Abstract:In order to promote the application of phytosterol ester，a novel catalyst was developed on the basis of traditional enzymatic synthesis method.Pickering emulsion catalyst （CRL@PE）with two-phase structure was constructed using isoctane and Candida rugosa lipase solution and employing nanotube as emulsifier.CRL@PE was identified as oil/water type with the droplet diameter ranging from 40 μm to 60 μm by optical microscopy，scanning electron microscopy and confocal microscopy.Then CRL@PE was used to catalyze the synthesis of βsitosterol linolenic acid ester with β-sitosterol and α-linolenic acid as substrates.The effects of water fraction，molar ratio of phytosterol to linolenic acid，enzyme dosage，temperature and reaction time on the conversion efficiency of phytosterols were studied by single factor experiment.The maximum conversion efficiency was 93.2 % under the optimal process parameters：water fraction of 4.0 %，molar ratio of linolenic acid to phytosterol of 2 ∶1（phytosterols of 30 μmol），enzyme dosage of 12 U，temperature of 30 ℃，and reaction time of 12 h.The conversion efficiency of phytosterol was 90.06% after CRL@PE reused 10 times and 77.3 % after 15 times reused，showing CRL@PE owned good stability.In addition，CRL@PE also had good thermal stability，but was more sensitive to temperature changes.