Research On Enzymatic Synthesis And Purification Of Phytosterols Palmitate And Its Physicochemical Properties

Phytosterol have blood lipids-reducing, cholesterol-lowering activity and prevention ofcardiovascular diseases. However, the poor fat-solubility of phytosterol has limited theirapplication in food and pharmaceutical industry. Iorder to improve solubility of freephytosteorls in edible fats/oils, preparation technology, analytic methods, bioactivities andProperties of phytosterols ester were studied systatiaclly in this dissertation. The main resultsare shown as follows:In organic phase system using Lipase PPL、Lipase RMIM and Novozyme435as catalyst,immobilized lipase catalytic plant sterol and palmitic acid synthesis good fat-solublepalmitate, and through the orthogonal experiment optimization technological conditions ofenzymatic esterification. The highest phytosterols palmitate esterification degree of39.4%was obtained under the selected conditions:0.27g plant sterol,0.34g palmitic acid,600mgmolecular sieves and10%Novozyme435at150rpm and55℃for72h in15mL of n-hexane.The TLC results showed that successful separation of phytosterol, palmitic acid andphytosterols palmitate was performed by using petroleum ether(60-90)/anhydrousether/acetic acid（90/10/1，v/v/v）as the developer. The conditions of silica gel columnchromatography were as follows:silica gel(from80~100mesh)as column packing, petroleumether(60-90)/anhydrous ether/acetic acid（90/10/1，v/v/v）as eluent, eluent flow rate60mL/h,column temperature30℃, column packed height70cm(column1000mm×30mm i.d). Underthese conditions, the purification recovery was above90%.Researched on the fat-solubility and antioxidant activity of phytosterols palmitate: Studyon the solubility of phytosterol and phytosterols palmitate in plant oil and fish oil at60℃.Fat-solubility of plant sterol was increased by4times in fish oils after etserification. Theantioxidation activity of phytosterol and phytosterols palmitate in fish oil was studied by thedetermination of POV of the fish oil. Their optimum concentration was0.05mg/g at40℃, theoptimum concentration of phytosterol and phytosteryl palmitate was0.50mg/g and0.10mg/gat80℃.