Sinan_2021_Antioxidants.(Basel)_10_1570

The impact of two extraction solvents on the phenolic composition, antioxidant, and enzymes inhibitory and antimicrobial activities of two parts (leaves and stem bark) of P. kotschyi was studied. Two different LC-DAD-MS(n) approaches were used to identify and quantify the bioactive compounds in the different extracts. A total of thirty-two compounds were quantified, being the procyanidin the most abundant in stem bark while catechin and flavonoids are most abundant in leaves. Overall, the stem bark extraction using methanol showed higher amounts of total phenolic (131.83 +/- 1.81 mg GAE/g) and flavanol (14.14 +/- 0.11 mg CE/g) while the leaves extraction using water exhibited stronger levels of total flavonoid (44.95 +/- 0.38 mg RE/g) and phenolic acid (63.58 +/- 2.00 mg CAE/g). As regards the antioxidant assays, methanol stem bark extracts were characterized by the highest antioxidant activities (DPPH: 1.94 +/- 0.01 mmol TE/g, ABTS: 3.31 +/- 0.01 mmol TE/g, FRAP: 2.86 +/- 0.02 mmol TE/g, CUPRAC: 5.09 +/- 0.08 mmol TE/g, phosphomolybdenum: 5.16 +/- 0.23 mmol TE/g and metal chelating: 17.12 +/- 0.46 mg EDTAE/g). In addition, the methanolic extracts of stem bark had highest impact on acetylcholinesterase (2.54 mg GALAE/g), butyrylcholinesterase (5.48 mg GALAE/g). In contrast, the methanolic extracts of leaves was potent against tyrosinase (77.39 +/- 0.21 mg KAE/g) and alpha-glucosidase (0.97 +/- 0.01 mmol ACAE/g), while a higher anti-alpha-amylase (0.97 +/- 0.01 mmol ACAE/g) was observed for water extracts of the same part. All of the tested extracts showed inhibitory effects on elastase, except methanolic leaves extracts. Additionally, the extracts exhibited appreciable antifungal toward A. ochraceus, A. fumigatus, P. ochrochloron, T. viride, and P. funiculosum and promising antibacterial activity against M. flavus, S. aureus, L. monocytogenes, E. coli, P. aeruginosa, E. cloacae, and S. typhimurium. Taken together, the outcomes demonstrated P. kotschyi as a novel source of bioactive molecules of interest with an evident therapeutic value.