Cytotoxicity and antioxidant properties of the methanol extracts of leaves and flowers of Cornus mas and Cotinus coggygria were studied, together with their chemical composition. Extracts of C. coggygria flowers and leaves showed better antioxidant activity in reaction with 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical as well as in inhibition of lipid peroxidation (LP) than C. mas extracts. Preliminary results showed that all extracts possessed potential cytotoxic activity towards HeLa and LS174 human cancer cell lines in vitro, with stronger inhibition against growth of HeLa cell growth than against LS174 cell growth. Cytotoxic activity of C. coggygria extracts showed good correlation with their antioxidative activity in vitro. In the brine shrimp lethality test, there were no significant changes in toxicity.
Bilberry fruits (Vaccinium myrtillus L.) are one of the richest natural sources of anthocyanins and are widely used due to their pharmacological and nutritional properties. To ensure their maximum application potential, it is necessary to overcome the limitations of conventional extraction solvents and techniques. This study aimed to develop a green method for bilberry anthocyanin extraction using natural deep eutectic solvents (NaDES) integrated with ultrasound-assisted extraction (UAE) in order to define extraction conditions that will prevent decomposition of the anthocyanins or the loss of bioactivity. After a screening of ten different NaDES, choline chloride:sorbitol (1:1) was selected as the most effective. Furthermore, the influence analysis and optimization of the NaDES–UAE extraction conditions were carried out employing response surface methodology. The optimal conditions were found to be an extraction time of 37.63 min, a temperature of 48.38 °C, and 34.79% (w/w) water in NaDES. The extraction yields of target compounds under optimized extraction conditions were 0.27 mg/g DW of cyanidin-3-O-glucoside and 2.12 mg CGE/g DW of TAC. The obtained optimized extract showed promising radical scavenging and antimicrobial activity. A stability study with the optimized extract revealed that refrigerated storage at 4 °C in the dark provided the best anthocyanins preservation. Overall, the developed NaDES-UAE method showed promising application potential and can be considered as a high-efficiency green alternative to conventional anthocyanins extraction methods, enabling the preservation of active ingredients and the bioactivity of extracts.