Antimicrobial activity of spices against Gram positive and Gram negative organisms

Since ancient times, spices are one of the important part of the human diet. In addition, it is used for providing flavor to food and also it possess various preservatives and medicinal values. Spices like turmeric, ginger and chilli exhibit antimicrobial properties. Turmeric is useful for home remedies and is now becoming a great research of interest for its anti-cancerous property. Even in Ayurveda spices are used as main ingredients for preparation of various medicines. This research aimed at studying antimicrobial activity of turmeric, ginger and chilli against Gram positive and Gram negative organisms. Standard laboratory strains of Escherichia coli, Staphylococcus aureus and Bacillus subtilis were selected for this study. Extracts of spices were prepared using different concentrations of DMSO as solvent (50% and 100%). Disk Diffusion Method was employed for comparative study of each selected spice on selected standard strains. The result demonstrated that the extracts of spices with 100% of DMSO showed greater zones of inhibition as compared to 50%. Gram positive bacteria are more sensitive to chilli and turmeric extracts than Gram negative bacteria whereas Gram negative bacteria are more sensitive to ginger extracts than Gram positive. Various studies have shown that gingerol, a naturally occurring phenol found in ginger disrupts the cell wall of bacteria causing cytoplasmic leakage. Spices might have greater potential to be used as an antimicrobial agents. Also, spices other than turmeric, ginger and chilli can be screened for their antimicrobial activities against microbial pathogens