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采用国产固定化假丝酵母脂肪酶,催化乙酯型和甘油酯型鱼油酯交换制备富含EPA和DHA的甘油酯型鱼油,得到EPA和DHA总量超过45%的甘油酯。以5g甘油酯型鱼油为反应底物之一,考察了反应温度、时间、酶加量、底物质量比及加水量五个因素对酯交换反应的影响,利用正交实验优化,得到最佳反应条件为:反应温度60℃,反应时间24h,底物质量比为5:4,加酶量为80U,不向反应体系中加入水分。在该条件下得到的甘油酯中EPA和DHA的含量分别为33.40%和13.10%,并且脂肪酶重复利用7次仍能达到工艺目标。 相似文献
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利用米曲霉脂肪酶催化甘油酯型鱼油和乙酯型鱼油的酯酯交换反应制备高含量EPA/DHA甘油酯,考察了底物摩尔比、反应温度、酶添加量和摇床转速对酶催化反应的影响,得到了最优酶催化反应条件:甘油酯型鱼油与乙酯型鱼油摩尔比1∶3,酶添加量14%,反应温度70℃,摇床转速150 r/min。在最优的酶催化反应条件下反应18 h,产物甘油酯型鱼油EPA和DHA含量可达到39.72%。在优化条件下对米曲霉WZ007菌丝体重复使用6次,甘油酯型鱼油产品中的EPA和DHA含量仍保持在34.51%。 相似文献
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选用磷脂酶A1为工具酶,以响应面为数值分析方法,在正己烷有机相中进行了大豆粉末磷脂水解制备溶血磷脂研究。探讨了反应时间,反应温度,加酶量,底物浓度,加水量,pH对其反应的影响。结果表明,溶血磷脂制备优化条件为:反应时间12.1 h,反应温度45℃,加酶量3%,底物浓度20.8%,加水量23.8%,pH 6。该条件下验证得溶血磷脂酸值(KOH)为77.8 mg/g。所得产物中磷脂酰胆碱和1-酰基-溶血磷脂酰胆碱含量分别为15.51%和3.99%,且2-酰基-溶血磷脂酰胆碱相对含量为19.6%。 相似文献
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以酸值为指标,通过单因素实验和正交实验确定了脂肪酶Bakezyme LFP在水相中水解大豆粉末磷脂的最佳工艺条件为:反应温度为50℃,反应时间为8h,p H为5.0,加酶量为8%,底物质量浓度为25mg/m L。在该工艺条件下,大豆磷脂水解产物酸值为65.2mg KOH/g。利用气相色谱-质谱联用仪分析了水解前后大豆磷脂的脂肪酸组成,结果表明水解后饱和脂肪酸含量明显下降,不饱和脂肪酸含量明显增加,说明脂肪酶Bakezyme LFP主要水解大豆磷脂1位上脂肪酸,具有磷脂酶A1的特性。利用高效液相色谱分析水解前后大豆磷脂的磷脂酰乙醇胺(PE)和磷脂酰胆碱(PC)含量,结果表明大豆磷脂中PE、PC发生水解,生成溶血磷脂。 相似文献
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在己烷体系中,采用磷脂酶A1催化卵磷脂乙醇解制备溶血卵磷脂。首先通过单因素试验分别考察了加酶量、加水量、底物比、温度和溶剂比对卵磷脂乙醇解制备溶血卵磷脂的影响,并在此基础上利用响应面法对反应工艺进行了优化。最终确定最佳工艺条件为:卵磷脂1.5 g,加酶量40μL/g(磷脂酶A1/卵磷脂),加水量25μL/g(水/卵磷脂(PC)),底物比:1∶3(PC/无水乙醇,mol/mol),温度30℃,溶剂比:1∶2(PC/正己烷,W/V),反应时间3.55 h,溶血磷脂转化率达98.3%。结果表明,磷脂酶A1可以催化磷脂酰胆碱乙醇解反应制备溶血磷脂酰胆碱。 相似文献
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Optimization of magnetic immobilized phospholipase A1 degumming process for soybean oil using response surface methodology 总被引:1,自引:0,他引:1
Dianyu Yu Ying Ma Lianzhou Jiang Walid Elfalleh Min Shi Lizhi Hu 《European Food Research and Technology》2013,237(5):811-817
This study focused on optimization of processing conditions of enzymatic degumming process for soybean oil using phospholipase A1 immobilized onto magnetic nanoparticles. A response surface methodology was developed and used to obtain optimum processing conditions. Four variables (temperature, reaction time, enzyme dosage, and added water) were investigated based on two response functions (phosphorus and free fatty acids (FFA) contents in degummed soy oil). For each response, second-order polynomial models were developed using multiple linear regression analysis. The optimum operating parameters of enzymatic degumming process were as follows: temperature of 56 °C, reaction time of 6.3 h, enzyme dosage of 0.10 g/kg, and added water of 2.13 ml/100 g. According to these optimum conditions, final residual phosphorus and FFA contents of degummed soy oil were reduced, respectively, to 10.38 mg/kg and 1.09/100 g using magnetic immobilized phospholipase A1. This finding is applicable for the physical refining of soybean oil or refining crude oils from field- and frost-damaged beans which have high content of non-hydratable phosphatides. 相似文献
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选择8种大孔树脂对磷脂酶A1进行固定化,结果表明,离子交换树脂D001的固定化效果最好,其优化的最佳条件为缓冲液pH5.0、酶添加量1.5mL/g、固定化时间4h,在该条件下获得的固定化酶活力为665.8U/g。将固定化酶用于菜籽油脱胶实验,经响应面优化确定最优脱胶条件为固定化酶添加量1.8g/kg、反应时间3.6h、反应温度51℃、反应pH5.5,在此条件下得到的脱胶油中磷含量为5.82mg/kg。将固定化酶重复脱胶5次后,仍保留初始酶活力的47.9%,脱胶油中磷含量为9.78mg/kg。 相似文献
