Multidirectional approaches on autofermented chamomile ligulate flowers: Antioxidant, antimicrobial, cytotoxic and enzyme inhibitory effects

In the frame of the present paper the enzymatic transformation of apigenin-glucosides into free aglycone was achieved by autofermentation of chamomile ligulate flowers (CLF). Antioxidant properties of the autofermented CLF (A-CLF) extract were evaluated by their radical scavenging activity against hydroxyl radicals and inhibition of lipid peroxidation. Obtained results showed that A-CLF extract in a concentration of 0.84 mg/mL was able to inhibit 50% of hydroxyl radicals, while IC50 value in the case of inhibition of lipid peroxidation was 5.21 mg/mL. Antimicrobial activity was done by measuring minimal inhibitory concentration (MIC) values for eight microbial strains. Obtained MIC values (9.75-156.25 mu g/mL) confirmed high antibacterial and antifungal activities of the extract. Cytotoxic activity was done by using three histological different cell lines: Hep2C; RD and L2OB. Obtained IC50 values for these cell lines were: 28.72; 17.31 and 10.92, respectively. Furthermore, in vitro investigation of the A-CLF ability to inhibit selected enzymes (alpha-amylase, alpha-glucosidase, tyrosinase) was done as well. Determined activities against alpha-amylase and alpha-glucosidase were 0.94 and 3.24 mmol ACAE/g, respectively. Further, measured activity against tyrosinase was 0.69 mg KAEs/g indicating high enzyme-inhibitory activity of examined sample. Results demonstrated that A-CLF extracts showed considerable pharmacological activity. (c) 2018 SAAB. Published by Elsevier B.V. All rights reserved.