ZHU Xiaoting, XIAO Gengsheng, CHEN Hui, YU Yuanshan, WEN Jing, ZOU Bo, XU Yujuan, FU Manqin
This study aimed to examine the dynamics of active components in both organic (O) and non-organic (N) Gonggan Mandarin (GM) fruits at different ripening stages.The primary phenolic compounds and antioxidant activities present in the peel, pomace, seeds, and juice of GM were analyzed using high-performance liquid chromatography (HPLC).Additionally, a correlation analysis was conducted employing Pearson's method.Results indicated that the total phenols content, total flavonoids content, DPPH radical scavenging capacity, ABTS cationic radical scavenging capacity, and ferric ion reducing antioxidant power (FRAP) of both OGM and NGM fruits exhibited decreases of 32.58% and 34.76%, 35.47% and 37.78%, 31.90% and 25.05%, 30.27% and 34.54%, as well as 27.06% and 25.04%, respectively, from September to January of the following year.The total phenols content, total flavonoids content, DPPH radical scavenging capacity, ABTS cationic radical scavenging capacity, and FRAP of OGM fruits were higher than those of NGM fruits at different maturity stages by 5.48%-9.00%, 3.37%-9.64%, 5.88%-16.52%, 2.96%-10.84% and 2.62%-8.98%, respectively.The total phenolic and flavonoid contents, as well as the antioxidant activities (DPPH radical scavenging capacity, ABTS cationic radical scavenging capacity, and FRAP), of different parts, were ranked in the following order:fruit peel>pomace>seeds>juice.Hesperidin is the predominant phenolic compound found in the fruit of GM.Correlation analysis revealed that gallic acid, chlorogenic acid, ferulic acid, epicatechin, rutin, naringin, neohesperidin, methyl hesperidin, didymin, hesperitin, genistein, apigenin, sinensetin, tangeretin, nobiletin, total phenols, and total flavonoids exhibited a positive correlation with antioxidant activities as measured by DPPH radical scavenging capacity, ABTS cationic radical scavenging capacity, and FRAP assays.This study elucidated the phenolic properties and variations of OGM and NGM fruits at different ripening stages, thereby establishing a foundation for the processing and utilization of various parts of gomphocarp fruits as a significant dietary source of antioxidants.