Chemical properties of black currant (Ribes nigrum L.) berry and leaf extracts

Abstract

The objective of this experiment was to identify and quantify individual invert sugars (glucose, fructose, sucrose) organic acids (citric acid, malic acid), total anthocyanins, anthocyanin glycosides (delphinidin 3-glucoside, delphinidin 3-rutinoside, cyanidin 3-glucoside, cyanidin 3-rutinoside), vitamins (C, A, B3) and minerals (K, Ca; Mg, Na, P, Cu, Zn, Fe) in berry and leaf extracts of black currant. The extracts prepared from black currant leaves and berries exhibited different characteristics. Berries had higher contents of the tested parameters compared to leaves. Fructose was the dominant invert sugar in all extracts, followed by glucose, while the amount of sucrose was very low. Berry extracts contained 4.35 times more fructose than leaf extracts, and glucose was 3.92 times higher in berries than in leaves. The main organic acid was citric acid, whereas twice as low quantities of malic acid were observed in all tested berries and leaves. The content of total anthocyanins ranged from 289.2 to 12.3 mg C3G 100 g-1 in berry and leaf extracts, respectively. In the present research, cyanidin-3-rutinoside was the most abundant anthocyanin in both berries and leaves. The major vitamin in the tested black currant was vitamin C (213.5 and 38.7 mg 100 g-1, respectively), whereas the most abundant mineral was K (328.1 and 20.3 mg 100 g-1, respectively). The results suggested that black currant berries and leaves can be used as valuable ingredients for functional foods.