In vitro antibacterial activity of some plant essential oils.

Seenivasan Prabuseenivasan,Manickkam Jayakumar,Savarimuthu Ignacimuthu

doi:10.1186/1472-6882-6-39

Abstract

Background:To evaluate the antibacterial activity of 21 plant essential oils against six bacterial species.Methods:The selected essential oils were screened against four gram-negative bacteria (Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus vulgaris) and two gram-positive bacteria Bacillus subtilis and Staphylococcus aureus at four different concentrations (1:1, 1:5, 1:10 and 1:20) using disc diffusion method. The MIC of the active essential oils were tested using two fold agar dilution method at concentrations ranging from 0.2 to 25.6 mg/ml.Results:Out of 21 essential oils tested, 19 oils showed antibacterial activity against one or more strains. Cinnamon, clove, geranium, lemon, lime, orange and rosemary oils exhibited significant inhibitory effect. Cinnamon oil showed promising inhibitory activity even at low concentration, whereas aniseed, eucalyptus and camphor oils were least active against the tested bacteria. In general, B. subtilis was the most susceptible. On the other hand, K. pneumoniae exhibited low degree of sensitivity.Conclusion:Majority of the oils showed antibacterial activity against the tested strains. However Cinnamon, clove and lime oils were found to be inhibiting both gram-positive and gram-negative bacteria. Cinnamon oil can be a good source of antibacterial agents.

Highlights

To evaluate the antibacterial activity of 21 plant essential oils against six bacterial species
The anti-bacterial activity of twenty-one selected essential oils against six bacterial species is summarized in Table 2 and 3
The results revealed that the selected essential oils showed antibacterial activity with varying magnitudes

Summary

Introduction

To evaluate the antibacterial activity of 21 plant essential oils against six bacterial species. Down the ages essential oils and other extracts of plants have evoked interest as sources of natural products. They have been screened for their potential uses as alternative remedies for the treatment of many infectious diseases [1]. Medicinal and aromatic plants which are widely used as medicine and constitute a major source of natural organic compounds. Essential oils have been shown to possess antibacterial, antifungal, antiviral insecticidal and antioxidant properties [2,3]. Some oils have been used in cancer treatment [4]. Essential oils are a rich source of biologically active compounds. There has been an increased interest in looking at (page number not for citation purposes)

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Discussion

Conclusion