Evaluation of in vitro, in silico antidiabetic and antioxidant potential of bioactivity based isolated "Pakistanine" from Berberis baluchistanica

Bioassay based fractionation of methanolic extract of Berberis baluchistanica (Berberi-daceae), used traditionally for internal injuries, led to the isolation of known compounds (1-4). The structure of these compounds was elucidated by different spectroscopic analysis and available literature data. Antidiabetic and antioxidant potentials of B. baluchistanica fractions and isolated compounds were evaluated using in vitro alpha-amylase and DPPH assays. The isolated com-pounds were identified as obamegine (1), pakistanine (2), 8-oxyberberine (3) and baluchistine (4). Obamegine was reported from many other species of this genus but it is first time isolated from B. baluchistanica in present study. Moreover, in vitro pakistanine (2) was found as bioactive lead molecule for hypoglycemic (IC50:40.26 mu g/ml) and antioxidant (IC50:14.15 mu g/ml) activities com-pared to acarbose (IC50:33.68 mu g/ml) and ascorbic acid (IC50:0.41 mu g/ml). To the best of our knowl-edge, no previous data were available for these biological activities. Additionally, in silico antidiabetic and antioxidant activity of pakistanine against two proteins, a-amylase (-9.7 kcal/ mol) and tyrosinase (-8.7 kcal/mol) are reported here for the first time. The molecular docking bind-ing interactions authenticate and support the above-mentioned activities and are helpful in predict-ing the mechanism of action of pakistanine (2). (c) 2022 The Author(s). Published by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).