Phytochemical and Xanthine Oxidase Inhibitory Activity in Nypa fruticans Wurmb. Fruit Extracts

Abstract

Thai wisdom knows the benefits of mangrove palm fruits to be boiled in water and drink as herbal medicines for healing gout. However, there is no scientific paper to confirm the relief of gout symptoms by mangrove palm, this is the first report. The mangrove palm: exocarp/mesocarp, endocarp, endosperm, and the whole of fruit in the ripe stage were extracted with water and ethanol. The crude extracts were studied for the phytochemical and inhibitory activity of xanthine oxidase, one of the causes of gout. Most of the crude extracts showed similar phytochemicals as, phenolic compounds, flavonoids, terpenoids, and steroids, but there was no alkaloid, anthraquinone, and iridoid glycoside. The endocarp extracted with ethanol showed the highest phenolic content (102.85±5.73 mg GAE/g), flavonoid content (531.02±10.46 mg QUE/g), and strongest antioxidant activity (26.79±0.57 mg VCE/g). The ethanolic and water extract (heating at 60 °C) of endocarp showed the strongly inhibited xanthine oxidase activity with IC50 of 0.029±0.001 mg/mL and 0.14±0.04 mg/mL, respectively. Therefore, this research has already confirmed that the fruit of mangrove palm could inhibit xanthine oxidase enzyme. It would be useful for further development as an herbal medicine or supplementary food for gout likely in the form of hot brewed teas or products that are safe for consumers. Moreover, it also adds value to the peel of the leftovers from consumption.