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利用响应面试验对在溶剂体系中脂肪酶Lipozyme RM IM催化玉米胚芽油与阿魏酸酸解制备阿魏酰基脂肪酰基结构酯的反应条件进行优化。在摇床转速为220 r/min的条件下,选取投料比(阿魏酸与玉米胚芽油质量比)、反应温度、反应时间3 个因素作为考察对象,以阿魏酸转化生成阿魏酰基脂肪酰基结构酯的得率为考察指标,运用Design-Expert软件的星点设计功能进行试验设计并对结果进行分析。结果表明,3 个因素均为影响阿魏酸酯化的显著因素;经响应面分析可确定最优值为投料比8.9∶1(g/g)、反应温度76.0 ℃、反应时间28.1 h。该条件下的平均得率达59.1%,与响应面拟合方程的得率预测值58.8%吻合良好。在煎炸过程中新制备的结构酯产生较低的聚合物,同时其具有较高的贮藏稳定性。 相似文献
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以三丁酸甘油酯和阿魏酸乙酯为原料,采用酶催化方法合成阿魏酰丁酸酯,通过单因素实验和正交实验研究溶剂体系、脂肪酶种类、溶剂配比、底物(三丁酸甘油酯与阿魏酸乙酯)摩尔比、反应温度、反应时间对阿魏酰丁酸酯转化率的影响,优化反应条件。结果表明:合成阿魏酰丁酸酯的最佳反应条件为脂肪酶Novozym 435为催化剂,酶添加量50 mg/m L,[EMIM][TF2N]-甲苯溶剂体系,[EMIM][TF2N]与甲苯质量体积比1∶1,反应温度50℃,底物摩尔比3∶1,反应时间6 d。在最佳反应条件下,阿魏酰丁酸酯转化率达76.24%。 相似文献
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王新颖孙尚德吕亚萍郭静静毕艳兰马传国 《中国油脂》2020,45(5):117-122
阿魏酸主要来自米糠加工副产物谷维素,是一种酚酸,具有抗氧化、抗癌以及清除自由基等多种生理功能,但阿魏酸的水溶性和脂溶性比较差,限制了其应用。综述了阿魏酸的生理功能特性、制备方法,以及在亲水性和亲脂性环境体系中高值化改性、利用进展,为阿魏酸及其衍生物的合成和应用提供了一定的理论基础,可扩大阿魏酸的应用范围,同时有利于提高米糠的利用价值。 相似文献
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采用响应面法对脂肪酶Lipozyme 435在无溶剂体系中催化中链甘三酯(MCT)和大豆油酯交换反应合成中长链甘三酯的反应条件进行优化,并采用超高压液相色谱-飞行时间质谱在正离子模式下对反应产物的甘三酯构型进行分析。结果表明:反应温度和反应时间对中长链甘三酯含量具有极显著性影响(P0.01)。最佳反应条件为大豆油与MCT质量比60∶40,反应时间4.36 h,反应温度89℃,加酶量(以底物质量计)5.5%。在此条件下,中长链甘三酯含量达到84.15%。CyCyL、CyCyLn、LOCy、LPCy、OOCy和LOCa为反应产物的主要甘三酯构型。 相似文献
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以Lipozyme TLIM催化茶油和共轭亚油酸乙酯制备共轭亚油酸(conjugated linoleic acid,CLA)结构脂,并调控酰基迁移反应以制备Sn-2位含CLA的结构脂。通过响应面法研究反应温度、水分活度、反应时间和底物物质的量比对总CLA键入量和酰基迁移的影响,并优化反应条件。本实验得到的结构脂中含有36.97%的总CLA,其中12.54%的CLA分布在Sn-2位,所得总CLA及Sn-2位的CLA键入量均高于文献报道。 相似文献
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酶促酸解合成结构脂具有显著的优越性,其中酰基迁移副反应是结构脂合成中亟需研究和控制的关键。对酶催化酸解反应中酰基迁移的理论和实践研究进行综述,归纳总结温度、时间、酶、载体、水分活度、溶剂、底物比、甘油酯结构等因素对酰基迁移的影响。目前,对酰基迁移的研究主要在酶促反应水平上,机理尚不深入,且优化酶促酸解条件提高接入率、产率与减少酰基迁移是不可兼得的矛盾关系。今后需要进行酰基迁移在复杂体系下的影响机制和评测方法的深入研究,以期更高效地开发特殊用途的结构脂产品。 相似文献
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肖乾煌徐雨茜熊华胡蒋宁朱雪梅张钰岩 《中国油脂》2020,45(3):62-67
以三棕榈酸甘油酯(PPP)和油茶籽油游离脂肪酸(FFA)为底物制备1,3-二油酸-2-棕榈酸甘油酯(OPO)结构脂为反应模型,以专一性脂酶Lipozyme RM IM为催化剂,研究不同有机溶剂(正己烷、丙酮、叔丁醇)、不同反应时间(0、2、4、6、8 h)、不同水分活度(a_w)(0.11、0.53、0.97)对酰基迁移的影响。结果表明:在3种溶剂中,丙酮的反应环境下酰基迁移发生率最低且油酸的键入率最高;在不同溶剂、不同水分活度的条件下,均在a_w为0.53时sn-2位棕榈酸和sn-1,3位油酸的含量较高,说明a_w影响脂肪酶的1,3位置选择性强弱决定于a_w的高低。鉴于结构脂制备过程中的绿色环保安全角度,可以采用无溶剂体系但是应较好地控制反应体系的a_w以抑制酰基迁移。 相似文献
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Enzymatic transesterification of fractionated rice bran oil with conjugated linoleic acid: Optimization by response surface methodology 总被引:1,自引:0,他引:1
