Xanthine oxidase inhibitory activity and identification of flavonoid in ethanol extract of sugar apple fruit (Annona squamosa L.).

Nowadays gout is still a problem, both nationally and globally. The most widely used commercial drug to treat gout is allopurinol, which act as xanthin oxidase inhibitor, thus inhibiting uric acid synthesis. However, the use of allopurinol in a relatively long time can cause various unwanted side effects. Previous studies have shown that ethanol extract of sugar apple, which is rich flavonoids can inhibit the xanthine oxidase enzyme, but the structure of flavonoid in this fruit is still unknown yet. The aims of this study are to obtain ethanol extracts from the flesh of sugar apple, purify the extract by partitioning techniques using n-hexane and chloroform solvents, test inhibitory activity against xanthine oxidase and identify the flavonoid content using LC-MS/MS analysis. The results have shown that from 800 g the fruit flesh can be obtained 106 g of concentrated ethanol extract. After purification by partitioning using hexane and chloroform purified ethanol extract ed contained flavonoids, with TPC value of 16.11 ± 0.72 (mgGAE/g) and TFC value of 36.79 ± 2.96 (mgQE/g), in the same volume (0.01 mL) has xanthine oxidase inhibitory power by 75.17% compared to 1 mL of allopurinol 100 ppm and one of the dominant flavonoid compound contained was 3',4',7-trimethoxyflavan. [ABSTRACT FROM AUTHOR]