Comparative Study of Antibacterial Activity of Different Essential Oils against Different Bacteria

Abstract

The problem caused by drug resistant pathogenic bacteria has become a common phenomenon from the last few decades. People infected with many bacteria which was once easily curable by the administration of proper antibiotics, have become difficult to eradicate due to their acquisition of antibiotic resistant trait. As a result people are dying from lack of proper medication which will be able to kill such pathogens. In search of such potent therapeutics, natural resources are targeted and essential oil is such a natural resource which can actively inhibit different pathogenic bacteria. Current study aimed in to determine the potency of tea tree essential oil, sweet orange essential oil and ylangylang essential oil against antibiotic resistant bacteria. The efficacy of the essential oils was determined against Staphylococcus aureus, Pseudomonas luteola, Pseudomonas aeruginosa, Klebsiella pneumonia, Bacillus subtilis and Escherichia coli and was compared by using both micro dilution and agar well diffusion method. The highest average inhibition rate was found for tea tree essential oil (93.67%) followed by ylang-ylang (81.33%) and sweet orange essential oil (74.16%) after twenty four hours. Tea tree oil was 100% effective against all bacteria used in this experiment except Bacillus subtilis (62%). Highest percentage inhibition for ylang-ylang was against Klebsiella pneumoniae (100%). Sweet orange essential exhibited 100% inhibition for Klebsiella pneumoniae, Pseudomonas luteola and Escherichia coli. Tea tree oil has the highest ability to inhibit all of the six selected bacteria which are already resistant to antibiotics. It has been observed that multi drug resistant isolates (Escherichia coli-resistant to 4 th generation cephalosporin) is surprisingly inhibited by all of these essential oils. The antibacterial properties of these oils can be aimed to produce new therapeutics to combat the resistant bacteria.