INHIBITION OF α-AMYLASE AND α-GLUCOSIDASE BY (6RS)-22-HYDROXY-23,24,25,26,27-PENTANOR-VITAMIN-D3-6,19-SULFUR DIOXIDE-ADDUCT, MANOALIDE AND 5β-CHOLESTANE-3α,7α,12α,24,25,26-HEXOL ISOLATED FROM ACETONE EXTRACT OF HELIANTHUS ANNUUS L. SEEDS

Abstract

Objective: This investigation includes characterization of phytochemicals from acetone extract of Helianthus annuus L. seeds responsible for α-amylase and α-glucosidase inhibition revealed from in vitroand in silico approaches. Methods: Seed extract was qualitatively and quantitatively analysed for the presence of bioactive molecules. In vitro α-amylase and α-glucosidase inhibition assays and kinetics studies for α-glucosidase were done. Thin layer chromatography (TLC) autography of extract was done to screen potent inhibitors and characterized by high-resolution liquid chromatography-mass spectrometry (HR LC-MS). Characterized molecules were further used for in silico studies. Results: Qualitative investigation reveals the presence of flavonoids, glycosides, alkaloids, terpenoids, and steroids. Quantitative analysis for total phenolic content and total flavonoid content of the extract was 0.1±0.005 mg/ml GAE and 0.025±0.003 mg/ml QE respectively. Percent inhibition of α-amylase and α-glucosidase ascertained in presence of extract was 60.42±0.6 and 83.22±0.18 at 0.01 mg while 36.24±0.81 and 37.67±0.15 at 0.005 mg of extracts for both enzymes respectively. Kinetics studies of α-glucosidase inhibition illustrated the non-competitive type of inhibition. TLC autography inhibition patterns were characterized by HR LC-MS. Characterized molecules on docking revealed (6RS)-22-hydroxy-23,24,25,26,27-pentanor-vitamin-D3-6,19-sulfurdioxide-adduct, manoalide and 5β-cholestane-3α,7α,12α,24,25,26-hexol as the best docked molecules with lowest binding energies of-12.5,-11 and-10.2 kcal/mol for α-amylase and-14.2,-11 and-11.2 kcal/mol for α-glucosidase respectively. Conclusion: Results clearly suggested that (6RS)-22-hydroxy-23,24,25,26,27-pentanor-vitamin-D3-6,19-sulfurdioxide-adduct, manoalide and 5β-cholestane-3α,7α,12α,24,25,26-hexol could be considered as lead molecules for the discovery of potent antidiabetic agents