Biological activity studies on Klasea serratuloides (DC) Greuter & Wagenitz subsp. karamanica B. Dogan & A. Duran extracts obtained with different extraction methods

The aim of this study was to investigate the antioxidant and enzyme inhibition activities of methanol extracts prepared from Klasea serratuloides (DC) Greuter & Wagenitz subsp. karamanica B. Dogan & A. Duran with Soxhlet, ultrasonic extraction, and maceration methods. 1, 1-Diphenyl-2-picryl hydroxyl (DPPH) quenching assay and 2, 2'-azinobis-3- ethylbenzothiozoline-6-sulfonic acid (ABTS) cation decolorization test were used to evaluate in vitro radical scavenging activity. The total phenolic content was determined with the Folin-Ciocalteu method while the total flavonoid content was evaluated by the aluminum chloride colorimetric method. According to the results, DPPH, ABTS radical scavenging activity and iron chelating activity of methanol of Klasea serratuloides were shown concentration-dependent manner. The extract obtained from maceration was found to be higher than the other extracts. It suggests that the maceration technique was more effective than the other extraction methods for the determination of the phenolic content. The methanol extract of KS using soxhlet (61.17 ± 3.62) and ultrasonic extraction (58.76 ± 1.46) showed higher inhibition than the extract prepared with maceration methods (34.54 ± 0.73) against BChE. All extracts displayed moderate inhibition activity against AChE. As for enzyme inhibition activity, the extract from soxhlet method was found to be more potent tyrosinase, acetylcholinesterase and butyrylcholinesterase inhibitors than the other extracts prepared by ultrasound assisted extraction and maceration methods. The present study suggests that K. serratuloides should be given special attention to conduct further investigation for its phytochemical constituents that attribute to their antioxidant potentials, and enzyme inhibition activities.