Trigonella foenum-graecum, (L., Family-Fabaceae) Fenugreek (Eng), Methi (Hindi), Fenugrec (Fre), Bockshorklee (Ger),Koroha (Jap),Hulba (Arab),Pazhitnik (Rus), K'u-Tou (Chin), Alholva (Spa), Fieno greco (Ital), Halba (Malay), has been in use for over 2500 years. India continues to be the major source and main consumer for culinary and medicinal uses. With extract used to flavor cheese in Switzerland, artificial maple syrup and bitter rum in Germany, roasted seeds as coffee-substitute in Africa, seed powder mixed with flour as fortification to make flat-bread in Egypt, as an anti-diabetic herb in Israel, whole seed and dried plant used as insect and pest repellent in grain storage, oil used in perfumery in France, fenugreek is becoming popular around the world. Aqueous seed extract is antibacterial, and was used as poultice in traditional veterinary medicine. In Ayurvedic system, it is "Katu ushna, causes hemorrhagic diseases, effective against anorexia, subdues deranged vata, and is a gastric stimulant" (Rajni-ghantu).

Fenugreek plant and cultivation: The seed sown on a prepared soil sprouts in 3 days, grows inherently resistant to most infestations and diseases needing little care to a robust, erect, scented plant to 30 to 60 cm tall, with compound pinnate trifoliate leaves, axillary white to yellowish flowers, 3 - 15 cm long thin pointed beaked pods, with 10 to 20 oblong greenish-brown seeds with unique hooklike groove. As a leguminous plant it fixes atmospheric nitrogen, thus enriching the soil. Greens are harvested at the 3 or 4-leaved stage, after when saponin content increases, making it more bitter. The seeds are harvested 30 to 35 days after flowering or 155 to 165 days after sowing.

Fenugreek greens: Fresh or dried fenugreek leaves and tender stems are edible. For 100 g of leaves, there is- 86% moisture, 4.4% protein, 1% fat, 1% fiber, 395 mg Ca, 67 mg Mg, 51 mg P, 16.5 mg Fe, 76 mg Na, 31 mg K, 260 mcg Cu, 167 mg S, 165 mg Cl, 2.3 mg carotene (mainly beta, 329 IU Vit A), 40 mg thiamine, 310 mg riboflavin, 800 mcg nicotinic acid, and 52 mg Vit C; with traces of Vit K, and high amounts of choline (13.5 mg/g). Coefficient of true digestibility of leaf-protein is 77%, and its biological value 84%.

 Fenugreek seeds: Seeds are aromatic, bitter, carminative, galactogouge, antibacterial and may be eaten raw or cooked. Bulk of the seed is dietary fiber (50%) and protein (30%) both of which have no taste or flavor. Bitterness is mainly due to the oil, steroidal saponins and alkaloids. For 100 g of mature seeds, there is 30 g protein, 30 g (gel-forming) soluble fiber (15% galactomannan in the endosperm), 20 g insoluble fiber, 7.5 g lipids (6.3 g neutral- mainly triglycerides, 450 mg phospholipids- mainly phosphotidyl choline & phosphotidyl ethanolamine, 135 mg soluble lecithin), 2 g sapogenins (diosgenin, gitogenin, furastanol, yamogenin etc.), 160 mg Ca, 1.5 mg ionizable Fe (total Fe 14 mg), 370 mg phosphorous (phytin 157 mg), 19 mg Na, 530 mg K, 33 mg Cu, 100 mcg Cr, 1550 mg Mn, 160 mg Mg, 7 mg Zn, 16 mg S, 165 mg Cl, 50 mg choline, 380 mg trigonelline, traces of gentianine & carpaine, 43 mg ascorbic acid, 96 mcg carotene, 340 mcg thiamine, 290 mcg riboflavin, 1100 mcg nicotinic acid, 84 mcg folic acid of which 14.5 mcg is free folic acid and 120 U of heat-labile trypsin inhibitor.

Extraction of Seeds: A combination of organic solvents and physical conditions may be used to separate oleoresin from seed powder. A novel method (US Patent issued to Vitamed, 1997) uses non-toxic, completely removable solvent to separate the stabilized-defatted-fiber-protein (SDF) powder and the oleoresin in commercial scale (see table). Removing the oil and the saponin-alkaloids bestows long shelf-life to SDF. SDF powder has been shown to help lower levels of cholesterol, triglycerides, blood-sugar and insulin levels in individuals.