Rice bran oil (RBO) was fractionated at a low temperature (−16 °C) and the yield of fractionated solid (S-RBO) and liquid (L-RBO) phase were 66.5 and 33.5 g/100 g, respectively. The L-RBO contained more unsaturated fatty acids (81.8%) than S-RBO (76.1%). Response surface methodology (RSM) was used to determine the effects of three variables (water activity of lipase, reaction temperature and time) on the lipase catalyzed incorporation of conjugated linoleic acid (CLA) into L-RBO. We used CLA as the acyl due to its purported health benefits. The transesterified lipid (TL) contained palmitic (13.5%), oleic (37.5%), linoleic (26.6%) and CLA isomers (20.7%), respectively. According to ridge analysis, optimal reaction conditions for water activity of lipase, reaction temperature and time were 0.177, 55.66 °C and 29.25 h, respectively, for producing TL with maximum incorporation of CLA. The coefficient of determination (R2=0.94) showed that the fitted model explained 94% of the observation. The TL was reproduced to confirm the experimental incorporation with the estimated value. The data showed that the experimental response was reasonably close to the estimated response. These results suggested that RSM can be used to optimize lipase-catalyzed incorporation of CLA into the fractionated L-RBO. 相似文献
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Begum Elibal H. Funda Suzen H. Ayse Aksoy Guldem Ustun Melek Tuter 《International Journal of Food Science & Technology》2011,46(7):1422-1427
Structured lipids containing conjugated linolenic acid (CLNA) were produced separately by enzymatic acidolysis reaction of corn and canola oils (CAO) with bitter gourd (Momordica charantia L) seed oil fatty acids [bitter gourd seed oil fatty acids (BGFA)]. Reactions were conducted using a commercial immobilised sn‐1,3‐specific lipase from Thermomyces lanuginosa (Lipozyme TL IM) in hexane. The effects of reaction time, substrate molar ratio, temperature and enzyme amount on incorporation yield of CLNA were investigated and optimised by response surface methodology with three‐level, two‐factor face‐centred cube design. When reactions were conducted using 10% enzyme for 3 h, the optimum reaction conditions were found for corn oil (CO) as 53.5 °C and 5.9:1 BGFA/CO molar ratio. At these conditions, the incorporation of CLNA into CO was determined as 41.4%. However, CLNA incorporation into CAO was resulted as 37% at optimum conditions which were 54.2 °C and 6.8:1 BGFA/CAO molar ratio. 相似文献
