Journal of Food Safety 25 (2005) 130–145. All Rights Reserved. 130 © Copyright 2005, Blackwell Publishing ANTIOXIDATIVE AND ANTIBACTERIAL POTENTIALS OF ESSENTIAL OILS AND EXTRACTS ISOLATED FROM VARIOUS SPICE MATERIALS* G. SINGH 1,3 , P. MARIMUTHU 1 , H.S. MURALI 2 and A.S. BAWA 2 1 Chemistry Department DDU Gorakhpur University Gorakhpur 273 009 India 2 Defence Food Research Laboratory Mysore 570 011 India Accepted for Publication December 10, 2004 ABSTRACT The antioxidant and antibacterial potentials of essential oils and acetone extracts of black pepper, cumin, black cumin and mace were carried out by different techniques. The antioxidative capacity of the essential oils and ace- tone extracts were evaluated against mustard oil by measuring peroxide and thibarbituric acid values at fixed intervals. In addition, their antioxidant potential was evaluated by 2, 2¢-diphenyl-1-picrylhydracyl radical and con- jugated diene assays. Their reducing power was determined with standards, which proved the strong antioxidant capacity of essential oils and extracts. The antioxidant activity of essential oils and extracts exerted by all the anti- oxidant assays can be compared with synthetic antioxidants such as butylated hydroxyanisole and butylated hydroxytoluene. The antibacterial activity was studied by disk diffusion and poison food methods. Black cumin essential oil showed complete zone of inhibition (P < 0.05) against tested bacterial strains of Staphylococcus aureus, Bacillus cereus and Bacillus subtilis at 2 and 6 mL level by disk diffusion method. Black cumin and black pepper extracts showed complete reduction of colonies against tested bacterial strains of S. aureus, B. cereus and B. subtilis at 5 and 10 mL level by poison food method. Poison food method exhibited good results for the tested essential oils and extracts. Essential oils of black pepper, cumin, black cumin and mace may be used to stabilize mustard oil after screening. Blackwell Science, LtdOxford, UKJFSJournal of Food Safety0149-6085Copyright 2005 by Food & Nutrition Press, Inc., Trumbull, Connecticut.2005252130145Original Article ANTIOXIDANT AND ANTIBACTERIAL POTENTIAL G. SINGH ET AL. 3 Author for correspondence. TEL: 91-551-2200745 (R) 2202856 (O); FAX: 91-551-2340459; EMAIL: gsingh4us@yahoo.com * Part 48.