无溶剂体系酶催化合成富含共轭亚油酸甘油脂的研究

采用中心组合设计和响应面方法，研究了无溶剂体系中脂肪酶催化共轭亚油酸（CLA）与油脂反应的主要影响因素。建立了二级响应面模型，模型的复相关系数为0．90。甘油酯中CLA含量随温度、反应时间、底物配比增加而提高，反应时间影响最为显著。水分含量对酸解反应具有负影响，反应温度及反应时间与水分含量有交互作用。优化的反应条件为：反应时间为8－10h，温度40－45℃，酶量200U／g油脂，底物配比1：2．5，水含量1．0％。在优化条件下，红花油中共轭亚油酸含量可达31．47％。脂肪酶催化10，12－十八碳二烯酸反应优于9，11－十八碳二烯酸。     

脂肪一步催化氨化和脱水制备脂肪腈的研究——(二)工艺部分

详细介绍了脂肪一步催化氨化和脱水制备脂肪腈的工艺流程。并考察了催化剂用量、氨流量、反应温度及分馏柱温度或填充物对反应活性的影响。结果表明,最佳反应条件是:催化剂用量为3％～5％,氨流量800(L/h·kg油脂),末段反应温度270℃以上,分馏柱温度80～86℃,分馏柱填充物用脱水性物质。实验最好的反应结果为腈得率约92％。     

响应面法优化脂肪酶富集金枪鱼油中二十二碳六烯酸甘油酯工艺研究

以金枪鱼副产物为原料提取精炼鱼油,研究了皱褶假丝酵母脂肪酶（Candida Rugosa）富集金枪鱼油二十二碳六烯酸（ Docosahexaenoic Acid, DHA）甘油酯的工艺条件。在单因素实验的基础上选取水油质量比、脂肪酶添加量、反应温度和时间4个因素为自变量,以甘油酯中DHA、ω-3含量和甘油酯得率为响应值,采用中心组合（box–behnken）进行响应面实验设计和分析。结果表明,最佳条件为水油比1:1.7,脂肪酶添加量1%,反应温度50 ℃,反应时间3 h。在此条件下,甘油酯中DHA质量分数为35.55%,ω-3质量分数为42.25%,甘油酯得率为73.85%。本课题成功建立了甘油酯中DHA 、ω-3含量 (R2 = 0.8832) 和甘油酯得率(R2 = 0.9425) 的拟合模型。卡方检验分析表明这两种模型的预测值和实测值无显著性差异(P > 0.05)。     

脂肪一步催化氨化制备脂肪腈的研究——(一)催化剂部分

描述了脂肪一步氨化制脂肪睛的新方法。重点考察了催化剂制备方法对反应活性的影响。结果表明,在实验范围内,催化剂以十二烷基苯磺酸根为阴离子时,阳离子选铅较好;催化剂制备温度70℃最好;老化和干燥温度略低。     

Determination of Coenzyme Q<Subscript>9</Subscript> and Q<Subscript>10</Subscript> in Developing Palm Fruits

A series of biochemical changes took place as oil palm fruits developed into maturity. Among these are the active synthesis of glycerides as well as unsaponifiable compounds such as carotenes, vitamin E, sterols and squalene. Coenzyme Q₉ and Q₁₀ were found to be present at different stages of the oil palm fruits development. The presence of coenzyme Q₉ was detected as early as 4 weeks after anthesis (WAA) and its concentration diminished as the oil palm fruits ripen. Coenzyme Q₁₀ on the other hand, can only be detected from 12WAA onwards and its concentration remained at an elevated level throughout the remaining development period of the oil palm fruits. Their occurrence pattern suggested that there is a strong relationship between the concentration of coenzyme Q₉ and coenzyme Q₁₀ with the age of the oil palm fruits.     

Rapid determination of esterified glycerol and glycerides in triglyceride fats and oils by means of periodate method after transesterification

This paper describes an accurate method to determine esterified glycerol in the glycerides of edible fats and oils and, in general, in all triglyceride fat or oil. Esterified glycerol is released by means of a transesterification reaction with potassium hydroxide in methanol, which simultaneously produces fatty acid methyl esters. Free glycerol is oxidized selectively to formic acid and without any interference in the same environment in which the transesterification reaction occurs by the addition of periodate.     

Improved quantitative13C nuclear magnetic resonance criteria for determination of grades of virgin olive oils. The normal ranges for diglycerides in olive oil

A quantitative method was established to determine the presence and composition of mono-, di-, and triglycerides of olive oils of superior gradevia ¹³C NMR. The total diglyceride content and the ratio ofsn-1,2- andsn-1,3-diglycerides in extra virgin oils extracted from different olive cultivars were correlated with maturity. The correlation can be applied to identify the oils by variety. No monoglycerides were detected in the oils examined.     

Estimation of Docosahexaenoic Acid Glycerides in Schizochytrium sp. Oil by Open Column Chromatography and Reversed-phase HPLC

Column chromatography and reversed-phase HPLC using a Sepax BR-C18 column were applied for the analysis of glycerides in the docosahexaenoic acid (DHA) oil by Schizochytrium sp. The oil was detected under UV light after isocratic elution with 20 % 2-propanol/hexane (5:4, v/v) + 80 % acetonitrile. The correlation coefficients for the calibration of HPLC for DHA glycerides were in the range of 0.9958–0.9998. The accuracy was confirmed with recoveries of 93.47–102.25 %. DHA oil samples under different aeration rates were successfully analyzed and the content of the binding of DHA on the acylglycerol backbone was very low (1.81–4.21 %). However, the content of glycerides (tri-, di-, mono-) separated by column chromatography was more than 87.22 %. The glycerides were largely composed of triacylglycerides (TAG) (82.29–89.54 %), where higher content of TAG correlated to higher contents of DHA and TAG of DHA (TriDHA). In addition, the optimal aeration rate of 250 m³/h was obtained for TAG, DHA, and TriDHA production by Schizochytrium sp. with the temperature 30 ± 0.5 °C, impeller speed 85 ± 5 rpm and pressure 0.04 Mpa.     

溶剂体系酶催化酸解反应合成富含共轭亚油酸油脂的研究

研究了溶剂体系中脂肪酶催化共轭亚油酸(CLA)与油脂酸解反应制备富含共轭亚油酸油脂的影响因素考察了温度、底物配比、酶量、体系水分、无机盐等因素对酯交换反应的影响结果表明,适宜的工艺条件是:水含量0.5％, 底物配比2:1,温度50℃,酶量200U/g油脂,在上述条件下反应12h,花生油中共轭亚油酸含量可达18％左右研究了溶剂体系中脂肪酶对共轭亚油酸异构体的底物选择性,结果表明,脂肪酶催化10,12-十八碳二烯酸酸解反应优于9,11-十八碳二烯酸酸