The low viability during gastrointestinal transit and poor mucoadhesion considerably limits the effectiveness of Ligilactobacillus salivarius Li01 (Li01) in regulating gut microbiota and alleviating inflammatory bowel disease (IBD). In this study, a delivery system was designed through layer-by-layer (LbL) encapsulating a single Li01cell with chitosan and alginate. The layers were strengthened by cross-linking to form a firm and mucoadhesive shell (~10 nm thickness) covering the bacterial cell. The LbL Li01 displayed improved viability under simulated gastrointestinal conditions and mucoadhesive function. Almost no cells could be detected among the free Li01 after 2 h incubation in digestive fluids, while for LbL Li01, the total reduction was around 3 log CFU/mL and the viable number of cells remained above 6 log CFU/mL. Besides, a 5-fold increase in the value of rupture length and a two-fold increase in the number of peaks were found in the (bacteria-mucin) adhesion curves of LbL Li01, compared to those of free Li01. Oral administration with LbL Li01 on colitis mice facilitated intestinal barrier recovery and restoration of the gut microbiota. The improved functionality of Li01 by LbL encapsulation could increase the potential for the probiotic to be used in clinical applications to treat IBD; this should be explored in future studies.

胃肠道运输过程中的低活力和较差的粘膜粘附性极大地限制了唾液乳酸菌Li01 (Li01) 在调节肠道微生物群和减轻炎症性肠病 (IBD) 方面的有效性。在本研究中，通过用壳聚糖和海藻酸盐逐层（LbL）封装单个Li01细胞来设计递送系统。这些层通过交联得到强化，形成覆盖细菌细胞的坚固的粘膜粘附外壳（约 10 nm 厚）。 LbL Li01 在模拟胃肠道条件和粘膜粘附功能下表现出改善的活力。在消化液中孵育 2 小时后，游离 Li01 中几乎检测不到任何细胞，而对于 LbL Li01，总减少量约为 3 log CFU/mL，而活细胞数仍保持在 6 log CFU/mL 以上。此外，与游离 Li01 相比，LbL Li01 的（细菌-粘蛋白）粘附曲线的断裂长度值增加了 5 倍，峰数量增加了 2 倍。结肠炎小鼠口服 LbL Li01 可促进肠道屏障恢复和肠道微生物群的恢复。 LbL 封装改善了 Li01 的功能，可以增加益生菌在临床应用中治疗 IBD 的潜力；这应该在未来的研究中进行探讨。