Nofima AS - Norwegian Institute of Food, Fisheries and Aquaculture Research, P.O. Box 210, Osloveien 1, NO-1431 Ås, Norway.
Analyst. 2017 Jul 24;142(15):2812-2818. doi: 10.1039/c7an00488e.
The potential of dry-film Fourier-transform infrared (FTIR) measurements as a monitoring tool for enzymatic hydrolysis of protein-based substrates is explored in this study. As a proof-of-concept, the enzymatic digestion of bovine serum albumin using Alcalase was monitored. To evaluate the analytical approach on complex substrates with industrial relevance, salmon- and chicken-based substrates were digested for 80 minutes using Alcalase and a total of 12 FTIR spectra were acquired during the course of the hydrolysis. The observed changes in the IR spectral features as a function of hydrolysis time were found to be in agreement with the breakdown of the amide backbone and formation of amino and carboxylate terminals. Some of the most consistent markers for hydrolysis time were the bands at 1516 cm (-NH) and ∼1400 cm (-COO). Moreover, principal component analysis (PCA) of the FTIR spectra was used to demonstrate the systematic relationship of the hydrolysis time with key variables (wavelengths) in the protein backbone region (800-1800 cm). Scores in the first principal component versus the hydrolysis time have been shown to provide an overview of the process dynamics related to protein structural changes. The herein presented results suggest that dry-film FTIR measurements have potential as a rapid tool for monitoring industrial protein hydrolysis processes.
本研究探讨了干膜傅里叶变换红外（FTIR）测量作为监测蛋白基底物酶解过程的工具的潜力。作为概念验证，使用碱性蛋白酶监测牛血清白蛋白的酶解过程。为了评估该分析方法在具有工业相关性的复杂底物上的适用性，使用碱性蛋白酶对鲑鱼和鸡肉基底物进行了 80 分钟的酶解，在此过程中共采集了 12 个 FTIR 光谱。随着水解时间的变化，IR 光谱特征的变化与酰胺主链的断裂和氨基和羧基末端的形成一致。水解时间的一些最一致的标记物是 1516cm-1（-NH）和约 1400cm-1（-COO）处的峰。此外，FTIR 光谱的主成分分析（PCA）用于证明水解时间与蛋白主链区域（800-1800cm）中关键变量（波长）之间的系统关系。第一主成分的得分与水解时间的关系提供了与蛋白结构变化相关的过程动力学的概述。本文的结果表明，干膜 FTIR 测量具有作为监测工业蛋白水解过程的快速工具的潜力。
