Indrawati I, Van Loey A M, Ludikhuyze L R, Hendrickx M E
Laboratory of Food Technology, Department of Food and Microbial Technology, Catholic University of Leuven, Kardinaal Mercierlaan 92, B-3001 Heverlee, Belgium.
Biotechnol Prog. 1999 Mar-Apr;15(2):273-7. doi: 10.1021/bp990007o.
The objective of this investigation was to study kinetically the effect of pressure and temperature either as a single, as a combined, or as a sequential action on lipoxygenase (LOX) inactivation in crude green beans extract. The LOX isozymes in green beans extract had a different heat sensitivity but a similar pressure stability: two fractions following apparent first-order reactions, i.e., a heat-labile fraction and a heat-stable fraction, were observed in studies on its thermostability, whereas only one fraction following a first-order reaction was noticed in studies on its pressure stability. At ambient pressure, irreversible LOX inactivation was studied in a temperature range from 55 to 70 degrees C. At room temperature, pressures around 500 MPa were required in order to inactivate LOX in green beans extract. The effect of a pressure or a thermal pretreatment on LOX thermo- or barostability, respectively, was also investigated but no significant differences in inactivation kinetics due to the pretreatment were observed.
本研究的目的是从动力学角度研究压力和温度单独作用、联合作用或顺序作用对生绿豆提取物中脂氧合酶（LOX）失活的影响。绿豆提取物中的LOX同工酶具有不同的热敏感性，但压力稳定性相似：在其热稳定性研究中观察到两个遵循表观一级反应的组分，即热不稳定组分和热稳定组分，而在其压力稳定性研究中仅观察到一个遵循一级反应的组分。在常压下，在55至70摄氏度的温度范围内研究了LOX的不可逆失活。在室温下，需要约500 MPa的压力才能使绿豆提取物中的LOX失活。还分别研究了压力预处理或热预处理对LOX热稳定性或压力稳定性的影响，但未观察到预处理导致的失活动力学有显著差异。