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为了降低棉粕的毒性及最大限度地提取棉酚,以棉仁为原料,以甲醇为溶剂,采用溶剂浸出法对棉仁中游离棉酚的提取工艺进行研究。在单因素试验的基础上,通过响应面法对工艺条件进行优化。结果显示各因素影响游离棉酚提取率的主次顺序为:提取时间料液比提取温度搅拌速率;得到的最佳工艺条件为:料液比1∶24,提取温度35℃,提取时间42 min,搅拌速率2 600 r/min,提取次数2次(即先以料液比1∶12提取,提取21 min,再以料液比1∶12提取,提取21min);在最佳工艺条件下,游离棉酚的提取率为68.9%±0.81%,其纯度为81.9%±0.85%。此时,棉粕中游离棉酚残留量为839.7 mg/kg,小于饲料卫生标准(GB 13078—2001)中所规定的棉籽饼、粕中允许的游离棉酚最大残留量1 200 mg/kg。 相似文献
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响应面法优化无溶剂体系磷脂酶A1催化酯化制备低聚甘油酯的研究 总被引:1,自引:0,他引:1
以工业油酸和低聚甘油为原料,经磷脂酶A1(Lecitase Ultra)催化酯化制备低聚脂肪酸甘油酯。利用响应面法优化实验条件,研究反应时间、反应温度、加酶量、加水量以及底物摩尔比值(工业油酸和低聚甘油摩尔比值)对其酯化率的影响。得出最佳反应条件为:反应温度45℃,加酶量1.6wt%(占底物总质量),加水量4wt%(占底物总质量),反应时间12h,底物摩尔比值为1:1。最佳条件下酯化反应平均酯化率可达到56.6%。采用HPLC-ESI质谱通过检测相对分子质量验证了部分低聚甘油酯产物的种类。 相似文献
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目的 通过响应面法优化大米中镉的提取条件,建立大米中镉脱除工艺,最终达到降低米制品原料大米中镉含量。方法 以镉提取率为指标筛选大米中镉脱除方法,选择市售含镉大米为试验样品,四种食品级有机弱酸作为提取剂,以提取酸溶液浓度、提取时间、料液比和大米粉粒度为自变量,进行单因素提取研究,同时结合响应面试验设计,获得大米中镉脱除的最佳条件。结果 大米中镉脱除的最佳条件为乙酸浓度4.2%,提取时间11 min、液料比13:1(mL/g)和大米粉粒度细于50目,此条件下大米镉平均提取率为98.67%。结论 该试验模型合理,优化的提取方法切实可行,通过采用优化后的最佳镉提取条件,实现了脱除或降低原料米中镉,为镉污染大米的镉去除研究提供了一种科学方法。 相似文献
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Jülide Gökçe Neşe Şahin Yeşilçubuk Güldem Üstün 《International Journal of Food Science & Technology》2013,48(7):1383-1389
Low‐calorie structured lipids (SLs) were produced from Echium seed oil and lauric acid by enzymatic acidolysis reactions. Lipozyme® RM IM, commercially immobilised sn‐1,3 specific lipase derived from Rhizomucor miehei, was used in the reactions. The effects of substrate molar ratio and reaction time on incorporation of lauric acid were investigated and optimised by response surface technology (RSM) with five‐level, two‐factor central composite design. Good quadratic model was obtained for the response [lauric acid (%) incorporation]. Highest lauric acid incorporation into Echium oil was obtained at 5:1 lauric acid/Echium oil molar ratio and at 4‐h reaction time. The model was verified at these conditions and furthermore scale‐up synthesis of SLs was performed. At these conditions, SL contained predominantly lauric acid (42.8%), oleic acid (9.9%), linoleic acid (10.8%), α‐linolenic acid (15.1%), γ‐linolenic acid (7.5%) and stearidonic acid (8.5%) with% 64.4 of PUFA at sn‐2 position in gram‐scale synthesis. 相似文献