Antioxidant and Antimicrobial Activities of Methanolic Extracts of Scorodocarpus borneensis Becc

Abstract

Yohana Sutiknyawati Kusuma Dewi, Cico Jhon Karunia Simamora, Dzul Fadly.

Local communities in Borneo island usually use Scorodocarpus borneensis Becc. (known as Kulim tree) to prevent a deterioration of oil and meat. This study aims to find out the preservatives mechanism by identifying the total phenolic, antioxidant, and antimicrobial capabilities of S. borneensis. In this study, the phenolic compounds of the leaf, stem bark, and fruit were extracted by 70 % methanol before subjected to the antioxidant activity determined by the DPPH method. The antimicrobial activities were determined toward a sample extract possessed the highest antioxidant activities, by the well diffusion method against bacterial cultures and inhibitory proteolytic bacteria method in red tilapia fillet. The results showed that the phenolic compounds' value varied from 30.83 ± 3.3 to 52.93 ± 4.0 mg GAE/g. The highest antioxidant activity was identified from the leaf, followed by stem bark and fruit, with an IC50 value of 36.88 ppm, 52.45 ppm, and 86.20 ppm, respectively. This methanol extract of S. borneensis leaf played a role as an inhibitory against MRSA bacteria as a Gram-positive bacterium. While also inhibit the growth of Salmonella typhii and Candida albicans. The extract of Kulim's leaf contained many bacteriostatic bioactive compounds, which can be used to maintain bacteria's proteolytic population in tilapia fillets. The study suggests that the methanolic extract of Scorodocarpus borneensis Becc exhibits an excellent potential for antioxidant and antimicrobial activities and may be useful as a natural preservative.