The bioactive components of fenugreek, like galactomannan, saponins, trigonella, diosgenin, and 4-hydroxyisoleucine, have been reported to exert positive effects on diabetes. Several components have been isolated, and various studies have revealed their action on blood sugar [14]. Fenugreek controls diabetes via multi-physiological pathways, such as restoring pancreatic β-cell function and inhibiting sucrase as well as alpha-amylase activities. 4-Hydroxyisoleucine directly induces insulin secretion from pancreatic β-cells. Fenugreek saponin extract has shown anti-diabetic, hepatoprotective, and hypolipidemic effects [2, 15-17]. Fenugreek saponins regulate glycogen enzyme activities in the intestine and liver of rats, enhance hepatic glycogen content, lower blood glucose levels, and improve oral glucose tolerance [18]. In a study, 15 diabetic patients were given fenugreek seed powder for 10 days, which resulted in a significant reduction of fasting glucose level, LDL, and VLDL cholesterol and improved glucose tolerance. This also led to a 64% reduction in 24 hr urinary glucose excretion [19]. Galactomannan, one of the components of fenugreek, exhibits protection against diabetes. A group of 32 patients (type-2 diabetic) were given galactomannan and compared with the control (32 patients placebo). The study revealed a notable decrease in fasting blood glucose, HbA1c, total cholesterol, triglycerides, and low-density lipoprotein. Overall, galactomannan could be a good candidate for hyperglycemia and hypolipidemia. Diosgenin, a glycan in fenugreek, boosted glucose metabolism by stimulating adipocytes, inhibiting inflammation in adipose tissue, and lowering triglycerides in the plasma of obese diabetic mice. In research, it was observed that 10 gm/40 ml of liquid fenugreek extract could reduce the glucose level of blood. It was found that its liquid dosage is better than crushed and powdery forms [2].

Impairments of the liver can be favorably cured or controlled by the supplementation of antioxidants. Components like diosgenin, saponins, flavonoids, and polyphenol possess antioxidant, hypolipidemic, and hypocholesterolemic properties. In one study, fenugreek improved lipid profile and collagen content in the hepatotoxic Wistar rats at a dose of 200 mg/kg per day [20]. In another study, fenugreek reduced lipid aggregation in the liver by increasing lipid excretion in feces. Serum total cholesterol, low-density lipoproteins, very low-density lipoproteins, cholesterol, and triglycerides were also significantly reduced. However, the high-density lipoprotein and cholesterol fraction remained unchanged [21]. Active components of fenugreek, such as 4-hydroxyisoleucine and galactomannan, lowered blood glucose levels and improved lipid metabolism. Metabolic and hepatic damage that occurred after ischemia-reperfusion could be prevented by fenugreek. Fenugreek was found to be effective in reducing damage caused by ischemia-reperfusion. It has been shown that polyphenols and flavonoids are helpful in treating hepatic ischemia. The exposure of fenugreek extract to rats showed that the levels of plasma serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) levels were significantly reduced, thus showing the hepatoprotective effects [22].

Studies have revealed that fenugreek seeds are effective in lowering cholesterol levels and thus may also act as a cardioprotective agent [23]. The constituents of fenugreek, such as saponins, diosgenin, galactomannan, coumarin, fenugreekine, nicotinic acid, sapogenins, phytic acid, scopoletin, and trigonelline, have pharmacological properties. The effect of fenugreek was studied on isoproterenol-induced myocardial infarction in rats. The study revealed the cardioprotective effect of fenugreek in rats by increasing the activities of both enzymatic and non-enzymatic antioxidants (SOD, CAT, GPx, and GSH) [24]. Fenugreek strongly regulates blood lipid levels; hence, it is effective against atherosclerosis by lowering cholesterol, triglycerides, and LDL levels and raising HDL levels [12]. Fenugreek, a good anti-oxidant, protects the myocardial tissue from oxidative stress and improves metabolic abnormalities. One of the studies demonstrated the protective effect of the hydro-alcoholic extract of fenugreek seeds in STZ-induced diabetic rats. The results showed that fenugreek seed extract has the potential to treat diabetic cardiomyopathy by altering the expression of genes involved in apoptosis. It was reported that the expression of pro-apoptotic Bax gene and intercellular adhesion molecule was downregulated, and the anti-apoptotic gene BCl2 was upregulated, indicating the anti-oxidant and anti-apoptotic property of fenugreek [25].

