Phytochemical analysis, biological activities and molecular docking studies of black and white goji fruits of Lycium ruthenicum Murray

Abstract

This study analyzes the phenolic and phenylamide composition of black and white goji berries, identifying 31 phenolics, 28 phenylamides, and 3 organic acids. Black berries contained about 10-fold higher phenolics, particularly hydroxybenzoic acid derivatives and anthocyanins, while white berries were dominated by phenolic acids and glycosylated spermidine/spermine derivatives. Glycosides of myricetin and laricitrin in black berries and caffeoyl putrescine monohexosides in both types, were identified. Phenylamide profiles differed, with N-caffeoyl-N′-dihydrocaffeoyl spermidine as the most abundant and bioactive. Both extracts showed antioxidant and enzyme-inhibitory effects. Black goji displayed stronger tyrosinase inhibition consistent with its high phenolic content and synergism among phenolics and phenylamides. Molecular docking revealed strong interactions with AChE and tyrosinase, especially for N-caffeoyl-N′-dihydrocaffeoyl spermidine, which showed higher affinity for tyrosinase than standard inhibitors. The presence of sugar moieties in some compounds reduced binding stability. These results highlight goji berries as promising sources of bioactives, for functional foods and nutraceuticals