Metabolite profiling, in vitro antioxidant and xanthine oxidase inhibitory properties of six Sumatran sidaguri (Sida L.)

Context: The Sida genus, part of the Malvaceae family, is commonly used in traditional medicine due to its many beneficial properties, such as antigout, anti-rheumatic, anti-inflammatory, antitumor, and hepatoprotective effects. Various species of Sida are found in Indonesia, particularly on the island of Sumatra, and may hold potential for future drug development. Aims: To assess and compare the methanol leaf extracts of three Sida species (S. acuta, S. rhombifolia, and S. cordifolia) from West Sumatra and South Sumatra, Indonesia, for their chemical content in metabolite profiling, in vitro antioxidant capacity, and xanthine oxidase inhibitory activity. Methods: The LC-MS/MS method was used to determine metabolite profiling, while spectrophotometry was used to assess total phenolic content, flavonoid content, antioxidant capacity, and xanthine oxidase inhibitor activity. Results: The results showed that S. rhombifolia (WS) had the highest total phenolic (64.872 ± 1.525 mg GAE/g) and flavonoid contents (13.890 ± 0.816 mg QE/g), S. acuta (SS) exhibited the highest antioxidant activity (IC50 147.295 ± 3.364 µg/mL), and S. cordifolia (WS) showed the highest xanthine oxidase inhibitor activity (IC50 110.087 ± 15.637 µg/mL). Conclusions: These findings suggest that S. acuta, S. rhombifolia, and S. cordifolia may be potential sources of polyphenols and antioxidants and could also serve as promising natural plant sources for developing antigout remedies.