Abstract:

Objective: To study the effect of carrot slurry fermented with Lactobacillus plantarum NCU116 on intestinal
mucosal immunity in immunosuppressed mice. Methods: Immunosuppressed mouse model was established by
intraperitoneal injection of cyclophosphamid. Forty mice were randomly divided into 5 groups: blank control group, model
control group, carrot slurry group, fermented carrot slurry group and sterilized fermented carrot slurry group. The mice were
administered with slurry fermented with Lactobacillus plantarum NCU116 and sterilized fermented carrot slurry at a dose of
10 mL/(kg·d) for 21 consecutive days. At 24 h after the last administration, the mice in each group were sacrificed. Thymus
and spleen indices were determined, the contents of IL-2, TNF-α, IL-10 and sIgA in small intestine were determined by
using quantitative sandwich enzyme-linked immunosorbent assay (ELISA) kits, small intestine morphology was observed
by hematoxylin-eosin (HE) stained section and immunofluorescence was used to assay IgA-secreting B cells. Results:
Compared to the model control, carrot slurry fermented with Lactobacillus plantarum NCU116 could significantly increase
thymus and spleen indices and the number of IgA-secreting B cells, enhance IL-2 and sIgA levels and improve the intestinal
morphological structure. But the concentrations of TNF-α and IL-10 were not significantly increased. Conclusion: Carrot
slurry fermented with Lactobacillus plantarum NCU116 can effectively antagonize cyclophosphamide-induced immune
suppression and ameliorate intestinal morphological damage in mice, enhance immune function and improve intestinal
morphology in immunosuppressed mice.

Key words: Lactobacillus plantarum NCU116, fermented carrot slurry, intestinal mucosal immunity