Phytochemical screening and in-vitro biological properties of unprocessed and household processed fenugreek (Trigonella foenum-graecum Linn.) seeds and leaves

The impact of household processes on fenugreek leaves and seeds has been analyzed for total phenolic (TP) and total flavonoid content (TF), and in-vitro biological activities such as antioxidant, antimicrobial, and anti-inflammatory properties. Processes included air-drying for leaves and germinating, soaking, and boiling for seeds. Air-dried fenugreek leaves (ADFL) had high TP (15.27 mg GAE g(−1) D.W.) and TF (7.71 mg QE g(−1) D.W.) (milligram quercetin equivalents per gram dry weight). The TP contents of unprocessed, germinated, soaked, and boiled seeds were 6.54, 5.60, 4.59, and 3.84 mg gallic acid equivalents per gram of dry weight (mg GAE g(−1) D.W.), respectively. The TF contents in unprocessed fenugreek seeds, germinated fenugreek seeds, soaked fenugreek seeds, and boiled fenugreek seeds (BFS) were 4.23, 2.11, 2.10, and 2.33 mg QE g(−1) D.W., respectively. Sixteen phenolic and nineteen flavonoid compounds has been identified using high-performance liquid chromatography. Antioxidant activity using 2,2-diphenyl-1-picrylhydrazil (DPPH(·)), 2,2-azinobis (3-ethylbenothiazoline-6-sulfonic acid (ABTS(+·)), and ferric reducing antioxidant power (FRAP(·)) assays indicated that ADFL had the highest activity. Antimicrobial activity has been evaluated against each of the eight pathogenic bacterial and fungal strains. ADFL showed the strongest activity with minimum inhibitory concentrations values ranging from 0.03 to 1.06 and 0.04 to 1.18 mg ml(·1) against bacterial and fungal strains, respectively. Anti-inflammatory activity was evaluated in-vitro against RAW 264.7 macrophage cells using the nitric oxide (NO) assay. Results revealed that ADFL had the highest cytotoxicity and anti-inflammatory activity according to the NO assay. Household processes significantly reduced the in-vitro biological properties of processed seeds.