ABSTRACT

Microorganisms exist ubiquitously around and inside us. We are bombarded with them from the moment we are born. Many are critical to human survival and some are pathogenic. The rate of infections caused by bacteria that have acquired antibiotic resistance is a staggering proportion. The life-saving drugs, which held a great deal of promises during the 1940s to eradicate all the infectious life-threatening diseases in the world, have ceased to work, because of the increasing emergence of microbial strains invulnerable to them. Many of the previously efficacious antibiotics are no longer usable because of widespread occurrence of multiresistant microbial strains. Essential oils from spices, medicinal plants, and herbs have been shown to possess antimicrobial activities and could serve as a source of antimicrobial agents against some pathogenic bacteria. The essential oil of Melaleuca alternifolia, or tea tree oil, is a widely used naturally occurring antimicrobial which has been recommended in the treatment of many cutaneous conditions. This study of antibacterial activity against selected pathogens was done by Disc diffusion method. Pathogens (Staphylococcus aureus, Streptococcus pyogenes, Pseudomonas aeruginosa and Escherichia coli) were taken for this study. The microorganisms were sub-cultured and identified by morphological and biochemical tests. The sample was diluted using 0.01% DMSO in different concentration and infused into paper discs. A bacterial lawn was created on already solidified Muller Hinton agar plates using an inoculating wire loop. The plates were incubated at 37°C overnight and measured after 24hours of incubation. Tea Tree oil showed 100% inhibition against all the bacteria selected for this study due to the clear zone of inhibition measured. The development of Tea Tree oil would be a great alternative to conventional antibiotics against bacterial infections and many more infectious diseases.