Purpose: To investigate the in vitro anticholinesterase, α-glucosidase and antioxidant activities of α-spinasterol isolated from Acacia auriculiformis leaves.Methods: The powdered leaves of Acacia auriculiformis were extracted with 70 % ethanol and the dried hydroalcoholic extract was suspended in water and partitioned with ethyl acetate and n-butanol to give their soluble fractions. The in vitro inhibitory activities of α-spinasterol were determined against cholinesterase and, α-glucosidase enzymes, and free radical scavenging potentials using (1,1-diphenyl-2-picrylhydarzyl (DPPH) and 2,2-azino-bis (3-Ethylbenzothiazoline-6-sulphonic acid (ABTS) antioxidantassays.Results: The compound, α-spinasterol, exhibited moderate anticholinesterase activity (IC50 value of 44.19±2.59 μg/mL which was significantly  different at (p < 0.05) when compared to the standard galanthamine (IC50 value of 1.73 ± 1.10 μg/mL). It also displayed a good α-glucosidase  inhibitory activity with IC``` value of 8.65 ± 1.71μg/mL which was not significantly different when compared to the standard, acarbose with IC50 value of 2.79±0.81 μg/mL. This compound, however, exhibited weak free radical scavenging activities at 26.93 ± 0.00 and 35.16 ±.0.26 % inhibition of DPPH+ and ABTS+ radicals as compared to ascorbic acid and Trolox (73.88 ± 0.04 and 99.82 ± 0.00%) respectively.Conclusion: The results show that α-spinasterol isolated from Acacia auriculiformis exerts potent inhibitory effect against cholinesterase enzyme which might serve as a lead in the search for drugs against Alzheimer disease and diabetes mellitus. Keywords: Acacia auriculiformis, α-Spinasterol, Galanthamine, Acarbose, Trolox, Ascorbic acid

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Three new isomeric corniculatolides (1, 2, and 3) with an unusual caffrane and isocorniculane framework, and five known metabolites were isolated from the chloroform extract of the stems of Xylocarpus granatum. The structures of the new metabolites were deduced as corniculatolide B (1), isocorniculatolide B (2), and corniculatolide C (3) by spectroscopic data analysis and a combination of chemical transformations and supported by single-crystal X-ray crystallographic data of 1 and 3. The isolated compounds were evaluated for their in vitro cytotoxicity and α-glucosidase (Saccharomyces cerevisiae) inhibitory potential. Compound 3 possessed α-glucosidase inhibitory activity with an IC 50 value of 24.8 μM, whereas these rare macrolides showed no effect on the mammalian cancer cell lines MIAPaCa-2, DU145, MCF-7, and HTC-116.