In vitro antidiabetic, aphrodisiac and antimicrobial properties of para-propoxybenzoic acid isolated from Acacia auriculiformis A. Cunn Ex. Benth (Fabaceae) stem bark

Abstract

Purpose: To investigate the in vitro antidiabetic, aphrodisiac and antimicrobial properties of parapropoxybenzoic acid isolated from Acacia auriculiformis stem bark. Methods: Powdered dried stem bark of A. auriculiformis was extracted with 70 % ethanol in water and the dried extract obtained was suspended in water and partitioned with ethyl acetate and n-butanol to give their respective soluble fractions. The ethyl acetate fraction being more active, in terms of in-vitro aphrodisiac, antidiabetic and antimicrobial properties, was subjected to chromatographic separation to obtain C1 identified as parapropoxybenzoic acid, which was also evaluated for in-vitro properties using standard procedures. Results: 4-Propoxybenzoic acid showed a weak aphrodisiac property which was not significantly different (p < 0.05) from that of control (normal saline) for all the sexual parameters tested. The compound exhibited antidiabetic activity by dose-dependently inhibiting the actions of α-amylase with half-maximal concentration (IC50) value of 50 ± 0.45 μg/mL. In this regard, it was comparable to that of the standard, acarbose (30 ± 0.18 μg/mL). In the antimicrobial study, a concentration of 200 μg/mL of the compound gave the highest zone of inhibition of 18 ± 0.23 mm against Vibo cholriae (NCTC 5438) Conclusion: The results indicate that the isolated compound, 4-propoxybenzoic, exhibits good antidiabetic and anti- microbial but weak aphrodisiac properties.