In vitro antioxidant and enzyme inhibitory properties of Rubus caesius L.

The genus Rubus (Rosaceae) has great potential for and a history of use as natural agents in several traditional folk remedies. Based on this concept, this study focused on the antioxidant activities and enzyme inhibitory effects of extracts and fractions from Rubus caesius. Different chemical assays were performed to detect antioxidant capacity, namely, free radical scavenging (ABTS and DPPH assays), reducing power (CUPRAC and FRAP), phosphomolybdenum and metal chelating. Enzyme inhibitory effects were tested towards cholinesterases (AChE and BChE), tyrosinase, α-amylase and α-glucosidase. In addition, total amounts of phenolics and flavonoids were detected by colorimetric assays. Among the samples, the ethyl acetate fraction exhibited the strongest antioxidant potential with its higher concentration of total phenolics. The highest AChE and α-amylase inhibitory activities were observed in the diethyl ether fraction, while the n-butanol fraction had the strongest anti-tyrosinase inhibitor ability. The present study demonstrated that R. caesius may be considered a source of biologically active compounds to develop novel functional products or drugs in the pharmaceutical field.