EFFECT OF g-IRRADIATION ON THE CHEMICAL COMPOSITION AND ANTIOXIDANT PROPERTIES OF CUMIN EXTRACTS F. FATEMI 1,5 , A. DADKHAH 2 , M.B. REZAEI 3 and S. DINI 4 1 Nuclear Science Research School, Nuclear Science and Technology Research Institute, Tehran 1439951113, Iran 2 Faculty of Science, Qom Branch, Islamic Azad University, Qom, Iran 3 Department of Medicinal Plants, Institute for Research in Forests and Rangelands, Tehran, Iran 4 Department of Horticulture, Faculty of Agriculture and Natural Resources, Islamic Azad University, Karaj Branch, Karaj, Iran 5 Corresponding author. TEL: 021-88221076; FAX: 021-88221074; EMAIL: ffatemi@aeoi.org.ir Accepted for Publication October 10, 2011 doi:10.1111/j.1745-4514.2011.00641.x ABSTRACT The effect of g-irradiation on the composition of cumin extracts and also their anti- oxidant properties were considered. The seeds before and after irradiation (10 and 25 kGy) were subjected to Clevenger extraction to obtain essential oils, and the constituents were identified by gas chromatography–mass spectrometry (GC/MS) analysis. In parallel, the hydroalcoholic extract was used for measuring flavonoid content, free-radical scavenging (2,2-diphenylpicrylhydrazyl assay) and antioxidant properties (b-carotene bleaching test). The results of 10 fractions separated by GC/MS indicated that the total percentage was not affected by g-irradiation. g-irradiation of cumin seeds also resulted in a nonsignificant change in flavonoid content of the hydroalcoholic extracts. The antioxidant activities of both extract showed potent activities which were not further altered in irradiated samples. These data suggest that g-irradiation to cumin seeds is effective for maintaining the com- position and antioxidant properties of the seeds. PRACTICAL APPLICATIONS Cumin is a traditional plant, originally cultivated in Iran and the Mediterranean region. Cumin is one of the most popular spices in the world widely used as a food flavoring agent. It is also used in Iranian traditional medicine for treatment of differ- ent diseases. Considering the contaminations of the seeds by microorganisms, their decontamination by g-irradiation seems to be useful. In this study, the compositions and antioxidant activities of the extracts derived from g-irradiated cumin seeds in comparison with nonirradiated ones will be achieved. INTRODUCTION Cumin (Cuminum cyminum L., Apiaceae [Umbelliferae]) is a traditional plant, originally cultivated in Iran and the Medi- terranean region (Grieve 2005; Tbaileh et al. 2007). Cumin has been in use since ancient times. Seeds excavated at the Syrian site Tell ed-Der have been dated to the second millen- nium BC. They have also been reported from several New Kingdom levels of ancient Egyptian archaeological sites (Zohary and Hopf 2000). The seed is widely used as a food fla- voring agent in cheeses, pickles, sausages, soups and bean dishes, and has several important medicinal uses. It is benefi- cial to the digestive system and acts as a stimulant to the sexual organs, used in coughs as painkiller and to treat rotten teeth (Zargari 1994; Platel and Srinivasan 2004; Agarwal et al. 2010). It is also used in the treatment of flatulence and bloat- ing, reducing intestinal gas, and in treatment of insomnia, colds, fevers, diarrhea, toothache and epilepsy and to improve milk production (Zargari 1994; Platel and Srinivasan 2004; Srinivasan 2005; Tbaileh et al. 2007; Agarwal et al. 2010). All these biological activities have been found either in aqueous extract, oil or in organic compounds isolated from cumin. The seeds on distillation yield a colorless or yellow vola- tile oil having an unpleasant characteristic odor, spicy and Journal of Food Biochemistry ISSN 1745-4514 1 Journal of Food Biochemistry •• (2012) ••–•• © 2012 Wiley Periodicals, Inc.