Molecular characterization of gut microbiome in weaning pigs supplemented with multi-strain probiotics using metagenomic, culturomic, and metabolomic approaches.

BACKGROUND: Probiotics have been reported to exhibit positive effects on host health, including improved intestinal barrier function, preventing pathogenic infection, and promoting nutrient digestion efficiency. These internal changes are reflected to the fecal microbiota composition and, bacterial metabolites production. In accordance, the application of probiotics has been broadened to industrial animals, including swine, which makes people to pursue better knowledge of the correlation between changes in the fecal microbiota and metabolites. Therefore, this study evaluated the effect of multi-strain probiotics (MSP) supplementation to piglets utilizing multiomics analytical approaches including metagenomics, culturomics, and metabolomics. RESULTS: Six-week-old piglets were supplemented with MSP composed of Lactobacillus isolated from the feces of healthy piglets. To examine the effect of MSP supplement, piglets of the same age were selected and divided into two groups; one with MSP supplement (MSP group) and the other one without MSP supplement (Control group). MSP feeding altered the composition of the fecal microbiota, as demonstrated by metagenomics analysis. The abundance of commensal Lactobacillus was increased by 2.39%, while Clostridium was decreased, which revealed the similar pattern to the culturomic approach. Next, we investigated the microbial metabolite profiles, specifically SCFAs using HPLC-MS/MS and others using GC-MS, respectively. MSP supplement elevated the abundance of amino acids, including valine, isoleucine and proline as well as the concentration of acetic acid. According to the correlation analyses, these alterations were found out to be crucial in energy synthesizing metabolism, such as branched-chain amino acid (BCAA) metabolism and coenzyme A biosynthesis. Furthermore, we isolated commensal Lactobacillus strains enriched by MSP supplement, and analyzed the metabolites and evaluated the functional improvement, related to tight junction from intestinal porcine enterocyte cell line (IPEC-J2). CONCLUSIONS: In conclusion, MSP administration to piglets altered their fecal microbiota, by enriching commensal Lactobacillus strains. This change contributed amino acid, acetic acid, and BCAA concentrations to be increased, and energy metabolism pathway was also increased at in vivo and in vitro. These changes produced by MSP supplement suggests the correlation between the various physiological energy metabolism functions induced by health-promoting Lactobacillus and the growth performance of piglets.

Ingestion of Gouda Cheese Ameliorates the Chronic Unpredictable Mild Stress in Mice.

Depression is a kind of mood disorder characterized by decline in motivation, interest, attention, mental activity, and appetite. Although depression is caused by a variety of causes, including genetic, endocrine and environmental stress, mild depression has been reported to improve with diet. Therefore, various type of food sources including functional and nutritional supplement are required to treat the depressive patients. Cheese contains bioactive peptides that have beneficial effects on host health. In particular, Jersey milk has been reported to contain higher solids than does Holstein milk. This study investigated the effects of Gouda cheese from Jersey and Holstein milk on chronic, unpredictable, mildly stressed (CUMS) mice. Here, spontaneous alterations in cheese-fed stressed mice were noted to be effectively recovered with statistical significance regardless cow species. Interestingly, for the analysis of fecal microbiota, Bacteroidetes were noted to increase with a reduction in Firmicutes at the phylum level with Jersey cheese. Taken together, we suggest that cheese intake provided a beneficial effect on stressed mice in recovering recognition ability. In particular, changes in internal microbiota were observed, suggesting that the bioactive ingredients in cheese act as improvement agents with respect to mood and brain function.

Simple Evaluation of Listeria monocytogenes Pathogenesis Using Caenorhabditis elegans Animal Model.

Listeria monocytogenes is a major cause of serious foodborne illness in the dairy foods. Although Caenorhabditis elegans model is well established as a virulence model of pathogenic bacteria, its application on L. monocytogenes is critically unclear. The objective of this study was to carry out an evaluation of L. monocytogenes toxicity using C. elegans nematode as a simple host model. We found that C. elegans nematodes have high susceptibility to L. monocytogenes infection, as a consequence of accumulation of bacteria in the worms' intestine. However, L. innocua, which is known to be non-toxic, is not accumulate in the intestine of worms and is not toxic similarly to Escherichia coli OP50 known as the normal feed source of C. elegans. Importantly, immune-associated genes of C. elegans were intensely upregulated more than 3.0-fold when they exposed to L. monocytogenes. In conclusion, we established that C. elegans is an effective model for studying the toxicity of L. monocytogenes and we anticipate that this system will result in the discovery of many potential anti-listeria agents for dairy foods.

Comparative Genome Analysis and Evaluation of Probiotic Characteristics of Lactobacillus plantarum Strain JDFM LP11.

In the current study, the probiotic potential of approximately 250 strains of lactic acid bacteria (LAB) isolated from piglet fecal samples were investigated; among them Lactobacillus plantarum strain JDFM LP11, which possesses significant probiotic potential, with enhanced acid/bile tolerance, attachment to porcine intestinal epithelial cells (IPEC-J2), and antimicrobial activity. The genetic characteristics of strain JDFM LP11 were explored by performing whole genome sequencing (WGS) using a PacBio system. The circular draft genome have a total length of 3,206,883 bp and a total of 3,021 coding sequences were identified. Phylogenetically, three genes, possibly related to survival and metabolic activity in the porcine host, were identified. These genes encode p60, lichenan permease IIC component, and protein TsgA, which are a putative endopeptidase, a component of the phosphotransferase system (PTS), and a major facilitator in the gut environment, respectively. Our findings suggest that understanding the functional and genetic characteristics of L. plantarum strain JDFM LP11, with its candidate genes for gut health, could provide new opportunities and insights into applications in the animal food and feed additive industries.

Diversity and Characteristics of the Meat Microbiological Community on Dry Aged Beef.

Beef was dry aged for 40-60 days under controlled environmental conditions in a refrigerated room with a relative humidity of 75%-80% and air-flow. To date, there is little information on the microbial diversity and characteristics of dry aged beef. In this study, we explored the effect of change in meat microorganisms on dry aged beef. Initially, the total bacteria and LAB were significantly increased for 50 days during all dry aging periods. There was an absence of representative foodborne pathogens as well as coliforms. Interestingly, fungi including yeast and mold that possess specific features were observed during the dry aging period. The 5.8S rRNA sequencing results showed that potentially harmful yeasts/molds (Candida sp., Cladosporium sp., Rhodotorula sp.) were present at the initial point of dry aging and they disappeared with increasing dry aging time. Interestingly, Penicillium camemberti and Debaryomyces hansenii used for cheese manufacturing were observed with an increase in the dry aging period. Taken together, our results showed that the change in microorganisms exerts an influence on the quality and safety of dry aged beef, and our study identified that fungi may play an important role in the palatability and flavor development of dry aged beef.