specific lipase(PSL) catalyzed glycerolysis of lard was performed in microemulsions containing sodium bis(2 ethylhexyl) sulfosuccinate(AOT) and a combination of water and glycerol as the polar components. The effects ...specific lipase(PSL) catalyzed glycerolysis of lard was performed in microemulsions containing sodium bis(2 ethylhexyl) sulfosuccinate(AOT) and a combination of water and glycerol as the polar components. The effects of reaction conditions and system parameters on the yield of monofattyacylglycerols have been investigated and the optimum conditions of syntheses of monofattyacylglycerols were established. The reactions were carried out at 34 ℃, iso octane being the best hydrocarbon. The other optima were established as follows: pH, 7 0; water content(in mass % of the system), 0 8; AOT content 5%; glycerol content 2 5%, and the monofattyacylglycerols yield herein was 17 3%. Maximum yield of monofattyacylglycerols is obtained at optimum molar ratio of (water+glycerol)/surfactant 6 3, which corresponds to droplet size of ca. 7 2 nm.展开更多
目的建立检测天花粉中氨基酸的高效反向胶束电动毛细管色谱-直接紫外法,并进行验证。方法样品分离采用未涂层毛细管(75μm×60 cm,有效长度为49.5 cm),通过运行缓冲液,在一定电压下进样,检测波长为200 nm,样品浓度为50μg/m L,操作...目的建立检测天花粉中氨基酸的高效反向胶束电动毛细管色谱-直接紫外法,并进行验证。方法样品分离采用未涂层毛细管(75μm×60 cm,有效长度为49.5 cm),通过运行缓冲液,在一定电压下进样,检测波长为200 nm,样品浓度为50μg/m L,操作温度为25℃。对分离条件中运行缓冲溶液p H(10、11和12)、缓冲体系浓度(40 mmol/L KH_2PO_4-110 mmol/L Na OH、60 mmol/L KH2PO4-130 mmol/L Na OH、70 mmol/L KH_2PO_4-140 mmol/L Na OH)、缓冲液阳离子表面活性剂浓度[0.2、0.6、1、1.2 mmol/L十六烷基三甲基氯化铵(cetyltrimethylammonium chloride,CTAC)]、缓冲溶液有机添加剂浓度(5%、10%、15%、20%乙腈)、进样方式(电动进样:-10 k V进样5 s,压力进样:34.5 k Pa进样5 s)、分离电压(15、20、25 k V)进行优化。同时验证方法的线性、精密性及准确性。采用最适条件检测供试品天花粉中3种氨基酸分离情况。结果最适检测条件为:运行缓冲液为5%(v/v)乙腈、1 mmol/L CTAC、60 mmol/L KH2PO4-130 mmol/L Na OH(p H 11);压力进样:34.5 k Pa×5 s,分离电压:20 k V。瓜氨酸、天冬酰胺和γ-氨基丁酸3种氨基酸的峰面积和浓度均呈良好的线性关系,R^2均>0.99;峰面积RSD分别为4.7%、4.5%和3.8%,迁移时间RSD分别为0.62%、0.93%和1.10%;加标回收率在82.48%~111.16%之间。该方法可有效分离天花粉中的3种氨基酸。结论本实验建立的方法快速有效,且具有良好的精密性及准确性,可用于天花粉中氨基酸的快速测定。展开更多
文摘specific lipase(PSL) catalyzed glycerolysis of lard was performed in microemulsions containing sodium bis(2 ethylhexyl) sulfosuccinate(AOT) and a combination of water and glycerol as the polar components. The effects of reaction conditions and system parameters on the yield of monofattyacylglycerols have been investigated and the optimum conditions of syntheses of monofattyacylglycerols were established. The reactions were carried out at 34 ℃, iso octane being the best hydrocarbon. The other optima were established as follows: pH, 7 0; water content(in mass % of the system), 0 8; AOT content 5%; glycerol content 2 5%, and the monofattyacylglycerols yield herein was 17 3%. Maximum yield of monofattyacylglycerols is obtained at optimum molar ratio of (water+glycerol)/surfactant 6 3, which corresponds to droplet size of ca. 7 2 nm.
文摘目的建立检测天花粉中氨基酸的高效反向胶束电动毛细管色谱-直接紫外法,并进行验证。方法样品分离采用未涂层毛细管(75μm×60 cm,有效长度为49.5 cm),通过运行缓冲液,在一定电压下进样,检测波长为200 nm,样品浓度为50μg/m L,操作温度为25℃。对分离条件中运行缓冲溶液p H(10、11和12)、缓冲体系浓度(40 mmol/L KH_2PO_4-110 mmol/L Na OH、60 mmol/L KH2PO4-130 mmol/L Na OH、70 mmol/L KH_2PO_4-140 mmol/L Na OH)、缓冲液阳离子表面活性剂浓度[0.2、0.6、1、1.2 mmol/L十六烷基三甲基氯化铵(cetyltrimethylammonium chloride,CTAC)]、缓冲溶液有机添加剂浓度(5%、10%、15%、20%乙腈)、进样方式(电动进样:-10 k V进样5 s,压力进样:34.5 k Pa进样5 s)、分离电压(15、20、25 k V)进行优化。同时验证方法的线性、精密性及准确性。采用最适条件检测供试品天花粉中3种氨基酸分离情况。结果最适检测条件为:运行缓冲液为5%(v/v)乙腈、1 mmol/L CTAC、60 mmol/L KH2PO4-130 mmol/L Na OH(p H 11);压力进样:34.5 k Pa×5 s,分离电压:20 k V。瓜氨酸、天冬酰胺和γ-氨基丁酸3种氨基酸的峰面积和浓度均呈良好的线性关系,R^2均>0.99;峰面积RSD分别为4.7%、4.5%和3.8%,迁移时间RSD分别为0.62%、0.93%和1.10%;加标回收率在82.48%~111.16%之间。该方法可有效分离天花粉中的3种氨基酸。结论本实验建立的方法快速有效,且具有良好的精密性及准确性,可用于天花粉中氨基酸的快速测定。
