Hepatoprotective, cytotoxic, antimicrobial and antioxidant activities of Dioon spinulosum leaves Dyer Ex Eichler and its isolated secondary metabolites.

Given the lack of adequate research on Dioon spinulosum (D. spinulosum) Dyer Ex Eichler, this study was conducted focusing on different biological activities and phytochemical investigation of D. spinulosum for the first time. D. spinulosum showed strong protective activity against DNA damage and potent activity against VERO cell line. It also presented antimicrobial and hepatoprotective activity. Phytochemical investigation of the leaves resulted in isolation of two new flavonoids, apigenin 7-O-α-d-glucopyranoside (15) and amentoflavone 7-O-α-l-rhamnopyranoside (16), in addition to fifteen known compounds: phytone (1), trans-phytol (2), β-sitosterol (3), stigmasterol (4), oliveriflavone (5), 7,4',7″,4″'-tetramethylamentoflavone (6), 7,4',7''-trimethylamentoflavone (7), scaidopitysin (8), bilobetin (9), isoginkgetin (10), aromadendrin (11), sotusflavone (12), engeletin (14) and eriocitrin (17) for the first time together with amentoflavone (13). Compounds (11) and (13) displayed very strong cytotoxic activity and showed the highest protective activity against DNA damage.