Fenugreek protein: Per the 1965 WHO/FAO protein assessment, the nutritive value of SDF is 65 in comparison to egg protein. Surprisingly, methionine is the only essential amino acid missing in mature seed, but found in germinating seeds.

Isoflavones in Fenugreek: Luteolin, quercetin, kaempferol etc. are found in fenugreek. The biological activity of these compounds are under intense study.

 Fenugreek saponins and alkaloids: Fenugreek contains approximately 4 to 8 % saponins and about 1% alkaloids, contributing to bitterness, gastric stimulation, increased acidity, increased appetite, and weight-gain. Traditionally, Persians and Arabs used fenugreek seeds to increase lean muscle mass in women. Diosgenin, the main sapogenin, is an estrogen precursor, and may help in managing menopause. In regions where fenugreek is used in food, the symptoms of menopause are considered mild. Saponin-rich extract induces release of testosterone in males, increases secretory functions induces uterine contractions in females. For this reason fenugreek extract and leaf (usually rich in saponins) must be contraindicated in women during early pregnancy to avoid risk of fetal loss, and during menstruation to reduce risk of excessive bleeding. Biological enlargement of breast tissue has been claimed with the use of whole seeds and leaf. Saponins can reduce cholesterol, albeit small, via hormone synthesis without effect on triglycerides and bind to dietary lipids. Trigonellin, an alkaloid, is thought to reduce glycosuria in diabetes.

Fenugreek oils- The extractable oil (6-8%) has a foetid odor, bitter taste with marked drying properties, sp gr 0.91, acid value 1-2, saponification value 178 - 183, iodine value 115, unsaponifiable matter 3.9%, and fatty acids (palmitic 9.6%, stearic 4.9%, arachidic 2%, oleic 35.1%, linoleic 33.7%, and linolenic 13.8%). About 20 mg% is volatile oil (sp gr 0.87 at 15.5 C, optical rotation + 10.8) with anethol as major component. The odor may resemble that of roasted coffee or maple syrup. The unsaponifiable portion contains the lactation stimulating factor. Traditionally, whole seed was used in postpartum period to increase lactation in women and cattle. The oil is also used for cosmetic purposes, traces used in perfumes, and is reported to have insect and pest repellent properties, though no effect on dog ticks, mosquitoes or flies was noticed.

Fenugreek fibers: Dietary fibers are indigestible complex carbohydrate obtained from plants, but essential ingredient in a healthy diet. Some are soluble to form gel and others form insoluble roughage. While most fruits and vegetables have insoluble fibers, legumes (guar, fenugreek, beans) have soluble fiber. Fenugreek is endospermic. Nearly 50% dry weight of seeds as well as SDF is edible dietary fiber, making it the highest concentration among all natural sources of fiber. About 30% of SDF (w/w) is gel-forming SOLUBLE fibers similar to guar gum, psyllium husk and oat bran. The INSOLUBLE fiber (20% of SDF), is bulk-forming like wheat bran.
 

SDF is very Versatile: SDF is very stable, with a long shelf life. It withstands frying, baking, cooking, and freezing. Minor modification in the physical conditions of processing can yield SDF with distinct water absorption properties. Thus, SDF with a high water retention capacity is made into jelly, spreads, and used as thickener. SDF can be taken as plain powder mixed in fruit juices or may be added to food items such as soups, beverages, sauce, etc. Adding SDF to refined flour helps to fortify with a balance of soluble and insoluble fibers. Flour fortified with 8 to 10% SDF has been used to prepare bakery foods like pizza, bread, muffins, and cakes. Since SDF has a very faint aroma of maple syrup, these products will gain flavor. SDF has also been incorporated into flour to make chips, flat-bread (chapathi), wafers (papads), and taco shells. By fortifying such food items with fiber, one can increase the total fiber intake in a day. RDA for fibers is 20 to 30 g a day which can be easily taken as SDF. The variety increases the options of fiber supplementation.

SDF and Regularity: Colonic transit time of diet with SDF is short. SDF improves regularity, reduces colonic bioburden, with little or no flatulence, increases fecal mass, reduces risk of constipation and makes defecation very smooth and easy. This reduces risk of diverticulosis, hemorrhoids, and anal fissures.

SDF and Obesity: Fiber in diet helps by replacing calories, increasing chewing time, suppressing appetite, controlling overeating and arresting weight-gain. SDF induces satiety (feeling of fullness), delays gastric emptying and increases mouth-to-cecum transit time. With 30 g SDF a day and appropriate physical activity, gradual and significant weight-loss can be easily achieved without adverse protein-calorie malnutrition and other ill-effects of dieting. SDF suppresses weight-gain whereas the saponins enhance weight-gain. Persons considering weight-loss should make sure the SDF has no residual saponins.