Lifestyle and unhealthy diet style result in abdominal discomfort, loss of appetite, nausea, vomiting, gastric ulcer, and peptic ulcer. There are several studies reporting the beneficial role of fenugreek against gastrointestinal diseases. It possesses anti-ulcer, anti-inflammatory, gastroprotective, antioxidant as well as anti-secretory properties. The study on Albino rats revealed that when fenugreek seeds were orally given to rats, the severity of ulcers reduced significantly compared to the untreated group of rats [26]. Mucosal damage, hyperaemia, submucosal oedema, and severe congestion of vessels marked by HCl-ethanol induced in rats were significantly lowered in pre-treated rats with fenugreek seeds [27]. The fenugreek seed gel fractions of 700 mg/rat given orally proved anti-ulcerogenic. Gel fraction showed significantly less lesion formation, altered gastric secretion, reduced lipid peroxidation, and increased antioxidant capacity of the gastric mucosa [28]. Sugaheal®, the 4-hydroxyisoleucine and trigonelline enriched fraction (TF4H 28%), a well-known anti-diabetic drug possesses good antioxidant properties. In a study, sugaheal given to Wistar rats showed the beneficial property against gastric ulcers. Microscopic analysis of the stomach wall revealed a reduction in ulcer spots. A 100 mg/kg body weight (BW) dose of sugaheal displayed maximum protection against ROS damage mediated by a 48 mg/kg BW dose of indomethacin in a rat's stomach [8]. The polyphenols present in fenugreek are responsible for treating gastric and acute gastric injuries induced by chemicals [29]. Fenugreek seeds improve appetite and gastric discomfort, and their oral administration enhances salivary flow as well as lactase activity [26].

Fenugreek contains a bioactive compound, ‘diosgenin,’ which is an anti-cancer agent [30]. Several studies have shown the benefit of fenugreek against cancerous cells by inducing apoptosis. Diosgenin arrests the G1 phase of the cell cycle (in both MCF-7 and MDA-231 cells) by downregulation of cyclin D1 and cdk-2. Treatment with diosgenin showed upregulation of p21 without involving p53 in the treated cells. It was also found to be involved in the up- and down-regulation of the protein involved in the apoptosis of cells (in vivo as well as in vitro) [31]. Levels of Bcl2 decreased in the breast cancer (BCa) cells, and the activity of caspase 3 increased in the treated cells compared to control cells. The results showed that diosgenin influences the apoptotic pathway in cancerous cells. Akt-mediated signaling, crucial for the progression of breast cancer cells, was downregulated by the treatment of diosgenin [31]. Thymoquinone and diosgenin possess anti-neoplastic property as they increase the expression of apoptotic genes and caspase activity, inhibit Akt and JNK phosphorylations, and thus prevents cell division. These two bioactive components possess synergistic effects and anti-proliferative properties [30]. A study showed that intraperitoneal administration of the fenugreek seed extract caused 70% inhibition of tumor cell growth compared to control and modulated 1,2-dimethylhydrazine-induced hepatic oxidative stress during colon carcinogenesis by increasing catalase, superoxide dismutase, glutathione-s-transferase activities in the liver of treated animal [4]. Fenugreek possesses a cytotoxic property, which has shown to be useful in the prevention and treatment of cancer [32]. According to a study, treatment with 10-15 ug/ml of FE for 72 hr showed inhibition of tumor growth in breast, pancreatic, and prostate cancer cell lines (PCa) [33].

Reproductive health benefits of fenugreek include regulation of sex hormones, sperm viability, sperm count, and other sexual dysfunction in both genders. Bioactive components of fenugreek, such as steroidal saponins (Diosgenin and yamogenin), possess anti-sterility and anti-androgenic effects. According to some studies, saponin binds to estradiol receptors and modulates the activity of E2 in the rat model of Ovarian Hyperstimulation Syndrome [34]. Diosgenin regulates sexual activity by stimulating growth hormones from the pituitary [35]. Diosgenin is a precursor used for the majority of commercially available cortisone, pregnenolone, progesterone, and other steroids. Rats exposed to fenugreek powder, oil extract, and aqueous extract altered sex hormone levels, sperm count, and sperm viability [35].

