BRAZILIN FROM STEM OF Caesalpinia bahamensis subsp. orientensis. IN VITRO ANTIBACTERIAL ACTIVITY AND IN SILICO BIOPROSPECTING OF THEIR OXIDATION PRODUCT

Abstract

Brazilin was isolated as the major secondary metabolite from the ethanolic extract of the wood of the subspecies Caesalpinia bahamensis subsp. orientensis. Its structure was established by analyzing 1D and 2D NMR spectroscopic data and HRESIMS. The evaluation of the in vitro antibacterial activity of the ethanolic, chloroformic and ethyl acetate extracts against strains of Staphylococcus aureus (ATCC 6538) and Escherichia coli (ATCC 8739), reveals that all the crude extracts are active in a MIC range between 6.2-25 mg/mL, being S. aureus more susceptible to the inhibitory effect of these extracts. On the other hand, due to the photooxidation of brazilin, the evaluation of the antimicrobial potential both in vitro and in silico was carried out for its oxidation product, brazilein, along with the bioprospecting of its spectrum of biological activities using in silico modeling on the PASS web platform. Brazilein only exhibited inhibitory activity against the S. aureus strain with a MIC=12.5 mg/mL. Likewise, in silico modeling indicated 50 possible bacterial targets on which this molecule could have antibacterial effects, which contrasts with the set of biochemical targets identified as possible mechanisms of action through which brazilein could exert antimicrobial effects. © 2023 Laboratorios Mixim S.A. de C.V.. All rights reserved.