| Suaeda salsa is one of the wild resource in seashore salt marsh and inland of saline soil. It is also a dominant species of halophyte. The seeds oil of S. salsa is the good raw material of conjugated linoleic acid (CLA) with the specific physiological function. CLA are mixtures of several positional and geometric isomers of conjugated octadecadienoic(18:2) acid. CLAisomers have various physiological activities for their specific fatty acid chain. c9,t-ll CLA and tl0,c12 CLA are the main active isomers. They have different physiological mechanism. It is industrially produced by alkali conjugation in propylene glycol or ethylene glycol. The present technology contain certain safety problem. It is a developing trend that new safe solvent system and fractionation technology of CLAisomers are studied.CLA had been synthesized with S. salsa seed oil in glycerine solvent to solve the solvent safety problem. The CLA oxidative stability, enrichment of glycerides with conjugated linoleic acid via enzymatic method, fractionation of isomers by enzymatic method, body fat reduction and toxicology of CLA were investigated. Following conclusions can be made from the study.1. Techniques of the conjugated linoleic acid synthesis with S. salsa seed oil had been investigated in glycerine solvent system. The circled use of glycerine solvent was studied. Because of oil hydrolysis producing glycerine, the solvent system may be use repeatedly. The molecular geometric structures of CLA preparations were determined by GC-MS and GC-IR spectrum. CLA preparations contain mainly cis-and trans- double bonds. The CLA peak position of GC spectrum was determined by standard CLA. The results show that S. salsa oil is a kind of good raw material. The CLA content in the fatty acid preparations can be up to 70%. Optimal conditions correspond to temperature of 185-190癈, time of 2~3h, katalyst amount to oil of 20%, solvent amount to oil of 2~3 times.2. The oxidative stability of CLA and its principal effect factors were studied. The oxidative stability of CLA is inferior to oil. Transitional metals (Fe3+) play an extremely important role in catalyzing CLA oxidation. Several antioxidants and antioxidants mixture had been used to studythe anti-oxidation properties for CLA. BHT and BHA+BHT(1:1) are higher anti-oxidation abilities of CLA than other antioxidants. Vc,VE and citric acid can not restrain the oxidation of free CLA. VE and citric acid may speed-up the oxidation of free CLA. The transitional metals must avoid in press and preservation of CLA. The suitable antioxidants may improve the oxidative stability of CLA.3. Glycerides was produced via interesterification reactions of triglyceride and conjugated linoleic acid (CLA) by lipase from Candida antarctica (NOVOZYMR 435) in solvent system. The effects of temperature, ratio of substrates, enzyme content, inorganic salts, water content on the interesterification were investigated. It is shown that the optimized conditions are the enzyme concent 200U/g oil , water content in the system of 0.50% , the CLA oil ratio at 2.00 :1.00,termperature of 50 . The content of CLA is up to 18% when lipase catalyzed interesterification carried on 12h. The substrate selectivity of lipase (NOVOZYMR 435) had been examined in the interesterification of conjugated linoleic acid isomers in n-hexane. The lipase has a preference to the tlO,c12CLA than c9,t11CLA. The selectivity coefficient of the lipase (NOVOZYMR 435) on t10, c12-CLA is 1.34.4. Glycerides were produced vice interesterification reactions of triglyceride and conjugated linoleic acid(CLA) by lipase (Novozym 435) in free solvent. Response surface methodology base on central composite rotatable design was used to evaluate the influence of five major factors and their relationships. The effects of reaction time, temperature, substitute ratio, enzyme amount, water content on the interesterification were investigated. The best-fitting quadratic response surface model was determined by regression and backward elimination. The substrate sel...
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