白鲢鱼肌肉脂肪氧合酶提取条件优化及酶学性质研究

王帮国; 林琳; 余振宇; 李洋; 姜绍通

doi:10.13386/j.issn1002-0306.2017.09.013

白鲢鱼肌肉脂肪氧合酶提取条件优化及酶学性质研究

Optimization of lipoxygenase extraction conditions in silver carp muscle and the study on its enzymatic properties

摘要

摘要: 本文以白鲢鱼肌肉为原料,通过单因素实验对白鲢鱼肌肉脂肪氧合酶(LOX)提取条件进行优化;用圆二色谱法和荧光光谱法对其贮藏稳定性、热稳定性、最适p H进行研究;探讨磷酸盐缓冲液p H、离子强度、二硫苏糖醇(DTT)和乙二胺四乙酸(EDTA)添加量对白鲢鱼肌肉LOX提取工艺的影响。结果表明,白鲢鱼肌肉LOX适宜提取条件为磷酸盐缓冲液p H7.8、离子强度50 mmol/L、EDTA和DTT添加量均为2 mmol/L,在此条件下提取白鲢鱼肌肉LOX的酶液浓度为(1.98±0.037)mg/m L,活力为(244.44±5.93)U。通过对LOX酶学性质研究可知,白鲢鱼肌肉LOX在常温条件下0~2 d内酶活性较为稳定,最适作用温度为40℃,最适p H为7.8。

Abstract: The extraction process and enzymatic properties of Lipoxygenase ( LOX) from silver carp muscle were evaluated.The extraction conditions of LOX were optimized by single-factor experiment and the storage stability, thermal stability, optimum p H of LOX were studied by circular dichroism and fluorescence spectroscopy.The effects of p H, ionic strength and the addition of EDTA, DTT on the enzyme activity and concentration of LOX were studied respectively.The results showed that the suitable extraction condition parameters were: p H7.8, ionic strength 50 mmol/L, EDTA 2 mmol/L and DTT 2 mmol/L, the enzyme concentration of LOX was ( 1.98 ± 0.037) mg/m L and the activity was ( 244.44 ± 5.93) U under that condition. Our present work showed that the enzyme activity of LOX was stable within 0² d under room temperature, the optimum p H was 7.8 and the optimum temperature was 40 ℃.