Commercial quality, major bioactive compound content and antioxidant capacity of 12 cultivars of loquat (Eriobotrya japonica Lindl.) fruits.

BACKGROUND: Modern consumers are increasingly interested in their personal health and expect the food they purchase to be tasty and attractive while being safe and healthful. The aim of this study was to determine the commercial quality, characterise the antioxidant capacity and quantify the major bioactive compounds of 12 cultivars of loquat fruits in order to establish a database for utilising these germplasm resources.
RESULTS: Of the 12 cultivars, 'Guanyu' produced the biggest fruits, while 'Tianzhong' and 'Bingtangzhong' had the highest soluble solids content but the lowest titratable acidity. 'Taipinghong' was reddest in colour. Sucrose, fructose, glucose and sorbitol were the major sugars in loquat fruits, with the highest total sugar content being observed in 'Bingtangzhong' and 'Tianzhong'. Phenolics and flavonoids were the main bioactive compounds and were abundant in 'Tianzhong' and 'Zhaozhong'. 'Taipinghong' had the highest total carotenoid content, while 'Qingzhong' had the highest vitamin C content. 'Tianzhong', 'Bingtangzhong' and 'Ninghaibai' showed higher antioxidant activity than the other cultivars, as measured by assays of 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2-azino-bis(3-ethylbenzthiozoline-6-sulfonic acid) (ABTS) scavenging and ferric-reducing/antioxidant power (FRAP).
CONCLUSION: Commercial fruit quality, major bioactive compound content and antioxidant capacity varied greatly among the 12 cultivars. 'Bingtangzhong' and 'Tianzhong' were the highest-ranking cultivars based on their good commercial quality and high nutritional value. The loquat fruits with higher total phenolic and flavonoid contents also had clearly higher antioxidant capacities.