Studies on Antimicrobial and Phytochemical properties of Indigenous Indian Plants against Common Food Spoilage Microorganisms

The success of food quality control lies in the continuous search for new antimicrobial agents to counter the challenge posed by resistant microorganisms. Methanol, ethanol, and hot-water extracts of five medicinal spices [Allium sativum (garlic), Syzygium aromaticum (clove), Trachyspermum ammi (ajwain), Cuminum cyminum (cumin) & Trigonella foenum graecum (Methi)] traditionally used in India house-hold as flavor stimulants were investigated for in vitro antimicrobial activity against food borne pathogens namely Escherichia coli, Staphylococcus aureus, Bacillus subtilus, Klebsiella pneumoniae, Enterobacter spp., Saccharomyces cerevisiae, Rhodotorula spp., Aspergillus niger, Penicillium notatum, by disc diffusion method. Methanol-ethanol extracts of Syzygium aromaticum and Trachyspermum ammi showed the highest antimicrobial activity (25-48mm & 25-47mm respectively) against all the tested bacterial and fungal isolates, while Trigonella foenum graecum extracts revealed the least activity (0.0-8mm). Minimum inhibitory concentration (MIC) assay were determine for these four extracts against all the tested organisms. Methanol- clove revealed the highest antimicrobial activity at a minimum concentration of (10-20µg/ml) against all the tested microorganisms, followed by methanol-ajwain at concentration of (20µg/ml) against all the experimental organisms except Klebsiella pneumonia. The phytochemical analysis carried out revealed the presences of Tannins, Saponins, Flavornoids, Terponoids, Glycosides, Alkaloids, Phenolics which are responsible for the antimicrobial activity. The results of these experiments, provides justification for the use of spices in preservation of food stuffs