Abstract:

Shorea roxburghii or locally known as ‘meranti temak nipis’ is one of the many species of Shorea found in Malaysian forest. The species which come from Dipterocarpaceae family is known to contain resveratrol oligomers, a group of plant secondary metabolites that showed various biological activities [1]. In this study, phytochemical investigation was carried on the stem bark of Shorea roxburghii collected from FRIM Mata Ayer, in Perlis. The stem bark of S. roxburghii was extracted exhaustively with acetone at room temperature. Purification of the crude acetone extract using various chromatographic techniques lead to the isolation of a tetramer resveratrol which was identified as hopeaphenol. The structures of the isolated compound was elucidated based on spectroscopic methods (IR, 1D and 2D NMR) and comparison with literature [2]. The crude extract of Shorea roxburghii and the isolated compound were also tested for antibacterial activity against 4 types of bacteria (MRSA, S. aureus, E.coli and S. dysenteriae) using Kirby Baueur disc diffusion method. Results showed that the crude extract gave a resistant response with zone inhibition of 10 mm for MRSA whereas the isolated compound gave a zone inhibition of 7 mm for bacteria S. Dysenteriae. The antioxidant activity of the isolate was evaluated using DPPH assay and was found to exhibit 91.08 % inhibition which is comparable to synthetic antioxidant, BHT which was 93.93%.