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Goat milk powder is a nutritious and easy-to-store product that is highly favored by consumers. However, the presence of contaminating bacteria and their metabolites may significantly affect the flavor, solubility, shelf life, and safety of the product. To comprehensively and accurately understand the sanitary conditions in the goat milk powder production process and potential threats from bacterial contamination, a combination of Pacific Biosciences single molecule real-time sequencing and droplet digital PCR was used to evaluate bacterial contamination in seven goat milk powder samples from three dairies. Ten phyla, 119 genera, and 249 bacterial species were identified. Bacillus, Paenibacillus, Lactococcus, and Cronobacter were the primary genera. Bacillus cereus, Lactococcus lactis, Alkaliphilus oremlandii, and Cronobacter sakazakii were the dominant species. With droplet digital PCR, 6.3 × 10 4 copies per g of Bacillus cereus and 1.0 × 10 4 copies per g of Cronobacter spp. were quantified, which may increase the risk of food spoilage and the probability of foodborne illness and should be monitored and controlled. This study offers a new approach for evaluating bacterial contamination in goat milk powder and supplies a reference for the assessment of food safety and control of potential risk, which will be of interest to the dairy industry.

Background: Traditional Chongqing radish paocai fermented with aged brine is considered to have the most intense flavor and authentic taste. Eight 'Yanzhi' (red, RRPB group) and 'Chunbulao' (white, WRPB) radish paocai brine samples were collected from Chongqing peasant households, and the diversity and community structures of bacteria present in these brines were determined using PacBio single-molecule real-time sequencing of their full-length 16S rRNA genes., Results: In total, 30 phyla, 218 genera, and 306 species were identified from the RRPB group, with 20 phyla, 261 genera, and 420 species present in the WRPB group. Obvious differences in bacterial profiles between the RRPB and WRPB groups were found, with the bacterial diversity of the WRPB group shown to be greater than that of the RRPB group. This study revealed several characteristics of the bacteria composition, including the predominance of heterofermentative lactic acid bacteria, the species diversity of genus Pseudomonas, and the presence of three opportunistic pathogenic species., Conclusion: This study provides detailed information on the bacterial diversity and community structure of Chongqing radish paocai brine samples, and suggests it may be necessary to analyze paocai brine for potential sources of bacterial contamination and take appropriate measures to exclude any pathogenic species. © 2018 Society of Chemical Industry., (© 2018 Society of Chemical Industry.)

Background: In Kazakhstan, traditional artisanal cheeses have a long history and are widely consumed. The unique characteristics of local artisanal cheeses are almost completely preserved. However, their microbial communities have rarely been reported. The current study firstly generated the Single Molecule, Real-Time (SMRT) sequencing bacterial diversity profiles of 6 traditional artisanal cheese samples of Kazakhstan origin, followed by comparatively analyzed the microbiota composition between the current dataset and those from cheeses originated from Belgium, Russian Republic of Kalmykia (Kalmykia) and Italy., Results: Across the Kazakhstan cheese samples, a total of 238 bacterial species belonging to 14 phyla and 140 genera were identified. Lactococcus lactis (28.93%), Lactobacillus helveticus (26.43%), Streptococcus thermophilus (12.18%) and Lactobacillus delbrueckii (12.15%) were the dominant bacterial species for these samples. To further evaluate the cheese bacterial diversity of Kazakhstan cheeses in comparison with those from other geographic origins, 16S rRNA datasets of 36 artisanal cheeses from Belgium, Russian Republic of Kalmykia (Kalmykia) and Italy were retrieved from public databases. The cheese bacterial microbiota communities were largely different across sample origins. By principal coordinate analysis (PCoA) and multivariate analysis of variance (MANOVA), the structure of the Kazakhstan artisanal cheese samples was found to be different from those of the other geographic origins. Furthermore, the redundancy analysis (RDA) identified 16 bacterial OTUs as the key variables responsible for such microbiota structural difference., Conclusion: Our results together suggest that the diversity of bacterial communities in different groups is stratified by geographic region. This study does not only provide novel information on the bacterial microbiota of traditional artisanal cheese of Kazakhstan at species level, but also interesting insights into the bacterial diversity of artisanal cheeses of various geographical origins.

Infant formula (IF) requires a strict microbiological standard because of the high vulnerability of infants to foodborne diseases. The current study used the PacBio single-molecule real-time (SMRT) sequencing platform to generate full-length 16S rRNA-based bacterial microbiota profiles of 30 Chinese domestic and imported IF samples. A total of 600 species were identified, dominated by Streptococcus thermophilus, Lactococcus lactis, and Lactococcus piscium. Distinctive bacterial profiles were observed between the two sample groups, as confirmed with both principal coordinate analysis and multivariate analysis of variance. Moreover, the product whey protein nitrogen index (WPNI), representing the degree of preheating, negatively correlated with the relative abundances of the Bacillus genus. This study has demonstrated the application of the PacBio SMRT sequencing platform in assessing the bacterial contamination of IF products, which is of interest to the dairy industry for effective monitoring of microbial quality and safety during production.

SPLUNC1 is a multifunctional protein of the airway with antimicrobial properties. We previously reported that it displayed antibiofilm activities against P. aeruginosa. The goal of this study was to determine whether (1) the antibiofilm property is broad (including S. aureus, another prevalent organism in cystic fibrosis); (2) the α4 region is responsible for such activity; and (3), if so, this motif could be structurally optimized as an antimicrobial peptide with enhanced activities. We used S. aureus biofilm-prevention assays to determine bacterial biomass in the presence of SPLUNC1 and SPLUNC1Δα4 recombinant proteins, or SPLUNC1-derived peptides (α4 and α4M1), using the well-established crystal-violet biofilm detection assay. The SPLUNC1Δα4 showed markedly reduced biofilm prevention compared to the parent protein. Surprisingly, the 30-residue long α4 motif alone demonstrated minimal biofilm prevention activities. However, structural optimization of the α4 motif resulted in a modified peptide (α4M1) with significantly enhanced antibiofilm properties against methicillin–sensitive (MSSA) and–resistant (MRSA) S. aureus, including six different clinical strains of MRSA and the well-known USA300. Hemolytic activity was undetectable at up to 100μM for the peptides. The data warrant further investigation of α4-derived AMPs to explore the potential application of antimicrobial peptides to combat bacterial biofilm-related infections. [ABSTRACT FROM AUTHOR]