Abstract:

In this study, the in vitro antioxidant effect of the 80% ethanol extract from Gongshui white pomelo peel was assessed and compared with those of the 80% ethanol extract from ponkan peel, VC, propyl gallate (PG). The results were showed that the scavenging abilities of the 80% ethanol extract (supernatant) from ponkan peel, VC and PG against hydroxyl free radicals trapped with salicylic acid were 5.515 and 1.320 times higher and 0.428 lower than that of the 80% ethanol extract (supernatant) from Gongshui white pomelo peel, while the freeze dried crystal of 80% ethanol extract from ponkan peel, VC and PG were 17.407 and 1.586 times higher and 0.514 times lower than that of the freeze dried crystal of 80% ethanol extract from Gongshui white pomelo peel, respectively. The scavenging abilities of the 80% ethanol extract from ponkan peel, PG and VC against hydroxyl free radicals generated in Fe2+/H2O2 reaction system were 18.416, 4.820 and 1.716 times higher than that of the 80% ethanol extract from Gongshui white pomelo peel, and the hydroxyl free radical scavenging abilities of the freeze dried crystal of 80% ethanol extract from ponkan peel, PG and VC were 6.589, 3.609 and 1.285 times higher than that of the freeze dried crystal of 80% ethanol extract from Gongshui white pomelo peel, respectively. In superoxide anion free radical scavenging ability, the 80% ethanol extract from ponkan peel, PG and VC were 13.941, 1.059 and 2.442 higher than the 80% ethanol extract from Gongshui white pomelo peel and the freeze dried crystal of 80% ethanol extract from ponkan peel, PG and VC were 5.908, 1.471 and 3.392 times higher than the freeze dried crystal of 80% ethanol extract from Gongshui white pomelo peel. The 80% ethanol extract from Gongshui white pomelo peel had the potential to reduce ferric ions, but its reducing power was weaker than those of 80% ethanol extract from ponkan peel, VC and PG.

Key words: Gongshui white pomelo, ponkan, antioxidation, hydroxy radical, superoxide anion radical, reducing power