Chinese Paocai is a traditional fermented food containing an abundance of beneficial microorganisms. In this study, the microorganisms in Szechwan Paocai were isolated and identified, and a strain of lactic acid bacteria (Lactobacillus plantarum CQPC10, LP-CQPC10) was found to exert an inhibitory effect on constipation. Microorganisms were isolated and identified via 16S rDNA. Activated carbon was used to induce constipation in a mouse model and the inhibitory effect of LP-CQPC10 on this induced constipation was investigated via both pathological sections and qPCR (quantitative polymerase chain reaction). A strain of Lactobacillus plantarum was identified and named LP-CQPC10. The obtained results showed that, as compared to the control group, LP-CQPC10 significantly inhibited the amount, weight, and water content of faeces. The defecation time of the first tarry stool was significantly shorter in LP-CQPC10 groups than in the control group. The activated carbon progradation rate was significantly higher when compared to the control group and the effectiveness was improved. LP-CQPC10 increased the serum levels of MTL (motilin), Gas (gastrin), ET (endothelin), AchE (acetylcholinesterase), SP (substance P), and VIP (vasoactive intestinal peptide), while decreasing the SS (somatostatin) level. Furthermore, it improved the GSH (glutathione) level and decreased the MPO (myeloperoxidase), MDA (malondialdehyde), and NO (nitric oxide) levels. The results of qPCR indicated that LP-CQPC10 significantly up-regulated the mRNA expression levels of c-Kit, SCF (stem cell factor), GDNF (glial cell-derived neurotrophic factor), eNOS (endothelial nitric oxide synthase), nNOS (neuronal nitric oxide synthase), and AQP3 (aquaporin-3), while down-regulating the expression levels of TRPV1 (transient receptor potential cation channel subfamily V member 1), iNOS (inducible nitric oxide synthase), and AQP9 (aquaporin-9). LP-CQPC10 showed a good inhibitory effect on experimentally induced constipation, and the obtained effectiveness is superior to that of Lactobacillus bulgaricus, indicating the better probiotic potential of this strain.

Background and objectives: Paocai (pickled cabbage), which is fermented by lactic acid bacteria, is a traditional Chinese food. The microorganisms of Paocai were isolated and identified, and the constipation inhibition effect of one of the isolated Lactobacillus was investigated. Materials and Methods: The 16S rDNA technology was used for microbial identification. A mouse constipation model was established using activated carbon. After intragastric administration of Lactobacillus (109 CFU/mL), the mice were dissected to prepare pathological sections of the small intestine. Serum indicators were detected using kits, and the expression of small intestine-related mRNAs was detected by qPCR assay. Results: One strain of Lactobacillus was identified and named Lactobacillus fermentum CQPC03 (LF-CQPC03). Body weight and activated carbon propulsion rate were all higher in mice intragastrically administered with LF-CQPC03 compared with the control group, while the time to the first black stool in treated mice was lower than that in the control group. Serum assays showed that gastrin (Gas), endothelin (ET), and acetylcholinesterase (AchE) levels were significantly higher in the LF-CQPC03-treated mice than in the control group, while somatostatin (SS) levels were significantly lower than in the control mice. Mouse small intestine tissue showed that c-Kit, stem cell factor (SCF), and glial cell-derived neurotrophic factor (GDNF) mRNA expression levels were significantly higher in the LF-CQPC03 treated mice than in control mice, while transient receptor potential cation channel subfamily V member 1 (TRPV1) and inducible nitric oxide synthase (iNOS) expression levels were significantly lower in the LF-CQPC03 treated mice than in control mice. Conclusions: There is a better effect with high-dose LF-CQPC03, compared to the lower dose (LF-CQPC03-L), showing good probiotic potential, as well as development and application value.