Food Control 18 (2007) 646–649 www.elsevier.com/locate/foodcont 0956-7135/$ - see front matter  2006 Elsevier Ltd. All rights reserved. doi:10.1016/j.foodcont.2006.03.002 Antimicrobial activities of Iranian sumac and avishan-e shirazi (Zataria multiXora) against some food-borne bacteria Mohammad Reza Fazeli a,¤ , Gholamreza Amin b , Mohammad Mahdi Ahmadian Attari a , Hesam Ashtiani a , Hossein Jamalifar a , Nasrin Samadi a a Department of Drug and Food Control, Pharmaceutical Sciences Research Center and Medicinal Plant Research Center, School of Pharmacy, Tehran University of Medical Sciences, Enghelab Street, P.O. Box 14155/6451, Tehran, Iran b Department of Pharmacognosy and Medicinal Plant Research Center, School of Pharmacy, Tehran University of Medical Sciences, Enghelab Street, P.O. Box 14155/6451, Tehran, Iran Received 19 December 2005; received in revised form 27 February 2006; accepted 6 March 2006 Abstract Food poisoning originating from contaminated foods by both Gram-positive and Gram-negative bacteria causes concern to society and to the industry. Spices have been used safely since ancient times as food Xavoring agents and also as herbal medicines and are now mainly considered “generally regarded as safe” (GRAS). Antimicrobial eVects of two spices used in Iranian traditional medicine were investigated against some pathogenic food-borne bacteria. Hydroalcoholic extracts of Rhus coriaria L. (sumac) and Zataria multiXora Boiss. (avishan-e shirazi or zaatar) obtained from Tehran botanicals market were prepared by cool percolation method using 80% (v/v) aqueous alcohol. Antimicrobial activities of the extracts were tested against several Gram-positive and Gram-negative bacteria including Staphylococcus aureus, Bacillus cereus, Escherichia coli, Salmonella typhi, Proteus vulgaris, and Shigella Xexneri. All the extracts were pri- marily screened for their possible antimicrobial eVects using disc and well diVusion methods. Both R. coriaria L. and Z. multiXora Boiss. showed considerable antibacterial eVects. The potential antibacterial activities of the two herbal extracts were further investigated at con- centrations of 0.05%, 0.1%, 0.2%, 0.4%, 0.8% and 1.6% (w/v) and minimum inhibitory concentration (MICs) as well as minimum bacterici- dal concentrations (MBCs) of the extracts were elucidated. Sumac showed better activity against the tested bacteria compared to avishan- e shirazi inhibiting Bacillus cereus and Staphylococcus aureus at concentrations of 0.05% and 0.1%, respectively while Gram-negative bac- teria were aVected by higher concentrations of sumac ranging 0.1–2%. The MICs of avishan-e shirazi against the tested bacteria ranged from 0.4% to 0.8%. Salmonella typhi was found to be the most resistant showing the MICs of 0.2% and 0.8% with sumac and avishan-e shirazi, respectively. Both popular Iranian spices which are traditionally used as astringent agents have promising inhibitory eVects on food-borne bacteria and could be considered as natural food preservatives.  2006 Elsevier Ltd. All rights reserved. Keywords: Iranian sumac; Avishan-e shirazi; Zaatar; Food-borne bacteria; Natural preservative 1. Introduction Food-borne diseases are still a major concern in some developing countries. Due to the world awareness on chemical preservatives the food industry is now reXected by the consumer opinions for safer additives and thus focusing on natural GRAS preservatives (Dillon & Board, 1994). Spices are herbal products which have been safely used by people around the world to impart desirable Xavors and aromas to the local foods. It looks that there has been a natural selection for spices as these products are mainly originated from plants grown in the tropical regions with wide distribution of food-borne bacteria. Sev- eral of these spices and their essential oil extracts have * Corresponding author. Tel.: +98 912 1484810; fax: +98 21 6959060. E-mail addresses: fazelimo@sina.tums.ac.ir, mofazeli@yahoo.com (M.R. Fazeli).