Optimization of adlay (Coix lacryma-jobi) bran oil extraction: Variability in fatty acids profile and fatty acid synthase inhibitory activities

Abstract Adlay (Coix lacryma-jobi) bran has recently attracted much attention because it is rich in neutral oil, which promises its potential usage as a health-promotion product. This study was firstly designed to select and optimize an optimum method to extract adlay bran oil (ABO). Secondly, differences of fatty acids profile and fatty acid synthase inhibitory activities between ABO and Kanglaite® injection (commercial adlay seeds oil) were determined to explore the potential application of ABO as an antitumor product. The optimized extraction conditions of ABO were ethanol-water extraction at AB particle size of 30.5 μm, pH of 7.0, ethanol volume of 30%, solid to liquid ratio of 1:5 (w/v), the temperature of 50 °C and reaction time of 2 h. After refining, the refined ABO had better properties than crude ABO except for the content of vitamin E. In addition, both crude and refined ABO extracted by ethanol-water had higher proportions of palmitic acid (C16:0) and linoleic acid (C18:2) to oleic acid (C18:1) than Kanglaite®. The fatty acid synthase inhibitory activities of crude ABO were higher than refined ABO and Kanglaite® injection at a dose of 10 μL/mL inhibition for 2 h under 25 °C. The results proved that crude ABO extracted by the ethanol-water method probably had a potential higher anticancer function than Kanglaite® injection. The results will provide a theoretical foundation in studying the mechanism of the anti-cancer effects of ABO. It can also reduce production and increase the economic value of adlay processing industry.