Comparative Antimicrobial Activity of Aloe Vera Gel on Microorganisms of Public Health Significance

The comparative antimicrobial activity of different preparations of Aloe vera gel (fresh gel, preserved gel, cooling gel and acne cream) was studied against a number of microorganisms of public health significance by disc diffusion method. It was found that the fresh gel and preserved gel exhibited maximum zones of inhibition against Bacillus subtilis (24.7 & 34.5 respectively), where as cooling gel and acne cream against Staphylococcus aureus (30.3 & 26.3mm respectively) at 37C and similarly, minimum inhibition zones by all four preparations of Aloe vera gel were shown against Aspergillus ficuum (9.5, 15.5, 10.5 and 9.5mm respectively) after a period of 48h of incubation at 25C. However, its various preparations exhibited variable toxicity against one or more tested strains of Aspergillus, Fusarium, Penicillium, Candida, Escherichia, Salmonella, Proteus, Staphylococcus and Bacillus. It was found that Salmonella typhimurium and Bacillus cereus showed a minimum 1.0% decrease from 48 to 96h in zones of inhibition whereas Escherichia coli exhibited a maximum decrease of 29.6% against acne cream after a period of 96h of incubation. It was concluded that the cumulative mean value of Aspergillus niger, Aspergillus ficuum, Fusarium. solani, Penicillium digitatum, Candida utilus, Escherichia coli, Salmonella typhimurium, Proteus vulgaris, Staphylococcus aureus, Bacillus subtilis and Bacillus cereus resulted in 14.25(I), 11.25(I), 15.66(S), 13.55(I), 20.28(S), 19.45(S), 13.37(I), 11.25(I), 26.22(S), 27.30(S) and 25.95(S) against fresh gel, preserved gel, cooling gel and acne cream respectively. The results of this study tend to give credence to the popular use of different preparations of Aloe vera gel as effective as modern medicine to combat pathogenic microorganisms.