Polyphenolic Profile and Antioxidant Activity of Juglans regia L. Leaves and Husk Extracts

Abstract

The aim of this study is to characterize the antioxidant capacity and establish the profile of polyphenolic compounds in walnut extracts (different extracts prepared from walnut leaf and green husks). The correlation between bioingredients of the product tested and their ability to scavenge free radicals and reduce them by chelating various metal ions were examined. Research technology combining TG (thermogravimetry), FTIR (Fourier-transform infrared spectroscopy), high-performance liquid chromatography system (HPLC) with electrochemical methods (cyclic and differential pulse voltammetry) and spectrophotometric methods (ABTS, FRAP, and DPPH assays) was used to rate the potential oxidation-reduction components of walnut extracts. A high affinity for scavenging free radicals ABTS and DPPH was found for natural substances present in leaves and green husks. The walnut is beneficial to health as it contains alpha-linolenic acid in its lipid fraction and, as demonstrated in this study, its husks are rich in polyphenolics with high antioxidant capacity.