Li Jiayi, Mu Guangqing, Tuo Yanfeng
School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, China.
Dalian Probiotics Function Research Key Laboratory, Dalian Polytechnic University, Dalian 116034, China.
Foods. 2023 Apr 3;12(7):1516. doi: 10.3390/foods12071516.
Bacteria in planktonic and biofilm forms exhibit different phenotypic properties. In this study, the phenotypic traits and probiotic functions of Y42 in planktonic and biofilm forms were assessed. After 36 h of static culture, scanning electron microscopy and confocal laser scanning microscopy showed that the . Y42 bacterial cells contained interconnected adhesive matter on the surface, forming a ~18 μm layer of dense biofilms. The surface properties of . Y42 in biofilm form, including autoaggregation ability, hydrophobicity, acid-base charge, and adhesiveness, were all higher than those in the planktonic form. Biofilm . Y42 showed a higher tolerance to adverse environmental conditions and a higher survival rate, enzymatic activity, and integrity after vacuum lyophilization. And biofilm . Y42 had higher adhesion to human enterocyte HT-29 cell monolayers, inhibited the expressions of proinflammatory factors IL-6 and TNF-α, and promoted the expressions of the anti-inflammatory factor IL-10 and barrier proteins Claudin-1 and Occludin. In addition, . Y42 in biofilm form can inhibit the adhesion and invasion of ATCC 19115 to HT-29 cell monolayers and is more effective in relieving the inflammatory reactions and injuries of HT-29 cells caused by ATCC 19115. In conclusion, . Y42 in biofilm form exhibited better probiotic functions compared to that in planktonic form. This indicated that Y42 can form biofilms to enhance its probiotic functions, which provided a theoretical basis for better development and utilization of Y42.
浮游态和生物被膜态的细菌表现出不同的表型特性。在本研究中，评估了浮游态和生物被膜态Y42的表型特征和益生菌功能。经过36小时的静态培养，扫描电子显微镜和共聚焦激光扫描显微镜显示，Y42细菌细胞表面含有相互连接的粘性物质，形成了一层约18μm厚的致密生物被膜。生物被膜态Y42的表面特性，包括自聚集能力、疏水性、酸碱电荷和粘附性，均高于浮游态。生物被膜态Y42对不良环境条件具有更高的耐受性，真空冻干后的存活率、酶活性和完整性更高。并且生物被膜态Y42对人肠上皮细胞HT-29单层的粘附性更高，抑制促炎因子IL-6和TNF-α的表达，并促进抗炎因子IL-10以及屏障蛋白Claudin-1和Occludin的表达。此外，生物被膜态Y42可以抑制ATCC 19115对HT-29细胞单层的粘附和侵袭，并且在减轻由ATCC 19115引起的HT-29细胞的炎症反应和损伤方面更有效。总之，与浮游态相比，生物被膜态Y42表现出更好的益生菌功能。这表明Y42可以形成生物被膜以增强其益生菌功能，为Y42的更好开发和利用提供了理论依据。
