College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, PR China.
College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, PR China.
Int J Biol Macromol. 2024 Oct;277(Pt 2):134252. doi: 10.1016/j.ijbiomac.2024.134252. Epub 2024 Jul 30.
Protein-glutaminase (EC 3.5.1.44, PG) can significantly improve the functional properties of food proteins. However, the low yield of PG has limited industrial applications. Results showed that 0.02 % tea saponin could increase the PG yield by 18.93 %. The transcription level of the PG gene was significantly enhanced, which promoted the extracellular secretion of PG through an increase in membrane permeability. On this basis, PG was used to modify high-temperature soybean meal protein (HSMP) due to its poor properties. In this study, the deamidation degree (DD) of PG-modified HSMP was optimized to 58.61 % by the response surface method. HSMP with different DD was prepared and its physicochemical and functional properties were studied. After PG treatment, the intermolecular repulsive force of HSMP increased, the particle size distribution became uniform, and the solution system was more stable. In addition, the surface morphology of HSMP gradually became loose and porous. The solubility of HSMP significantly improved, reaching 11.34 times that of untreated HSMP at pH 5.00. Meanwhile, the emulsifying and foaming capacity of HSMP significantly improved, but the foaming stability was reduced.
谷氨酰胺酶（EC 3.5.1.44，PG）可以显著改善食品蛋白质的功能特性。然而，PG 的低产量限制了其在工业上的应用。结果表明，质量浓度为 0.02%的茶皂素可以使 PG 的产量提高 18.93%。PG 基因的转录水平显著增强，通过增加膜的通透性促进 PG 的细胞外分泌。在此基础上，由于高温豆粕蛋白（HSMP）性质较差，利用 PG 对其进行改性。本研究采用响应面法优化 PG 改性 HSMP 的脱酰胺度（DD）至 58.61%。制备了不同 DD 的 HSMP，并研究了其理化和功能特性。PG 处理后，HSMP 的分子间斥力增加，粒径分布均匀，溶液体系更加稳定。此外，HSMP 的表面形态逐渐变得疏松多孔。HSMP 的溶解度显著提高，在 pH 5.00 时达到未处理 HSMP 的 11.34 倍。同时，HSMP 的乳化和起泡能力显著提高，但起泡稳定性降低。