SDF and Diabetes: Yemanite Jews used fenugreek seeds in the management of diabetes. Although the mechanism of fenugreek action in humans is not understood, animal studies have revealed the ability of SDF to delay gastric emptying, suppress the release of gastric inhibitory peptides and insulinotropic hormones. The diminished post-prandial glucose peak observed with SDF supplementation is extended over a longer period. Also, a normo-glycemia over longer period would ensure higher energy level without demand for frequent feeding. By giving SDF to alloxan-treated rabbits and rats (alloxan treatment specifically destroys insulin secreting cells in pancreas and makes these animals diabetic), a significant reduction in fasting blood sugar level was noticed. In a study of insulin dependent diabetic (IDDM) patients, oral glucose tolerance test (GTT) improved in 10 days after starting on SDF. The time of administration of SDF does not alter improvement on GTT. Sensitivity to insulin improves with high-fiber diet. IDDM patients who started on 100 g SDF a day experienced a need to lower the insulin dosage after just 10 days, which was apparent clinically soon afterwards. SDF, like guar gum reduces urinary loss of sugar by over 50%. A significant reduction of fasting sugar level and improved GTT was observed in non-insulin dependent (NIDDM) diabetic patients, indicating that SDF acts not only on sugar digestion and absorption in the gastrointestinal lumen, it also reduces insulin levels and influences the utilization of glucose at the cellular level.

SDF for Cholesterol and Triglyceride : High levels of LDL and VLDL cholesterol is associated with atherosclerosis or plaque in the blood vessels. A reduction in the levels is considered important to reduce risk of heart attack. Unlike poly-unsaturated fatty acids (PUFA) which reduce HDL as well as other cholesterols, SDF selectively reduces only LDL+VLDL and triglycerides. Physiologically, but not nutritionally, soluble fibers behave like fat. SDF ingestion results in premature emptying of gall-bladder. The released bile is trapped in the fiber gel, preventing re-absorption in the distal ileum. This forces the liver to make new bile from circulating cholesterol, resulting in a significant reduction by depleting cholesterol storage. Traditionally 4F's (Fat, Fertile, Forties, Female) were considered risk factors for developing gall-stones. People who live on fat-free diet tend not to use the stored bile, and may increase their risk of developing gall-stones. Since SDF helps to empty gall-bladder with every dose, this appears to be the best preventive measure. The reduction in triglycerides seen with SDF, and not with other fibers, may be more than due to lowering the VLDL synthesis, interference with absorption from dietary sources, or control of glycemia. High triglycerides are associated with recurrent attacks of acute pancreatitis. SDF increases excretion of undigested dietary fat with bile acids and neutral sterols in stool. Oat bran and guar gum (both are soluble fibers) have demonstrated selective reduction of LDL level. The effect of SDF on serum lipids was sustained and lasting for several weeks after stopping, without any adverse side effects or intolerance.

SDF for Enteral Feeding: Incorporation of fiber in enteral feeding has been associated with expedited healing in patients undergoing gastrointestinal surgery. However, enteral feed products with fiber posed a difficulty due to the fast gelling of the fiber ingredient which blocked the feeding tube. Since the gelling time for SDF is over 10 minutes, it is easier to administer through the tube without obstruction.

Safety of Fenugreek Fibers: No toxicity was found when 100 g of SDF was fed to volunteers, or at 2 g /kg body-wt in mice, or at 5 g /kg body-wt in rats. Fenugreek being a member of legume family, like soy and peanuts, can cause allergy. This risk is only for users of whole seeds and powders which contains fenugreek protein. Adequate fluid intake is a necessity for all fibers. RDA for dietary fibers is 20 g for 2000 kcal per day.

Warning: Taking any fiber product without adequate liquids may cause it to be stuck in the esophagus, swell and choke the individual. Do not consume alcoholic beverages with fibers. Avoid fenugreek saponin extract before or during menstrual periods or when considering pregnancy.

References: Wealth of India, 1985, Phytother Res 10:332-34, 1996; ibid 5:145-47, 1991; Brit J Nutri 69:277-87, 1993; Food Chem 24:1-9, 1987; J Food Sci Technol 10:179-81, 1973: Eur J Clin Nutri 44:301-06, 1990; Nutri Res 10: 731-39, 1990; Treatise on Indian Med Plants, 1992; Useful Plants of India, 1992, Indian Medicinal Plants Vol 5, 1996.