was eluted at an optimized flow rate of 2.2 mL/min and a revolution speed of 850 rpm. After consecutively loading four identical fenugreek samples, each containing 120 mg, HSCCC separation yielded 146.4 mg of rhaponticin and 174.8 mg of rhapontigenin with purities of 98.6 and 99.1%, respectively, as determined by high-performance liquid chromatography at 320 nm. Their chemical structures were identified using UV spectroscopy, (1)H-NMR and (13)C-NMR. The HSCCC method with consecutive sample injection allowed faster separation and produced less solvent waste, suggesting that it is an efficient way to rapidly separate and purify natural products on a large scale.

Fenugreek (Trigonella foenum-graecum L.) as an alternative forage for dairy cows

Fenugreek is a novel forage crop in Canada that is generating interest as an alternative to alfalfa for dairy cows. To evaluate the value of fenugreek haylage relative to alfalfa haylage, six, second lactation Holstein cows (56 ± 8 days in milk), which were fitted with rumen cannulas (10 cm i.d., Bar Diamond Inc., Parma, ID, USA) were used in a replicated three × three Latin square design with 18-day periods. Diets consisting of 400 g/kg haylage, 100 g/kg barley silage and 500 g/kg concentrate on a dry matter (DM) basis were fed once daily for ad libitum intake. The haylage component constituted the dietary treatments: (i) Agriculture and Agri-Food Canada F70 fenugreek (F70), (ii) Crop Development Center Quatro fenugreek (QUAT) and (iii) alfalfa (ALF). DM intake (DMI), milk yield and milk protein and lactose yields were higher (P < 0.001) for cows fed ALF than fenugreek (FEN, average of F70 and QUAT). Milk fat of cows fed FEN contained lower concentrations of saturated, medium-chain and hypercholestrolemic fatty acids (FAs; P < 0.05) than that of cows fed ALF. Apparent total tract digestibility of DM and nutrients was not affected by treatments. Similarly, individual ruminal volatile FA concentrations and rumen pH (5.9) were not affected by treatments. Rumen ammonia-N concentration was higher for FEN than ALF (P < 0.001). Estimates of neutral detergent fiber (NDF) passage rate (P < 0.05) and NDF turnover rate (P < 0.001) in the rumen were higher for ALF than FEN. Our results suggest that although the digestibility of the FEN diets was not different from that of the ALF diet, fenugreek haylage has a lower feeding value than ALF for lactating dairy cows due in part to lower DMI and subsequently lower milk yield.

Biochemical monitoring in fenugreek to develop functional food and medicinal plant variants

Many plants used as functional foods or for medicinal purposes have been criticized for their inconsistent physiological effects. Variation in genotype and environmental conditions under which plants are produced can contribute to this inconsistency in biochemical composition. Fenugreek (Trigonella foenum-graecum L.) is a medicinal plant that not only can lower blood glucose and cholesterol levels in animals, but also can be used as a forage crop for livestock feed. Seed content for the bioactive compounds diosgenin, galactomannan and 4-hydroxyisoleucine was characterized for ten fenugreek genotypes under rainfed and irrigated conditions. High and low seed yielding genotype/environment combinations were identified that possessed distinct biochemical and seed production traits. In general high seed yielding genotype/environment combinations exhibited a more stable biochemical composition and consisted largely of irrigated fenugreek. This research indicates that comprehensive biochemical analysis of plant products would facilitate the development of more reliable produce for use by the functional food/medicinal plant industry.