In-vitro Antimicrobial Study of Non/irradiated Ylang-ylang Essential Oil Against Multi Drug Resistant Pathogens with Reference to Microscopic Morphological Alterations

Abstract

Essential oils have proven to possess great potential in the field of biomedicine due to their ability to effectively eradicate a diverse range of pathogenic microbes. In this study, the antimicrobial activity of ylang-ylang essential oil (YY-EO) was screened against twelve multidrug-resistant pathogens. The YY-EO was effective up to 536 μg/ml, with the highest inhibition zone in case of S. aureus MMCC21 and Escherichia coli MMCC24. The least effect on both Bacillus cereus MMCC11 and Klebsiella pneumonia MMCC16. The major components of the essential oil were identified using GC–MS analysis. Different gamma irradiation doses against the YY-EO were evaluated as a tool of natural decontamination. Moreover, the antimicrobial assay after irradiation proved no significant changes regarding the antimicrobial activity before and after irradiation of EO at the applied dose. The minimum inhibitory concentration (MIC) for the EO against the tested pathogens was detected. The possible morphological changes in some of the bacterial and yeast cells at the recognized MIC and 2MIC were detected using the scanning electron microscope (SEM). Results revealed a notable change in terms of both the microbial cell population and the morphology of the tested bacterial and yeast cells. The cytotoxicity of ylang-ylang EO was evaluated against normal skin tissue culture and showed a potential cytotoxic effect at concentrated doses. These results refer to the importance of YY-EO as a natural antimicrobial agent and the possible application of YY-EO as a surface decontaminant, but they also draw attention to the importance of the EO concentration used in different applications to avoid possible toxic effects.