Original article Canarium zeylanicum seed oil: an edible oil with beneficial qualities Kapila N. Seneviratne* & Roshan T. Kotuwegedara Department of Chemistry, University of Kelaniya, Kelaniya, Sri Lanka (Received 7 July 2008; Accepted in revised form 12 November 2008) Summary The quality parameters, fatty acid composition, phenolic compounds and antioxidant properties of the seed oil of Canarium zeylanicum were determined. The results indicate that the seed oil of Canarium zeylanicum is an excellent source of essential fatty acids which contains C18:2 (49.35 ± 0.35%) and C18:3 (19.09 ± 0.01%). The total phenol contents of the seed oil and the seed hull of Canarium zeylanicum were 66 ± 6 and 2014 ± 14 mg kg )1 respectively. The identified phenolic acids in the methanolic extracts of seed oil include 3,4-dihydroxybenzoic acid, p-hydroxybenzoic acid, vanillic acid and ellagic acid. Diphenyl-2- picrylhydrasyl radical scavenging activity, inhibition of deoxyribose degradation and the reducing power of the methanolic extracts of seed oil and seed hull of Canarium zeylanicum are comparable with those of butylated hydroxytoluene solutions. Keywords Antioxidant properties, Canarium zeylanicum, essential fatty acids, phenolic antioxidants. Introduction Several studies have shown that many herbs and plant seed oils contain essential fatty acids and antioxidants that are important in the regular diet. Because of the nutritional, industrial and pharmaceutical applications, the search of new sources of seed oils has become an important area of research in recent times. It is even more important to search for plant-based oils from the seeds that are wasted otherwise because of the lack of chemical and nutritional information. The fatty acid composition of seed oils is an important nutritional factor while the phenolic composition and the anti- oxidant activity are both nutritionally and industrially important. Essential fatty acids are polyunsaturated fatty acids that are not synthesised in the human body from other fatty acids. Plant oils containing the two essential fatty acids, linoleic acid (C18:2) and a-linolenic acid (C18:3) are nutritionally important. The antioxidant properties and the related health benefits of the phenolic substances present in olive oil have been highlighted. Phenolic compounds in virgin olive oil are responsible for several organoleptic charac- teristics (Gutie´ rrez et al., 1989), oxidative stability (Montedoro et al., 1993), and antioxidant properties (Baldioli et al., 1996). Even though olive oil is the major oil that has been subjected to detailed studies on nutri- tional and antioxidant properties (Visioli & Galli, 1998), there is growing interest currently in the scientific com- munity about the beneficial health properties of other edible oils (Beardsell et al., 2002). In addition to com- monly used edible oils, there are traditionally used Sri Lankan seed oils whose consumption has been completely replaced by common edible oils available in the market. Canarium zeylanicum is a large branched tree growing up to 25–30 m high. The plant belonging to the family Burseraceae is endemic to Sri Lanka and it is found in the wet region. The seeds are large, oblong and edible. Flowers and fruits of this plant can be seen in April– September (Wadhwa, 1999). The seed oil of Canarium zeylanicum is edible and this oil has been traditionally used by Sri Lankans as a source of food and for other medicinal purposes. However, such uses are currently limited to rural community and even in the rural community; the current usage of this oil is limited to traditional medicinal purposes. Over 95% of the seeds produced by these plants are not used for any purpose. In the present study, quality parameters, fatty acid composition, phenolic composition and the antioxidant properties of Canarium zeylanicum seed oil (CZSO) was obtained as first detailed chemical information about this seed oil. Such chemical information is important in the evaluation of the potential of CZSO as a supplement for essential fatty acids and as an ingredient for herbal- based beauty care products. The total phenol contents and the antioxidant properties of the phenolic extracts of the seed hull of Canarium zeylanicum were also investigated in order to evaluate the potential of seed hull as a source of phenolic substances. *Correspondent: Fax: +94 11 2 903203; e-mail: kapilas@kln.ac.lk International Journal of Food Science and Technology 2009, 44, 792–798 792 doi:10.1111/j.1365-2621.2008.01900.x Ó 2009 Institute of Food Science and Technology