A rapid, accurate method with high sensitivity and reproducibility, and having the advantage of a short incubation period under constant pH, has been developed for routine measurement of microbial lipase. Assembled from readily available and economical instrumental components, the apparatus includes a pH meter, a thermoelectric heating and stirring device, a motor-driven burette, and an automatic recorder. The reaction mixture, consisting of 5 ml of a 10% olive oil-gum arabic emulsion, 2 ml of 3 m NaCl, 2 ml of sodium taurocholate (15 mg/ml) of 0.075 m CaCl2, 5 ml of water, and 1 ml of enzyme solution, was adjusted to pH 8.0 and 37 C. The pH was maintained at a constant value by automatic addition of 0.01 n NaOH during the incubation period, which usually lasted 5 min. A lipase unit, derived from the use of this technique, may be defined as the number of microequivalents of acid liberated per minute under the specified conditions. The method was sensitive to 0.01 units. Various organisms tested produced 0.17 to 1.32 units per ml of the cell filtrate. An Arrhenius plot for staphylococcal lipase yielded 14,500 cal for function A (energy of activation).
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机译：已经开发出一种快速，准确的方法，具有较高的灵敏度和可重复性，并且具有在恒定pH下温育期短的优点，可用于常规测定微生物脂肪酶。该设备由容易获得且经济的仪器组件组装而成，包括pH计，热电加热和搅拌装置，电机驱动的滴定管和自动记录仪。反应混合物由5 ml的10％的橄榄油-阿拉伯胶乳液，2 ml的3 m NaCl，2 ml的0.075 m CaCl2的牛磺胆酸钠（15 mg / ml），5 ml的水组成将1ml酶溶液调节至pH 8.0和37℃。在温育期间，通常持续5分钟，通过自动添加0.01n NaOH将pH保持在恒定值。源自使用该技术的脂肪酶单位可以定义为在指定条件下每分钟释放的酸的微当量数。该方法对0.01个单位敏感。测试的各种生物每毫升细胞滤液产生0.17至1.32单位。 Arrhenius葡萄球菌脂肪酶图的功能A（活化能）产生14,500 cal。
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