Characterization of the broad-spectrum antibacterial activity of bacteriocin-like inhibitory substance-producing probiotics isolated from fermented foods.

Antimicrobial peptides, such as bacteriocin, produced by probiotics have become a promising novel class of therapeutic agents for treating infectious diseases. Selected lactic acid bacteria (LAB) isolated from fermented foods with probiotic potential were evaluated for various tests, including exopolysaccharide production, antibiotic susceptibility, acid and bile tolerance, antibacterial activity, and cell adhesion and cytotoxicity to gastric cell lines. Six selected LAB strains maintained their high viability under gastrointestinal conditions, produced high exopolysaccharides, showed no or less cytotoxicity, and adhered successfully to gastric cells. Furthermore, three strains, Weissella confusa CYLB30, Lactiplantibacillus plantarum CYLB47, and Limosilactobacillus fermentum CYLB55, demonstrated a strong antibacterial effect against drug-resistant Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella enterica serovar Choleraesuis, Enterococcus faecium, and Staphylococcus aureus. Whole genome sequencing was performed on these three strains using the Nanopore platform; then, the results showed that all three strains did not harbor genes related to toxins, superantigens, and acquired antimicrobial resistance, in their genome. The bacteriocin gene cluster was found in CYLB47 genome, but not in CYLB30 and CYLB55 genomes. In SDS-PAGE, the extract of CYLB30 and CYLB47 bacteriocin-like inhibitory substance (BLIS) yielded a single band with a size of less than 10 kDa. These BLIS inhibited the growth and biofilm formation of drug-resistant P. aeruginosa and methicillin-resistant S. aureus (MRSA), causing membrane disruption and inhibiting adhesion ability to human skin HaCaT cells. Moreover, CYLB30 and CYLB47 BLIS rescued the larvae after being infected with P. aeruginosa and MRSA infections. In conclusion, CYLB30 and CYLB47 BLIS may be potential alternative treatment for multidrug-resistant bacteria infections.

Effects of Types of Horticultural Activity on the Physical and Mental State of Elderly Individuals.

This study aimed to evaluate the effect of types of horticultural activities among elderly individuals in a senior citizen learning camp. We arranged four horticultural activities: Grass Doll, Kokedama, Rocky Leaf Prints, and Herb Tasting and Smelling. Twenty-seven senior citizens (60 to 76 years) were recruited to participate. We assessed their physiological and mental state before and after the activities by measuring heart rate variability (HRV), pulse rate, blood pressure, salivary amylase activity (SAA), and Profile of Mood States (POMS). Results showed that SAA was significantly lower after the Rocky Leaf Prints, Herb Tasting and Smelling, and Kokedama. Pulse rate had a downward trend after the four horticultural activities. The ratio of low frequency (LF) over high frequency (HF) results showed that the Rocky Leaf Prints had a larger downward trend, followed by Herb Tasting and Smelling. POMS scores indicated significant improvement for Rocky Leaf Prints and Herb Tasting and Smelling. The types including artistic creation and food tasting were promising methods for psychological relaxation, stress reduction, and vigor enhancement for elderly persons. Findings showed that the impact of activities involving contact with plants was more significant in short-term activities. We hope this study can help plan the horticultural activities of the elderly in the future.

Salmonella enterica serotype typhimurium and S. Stanley differ in genomic evolutionary patterns and early immune responses in human THP-1 cell line and CD14+ monocytes.

