Optimization of Primary Metabolites and Antimicrobial Activity in Aronia Berries as Affected by Soil Cultivation Systems

Abstract

This study was aimed at optimizing primary metabolites (sugars, acids, vitamins, and minerals) and testing antimicrobial activity in the berries of aronia (Aronia melanocarpa [Michx.] Elliott) cv. ‘Nero’ grown using black foil mulch and without mulch (bare soil). Soil cultivation systems showed significant effect on the tested parameters. Black foil mulch allowed early soil warming and caused an increase in soil temperature and moisture during the growing season, thus promoting the synthesis of soluble solids, sugars (total sugars and individual invert sugars), protein, microelement iron and vitamin A. In contrast, bare soil, with lower soil water regimen and temperature, directly led to an increase in acids (total acids, pH, organic acids), macroelements (potassium, calcium, phosphorus, magnesium, and sodium) and vitamins C and B3 in aronia berries. Soil cultivation systems did not have a significant effect on the synthesis of vitamins B1 or B2 or of microelements copper, zinc, or molybdenum. Glucose was the dominant individual invert sugar in all berry extracts, followed by fructose, while the amount of sucrose was very low. In terms of organic acids, the main organic acid was malic acid, whereas lower quantities of citric acid were found. Antimicrobial activity varied from 19.31 to 143.23 μg/ml depending on the soil cultivation system. The results indicate that aronia can be grown on foil-mulched soils and that foil mulch had a significant effect on the synthesis and accumulation of certain primary metabolites and antimicrobial activity in aronia berries.