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以大豆油和甲醇为原料,在K2CO3与相转移催化剂四丁基溴化铵(TBAB)作用下,合成生物柴油。考查相转移催化剂种类及用量、K2CO3用量、反应时间、醇油物质量比和反应温度对生物柴油产率影响;实验结果表明,制备生物柴油最佳条件为:TBAB用量为大豆油质量0.6%、K2CO3用量为大豆油质量1.5%、醇油物质量比为6∶1、反应时间为20 min、反应温度为40℃;在此条件下,制备生物柴油产率可达95%以上。 相似文献
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Partial hydrolysis of soybean oil catalyzed by phospholipase A1 (Lecitase Ultra) in a solvent-free system was carried out to produce a diacylglycerol (DAG)-enriched soybean oil. Five reaction parameters of partial hydrolysis were investigated. The upper oil layer of the reaction mixture was molecularly distilled at 150C to yield a DAG-enriched oil with 42.64 (wt%) of DAGs. DAG-enriched oil was distilled a second time at 250C to yield a DAG oil with 78.68 (wt%) of DAGs. The composition of acylglycerols in the DAG-enriched soybean oil was determined by high-performance liquid chromatography (HPLC) and HPLC/electrospray ionization/mass spectrometry. The released fatty acids from the partial phospholipase A1 hydrolysis of soybean oil showed a higher saturated fatty acid content than that of the raw material. Compared with other lipase-catalyzed processes, this new phospholipase A1 preparation has the advantage of reducing production of monoacylglycerol byproduct.
Diacylglycerols (DAGs) are esters of glycerol in which two of the hydroxyl group are esterified with fatty acids. Studies on both animals and humans have shown the beneficial health effects of DAG. DAG is a generally-regarded-as-safe foodstuff by the U.S. Food and Drug Administration and is approved as a substitution for triacylglycerol in fats and oils in many developed countries. In this work, partial hydrolysis catalyzed by phospholipase A1 (Lecitase Ultra) in a solvent-free system was firstly used to produce DAG-enriched soybean oil. Compared with the lipase-catalyzed process, this new phospholipase A1 showed the advantage of low cost and low byproduct monoacylglycerol production. The new process has a potential application in the commercial production of DAG oil. 相似文献
PRACTICAL APPLICATIONS
Diacylglycerols (DAGs) are esters of glycerol in which two of the hydroxyl group are esterified with fatty acids. Studies on both animals and humans have shown the beneficial health effects of DAG. DAG is a generally-regarded-as-safe foodstuff by the U.S. Food and Drug Administration and is approved as a substitution for triacylglycerol in fats and oils in many developed countries. In this work, partial hydrolysis catalyzed by phospholipase A
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摄食不同来源磷脂对大鼠脂质代谢及脑内磷脂脂肪酸组成的影响 总被引:1,自引:0,他引:1
研究了摄食不同来源磷脂对大鼠脂质代谢及其脑内磷脂脂肪酸组成的影响。雄性SD大鼠按体重随机分为大豆油对照组(添加9%)、牛乳磷脂组(添加5%)、大豆磷脂组(添加5%)、蛋黄磷脂组(添加5%),喂食3周。检测了血清总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)、游离脂肪酸(FFA)及肝脏TC、TG、磷脂(PL)的含量,并用气相色谱法测定了脑内磷脂脂肪酸的组成变化。结果显示:与大豆油对照组相比,3种磷脂均不同程度提高了大鼠体重、脏器指数,蛋黄磷脂效果显著;3种磷脂不同程度降低了血清TC、TG和FFA含量,牛乳磷脂降低血清FFA显著,大豆磷脂降低血清TC、TG显著,蛋黄磷脂降低FFA显著,大豆磷脂显著提升了血清HDL-C含量;3种磷脂不同程度降低了肝脏TC、TG、PL含量,牛乳磷脂与大豆磷脂降低肝脏TG、TC显著,而蛋黄磷脂降低肝脏TG显著;3种磷脂对脑内磷脂脂肪酸组成的影响各不相同,牛乳磷脂显著提高了脑内磷脂饱和脂肪酸含量,而大豆磷脂和蛋黄磷脂提高了DHA等多不饱和脂肪酸含量。研究表明,3种磷脂均有降血脂、肝脂作用,以大豆磷脂作用尤为明显,大豆磷脂和蛋黄磷脂的益智作用可能优于牛乳磷脂。 相似文献
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以大豆油和单甘酯为原料,在无溶剂体系中利用固定化脂肪酶Novozym 435催化合成甘油二酯。通过单因素实验和响应面实验研究反应温度、底物摩尔比、反应时间和酶添加量对甘油二酯含量的影响。结果表明:4个因素对甘油二酯含量影响的大小依次为反应温度、反应时间、酶添加量、底物摩尔比;合成甘油二酯的最佳工艺条件为大豆油与单甘酯摩尔比1∶2、酶添加量9%、反应温度83℃、反应时间6. 5 h,在此条件下甘油二酯含量为(51. 2±0. 2)%。 相似文献