The oxidation of lipids in food products, together with the growth of undesirable microorganisms results in the development of spoilage, off-?avor, rancidity and deterioration; rendering such products unacceptable for human consumption. Since ancient times, aromatic herbs and spices have been added to different types of food to improve their ?avor and organoleptic properties. Also, they have great potential in the emerging nutritious industry, because these materials are often considered as neutraceutical and are used in prevention and curative treatments throughout the world. Thus, many aromatic plants are today considered as the most important sources for the extraction of compounds with strong antioxidant and antimicroial activities. Turmeric ( Curcuma longa L., Zingiberaceae) is extensively used as spice in domestic cooking. In combination with other natural dyes, it is also used as a coloring agent for textiles, pharmaceuticals, confectionary and cosmetics. At present, about 80% of Iran , s counsuming turmerics is provided from the countries India and Pakistan that besides providing Iran , s internal needs, is also exported to different countries. The aim of this research is to compare antioxidant and antimicrobial effects of the resultant extract from imported turmerics to Iran, to be able to make importing and exporting of this valuable plant purposeful. Extraction of essential oils and oleoresins of Indian and Pakistanian rhizomes turmeric was the first step of this study, then extraction yield was calculated. The antioxidant activity of essential oil and oleoresins were evaluated against soya oil by peroxide and thiobarbituric acid (TBA) value, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Hydroxyl Radicals scavenging methods. Their antibacterial effects towards Escherichia coli and Bacillus cereus were also tested by a disc diffusion assay and evaluating minimal inhibitory concentrations of this component by Broth dilution method. In all of chemical and microbial tests, the essential oil and all oleoresins showed moderate to good inhibitory effects. Though, both essential oils and oleoresins were found to be effective, Indian oleoresin of turmeric rhizome was found to be significantly better than other extracts. Although the difference wasn ? t very big. Key word Turmeric, essential oil, oleoresin, Escherichia coli , Bacillus cereus
