乳酸乳球菌的单菌包埋技术及在胃肠道环境中的性能评价  

Single-cell Encapsulation of Lactococcus lactis and Evaluation of Its Performancewithin the Gastrointestinal Environment

作　　者：万昊 谢安琪 冯蕾[1] Wan Hao;Xie Anqi;Feng Lei(State Key Laboratory of Food Science and Resources,Nanchang University,Nanchang 330029)

机构地区：[1]南昌大学食品科学与资源挖掘全国重点实验室,南昌330029

出　　处：《中国食品学报》2024年第4期1-8,共8页Journal of Chinese Institute Of Food Science and Technology

基　　金：国家自然科学基金项目(32101212,32372322);江西省自然科学基金项目(20224ACB215009,2023ACB205024)。

摘　　要：由于益生菌对消化系统的强酸和高浓度胆汁盐环境较为敏感,并且在肠道中定殖能力较低,因此开发新颖有效的益生菌包埋体系用于解决上述问题很有必要。本研究使用羧甲基化β-葡聚糖(m GN),通过金属-酚醛网络结构(Fe-TA)的桥联作用,将其黏附在乳酸乳球菌(LL)表面,构建乳酸乳球菌的包埋体系LL@Fe-TA@mGN,并评价LL@Fe-TA@mGN对胃液与胆盐的抗性及其在体内的滞留能力。结果表明:当mGN的质量浓度为0.12 mg/mL时,LL@Fe-TA@mGN体系的粒径和zeta-电位都达到峰值,表明该质量浓度为mGN包埋单个乳酸乳球菌的最佳质量浓度。在MRS液体培养基中,LL@FeTA@mGN的生长曲线与LL的生长曲线没有显著性差异,说明mGN的毒性可以忽略不计。在扫描电镜与透射电镜分析中均可清晰地看到一层“膜”完整地包覆在乳酸乳球菌表面。经2 h模拟胃液与胆盐的孵育,mGN包埋后的LL抗胃液能力与抗胆盐能力相比于未包埋的LL分别提升14.63倍与1.94倍。体内荧光成像实验证实LL@Fe-TA@mGN具有更强的肠道滞留能力。综上,本研究开发的乳酸乳球菌单菌包埋技术能够显著提升乳酸乳球菌的胃肠道抗性与体内滞留能力。研究结果可为益生菌包埋系统的开发与利用提供新的思路和策略。The development of novel and effective probiotic encapsulation systems is imperative in light of the susceptibility of probiotics to the acidic and highly-concentrated bile salts environment within the gastrointestinal tract.Carboxymethylatedβ-glucan(mGN)was utilized in this study to adhere to the surface of Lactococcus lactis(LL)through the bridging of a metal-phenolic network(Fe-TA),aiming to achieve the single-cell encapsulation of LL(LL@Fe-TA@mGN)and assess the gastrointestinal stress resistance and intestinal retention capacity of LL@[e-mail] results demonstrated that the particle size and zeta-potential of LL@Fe-TA@mGN reached maximum values when 0.12 mg/mL mGN was applied,indicating the full encapsulation of LL at the single-cell level.No significant difference was observed for the growth curve between LL@Fe-TA@mGN and LL in the MRS medium,ruling out the potential toxicity of mGN.Both SEM and TEM clearly revealed the presence of a distinct‘film’layer on the surface of LL,providing further evidence that LL was encapsulated within the mGN.With the protection of mGN,the survival rate of LL@Fe-TA@mGN could be up to 14.63 and 1.94 times higher than that of bare LL after exposure to simulated gastric fluid and bile salts for 2 h,respectively.In vivo fluorescence imaging corroborated the prolonged intestinal retention ability of LL@[e-mail] summary,the single-cell encapsulation strategy we developed here could significantly enhance gastrointestinal resistance and prolong the intestinal retention of LL.These results offer novel insights for the development and application of probiotic encapsulation systems.

关 键 词：羧甲基化β-葡聚糖 乳酸乳球菌 抗胃液 抗胆盐 体内滞留 

分 类 号：TS201.3[轻工技术与工程—食品科学]