Phytochemical Analysis and Antioxidant and Alpha-glucosidase Inhibitory Activities of the Stem Bark of Dialium cochinchinense Pierre

Abstract

The purpose of this study was to determine the phytochemical compositions and to evaluate the biological activity of the stem bark of Dialium cochinchinense. The phytochemical analysis showed the presence of steroids, terpenoids, anthraquinones, saponins, and phenolics in the stem bark of D. cochinchinense. The optimal extraction conditions were 70% ethanol at 30°C for 40min with a material/solvent ratio of 1/20. Under the optimal conditions, the corresponding predicted response value for the total phenolic content was 100.80 ± 0.40 mg GAE/g DW. The evaluation of antioxidant activity indicated that the polyphenol-rich extract was a good source of antioxidants as measured by the DPPH assay with the IC50 of 3.81 ± 0.58 μg mL-1. The extract also demonstrated a strong a-glucosidase inhibitory activity with the IC50 value of 2.14 ± 0.05 μg/mL. Therefore, D. cochinchinense could be useful as a potential preventive intervention for free radicals in mediated diseases as well as an antioxidant drug and a potential source in treating diabetes mellitus in the pharmaceutical industry.