Salmonella Typhimurium and S. Stanley are the most prevalent serogroup B serovars to infect humans in Taiwan. The aim was to determine possible factors to influence the prevalence between S. Typhimurium and S. Stanley. Genotypes were determined by pulsed field gel electrophoresis (PFGE) analysis and the intracellular survival, phagocytosis, reactive oxygen species (ROS) production of human monocyte THP-1 cell and tumor necrosis factor-α(TNF-α), interleukin-6 (IL-6), and IL-1ßexpression in peripheral blood CD14+ cells after infection were analyzed. 182 S. Stanley was clonal disseminated with main pulsotypes 2 from 2004 to 2007. Overall S. Typhimurium evolved more genotypes, while S. Stanley conserved in genotypes. Human blood CD14+ monocytes expressed TNF-α, IL-6 and IL-1ß differently among serovars and bacterial conditions (live vs. killed). Live S. Stanley and S. Typhimurium suppressed the TNF-α and IL-6 expression compared to killed bacteria. However, live S. Typhimurium stimulated more IL-1ß expression than the killed bacteria, but S. Stanley expressed similar IL-1ß levels in both conditions. Furthermore, S. Stanley and S. Typhimurium differed in intracellular survival in the THP-1 cells, an early decrease for S. Stanley, not for S. Typhimurium. Additionally, higher reactive oxygen species (ROS) production in THP-1 cells was found agsinst S. Stanley infection, not found in S. Typhimurium. However, some isolates of S. Stanley could recover from early loss to become more in the monocytes than S. Typhimurium. Difference in phagocytized number, intracellular survival, ROS production and IL-1ß expression may contribute to prevalence different between two serovars.

Salmonella Serovars and Vaccination Effect on the Immune Responses of Male and Female Layers.

Salmonella Enteritidis, S. Gallinarum and S. Pullorum are common serovars to infect poultry and cause diseases differently. The antibody production and cellular immune responses of male and female layers were evaluated before and after inoculation. Before inoculation, S. Gallinarum and S. Pullorum could survive and grow in 10% sera from 6-week-old layers, and S. Enteritidis and E. coli were completely eliminated. The weights of the male and female layers were increased the lowest by inoculation with S. Gallinarum, followed by S. Pullorum, and S. Enteritidis. Inoculation with S. Enteritidis, S. Gallinarum and S. Pullorum increased the antibody titer in the males depending on the serovars and maintained same higher antibody level in females. Furthermore, an increased anti-Salmonella IgG titer was associated with bactericidal ability and the level was reduced by serovars and complemente. Despite the vaccination and serovars, the male layers expressed more IgG2a than IgG1, indicating preferential activation of the Th1 pathway. The inoculation number affected the expression level of IFN-γ and IL-12 in the blood not in the secretion of the peripheral blood mononucleated cells (PBMCs) and more inoculations increased the expression of both cytokines. Inoculation increased more reactive oxygen species (ROS) production in polymorphonuclear (PMN) cells, not the PBMCs. ROS production was greater in cells from the males than from the females and greater in the cells treated with S. Enteritidis than S. Gallinarum and S. Pullorum. These three serovars and their vaccinations differed in sera killing and immune responses.

Emergence of Salmonella enterica serovar Potsdam as a major serovar in waterfowl hatcheries and chicken eggs.

Salmonellosis is a common food-borne illness in humans caused by Salmonella-contaminated poultry and their products. In hatcheries, 110 Salmonella isolates were identified, mostly from first enrichment, and few from delayed enrichment. The Salmonella prevalence in goose and duck hatcheries was higher when measured by four multiplex PCR methods than by traditional culture (73.8% vs. 44.35%, P < 0.05); 97.3% of 110 isolates were Salmonella Potsdam of serogroup C1 and other isolates were Salmonella Montevideo of C1 and Salmonella Albany of C2. Plasmid and pulsed field gel electrophoresis genetic analysis revealed that isolates from duck hatcheries were more diverse than those from goose hatcheries. In Salmonella Potsdam, host species-specific genotypes were observed in geese for genotypes 3, 4, and 5 and in ducks for genotypes 7, 8, and 9, suggesting that Salmonella Potsdam may evolve into goose- and duck-specific isolates. An examination of 1121 eggs found that only Salmonella Potsdam was identified in 1.8% (7/591) of eggs from chickens fed on the ground, not housed in cages, and in egg content (6/7) as well as eggshell membrane (1/7). In conclusion, Salmonella Potsdam may be a major Salmonella infection in waterfowl and chicken eggs.