2,011
Views
21
CrossRef citations to date
0
Altmetric
Original Articles

Phenolic profiles and cellular antioxidant activity of longan pulp of 24 representative Chinese cultivars

, , , , , , , , & show all
Pages 746-759 | Received 31 Jul 2017, Accepted 05 Jan 2018, Published online: 04 May 2018
 

ABSTRACT

The phytochemical composition and antioxidant activity of fruits are associated with their health benefits. Longan is a traditional Chinese edible and medicinal fruit, but its varietal differences in phytochemical profiles and antioxidant activity were unknown. Twenty-four longan cultivars from southern China were investigated in this study. Their total phenolic and flavonoid contents in pulp were 22.09–132.47 mg gallic acid equivalents/100 g and 2.48–14.26 mg catechin equivalents/100 g, respectively. The mean contributions of free phenolics and flavonoids to the total were 82.5% and 94.0%, respectively. Among 10 individual phenolics detected by HPLC, the contents of epicatechin, 4-methylcatechol, chlorogenic, and vanillic acids were relatively higher. The cellular antioxidant activity (CAA) of longan pulp showed significant varietal discrepancies and positive correlation with phenolic and flavonoid contents. Phenolics in longan pulp of 24 cultivars showed lower CAA potential than many other fruits with the CAA qualities from 0.35 to 1.21 µmol quercetin equivalent/100 µmol total phenolics. Longan cultivars were classified into six groups by hierarchical clustering analysis. Six cultivars in group 4 and 6 had higher phytochemical contents and CAA activity.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China (Grant No. 31571828), the Guangdong Provincial Science and Technology Projects (Grant No. 2013B091500076 and 2016B070701012), the Guangzhou Municipal Major Project of Science and Technology for People’s Livelihood (Grant No. 201704020039), and the Pearl River S&T Nova Program of Guangzhou (Grant No. 201506010028). The authors declare that there are no conflicts of interest.