Impact of different extraction solvents and techniques on the biological activities of Cirsium yildizianum (Asteraceae: Cynareae)

Abstract

Several Cirsium species have been used in folk medicine for the management of human ailments. However, there is a paucity of scientific data regarding their biological activity as in the case of the new species, C. yildizianum, from Anatolia, Turkey. The present study endeavours for the first time to appraise the antioxidant and enzyme inhibitory activity of C. yildizianum. The phytochemical profiles of C. yildizianum extracts obtained using homogeniser-assisted extraction (HAE), ultrasound-assisted extraction (UAE), Soxhlet extraction, maceration, decoction, and infusion, using methanol or water as extraction solvents, was determined by high-performance liquid chromatography with electrospray ionization mass spectrometric detection (HPLC–ESI-MSn) analysis. In all extracts, flavonoids were the most abundant compounds, particularly luteolin and apigenin glycosides. HAE methanol extract presented the highest phenolic (37.10 mg gallic acid equivalent/g) and flavonoid (46.78 mg rutin equivalent/g) contents. Likewise, HAE-methanol extract showed potent radical scavenging (40.76 and 68.13 mg Trolox equivalent [TE]/g, for DPPH and ABTS, respectively) and reducing properties (127.62 and 89.95 mg TE/g, for CUPRAC and FRAP, respectively). HAE-methanol extract showed inhibitory activity against acetylcholinesterase (AChE) (3.57 mg galantamine equivalent [GALAE]/g). UAE-methanol extract was a potent inhibitor of butrylcholinesterase (BChE) (2.72 mg GALAE/g) and tyrosinase (121.06 mg kojic acid equivalent/g) However, poor inhibition was recorded for enzymes targeted in the management of diabetes type II, namely α-amylase and α-glucosidase. On the other hand, potent metal chelating property was observed for water extracts. This study provides comprehensive scientific information on the phytochemical profile of C. yildizianum extracted using different procedures and extraction solvents, which might be considered as valuable baseline data for future bioproducts development. © 2019 Elsevier B.V.