To investigate the anti-obesity potential of Antidesma bunius L. (MM), a Thai local fruit which is named "Mao Luang," we have focused on the effects on pancreatic α-amylase and lipase enzyme activity and on adipocyte life cycle using the 3T3-L1 cell line as a model. In addition, the phytochemical composition and anti-oxidation potential were also analyzed using HPLC-PDA UV and colorimetric methods. The ethanolic extract of MM fruits prepared by a maceration method was used in the experiments. MM extract, yield 12.08% w/w, is composed primarily of phenolics and anthocyanins as the major phytochemicals, among which, gallic acid, catechin, anthocyanin-3-glucoside, and protocatechuic acid were initially identified. In addition, susceptibly inhibitory effects on oxidation in a DPPH assay; on lipase enzyme activity rather than amylase enzyme; and on adipocyte adipogenesis of MM were demonstrated. Interestingly, a concentration-dependent bi-modular manner of activity on adipocyte adipogenesis was discovered, whereby a significant anti-adipogenic effect was demonstrated at high concentration, whilst low concentrations of MM showed adipogenic induction. Lipolytic induction was manifested. Conclusively, the ethanolic MM extract was discovered to be a potential anti-obesity agent contributed by inhibitory effects on lipase enzyme and anti-differentiation and -adipogenesis in adipocytes which significantly correlated to the total phenolics content, as well as anti-oxidation as the mechanism of action. Nevertheless, to achieve effective application, further investigation in in vivo models should be considered.
Keywords: Antidesma bunius L.; adipocyte; anti-adipogenesis; anti-obesity; pancreatic lipase; α-amylase.