Comparative in vitro studies of the biological potential and chemical composition of stems, leaves and berries Aronia melanocarpa's extracts obtained by subcritical water extraction

Preparation of functional products as well as natural-based products requires non-toxic but effective extraction techniques. In this study, subcritical water extraction was used for the extraction of different aronia parts in order to explore their potential. Stems, leaves and berries of Aronia melanocarpa were extracted under the following conditions: temperature 130 °C; pressure 35 bar; time 20 min. The total phenols and flavonoid contents of the produced extracts were evaluated by conventional spectrophotometric methods. Additionally, the main phenolic compounds were also identified and quantified by high performance liquid chromatography with diode array detection (HPLC-DAD). The biological potential of the extracts was evaluated by determining their antioxidant (DPPH, ABTS and lipid peroxidation assays), antimicrobial, enzyme inhibitory (cholinesterase and elastase) and cytotoxic effects (HeLa, A-549, LS-174T, MRC-5 cell lines). The results indicate that leaves and berries extracts exhibited stronger antioxidant action when compared with stems. The strongest cholinesterase and elastase inhibitory activity was also found in berries extract. Similarly, the extracts obtained from leaves and berries showed considerable cytotoxic effects against tested cell lines. A moderate antimicrobial effects was observed too. Demonstrated biological potential of all three aronia parts can trace a new road map for developing newly designed functional products.