Bulletin UASVM Agriculture, 67(2)/2010 Print ISSN 1843-5246; Electronic ISSN 1843-5386 Lipid Composition of the Hazelnut (Corylus Pontica C. Koch.) Cv. Ata Baba Grown in Bulgaria Svetlana MOMCHILOVA 1) , Magdalena NIKOLOVA 2) , Ivalina KUZMANOVA 1) , Diana NEDELCHEVA 1) , Ilko MAREKOV 1) , Svetlana PANAYOTOVA 1) 1) Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., bl. 9, 1113 Sofia, Bulgaria; svetlana@orgchm.bas.bg 2) Agricultural Experiment Station, Agricultural Academy, Minjorska Str. 1, 6600 Kardzhali, Bulgaria Abstract. Hazelnut (Corylus Pontica C. Koch.) cultivar Ata Baba grown in Bulgaria (harvest year 2009) has been investigated about neutral lipid classes, their fatty acid composition and the triacylglycerol species. Fat content of the oil (66.2%) was determined gravimetrically after extraction of dry kernels in Soxhlet apparatus (6 h with hexane). On the other hand, fresh kernels were treated firstly with iso-propanol and then extracted by chloroform-methanol (2:1) mixture (Christie, 1993) in order to obtain hazelnut oil for analyses of lipids. The neutral lipid classes were separated by thin layer chromatography (silica gel G plates, developed with hexane-acetone, 10:1 v/v), identified towards a standard mixture, isolated and weighed. It was established that the hazelnut cultivar Ata Baba contained polar lipids (0.6%), diacylglycerols (0.9%), sterols (0.9%), unidentified lipid zone X (0.8%), triacylglycerols (96.1%) and sterol esters (0.7%). Each of these classes (excepting free sterols) was transmethylated according to Christie (2003) and the methyl esters were analysed by gas chromatography (see Table 1). Tab. 1 Fatty acid composition (w.%) of individual lipid classes in hazelnut cv. Ata Baba 14:0 16:0 16:1 18:0 9- 18:1 11- 18:1 18:2 18:3 20:0 20:1 20:2 22:0 StE 2.2 14.8 0.3 4.8 43.9 1.4 29.5 1.5 0.5 0.2 tr. 1.0 TAG 0.1 7.4 0.3 2.0 71.6 1.4 16.8 0.1 0.1 0.1 tr. tr. X 0.9 8.8 0.3 2.7 52.9 1.1 30.3 2.1 0.2 0.1 tr. 0.4 DAG 0.4 9.4 0.2 1.9 50.0 1.7 35.7 0.2 0.1 0.1 0.1 0.2 PL 2.8 22.0 0.6 7.8 41.4 1.3 20.1 0.3 0.9 tr. 0.8 2.1 PL-polar lipids, DAG-diacylglycerols, X-unidentified lipid zone, TAG-triacylglycerols, StE-sterol esters; tr.- traces (<0.05%) The triacylglycerols were determined by reversed phase HPLC with ELS detector. Identification was towards standards of individual triacylglycerols. Eleven TAG species were measured, namely LLL, LLO, LLP, LOO, LOP, OOO, LOS, OOP, LPS, OOS and OPS (L-linoleic, 18:2; O-oleic, 18:1; P-palmitic, 16:0; S-stearic, 18:0 acyl residues). Keywords: hazelnuts, lipid classes, fatty acid composition, triacylglycerols, chromatography. Acknowledgments. This study has been financed by the National Science Fund of Bulgaria, project DO02-239. REFERENCES 1. Christie, W. W. (1993). Preparation of Lipid Extracts from Tissues, in: Advances in Lipid Methodology-Two, The Oily Press, Dundee, Scotland, 195-213. 2. Christie, W. W. (2003). Preparation of Derivatives of Fatty Acids, in: Lipid Analysis, The Oily Press, Bridgwater, England, 205-224.