Longan is widely consumed due to its high nutritional value. The growing area has substantial effect on nutrient component and secondary metabolism of fruits. The aim of this study was to analyze the differences in physicochemical characteristics, polyphenol profiles, and antioxidant activity of longan fruits grown in four regions of China. Two representative cultivars 'Shixia' and 'Chuliang' located in Chongqing, Guanxi, Zhanjiang and Hainan were collected and analyzed. The results showed that the fruit weights, edible rates, and total soluble solids were 5.63-12.57 g, 52.7-68.7% and 17.54-23.68%, respectively. The titratable acids, reducing sugars, vitamin C contents were 0.22-0.62%, 2.27-5.55% and 68.29-157.34 mg/100 g, respectively. Interestingly, contents of total polyphenols and antioxidant activities in longan pericarps from Chongqing were higher than those from low-latitude regions for two cultivars. In addition, 10 polyphenols were detected by UPLC-QqQ-MS/MS which showed that the content of polyphenols was much higher in longan pericarps than in pulps. The content of polyphenol profiles in longan was mainly influenced by its tissue distribution. Cultivar type may also affect the polyphenol profile of longan.
Keywords: Antioxidant capacities; Latitude; Nutritional values; Phenolic profile; UPLC–QqQ-MS/MS.
© 2023. The Author(s), under exclusive licence to The Japan Society for Analytical Chemistry.