Plasmid Borne Resistance in Bacteria to Common Household Spices

Aim: To examine the antimicrobial properties of various spices commonly used in Indian cuisine and to check if the resistance in bacteria is plasmid borne.
Study Design: To demonstrate the antimicrobial properties in various household spices like Cinnamon (Cinnamomum zeylanicum), Clove (Syzygium aromaticum), Black Pepper (Piper nigram) and Turmeric (Curcuma longa) and to examine their effects on the pathogenic bacteria Escherichia coli, Bacillus subtilis, Klebsiella pneumoniae, Pseudomonas aeruginosa and Staphylococcus aureus.
Place and Duration of Study: Department of Microbiology, Osmania University, India during June 2013- January 2014.
Methodology: Antimicrobial assay was performed to determine the antimicrobial activity of these spices. Plasmids were isolated from bacteria showing resistance to these spices to confirm if the resistance to these spices was plasmid borne. The isolated plasmids were used to transform E. coli DH5α which was previously observed to be sensitive to these spices.
Results: On transformation with plasmids isolated from K. pneumoniae and P. aeruginosa, E. coli DH5α cells were observed to gain resistance to all the four spices tested in the original strains of K. pneumoniae and P. aeruginosa.
Conclusion: The resistance to spices seems to be a plasmid borne feature which may be transferred to sensitive bacterial strains.