Tryptophan is an essential amino acid for the human body, whose intake is through the diet. Several studies support the theory that microbiota­derived tryptophan metabolite played a crucial role in...

Lactobacillus acidophilus KDSL 1.0901，Lactobacillus helveticus KDSL 1.8701and Lactobacillus plantarum KDSL 1.0318 showed antibacterial activity, antioxidant activity and immunomodulatory activity. In the current study, we evaluated the effects of three tested...

The intestinal barrier is vital in preventing inflammatory bowel diseases (IBD). This study aimed to investigate the potential mechanism behind the protective effects of B. dentium N8 on the intestinal...

Bacillus cereus is an important food-borne pathogenic bacteria and a putrid microorganism in the dairy industry. Raw and pasteurized buffalo milk play important roles in the dairy market in southwestern China. However, the reports on the prevalence and characterization of B. cereus strains isolated from the above sources are lacking. In this study, 150 raw buffalo milk samples and 300 pasteurized buffalo milk samples were collected from 3 provinces in southwestern China. The genotype, virulence gene distribution, antibiotic resistance, and biofilm-forming ability of isolates were analyzed. Ninety-six B. cereus strains were isolated and identified: 50 isolates (33.3%) from buffalo raw milk and 46 isolates (15.3%) from pasteurized buffalo milk. These strains were classified into 41 sequence types (ST) and 5 groups, of which ST857 was the predominant ST. The detection rates of virulence genes nheABC cluster, hblACD cluster, cytK, bceT, entFM, hlyII, and cesB were 89.6%, 13.5%, 64.6%, 71.9%, 84.4%, 62.5%, and 6.25%, respectively. The antimicrobial susceptibility testing showed that more than 90% of the isolates were susceptible to gentamicin, chloramphenicol, ciprofloxacin, erythromycin, vancomycin, and tetracycline, as well as resistant to ampicillin, cefepime, oxacillin, and rifampin. The results of biomass biofilm evaluation of the isolates on the stainless-steel tube showed that the optical density values at a wavelength of 595 nm of all strains in group I were greater than 1, with the strongest overall biofilm-forming ability among 5 groups, and the overall biofilm-forming ability of group III was the weakest. There was a relationship between the biofilm-forming ability and phylogenetic relation-ship of B. cereus strains. Taken together, our findings are the first to report the contamination situation and characterization of B. cereus isolated from raw and pasteurized buffalo milk in southwestern China as well as indicate the potential risk posed by this pathogen to dairy industry and public health.

Studies on the possible alternative supplements to breastmilk are gaining research interests. Although milk from cow, goat, and mare is nutritious, its effects on the relationship between the immune system, metabolites, and gut microbiota remain unclear. This study aimed to comprehensively evaluate the effects of cow, goat, and mare milk on the immune system, metabolites, and gut microbiota of mice colonized by healthy infant feces using human milk as a standard. We examined the serum biochemistry parameters, immunity indicators, T cells, gut microbiota abundance, and metabolites. Results showed that the impact of human milk on alanine transaminase, glutamic oxaloacetic transaminase, total protein, globulin, and glucose values was different from the cow, goat, and mare milk types. The effects of mare milk on the percentage of CD4 + T, Th1, Th2, Th17, and Treg cells, and the levels of IL-2, IL-4, sIgA, and D-lactic acid in the serum of the human microbiota-associated mice were comparable to those of human milk. Also, bacterial 16S rRNA gene sequence analysis revealed that human milk enriched the relative abundance of Akkermansia and Bacteroides, cow milk increased the relative abundance of Lactobacillus, goat milk increased the relative abundance of Escherichia-Shigella, and mare milk improved the relative abundance of Klebsiella. Besides, mare milk was similar to human milk in the concentration of the metabolites we analyzed. Our findings suggest that mare milk can positively modulate the gut microbiota and immunity status of infants and thus could be a possible replacement for human milk.