Identification and Characterization of Phenolic Compounds in Black Walnut Kernels
Danh C. Vu, Phuc H. Vo, Mark V. Coggeshall, Chung-Ho Lin
Journal of Agricultural and Food Chemistry
Abstract
Black walnuts ( Juglans nigra L.) are highly valued for producing phenolic-enriched nuts. The objectives of this study were to identify and characterize the phenolic contents of 11 different black walnut cultivars and compare the levels of these phenolics between black walnuts and English walnut ( Juglans regia L.). Totally, 16 phenolics including phenolic acids, flavonoids, and catechins were identified in the black walnut kernels, with ellagic acid predominating over the other phenolics. Significant differences were noted for the levels of quinic acid, gallic acid, 1,3,6-trigalloylglucose, catechin, and penta- O-galloyl-β-d-glucose between the studied black walnuts and English walnut. Through principal component analysis, 51.54% of the variance in the phenolic data was explained. The hierarchical cluster analysis results showed three groups to which each walnut sample belongs. Most of the phenolics identified in this study have been reported to exert potential health-promoting activities. The findings of this study will provide critical information for consumers, nutritional therapy practitioners, researchers, and producers.
Extracted Claims
7 claims extracted from this paper into the knowledge graph
ellagic acid predominates phenolic content
“ellagic acid predominating over the other phenolics”
gallic acid differs in levels between black walnuts and English walnut
“significant differences were noted for the levels of quinic acid, gallic acid, 1,3,6-trigalloylglucose, catechin, and penta- O-galloyl-β-d-glucose between the studied black walnuts and English walnut”
phenolic compounds exert health-promoting activities
“Most of the phenolics identified in this study have been reported to exert potential health-promoting activities”