Abstract

The present study highlights the antimicrobial properties of the medicinal plant Hibiscus sabdariffa (H. sabdariffa) essential oils and their effect of chemical constituents against biofilm-producing Gram negative bacteria. Initially, the complete chemical composition of H. sabdariffa essential oils profiles from crude extract were screened by LC-MS analysis. Screening of anti-biofilm properties from essential oil were purified and fractionated separately using preparative HPLC. Subsequently, the phytochemical analysis results suggested that the H. sabdariffa essential oils possess enormous phenolic and flavonoid contents, which may contribute in the bioefficiency. Further, the quantification of biofilm inhibition was suggested, purified HPLC fraction 2 inhibited the virulence behavior in biofilm-producing E. coli and P. mirabilis without affecting bacterial growth at concentration dependent mode. Metabolic activity inactivation and complete biofilm growth cell arrest due to the purified HPLC fraction 2 was quantitatively showed 96 % and 94 % at increased concentration using XTT assay. Furthermore, the architectural damage and dissemble of intracellular membranes of the biofilm cells at biofilm inhibition concentration were clearly observed by confocal laser scanning electron microscope. Destruction of the extracellular layer and surface morphology damages to the transfer of charged molecules from H. sabdariffa essential oils into bacterial surface was observed by scanning electron microscope. Finally, the result was concluded that the purified HPLC of H. sabdariffa essential oils have excellent anti-biofilm properties against biofilm producing bacteria, and it can be alternative drug discovery choice in the future to eradicate various infectious diseases.