Int.J.Curr.Microbiol.App.Sci (2014) 3(8) 778-792 778 Original Research Article Natural conjugated and trans fatty acids in seed oils and phytochemicals in seed extracts issued from three Tunisian pomegranate (Punica granatum. L) cultivars Manel Mekni*, Madiha Dhibi, Wafa Kharroubi, Rabeb B. Hmida, Imed Cheraif, and Mohamed Hammami Laboratory of 'Nutrition Functional Foods & Health Disease , Faculty of Medicine, University of Monastir, 5019, Tunisia *Corresponding author ABSTRACT Introduction Pomegranate (Punica granatum L.) is one of the oldest edible fruits widely spread in Mediterranean countries, Iran, India and to some extent in the U.S. (California), China, Japan and Russia (Fadavi et al., 2006). In Tunisia, the cultivation of pomegranate has taken a great development in recent years. The pomegranate is cultivated in all regions with a concentration in the southern oases (Gabes) and the northwest region (Testour). Other production centers are located in the coastal stations (Mars and Gaaliche, 1993). Pomegranate seed as a byproduct of pomegranate processing is about 20% (w/w) of the whole fruit depending on cultivar (Tehranifar et al., 2010). Recently, it has been shown that pomegranate seed could potentially be a good source of nutrients and antioxidants in association with the presence of bioactive compounds, particularly polyphenols. Recent studies showed significant levels of phenolic content in pomegranate seeds (Elfalleh et al., 2011). Moreover, the lipid composition of pomegranate seeds is attracting more attention (Fadavi et al., 2006). Consumers ISSN: 2319-7706 Volume 3 Number 8 (2014) pp. 778-792 http://www.ijcmas.com Keywords Pomegranate seed oil; conjugated fatty acids; trans fatty acids; phytochemicals Fatty acid profiles of pomegranate seed oils (PSOs), phytochemicals and antioxidant activities of pomegranate seed extracts (PSE) and pomegranate seed residue extracts (PSRE) of three Tunisian (Punica granatum. L) cultivars were investigated. PSOs lipid characterization showed 32 fatty acids (FA). trans MUFAs represent more than 50% of total MUFAs and exceptionally characterised by the presence of elaidic acid C18:1 n9 (trans) that significantly differed among the studied cultivars (p<0.05). However, PUFAs that seemed most important (83.77%) were mainly characterised by the presence of conjugated fatty acids (CFAs) including conjugated linoleic acids (CLAs) and conjugated linolenic acids (CLnAs), essentially, punicic acid that was the major fatty acid in PSOs ranging from 35.27 to 38.64%. The highest total phenolic content (TPC) was determined as 1.17 mg GAE /g DW of PSE in Tounsi cultivar. Acceptable antioxidant activity of PSE and PSRE were found in Tounsi cultivar with 38.57 and 21.51 % respectively.