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Lactobacillus plantarum SP8, isolated from traditional Chinese pickle juice, was utilized for the production of exopolysaccharides (EPSs), but the EPS yield was low under normal MRS medium. The single factor experiment and response surface methodology were used to optimize the medium components and culture conditions and the optimal conditions for EPS production were successfully obtained. Results showed that the optimum condition was glucose 22 g/L, yeast extract 30 g/L, fermentation temperature 35.6 °C, fermentation time 22 h and the theoretical EPS yield was 282.494 mg/L. The results were similar to the actual yield, 280.105 mg/L. By optimizing the culture conditions, the yield of L. plantarum SP8 EPS was improved by nearly 19 times. In the gas chromatography analysis, it was found that L. plantarum SP8 EPS consisted of d-rhamnose, arabinose, galactose, and d-acetylglucosamine, but glucose was not included, which was quite different from the reported heteropolysaccharide component of Lactobacillus. Furthermore, the antioxidant activity of L. plantarum SP8 EPS was evaluated with the in vitro scavenging abilities on DPPH·, $${\text{O}}_{2}^{ - }$$ and ·OH. The in vitro antioxidant activity study indicated that L. plantarum SP8 EPS possessed certain antioxidant activity. All results demonstrated the potential of L. plantarum SP8 in the food and dairy industry.

The objective of this study was to evaluate the effects of a three-strain yogurt formulation in slow-transit constipation (STC) patients. Each individual in both treatment groups consumed 250 mL of the formulated yogurt daily for a week (7 days), and fecal samples were collected for gut microbiota and short-chain fatty acid (SCFA) analyses. A significant increase in the defection frequency (p<0.001) and bacterial diversity (p=0.027) at the 100% sequence homology level and a decrease in the concentrations of acetic acid (p=0.014), propionic acid (p=0.019), and butanoic acid (p=0.005) were observed after the STC patients consumed three-strain yogurt formulation. In addition, the consumption of the three-strain yogurt formulation significantly altered the composition of the intestinal bacteria in the STC patients. The relative abundances of 23 genera in the top dominating genera were altered significantly after the STC patients consumed the yogurt. In summary, the consumption of 250 mL day− the three-strain yogurt formulation described in this study can play a role in improving the symptoms of STC.

Intestinal bacteria are symbiotic microbiota within the human gut and are implicated in the occurrence and development of colorectal cancer (CRC). The current study investigated the changes in bacterial composition prior to and following surgery, as well as the differences in the bacterial community structure between cancer tissue and adjacent normal tissue. The diversity of the bacterial community and the composition of the bacteria were assessed. In addition, phylogenetic analysis and principle component analysis (PCA) were performed. The results revealed that cancer tissue and adjacent normal tissue exhibited similar bacterial compositions. However, a significant difference was identified in the composition of intestinal bacteria in stool samples collected from patients following surgery compared with stool samples collected prior to surgery. Each patient had their own unique intestinal bacterial community, likely due to a number of factors, including diet, genetic factors and health status. In addition, phylogenetic trees revealed that the most abundant operational taxonomic unit, 0001, was associated with Escherichia coli in all samples. Finally, PCA suggested that the bacterial community structure in all patient stools was similar following surgery. The current study provides information regarding the diversity of the intestinal bacterial community of patients with CRC and provides a basis for postoperative intestinal assessments.

Lactobacillus plantarum is an important probiotic and is mostly isolated from fermented foods. We sequenced the genome of L. plantarum strain 5-2, which was derived from fermented soybean isolated from Yunnan province, China. The strain was determined to contain 3114 genes. Fourteen complete insertion sequence (IS) elements were found in 5-2 chromosome. There were 24 DNA replication proteins and 76 DNA repair proteins in the 5-2 genome. Consistent with the classification of L. plantarum as a facultative heterofermentative lactobacillus, the 5-2 genome encodes key enzymes required for the EMP (Embden-Meyerhof-Parnas) and phosphoketolase (PK) pathways. Several components of the secretion machinery are found in the 5-2 genome, which was compared with L. plantarum ST-III, JDM1 and WCFS1. Most of the specific proteins in the four genomes appeared to be related to their prophage elements.

