Primary metabolites, vitamins and minerals in berry and leaf extracts of black currant (ribes nigrum l.) Under different soil management systems

Abstract

This study examines the effect of soil management system (bare fallow, sawdust mulch and black plastic mulch) on the contents of primary metabolites [individual invert sugars (glucose, fructose, sucrose), organic acids (citric acid, malic acid), vitamins (C, A, B3) and minerals (K, P, Ca, Fe)] in berry and leaf extracts of seven black currant cultivars (Ten Lomond', 'Ben Sarek', 'Tsema', 'Titania', 'Cacanska Crna', 'Tiser and 'Tiben'). High performance liquid chromatography (HPLC) was employed for the identification of individual invert sugars, organic acids and vitamins (A, B3) extracted from berries and leaves. Vitamin C was evaluated by spectrophotometry, and minerals were determined by flame atomic absorption spectrophotometry. Soil management systems and cultivars showed highly significant differences in the levels of the tested parameters. Soil management system had a significant positive effect on the synthesis of primary metabolites, vitamins and minerals in both berries and leaves. The highest values in berry and leaf extracts were obtained by currants grown under sawdust and black plastic mulch, and the lowest by those on bare fallow. Also, the extracts exhibited different characteristics. Berries had a higher content of the tested parameters than leaves. The results indicated that black currant berries and leaves show good adaptability to different soil management systems, and are rich sources of primary metabolites, vitamins and minerals; therefore, they are valuable in terms of human health and as functional food ingredients.