Flavonoid content and radical scavenging activity in fruits of Chinese dwarf cherry (Cerasus humilis) genotypes

Abstract

The Chinese dwarf cherry (Cerasus humilis (Bge.) Sok.) is a small shrub with edible fruits. It is native to northern and western China. This species was included as a medicinal plant in the “Chinese Pharmacopeia” and has emerged as an economically important crop for fresh fruit consumption, processing into juice and wine and nutraceutical products as well. To gain a better understanding of flavonoid biosynthesis and help develop value added products and better cultivars with greater health benefits, we analyzed total flavonoid content (TFC), composition, and radical scavenging activities in fruit extracts of 16 Chinese dwarf cherry genotypes. Fruit peel TFC ranged from 33.5 to 72.8 mg/g RE·FW (RE: rutin equivalent, FW: fresh weight) while fruit flesh TFC ranged from 4.3 to 16.9 mg/g RE·FW. An HPLC analysis revealed that fruit extracts contained 14 flavonoids with considerable variation in their profiles across genotypes. The most abundant flavonoids in most genotypes were proanthocyanidin B1 (PA-B1), proanthocyanidin B2 (PA-B2), phloretin 2′-O-glucoside (PG), and phloretin 2′,4′-O-diglucoside (PDG). Principal component analysis showed that PG, PA-B1, and PA-B2 had large, positive factor loading values in the first principal component for each genotype. Increased scavenging activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals was apparent in genotypes ‘Nongda 4’, ‘Nongda 3’, ‘Nongda 6’, ‘Wenfenli’, and ’10-32’, suggesting promising applications in the production of nutraceutical products. In summary, our results will aid in breeding, fruit processing, and developing medicinal uses of the Chinese dwarf cherry.