The antimicrobial property of fenugreek has become popular among various herbal extracts. The effectiveness of fenugreek against many bacteria has been studied. Sulieman et al. [36] studied the antimicrobial property of fenugreek against Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, and Aspergillus niger. They reported that the 100% concentrated fenugreek oil showed maximum inhibition against Escherichia coli rather than Salmonella typhimurium and Staphylococcus aureus. Ethanolic extract of fenugreek seed was also tested on 6 bacterial strains, including Staphylococcus aureus, Pseudomonas aeruginosa, Proteus mirabilis, Salmonella typhi, Escherichia coli, and Vibrio parahaemolyticus, with low to moderate activity except on Staphylococcus aureus and E. coli [37]. Phytochemical analysis showed the antibacterial properties of fenugreek seed extracts due to the presence of alkaloids, flavonoids, tannins, saponins, terpenoids, and steroids [38]. The antibacterial activity of AgNPs synthesized using fenugreek leaves extract was tested against S. aureus, E. coli, P. aeruginosa and V. cholera, with an inhibition zone of 6, 12, 11, and 6 mm, respectively. Fenugreek leaves contain bioactive components, such as flavonoids, including quercetin, vitexin, and kaempferol and glycosides, phenolic compounds, and ascorbic acid, which act as a bioactive source or reducing agent for the synthesis of silver nanoparticles [39]. Phytoconstituents, particularly polyphenols, showed low to strong effects on most tested strains, with a strong antibacterial effect of fenugreek compared to aqueous extracts [40]. An in vitro study on methanolic and petroleum ether extracts of seeds and callus extracted from hypocotyls and cotyledons explants of fenugreek against standard microorganisms, Bacillus, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Aspergillus niger, and Candida albicans reported antimicrobial activity of petroleum ether extract with inhibition zones of 17±0.33mm and 15±0.57mm against Escherichia coli and Staphylococcus aureus, respectively, which were higher than methanolic extract [41]. The minimum inhibitory concentration (MIC) recorded was 6.25 to 25 mg/ml of Trigonella foenum-graecum leaf extract, showing significant antibacterial properties that could be therapeutic for a wide range of drug-resistance microorganisms with minimal or no side effects [42].

Multi-drug resistant strains of pathogenic fungi have led to the utilization of medicinal plants and compounds isolated from them for their antifungal property. Extract of fenugreek was proved to be effective against pathogenic fungi strains of Candida species [43]. A study on ethanolic extract of fenugreek showed the highest zone of inhibition of 16.510+ 0.85 mm and 38.395% of mycelial inhibition using 100 µl of concentration against Microsporum gypseum. Such antifungal property of fenugreek is due to the presence of secondary metabolites, such as flavonoids, saponins, alkaloids, steroids, and tannins [44]. Maximum zone of inhibition, i.e., 20±0.88 mm against Aspergillus niger by concentration 250 mg/ml and 17±0.57mm of inhibition zone against Candida albicans by concentration 250 mg/ml have been recorded by petroleum ether extract of fenugreek seeds [41]. A novel defensin-like antifungal peptide (Tf AFP) of molecular mass 10.3 kDa has been isolated from Trigonella foenum graecum (fenugreek) and demonstrated antifungal properties against Fusarium oxysporum, Fusarium solani, and Rhizoctonia solan fungal species [45]. Elsidding et al. [46] synthesized silver nanoparticles using fenugreek extract as an antifungal agent against Candida albicans. Three different concentrations of silver nitrate were mixed with fenugreek extract, which served as a reducing agent and generated silver nanoparticles.

Several studies reported the immunomodulatory activity of fenugreek on immune functions, including humoral immunity, leucocytic count, phagocytic index, serum globulins, and related genes. Mice treated with three different doses of aqueous extract of fenugreek showed increased activity of humoral immunity at 100 mg and delayed hypersensitivity. The phagocytic index and phagocytic capacity of macrophages were significantly elevated in the treated mouse model [47]. The dietary supplement action of fenugreek (Trigonella foenum graecum) with gilt-head seabream (Sparus aurata L.) was found to stimulate the immune system by up-regulating immune-related genes along with significant improvement in the hematological parameters [48] and enhance skin mucosal immunity response by increasing some enzymatic activities [49]. Fenugreek combined with prebiotic strains showed a significant rise in the expression of immune-related genes (igm, tcr-β, csfr1, and bd) and the growth performance of the species [50]. In addition, fenugreek extract refined the immune system of egg-laying hens and production performance [51]. Ebrahimi et al. [52] reported remarkable improvement in the levels of immunoglobulins (IgG), lymphocytes, and leukocytes in obese women after 6 weeks of regular, intense training and fenugreek supplementation. Hematological parameters analysis revealed that the extract notably (p<0.05) enhanced Hb, RBC, and WBC count at a dose of 400 mg/kg body weight in the rodent model [53]. Therefore, the efficacy of fenugreek on hematological parameters could be used to strengthen the immune system.