School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang, Jiangsu 212013, China; Institute of Food Physical Processing, Jiangsu University, 301 Xuefu Road, Zhenjiang, Jiangsu 212013, China.
School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang, Jiangsu 212013, China; Institute of Food Physical Processing, Jiangsu University, 301 Xuefu Road, Zhenjiang, Jiangsu 212013, China.
Food Chem. 2022 Aug 1;384:132537. doi: 10.1016/j.foodchem.2022.132537. Epub 2022 Feb 23.
This study aimed to investigate the effect of thermosonicaion (TS) with different frequency modes on the horseradish peroxidase (HRP) inactivation from the aspects of ultrasound field and enzyme structural changes. The relationships between the activity and structural modification were also evaluated. A thermal-only treatment was performed to estimate the action of ultrasound in TS treatment. Compared to mono-frequency, especially the 33 kHz, TS with dual- and tri-frequency modes showed an intensive inactivation impact on HRP. Exogenous hydroxyl radical test showed the hydroxyl radical played a vital role in HRP inactivation. Changes in hematin group, tertiary and secondary structures were also confirmed, and the inactivation process followed an all-or-none model. Morphological images indicated the aggregation and deformation of HRP molecules during TS treatment, and roughness values were changed accordingly. Pearson correlation analysis implied that the structural destruction on the spatial conformation of HRP was strongly related to its activity.
本研究旨在从超声场和酶结构变化方面探讨不同频率模式的热声离子化（TS）对辣根过氧化物酶（HRP）失活的影响。还评估了活性与结构修饰之间的关系。仅进行热疗处理以估计超声在 TS 处理中的作用。与单频相比，尤其是 33 kHz，双频和三频 TS 对 HRP 具有更强的灭活作用。外源羟基自由基测试表明，羟基自由基在 HRP 失活中起重要作用。血红素基团、三级和二级结构的变化也得到了证实，失活过程遵循全或无模式。形态图像表明，在 TS 处理过程中 HRP 分子发生聚集和变形，粗糙度值也随之发生变化。Pearson 相关分析表明，HRP 空间构象的结构破坏与其活性密切相关。
