Valorization of the antioxidant, enzyme inhibition and phytochemical propensities of Berberis calliobotrys Bien. ex Koehne: A multifunctional approach to probe for bioactive natural products

Chemical composition and pharmacological effects of different extracts of Berberis calliobotrys Bien. ex Koehne were studied. The chemical profile of the methanol, ethyl acetate, n-butanol and aqueous extracts were established by determining their total phenolic and flavonoid contents, besides ultra-high performance liquid chromatography mass spectrometry (UHPLC-MS) of methanol and ethyl acetate extract of Berberis calliobotrys. Antioxidant potential of the extracts was evaluated as inhibition of 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and 2, 2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid (ABTS) free radicals, by reducing power via ferric reducing antioxidant power (FRAP), by cupric reducing antioxidant capacity (CUPRAC), and by phosphomolybdenum and metal chelation assays. Enzyme inhibitory potential of the extracts was also tested against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), α-glucosidase, α-amylase and tyrosinase. The Bc-W (Berberis calliobotrys aqueous extract) and Bc-M (B. calliobotrys methanol extract) afforded highest phenolic contents with values of 94.34 and 77.70 mgGAE/g extract, respectively, while the Bc-E (Berberis calliobotrys ethyl acetate extract) contained highest flavonoid contents (11.11 mg RE/g extract). UHPLC-MS analysis of Bc-M and Bc-E showed the presence of known secondary metabolites of alkaloid, phenolic, flavonoid, and terpene classes. The Bc-W was the most active in the ABTS, CUPRAC, FRAP and phosphomolybdenum antioxidant assays, whereas for DPPH and metal chelation activities, Bc-M was found to be more potent. The Bc-E and Bc-B (Berberis calliobotrys n-butanol extract) were least active for antioxidant potential. All the extracts showed considerable cholinesterase inhibition, whereas, Bc-E was most potent inhibitor of α-amylase, α-glucosidase and tyrosinase. It is concluded that B. calliobotrys extracts contained variety of bioactive constituents; antioxidant and enzyme inhibitors thus can be considered as a potential candidate for relevant industrial applications.