糖基化反应对鸡蛋清蛋白与低聚麦芽糖交联物活性和功能性的影响

Influence of Glycation on Biological Activity and Functional Properties of Egg White Protein-maltooligosaccharide Conjugation

摘要:

本文以鸡蛋清蛋白与低聚麦芽糖为原料，进行糖基化修饰反应，以接枝度和褐变程度等指标分析糖基化程度，并研究糖基化修饰反应对接枝产物生物活性和功能特性的影响。结果表明，湿热法加热2 h的反应产物接枝度最高，褐变程度较小，即反应产物大多是初级阶段末期或中间阶段产物。糖基化修饰反应提高了鸡蛋清蛋白的金属还原力和清除DPPH自由基的能力，同时还可增强其螯合亚铁离子的能力。功能特性分析表明，糖基化修饰反应可提高鸡蛋清蛋白的溶解度和热稳定性，而不影响其乳化稳定性和乳化活性。同时，体外模拟消化实验表明，糖基化修饰反应降低了鸡蛋清蛋白的消化性，这可能与其在大肠中被肠道微生物降解有一定的关联。上述分析表明，糖基化反应可作为一种有效的修饰方法提高蛋白质的功能特性和生物活性。

Abstract:

In this study, egg-white protein and maltooligosaccharides were used for non-enzymatic glycation. The extent of glycation was evaluated in terms of degree of browning and grafting. The results showed that the glycation products obtained after heating for 2 h by moist-heat method showed the highest grafting degree and the lowest browning degree. Reaction products were generated mainly at the end of the initial or intermediate stages. The non-enzymatic glycation reaction not only improved the metal reducing power and DPPH-scavenging capacity of egg-white protein but also enhanced its Fe2+-chelating ability. The analysis of functional characteristics indicated that non-enzymatic glycation enhanced the solubility and thermostability of egg white protein, but did not affect its emulsifying activity and emulsion stability. Meanwhile, in vitro digestion experiments showed that non-enzymatic glycation reduced the digestibility of egg-white protein, which might be due to degradation by intestinal microorganisms in the large intestine. The above results indicate that non-enzymatic glycation reaction provides an effective approach to significantly enhance functional and bioactive properties of proteins.