Phytochemical screening, antioxidant activity and cytotoxic activity of the ethanolic and decoction leaf extracts of Sida rhombifolia L. in Kapai, Lanao Del Sur, Philippines

Many researchers and pharmaceutical corporations are interested in using ethnobotanical studies to generate more effective natural drugs. Finding a novel and less expensive medication to treat cancer is therefore becoming more and more popular. This study aims to investigate the phytochemical components present in the ethanolic and decoction extracts of the leaves of Sida rhombifolia L. a native plant in Kapai, Lanao del Sur, as a basis of the plant’s antioxidant and cytotoxicity activity that is native in Kapai, Lanao del Sur, Philippines. The antioxidant activity of the plant extract was tested through the DPPH scavenging assay and the cytotoxicity activity through the MTT assay. Results of the phytochemical screening showed heavy precipitation of flavonoids, alkaloids, saponins, tannins and steroids in the plant extract. The ethanolic leaf extract exhibited weak antioxidant activity with an IC₅₀ of 153.4 ppm and the decoction extract exhibited very strong antioxidant activity with an IC₅₀ of 30 ppm. Moreover, the results showed a moderately weak cytotoxic activity of the plant extract against HCT-116 cancer cells with an IC₅₀ value of 158.598 µg/ml for ethanolic extract and 279.044 µg/ml for decoction extract. Results indicate that S. rhombifolia can be a potential candidate for further studies on plants with anti-cancer potential.