Analytical profiling of vescalagin: Antioxidant Capacity and multi-enzyme inhibition spectrum

Vescalagin have been isolated from Camu-camu (Myrciaria dubia). Vescalagin compound was a found to be the main C-glycosidic ellagitannin with a bridging open ring d -glucose. A variety of techniques were used to assess vescalagin's antioxidant capacity, including its capacity to reduce potassium ferric cyanide, scavenge N,N-dimethyl-p-phenylenediamine dihydrochloride radicals (DMPD•+), scavenge 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulphonate) radicals (ABTS•+), scavenge 1,1-diphenyl-2-picrylhydrazyl radicals (DPPH·), and reduce cupric ions (Cu2+). Likewise, butylated hydroxyanisole (BHA), Trolox, α-tocopherol, and butylated hydroxytoluene (BHT) were employed as reference antioxidants for assessment. For DPPH radical scavenging, vescalagin had an IC50 value of 9.65 μg/mL (r2: 0.9225), while the IC50 values for BHA, BHT, α-Tocopherol, and Trolox were 10.10, 25.95, 11.31, and 7.05 μg/mL properly. The resarch revealed that vescalagin reacted better than BHA, α-tocopherol, and BHT with regard to DPPH· scavenging, but nearly similiar to Trolox. Vescalagin was also shown to be a polyphenolic secondary metabolite that inhibited a number of metabolic enzymes, particularly α-glycosidase, carbonic anhydrases I and II (CA I and II), butyrylcholinesterase (BChE), and acetylcholinesterase (AChE). The Ki values of vescalagin showed 5.87, 3.89, 11.75, 16.23, and 16.08 nM towards AChE, BChE, hCA I, hCA II, and α-glycosidase, respectively. These enzymes are linked to several ilness such as diabetes, Alzheimer disease (AD), epilepsy and glaucoma. The obtained findings clearly indicate that vescalagin can be used as a reference polyphenolic antioxidant or enzyme inhibitor in analytical and screening assays.