Suranaree University of Technology-- Jirawat Yongsawatdigul研究团队在Food Control发表题目为“Antibacterial activity of enzymatic corn gluten meal hydrolysate and ability to inhibit Staphylococcus aureus in ultra-high temperature processed milk”研究论文（酶法玉米蛋白粉水解物的抑菌活性及对超高温加工乳中金黄色葡萄球菌的抑制能力）。摘要： 本研究的目的是确定分离的玉米蛋白粉 (CGM) 水解产物的抗菌特性和活性模式。胃蛋白酶水解的 CGM 经反相液相色谱分离后的 P1 组分表现出最强的抗菌活性，对金黄色葡萄球菌 ATCC29213 的最低抑菌浓度 (MIC) 为 1 mM，最低杀菌浓度 (MBC) 为 4 mM。P1抗菌活性动力学表明，在1×MIC和2×MIC浓度下8小时，P1具有抑菌作用，但在4×MIC浓度下具有杀菌作用。共聚焦激光扫描显微镜观察到，1×MIC和4×MIC浓度的P1组分在暴露8小时后破坏了金黄色葡萄球菌的膜完整性。扫描电子显微镜和透射电子显微镜表明，暴露于P1组分后，金黄色葡萄球菌的细胞表面受损，细胞质渗漏。同步辐射-傅立叶透射红外 (SR-FTIR) 微光谱法显示，在 1 × MIC 浓度下暴露于 P1 8 小时后，金黄色葡萄球菌细胞膜的核酸、蛋白质和脂肪酸组成发生了变化。P1 的抗菌活性在 pH 4.5–6.5 和温度 40–100 °C 范围内表现出稳定性。P1 在浓度高达 8 mM 时表现出相对较低的溶血活性。在对接种了金黄色葡萄球菌 ATCC29213 的商用超高温牛奶进行的挑战测试中，8 mM 浓度的 P1 组分抑制了金黄色葡萄球菌的生长。鉴定出 11 种新型亲水肽（6 种阳离子肽和 5 种阴离子肽），其中 EAGGGEDDKKKVE 肽表现出最强的抗菌活性。我们得出结论，胃蛋白酶水解的 CGM 肽部分显示出可用作控制食品中金黄色葡萄球菌的新型抗菌剂的潜力。研究结果：3.1. 肽的分离Fig. 1. (A) Chromatogram of corn gluten meal hydrolysate (CGMH) peptide fractionation. (B) Antibacterial activity assay of six peptide fractions of CGMH towards Staphylococcus aureus ATCC29213 and Escherichia coli TISTR780 at a concentration of 2 mM. (C) Antibacterial activity of 3 selected peptide fractions of CGMH against the test bacteria at 2 mM.3.3. 杀菌曲线Fig. 2. Bactericidal curve of the P1 fraction against Staphylococcus aureus ATCC29213 at various concentrations during 24 h incubation.3.4. CLSMFig. 3. Confocal laser scanning micrographs of S. aureus ATCC29213 exposed to the P1 fraction and stained with SYTO-9 and propidium iodide (PI).3.5. SEM 和 TEMFig. 4. Scanning electron micrographs of (A) control without peptide; (B) S. aureus exposed with the P1 at 1 × MIC (1 mM); and (C) 4 × MIC (4 mM). Scale bars represent 1 μm.Fig. 5. Transmission electron micrograph of (A) S. aureus ATCC29213 without the P1 peptides (control); (B) S. aureus exposed to the P1 peptides at 1 × MIC (1 mM) for 8 h; (C) at 4 × MIC (4 mM) for 8 h.3.6. SR-FTIRFig. 6. The original SR-FTIR spectra of S. aureus ATCC29213 cells in the absence and presence of the P1 peptides (1 × MIC) at 0 and 4 h (A); The secondary derivative spectra of S. aureus in the absence and presence of the P1 peptides (1 × MIC) at 0 and 4 h in the region of 3000-2800 cm−1 (B); and the region of 1800-900 cm−1 (C).Fig. 7. 3D-PCA plot (A), loading plots of PC-1 (B), PC-2 (C) and PC-3 (D) of spectra obtained from S. aureus cells in the absence and presence (1 × MIC) of the P1 fraction incubated for 0 and 4 h.3.7. P1的抗菌稳定性Fig. 8. Effect of temperatures (A) and pH values on antibacterial activity of the P1 peptides at 1 × MIC against S. aureus ATCC29231; controlT = no heat treatment; C-4.5, C-5.5, C-6.5 indicate phosphate buffer at pH 4.5, 5.5, and 6.5, respectively, without peptide.3.8. 溶血活性Fig. 9. The hemolytic activity of P1 peptides on human red blood cells3.9. 在牛奶中的应用Fig. 10. Antibacterial effect of the P1 peptides against the S. aureus growth inoculated in UHT milk at 37 °C for 24 h原文链接：https://doi.org/10.1016/j.foodcont.2024.110998
