大豆甾醇硬脂酸酯的合成工艺研究

Study on the Synthesis of Soybean Sterol Stearate

植物甾醇是一种新资源食品,可以有效降低人体血清中的胆固醇含量。为改善植物甾醇的溶解性与生物利用率,常用酯化的方法提高其脂溶性。采用正相高效液相色谱法对大豆甾醇硬脂酸酯进行定性定量分析。以大豆甾醇硬脂酸酯产率为考察指标,研究催化剂种类、醇酸物质的量的比、催化剂用量、反应温度和反应时间对大豆甾醇硬脂酸酯产率的影响。在单因素试验的基础上,进行正交试验得到合成大豆甾醇硬脂酸酯的最佳工艺条件,并进行验证。大豆甾醇硬脂酸酯的最佳合成工艺条件:以硫酸氢钠为催化剂,催化剂用量为5%(大豆甾醇与硬脂酸的质量之和),大豆甾醇与硬脂酸的物质的量的比为1∶1.2,反应温度为130℃,反应时间为8 h,大豆甾醇硬脂酸酯的产率为95.00%,大豆甾醇转化率为97.29%。在此条件下合成的大豆甾醇硬脂酸酯产品经纯化后,以红外光谱法进行表征。以化学法合成了高纯度的大豆甾醇硬脂酸酯产品,为植物甾醇酯的高效生产与开发利用提供了技术支持。

Phytosterol is a new resource food,which can effectively reduce the cholesterol content in human serum. To improve the solubility and bioavailability of phytosterols in lipids,esterification is often used to improve their hydrophobicity. The soybean sterol stearate was synthesized by chemical esterification method,and Normal-phase High Performance Liquid Chromatography was used for qualification and quantitation the products. The effect of catalyst type,molar ratio of soybean sterols to stearic acid,catalyst amount,reaction temperature and reaction time on the yield of soybean sterol stearate was investigated. On the basis of single-factor experiment,orthogonal experiment was carried out to obtain the optimum conditions for soybean sterol stearate synthesis. The optimal conditions were shown as follows: sodium hydrogen sulphate as catalyst,catalyst amount 5%(the mass of soybean sterols and stearic acid),molar ratio of soybean sterols to stearic acid 1∶1.2,reaction temperature 130 ℃,and reaction time 8 h. Under the above optimal conditions,the yield of soybean sterol stearate was up to 95.00%,while the conversion yield of soybean sterols was 97.29%. The afforded soybean sterol stearate products were purified and characterized by Infrared Spectroscopy.High purity soybean sterol stearate products were synthesized by chemical method in this paper,which will provided technical support for the efficient production,development and utilization of phytosterol esters.