Antimicrobial Effects Of Aloe Vera On Some Human Pathogens

ABSTRACT

The crude extract of Aloe Vera gel was investigated with the aim of determining the antimicrobial activity, the best solvent to be used for extraction and the organism that is most susceptible to the crude Aloe vera gel extract. Ethanol, Methanol and Aqueous (hot) were used as solvents for extraction. Although aqueous extract had the highest yield (19.0g) after extraction as compared to ethanol (18.40g) and methanol (18.20g), ethanol was still regarded as the best solvent for extraction. The susceptibility of Escherichia coli, Staphylococcus aureus and Candida albicans to the crude extracts of Aloe vera gel was determined by agar well diffusion method. Gentamycin was used as positive control while dimethylsulphoxide (DMSO) was used as a negative control. The ethanol extract inhibited the growth of Escherichia coli, Staphylococcus aureus and Candida albicans with zones of inhibition of 6, 5, and 4mm respectively while aqueous extract had zones of inhibition of 6, 4 and 3mm respectively. The methanol extract inhibited the growth of Escherichia coli (3mm) only. The ethanol extract gave a better minimum inhibitory concentration (MIC) (0.125, 0.125 and 0.50mg/ml) than aqueous extract (0.25, 0.25 and 0.5mg/ml) and methanol extract (0.50, 0.00 and 0.OOmg/ml) on Escherichia coli, Staphylococcus aureus and Candida albicans respectively. The study revealed that ethanol and aqueous extracts of aloe vera gel was susceptible to the three pathogens and also lend more weight to general acceptability of these crude extracts for therapeutic purposes.