Preliminary Investigation on the in vitro Antibacterial Activity of Ethanolic Extract & Essential Oil of Aloe vera and Opuntia dillenii on Human Bacterial Pathogens

Abstract

Opuntia dillenii and Aloe vera are used as medicinal plants. Opuntia dillenii belongs to Cactaceae and used for treatment of cough and bronchial troubles. Aloe vera belongs to Aloaceae and it is well established for its different medicinal uses ranging from treatment of skin burns to anti metastatic and antimicrobial activity. The aim of the present study was to evaluate the antimicrobial activity of ethanol extracts and essential oils of Aloe vera and Opuntia dillenii against selected human pathogens viz., Staphylococcus aureus, Streptococcus pneumoniae, Bacillus spp., Klebsiella pneumoniae, Salmonella typhi and Shigella dysenteriae by disk diffusion method and Triphenyl Tetrazolium Chloride (TTC) staining. The ethanol extract of Opuntia dillenni and Aloe vera showed good antibacterial activity against all the pathogens tested. Lower Minimum Inhibitory Concentration (MIC) values were obtained for ethanol extracts of both the medicinal plants against the bacterial pathogens except Shigella dysenteriae which was not inhibited at lower concentrations. The essential oils of Opuntia dillenni and Aloe vera also exhibited excellent antimicrobial activity against bacterial pathogens where Shigella dysenteriae was inhibited only at higher concentrations.