The potentials of henna (Lawsonia inamis L.) leaves extracts as counter stain in gram staining reaction

Abstract

The potentials of aqueous and ethanol extract solutions of the henna plant (Lawsonia inamis L.) leaves adopted as alternative counter stain in Gram staining reactions were studied. Different extracts were formulated into various staining solutions of different concentrations. The solutions
were modified with hydrogen peroxide, ferric chloride, potassium alum and potassium permanganate. These staining solutions were used to stain bacterial isolates of Lactobacillus spp and Escherichia coli strains. The experimental henna plant extracts solutions were used with usual
counter stains (neutral red, safranin and dilute carbol fuchsin) as positive controls. The result obtained showed that aqueous extracts (cold and hot) oxidized with potassium permanganate with neutral pH gives a better staining reaction. While the ethanol extract after oxidized with potassium
permanganate had no staining reaction. The result obtained therefore implied that the aqueous henna leaves extracts (cold or hot) when oxidized with potassium permanganate can be a substitute to the usual counter stains used in Gram staining reactions.

Keywords: Aqueous Extract, Dyes, Henna, Counter-Staining