Isolation and characterisation of acetylcholinesterase, tyrosinase enzyme, and free radical inhibitors from aerial part of Allium semenovii Regel

Seven compounds [palmitaldehyde (1), daucosterol (2), 24-propylcholesterol (3), asperin (4), vanillic acid (5), paprazine (6), and cycloalliin (7)] were isolated and characterised from aerial part of Allium semenovii Regel for the first time. Extract, fractions, and isolated compounds were assessed for antioxidant, acetylcholinesterase and tyrosinase enzyme inhibition activities. A maximum antioxidant potential was observed in compound 6 (IC50 =12.45 ± 0.69 µM, ABTS•+ and 377.67 ± 0.10 µM, DPPH•) followed by ethyl acetate (IC50 = 95.00 ± 0.15 µg/mL, ABTS•+) and chloroform fraction (IC50 = 370.00 ± 0.6 2 µg/mL, DPPH•). Chloroform fraction (IC50 = 172.50 ± 0.70 µg/mL) and compound 4 (IC50 = 108.01 ± 1.99 µM) showed higher acetylcholinesterase enzyme inhibition. Whereas, Compound 5 was found significant to inhibit tyrosinase enzyme (IC50 = 11.37 ± 0.16 µM). Hence, study suggested therapeutic potential of A. semenovii which could be due to presence of diversified compounds.