Chitosan oligosaccharides (COS) are a derivative of low molecular weight chitosan and are potent natural antimicrobial agents. The antimicrobial activity of COS against Aspergillus flavus and Aspergillus fumigatus was evaluated by minimum inhibitory concentration (MIC) and inhibition of mycelial growth. The MICs of COS against these two fungi were 31.2 and 15.6 mg/mL, respectively. COS treatment rendered fungal mycelia wrinkled and deformed with a fractured appearance. COS also increased cellular permeability leading to a significant leakage of cellular components indicating membrane damage. This compound also dose-dependently reduced chitin production and enhanced chitinase activity while enhancing the accumulation of reactive oxygen species (ROS). These characteristics suggested that COS has inhibitory effects against food spoilage fungi and acts on the cell wall and membrane and alters cellular metabolism. COS shows promise for food industry applications since it is non-toxic to higher organisms.

壳寡糖 (COS) 是低分子量壳聚糖的衍生物，是有效的天然抗菌剂。COS对黄曲霉和烟曲霉的抗菌活性通过最小抑制浓度（MIC）和菌丝体生长的抑制来评估。COS 对这两种真菌的 MIC 分别为 31.2 和 15.6 mg/mL。COS 处理使真菌菌丝体皱缩变形，外观断裂。COS 还增加了细胞通透性，导致细胞成分显着渗漏，表明膜受损。该化合物还剂量依赖性地减少几丁质的产生并增强几丁质酶的活性，同时增强活性氧 (ROS) 的积累。这些特征表明，COS对食物腐败真菌具有抑制作用，并作用于细胞壁和细胞膜，改变细胞代谢。COS 显示出在食品工业应用中的前景，因为它对高等生物无毒。