Chemistry and Physics of Lipids 165 (2012) 608–614 Contents lists available at SciVerse ScienceDirect Chemistry and Physics of Lipids jou rn al hom epa ge : www.elsevier.com/locate/chemphyslip Triacylglycerols composition, oxidation and oxidation compounds in camellia oil using liquid chromatography–mass spectrometry Alam Zeb ∗ Department of Biotechnology, University of Malakand, Chakdara, Pakistan a r t i c l e i n f o Article history: Received 31 October 2011 Received in revised form 6 March 2012 Accepted 12 March 2012 Available online 24 March 2012 Keywords: HPLC–ESI-MS Camellia oil Auto-oxidation Oxidation products Oxidized triacylglycerols Free radical reaction Lipid oxidation a b s t r a c t Camellia seed oil is one of most important edible oil, rich in oleic acid and contains many natural antiox- idants with various biological activities. During preparation of foods or storage camellia oil oxidizes by the auto-oxidation and produce oxidized compounds. Traditional analytical techniques like FFA, POV are used for the determination of oxidation and adulteration of oils and fats. These methods were rarely able to detect the oxidized compounds produced and extent of oxidation. This paper presents the uses of liquid chromatography coupled to electrospray ionization mass spectrometry (HPLC–ESI-MS) for the analysis of triacylglycerols (TAGs) composition and evaluation of auto-oxidation and oxidation products of camellia seed oil. The camellia oil was auto-oxidized for 12 months at room temperature. The TAGs were identified from their characteristics fragmentations such as protonated molecular ion, ammonium and sodium adducts, diacylglycerols, epoxy-diacylglycerols fragments and mono-acylglycerol fragments in ESI-MS mass spectra. HPLC–ESI-MS data revealed the separation and identification of 15 TAGs. The major TAGs separated and identified in camellia seed oil were POO, OOO, OLO, PLO/POL, OLL, SOO, ALO and OLLn. The auto-oxidation studies revealed a total loss of LnLLn, LnOLn, LLLn and OLLn amounting about 13.5% total oxidation. The auto-oxidation products were epoxy hydroperoxides, epoxy epidioxides, and mono-epoxides. It was observed that these were characteristic compounds produced in high oleic oils. © 2012 Elsevier Ireland Ltd. All rights reserved. 1. Introduction Triacylglycerols are the principal components of plant oils. The properties of the oils are dependent on the fatty acids composition. The presence of polyunsaturated fatty acids increases the poten- tial beneficial properties of the oils. However, the polyunsaturated oils are more prone to oxidation of different kinds (Kamal-Eldin et al., 2003). Triacylglycerols are one of the prime determinants in the study of oxidation of oils. During the oxidation (auto-, thermal, photo) triacylglycerols are oxidized to hydroperoxides. These hydroperoxides are highly reactive species (Hamilton et al., 1997). Hydroperoxides are then further oxidized or degraded to a wide variety of secondary oxidation products. These oxidized compounds are usually absorbed by the foods and consequently enters human body. It was established that oxidized fats and oils are toxic (Frankel et al., 1984) and are major contributing factor in a Abbreviations: ESI-MS, electrospray ionization mass spectrometry; TIC, total ion chromatogram; ACS, American Chemical Society; BHT, butylated hydroxyl toluene; A, arachidic; G, gadoic; L, linoleic; Ln, linolenic; P, palmitic; O, oleic; S, stearic; [LOep] + , epoxide of LO. ∗ Tel.: +92 945 763442x3019. E-mail address: Alamzeb01@yahoo.com variety of human diseases or conditions such as aging, atheroscle- rosis, arthritis, inflammatory bowel disease, neurodegenerative disease, and some eye diseases (Halliwell, 1994). The oxidized fats were found significance to human health since some of these oxi- dation products may be carcinogenic (Yang et al., 1998). Jurek et al. (2005) showed that dietary lipid hydroperoxides are a key factor in colon carcinogenesis. Recently Rohr-Udilova et al. (2008) observed that hydroperoxides from the dietary oxidized oils enhances the growth of hepato-carcinoma. The analysis of oxidation and oxida- tion compounds in oils or fats is thus an important point of concern in food industries to health sectors. Camellia oleifera is a member of the Theaceae family, widely known as tea seed plant. It is native to China, and South-east Asia (Qizhi et al., 2008). It is also grown as an ornamental plant in West- ern countries. It has been used in Chinese traditional medicine and in cosmetics (Chaicharoenpong and Petsom, 2011). Camellia oil is rich in oleic acid (C18:1) and contain many natural antioxidants with various biological activities (Shyu et al., 1990). The camellia oil has been observed to suppress cholesterol content in the body and provide resistance to oxidative stress (Fu and Zhou, 2003). Camel- lia oil contains 75–80% oleic acid (Chaicharoenpong and Petsom, 2011), similar to olive oil, while the saturated fats are present in low amounts. Because of the high oleic contents, camellia oil pro- vides health-promoting effects include lowering blood pressure, 0009-3084/$ – see front matter © 2012 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.chemphyslip.2012.03.004