Composition of Phenolic Compounds in South African L. Berries.

The tree is notoriously invasive in most parts of the world, and yet as a pseudospice, its berries potentially possess some significant health benefits which need to be explored. Therefore, polar metabolome of seed + husks (SH), husks (H), and de-hulled (DH) berries were profiled and quantified by untargeted metabolomics approach using UPLC-QTOF-MS. A total of 13 gallotannins, three phenolic acids, a phenolic acid glucoside, three phenolic acid esters, an organic acid, a gallotannin derivative, and nine flavonoids were detected and quantified. Phenolic acids ranged between 12.2-295.7; 4.9-77; and 89.7-1613.1 mg/kg in SH, DH seeds and H respectively. Flavonoids ranged between 1.8-267.5; 73.4-80.4; and 124-564.3 mg/kg in SH, DH seeds and H respectively. Gallotannins ranged between 1.1-146.6; 14.8-21.8; and 48.1-664.8 mg/kg in SH, DH seeds and H respectively. Feruloyltartaric A, quercetin 3-O-glucuronide, catechin digalloylshikimic acid B as well as digalloyl quinic acid were some of the dominant secondary metabolites revealed. These results indicate that berries are a rich source of secondary metabolites with elevated concentrations in the husks, while DH seeds possess lower concentrations to none. These findings open important insights into the potential of berries as a natural source of antioxidants for the food and pharmaceutical industries.