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研究了以超临界二氧化碳为介质,假丝酵母脂肪酶催化月桂酸和正丁醇酯化的反应过程中,压力、温度、酶含水量、底物浓度和种类对于反应的影响。使用了陈惠晴等,于《清华大学学报》1999年第6期第31至34页所述的方法,研究发现,压力升高使酶中的水分减少,导致酶活力的下降。升高压力会使反应底物的溶解度增加,使反应速率提高。在34℃~60℃范围内,温度的升高,使反应速率上升。酶中含水质量分数为40%时,酶活性最高。正丁醇的浓度大于100mmolL-1,对酶产生抑制;月桂酸浓度小于40mmolL-1时,没有发现对反应的抑制。醇的分子体积越大,反应速率越小。醇的极性减小,反应速率增大。
The effects of pressure, temperature, enzyme content, substrate concentration and species on the reaction were studied in the reaction of esterification of lauric acid and n-butanol catalyzed by Candida lipase catalyzed by carbon dioxide. The use of Chen Huiju, etc., “Journal of Tsinghua University,” 1999 the sixth period, the method described on page 31 to page 34, the study found that the pressure increase in the enzyme to reduce the water, resulting in decreased enzyme activity. Increasing the pressure increases the solubility of the reaction substrate and increases the reaction rate. In the range of 34 ℃ ~ 60 ℃, the temperature increases, the reaction rate increases. Enzyme in the water content of 40%, the highest enzyme activity. N-Butanol concentrations greater than 100mmolL-1, inhibition of the enzyme; lauric acid concentration of less than 40mmolL-1, no inhibition of the reaction was found. The larger the molecular volume of alcohol, the smaller the reaction rate. The polarity of alcohol decreases and the reaction rate increases.