Lippia origanoides supercritical fluid extract and its major constituent pinocembrin diminish ultraviolet radiation-induced DNA damage and modulate cell division in Escherichia coli

Abstract

The objective of this work was to evaluate DNA protective properties against UVR-induced genotoxicity of an L. origanoides extract obtained by CO2-supercritical fluid extraction and its major constituent, pinocembrin. L. origanoides extract composition was determined by gas chromatography-mass spectrometry (GC-MS) and its antigenotoxic effect using the SOS chromotest. Fluorescence microscopy analysis was also used in cell treatments in order to determine interferences with cell division and different nucleoid shapes categories were measured. The principal constituents of the plant extract were pinocembrin (54.9%), trans-β- caryophyllene (10.9%), carvacrol (6.3%), p-cimene (6.2%), thymol (4.6%), and 1,8-cineole (3.5%). L. origanoides extract protected bacterial cells against UVR-induced genotoxicity at doses between 0.016 and 1 mg/mL; this effect was related to its major constituent pinocembrin. Fluorescence microscopy analysis showed that pinocembrin modulated the cell division and nucleoid shape in E. coli cells. The results were discussed in relation to the DNA protective potential of the L. origanoides species.