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

Seven compounds [palmitaldehyde (<b>1</b>), daucosterol (<b>2</b>), 24-propylcholesterol (<b>3</b>), asperin (<b>4</b>), vanillic acid (<b>5</b>), paprazine (<b>6</b>), and cycloalliin (<b>7</b>)] were isolated and characterised from aerial part of <i>Allium semenovii</i> 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 <b>6</b> (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 <b>4</b> (IC₅₀ = 108.01 ± 1.99 µM) showed higher acetylcholinesterase enzyme inhibition. Whereas, Compound <b>5</b> was found significant to inhibit tyrosinase enzyme (IC₅₀ = 11.37 ± 0.16 µM). Hence, study suggested therapeutic potential of <i>A. semenovii</i> which could be due to presence of diversified compounds.