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We compared four esterifiable enzymes.The lipase Novozym 435 possessed the highest activity for the conjugated linoleic acid esterification during the synthesis of triglycerides.The triglycerides were synthesized by esterification of glycerol and conjugated linoleic acid(CLA) in a no-solvent system using lipase catalysis.We investigated the effects of temperature,enzyme concentration,water content,and time on esterification.Enzyme and water concentrations of up to 1% of the total reaction volume and a syste... 相似文献
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A bacterium hydrolyzing carboxymethylcellulose, isolated from Antarctic sea ice, was identified as Pseudoalteromonas sp. based on 16S rDNA gene sequences and named as Pseudoalteromonas sp. AN545. The extracellular endo-1,4-β-glucanase AN-1 was purified successively by ammonium sulfate precipitation, DEAE-Sepharose ion exchange chromatography and Sephadex G-75 gel filtration chromatography. The molecular mass of AN-1 was estimated to be 47.5 kDa utilizing SDS-PAGE and gel chromatography analysis. AN-1 could hydrolyze caboxymethylcellulose, avicel and β-glucan, but not cellobiose, xylan and p-Nitrophenyl-β-D-glucopyranoside. The optimal temperature and pH for the β-glucanase activity of AN-1 were determined to be at 30°C and pH 6.0, respectively. AN-1 was stable at acidic solutions of pH 5.0-6.5 and temperatures below 30°C for 1 h. Moreover, the specific activity was enhanced by Ca2+ and Mg2+, and inhibited by Cu2+. The kinetic parameters Michaelis constant (Km) and maximum velocity (Vmax) of AN-1 were 3.96 mg/mL and 6.06×10-2 mg/(min·mL), respectively. 相似文献
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交酯化法制备鱼油脂肪酸乙酯的研究 总被引：4，自引：0，他引：4
研究了用交酯化法制备鱼油脂肪酸乙酯的工艺，分析了原料鱼油的质量，催化剂NaOH和乙醇用量对乙酯化的影响，结果表明，原料鱼油在低酸值、低过氧化值、低水分时对乙酯化反应是有利的，催化剂NaOH的用量为原料鱼油的0.3%，无水乙醇的用量高产田原料鱼油的60%时是比较经济的。 相似文献
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海藻原生质体融合及杂交技术的研究进展 总被引：1，自引：0，他引：1
根据藻类细胞脱壁程度的不同 ,Ａｄａｍｉｃｈ将脱壁后的藻细胞分为原生质体（Ｐｒｏｔｏｐｌａｓｔ）和原生质球（Ｓｐｈｅｒｏｐｌａｓｔ）。原生质体是指质膜外的细胞壁和包被层全部除去而保持其余细胞组分的任何基因型的藻细胞 ;原生质球是指细胞壁被全部或部分除去 ,仍保持质膜外包被层的含全部细胞内组分的部分。当细胞壁去除后 ,原生质体具有以下特征 :（１）无细胞壁障碍 ,可对膜、细胞器进行基础研究 ,同时可进行遗传操作。（２）具有全能性 ,能在人工条件控制下 ,进行大量快速繁殖。（３）可诱导融合 ,形成杂种细胞 ,为体细胞杂交… 相似文献
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