热处理方式对大豆脂肪氧合酶活力和构象的影响  

Effects of Heating Treatment on the Activity and Conformation of Soybean Lipoxygenase

作　　者：孔月 孙立娜[1] 李妍慧 康子孟 何甜 吕文彪 徐福 张爽[1] 谢凤英[1] Kong Yue;Sun Lina;Li Yanhui;Kang Zimeng;He Tian;LüWenbiao;Xu Fu;Zhang Shuang;Xie Fengying(College of Food Science,Northeast Agricultural University,Harbin 150030)

机构地区：[1]东北农业大学食品学院,哈尔滨150030

出　　处：《中国食品学报》2024年第7期111-118,共8页Journal of Chinese Institute Of Food Science and Technology

基　　金：“十四五”国家重点研发计划重点专项(2021YFD2100402);黑龙江省自然联合引导基金项目(LH2022C044)。

摘　　要：通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)、圆二色谱、表面疏水性、荧光光谱以及分子对接等方法,研究不同热处理方式对大豆脂肪氧合酶(LOX)活力和构象的影响。结果表明:高温短时热处理可以显著降低LOX活力,其中120℃80 s+140℃15 s和100℃10 min热处理后,LOX活力分别降低了67.47%和60.53%。SDS-PAGE电泳结果显示高温热处理后LOX蛋白条带的分子质量并未发生明显变化,而条带强度减弱;热处理迫使LOX蛋白的α-螺旋和β-折叠相对含量降低,表面疏水性和内源性荧光强度增强,说明其二级结构和三级结构发生变化,LOX活力降低;通过分子对接模拟预测LOX活性中心非血红色铁周围的微环境,其在热处理过程中发生改变。推断高温热处理是通过破坏维持酶蛋白结构稳定的非共价相互作用力,促使LOX活性丧失,其中高温短时升温钝化LOX活性是较为合适的热处理方式。试验结果为大豆产品加工中LOX活性控制提供了数据参考。In this research,the effects of heating treatment conditions on LOX activity and conformation were studied by sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE),circular dichroism spectroscopy,surface hydrophobicity,fluorescence spectroscopy and molecular docking.The results showed that 120℃ 80 s+140℃ 15 s and 100℃ 10 min heating treatment could inhibit 67.47% and 60.53%of LOX activity.SDS-PAGE results showed that the molecular mass of the enzyme did not change significantly with heating conditions,but the band strength decreased.Moreover,heating treatment caused the decrease inα-helix and β-sheet,and increased in fluorescence intensity and surface hydrophobicity,suggesting that the greatly changed secondary and tertiary structures of LOX lead to a rapid decline in LOX activity.Molecular docking determined that the microenvironment surrounding the non heme iron at the ac tive center of LOX was susceptible to temperature changes.Therefore,it was speculated that high-temperature heating treatment may affect the LOX activity by destroying the non-covalent interaction force that maintains the structure of enzyme.High-temperature short-time elevated-temperature inactivation of LOX is an appropriate heating method.The findings could provide a theoretical reference for the widespread application of LOX activity control in soybean processing.

关 键 词：脂肪氧合酶 热处理 酶活力 构象 

分 类 号：TS201.25[轻工技术与工程—食品科学]