College of Food Science and Technology, Shanghai Ocean University, Shanghai, China.
College of Food Science and Technology, Shanghai Ocean University, Shanghai, China; Shanghai Aquatic Products Processing and Storage Engineering Technology Research Center, Shanghai, China; National Experimental Teaching Demonstration Center for Food Science and Engineering, Shanghai Ocean University, Shanghai, China.
Microb Pathog. 2022 Dec;173(Pt A):105748. doi: 10.1016/j.micpath.2022.105748. Epub 2022 Sep 5.
In this work, Chitosan-grafted-chlorogenic acid (CS-g-CA) was prepared by the carbodiimide method. The purpose of this study was to investigate the antibacterial and anti-biofilm activity of CS-g-CA against Staphylococcus aureus (S. aureus). The minimum inhibitory concentration (MIC) of CS-g-CA against S. aureus was identified as 0.625 mg/mL. S. aureus treated with 1/2 × MIC of CS-g-CA had a longer logarithmic growth phase than that of the CK group, while 1 × MIC and 2 × MIC inhibited the growth of bacteria. The damaging effect of CS-g-CA on bacterial cells was analyzed by measuring the activity of cellular antioxidant enzymes (Catalase (CAT) and Glutathione peroxidase (GSH-Px)) and intracellular enzymes (alkaline phosphatase (AKPase) and adenosine triphosphatase (ATPase)). The results of DNA gel electrophoresis illustrated that CS-g-CA disrupted the normal metabolism of bacteria. Scanning electron microscopy (SEM) results showed that S. aureus shrank and died under CS-g-CA treatment. 1 × MIC of CS-g-CA can significantly inhibit the formation of biofilms, and 1/2 × MIC of CS-g-CA control the swimming speed of S. aureus. In addition, 77.53% mature biofilm and 60.62% extracellular polysaccharide (EPS) in the mature biofilm of S. aureus were eradicated by CS-g-CA at 2 × MIC. Confocal laser scanning microscopy (CLSM) observation further confirmed these results. Therefore, CS-g-CA was an antimicrobial and antibiofilm agent to control S. aureus, which can effectively controlling the growth of S. aureus in food, thereby preventing the occurrence of food-borne diseases.
在这项工作中，通过碳二亚胺法制备了壳聚糖接枝绿原酸（CS-g-CA）。本研究旨在研究 CS-g-CA 对金黄色葡萄球菌（S. aureus）的抗菌和抗生物膜活性。CS-g-CA 对 S. aureus 的最小抑菌浓度（MIC）确定为 0.625mg/mL。用 1/2×MIC 的 CS-g-CA 处理的 S. aureus 的对数生长期比 CK 组长，而 1×MIC 和 2×MIC 抑制了细菌的生长。通过测量细胞抗氧化酶（过氧化氢酶（CAT）和谷胱甘肽过氧化物酶（GSH-Px））和细胞内酶（碱性磷酸酶（AKPase）和三磷酸腺苷酶（ATPase））的活性来分析 CS-g-CA 对细菌细胞的破坏作用。DNA 凝胶电泳结果表明，CS-g-CA 破坏了细菌的正常代谢。扫描电子显微镜（SEM）结果表明，S. aureus 在 CS-g-CA 处理下收缩和死亡。1×MIC 的 CS-g-CA 能显著抑制生物膜的形成，而 1/2×MIC 的 CS-g-CA 能控制 S. aureus 的游动速度。此外，2×MIC 的 CS-g-CA 可消除 S. aureus 成熟生物膜中 77.53%的成熟生物膜和 60.62%的胞外多糖（EPS）。共聚焦激光扫描显微镜（CLSM）观察进一步证实了这些结果。因此，CS-g-CA 是一种抗微生物和抗生物膜剂，可有效控制食品中 S. aureus 的生长，从而预防食源性疾病的发生。
