AKTIVITAS ANTIOKSIDAN DAN ANTIBAKTERI EKSTRAK DAUN KESAMBI (SCHLEICHERA OLEOSA (LOUR.) OKEN) TERHADAP ESCHERICHIA COLI BERDASARKAN PERBEDAAN KEPOLARAN PELARUT

Abstract

Kesambi leaves (Schleichera oleosa), from the Sapindaceae family, have long been used as traditional medicine with various reported pharmacological potentials. This study examined how extraction solvent polarity (methanol vs. n-hexane) affects the antioxidant (DPPH method) and antibacterial activity of kesambi leaves. Extraction was done by maceration, followed by phytochemical screening and antioxidant/antibacterial testing. The methanol extract yield (28%) was much higher than the n-hexane extract (1.31%), with simplicia moisture content of 3.7%, meeting Indonesian Herbal Pharmacopoeia standards. Phytochemical screening showed the methanol extract contained alkaloids, tannins, steroids, and saponins, while the n-hexane extract contained alkaloids, tannins, and steroids. The methanol extract exhibited strong antioxidant activity (IC50 = 61.847 ppm), outperforming the n-hexane extract, which was weak (IC50 = 205.757 ppm), compared to vitamin C as the positive control (IC50 = 13.755 ppm). In antibacterial testing, both extracts inhibited E. coli, with the methanol extract producing a larger inhibition zone, though both remained weak relative to amoxicillin as the positive control. Overall, the polar solvent (methanol) yielded better antioxidant and antibacterial results than the nonpolar solvent (n-hexane), suggesting methanol extraction is more effective for harnessing kesambi leaves' bioactive compounds.