大麦中脂肪酸氧化酶的活性

Study on activity of lipoxygenase in barley

作为氧化还原酶系之一的脂肪酸氧化酶,经氧化反应可形成啤酒老化醛类物质,对啤酒的风味稳定性产生一定影响。该文以大麦为研究对象,对脂肪酸氧化酶活性的原有测定方法进行了优化,并在此基础上分析了27种不同大麦品种中LOX的活性。通过实验可知,大麦中脂肪酸氧化酶活性的最佳测定温度为25℃;反应体系中最佳缓冲液pH值为8.0;最佳粗酶提取液添加量及底物浓度分别为50μL和5 mmol/L;此方法的3组重复性实验RSD值均小于5%,重现性RSD值为5.26%;不同大麦产地,生产年份及遗传基因型的大麦品种中,LOX活性存在显著性差异。

As one of the redox enzymes,some aging aldehydes are produced by lipoxygenase in the oxidation reaction,which may affect the flavor stability of beer. Herein,the original measurement of lipoxygenase was optimized and 27 different kinds of barley were researched. The result showed that the optimal reaction temperature was 25℃and the pH of optimal buffer solution in reaction system was 8. 0. The addition of extracted crude enzyme was 50μL and the concentration of substrates was 5mmol / L. Besides,the repeatability and reproducibility were respectively less than 5% and 5. 26%. The significant difference of lipoxygenase was found in the different fields,years and genetic types of barley.