The gut microbiota is known to have a considerable impact on health; some types of organisms, including bifidobacteria and lactobacilli, are considered to be ‘good’ colonizing bacteria, while other species are potentially pathogenic. The initial colonization of a newborn infant affects his/her health in the future. Recently, research has indicated that the fetus may actually be colonized with bacteria during gestation. Accordingly, this study was conducted to assess the similarities in the bacterial species detected in the infant’s first feces with samples obtained from the mother’s placenta and vagina., BACKGROUND: The gut microbiota plays an important role in human health. It is essential to understand how the composition of the gut microbiota in neonates is established. OBJECTIVES: To investigate the nature of the microbial community in the first feces of newborn infants compared with the mothers’ placentae and vaginas. METHODS: One infant who was delivered via Cesarean section was compared with an infant who was delivered vaginally. Bar-coded pyro-sequencing of 16S ribosomal RNA genes was used to investigate the bacterial community composition and structure of each site. RESULTS: Neonatal feces of both infants had similar bacterial communities, and they were similar to the mother’s placenta regardless of the method of delivery. The vaginal bacterial community differed between the two mothers, but not different sites within the vagina. The bacteria in the neonatal feces and the mothers’ placentae demonstrated considerably higher diversity compared with the vaginas. The family Lactobacillaceae dominated in the vaginal samples, while the most abundant family in the fecal and placental samples was Micrococcineae. CONCLUSIONS: These results may provide new directions for the study of infant gut microbial formation.

Two hundred and fourteen endophytic fungi were isolated from 500 segments of aquatic/riparian plants Ottelia acuminata, Myriophyllum verticillatum, Equisetum arvense, Cardamine multijuga, and Impatiens chinensis. They were identified to 31 taxa in which Cladosporium, Fusarium, and Geotrichum were the dominant genera. Among all isolates, 169 (79%) were anamorphic fungi, 1 (0.5%) was an teleomorphic ascomycete and 44 (21%) were sterile mycelia. There were significant differences in the colonization frequency of endophytes between the five plant species (X∼2=51.128, P

Members of group III histidine kinases from different filamentous fungi were previously shown to mediate osmoregulation and resistance to dicarboximide, phenylpyrrole and, aromatic hydrocarbon fungicides. In this study, we report the disruption of the gene encoding group III histidine kinase, AlHK1, in the economically important plant pathogen Alternaria longipes. The AlHK1 gene disruption had pleiotropic effects on this fungus. Besides the expected osmosensitivity and fungicides resistance, AlHK1 participated in the spore production process. In addition, the ΔAlHK1 strains had stronger aggressive ability to infect their host plant than that of their parental strain, the wild-type strain C-00, suggested that AlHK1 was involved in the pathogenicity of A. longipes and performed in this function by a negative manner. This is the first report to our knowledge.

An extracellular 72-kDa xylanase from an Escherichia coli transformant that harbored pXED30 carrying xynE of Aeromonas caviae ME-1 was purified by extraction following SDS-PAGE to electrophoretic homogeneity. The analysis of N-terminal 10 amino acid residues (Gly-Ala-Arg-Ala-Gln-Ala-Ala-Ala-Asp-Val) revealed a 72-kDa product derived by the cleavage of Gly26-Gly27 at the N-terminal region of 110 kDa XynE. The 72-kDa xylanase from A. caviae ME-1 was found to have the same sequence as that of the N-terminal 10 amino acid residues. When OmpT-deficient E. coli mutants were used as hosts, the 72-kDa xylanase was detected in cell-free extracts, but not in the culture supernatant, suggesting that OmpT is not involved in the cleavage at the C-terminal region, but is involved in the secretion of 72-kDa xylanase to the culture medium.