Effect of Lactobacillus plantarum JX025073.1 on intestinal floraand blood lipid in mice / 预防医学

Objective @#To learn the regulatory effect of Lactobacillus plantarum JX025073.1 on intestinal flora and blood lipid in mice, so as to provide the basis for the nutritional intervention of probiotics in hyperlipidemia population.@*Methods @#Thirty male ICR mice were randomly divided into a control group, a model group and a intervention group. The mice in the control group were fed with basic diet, and in the other two groups were fed with high fat diet. The mice in the intervention group was given 0.4 mL of Lactobacillus plantarum JX025073.1 fermentation liquid by gavage every day, and in the other two groups were given 0.4 mL of normal saline. The body weight of mice, the mass of heart, liver, spleen and kidney organs were weighed, and the organ index was calculated. The contents of total cholesterol (TC), triacylglycerol/triglyceride ( TG ), low density lipoprotein cholesterol ( LDL-C ) in serum, TC, TG in liver and in feces were determined by biochemical analyzer. Bifidobacterium, Lactobacillus and Escherichia coli in feces were cultured and counted. @* Results @#After 42 days, compared with the control group, The mice in the model group had higher body weights, higher levels of TC, TG and LDL-C in serum, higher levels of TC, TG in liver and in feces, more Escherichia coli, less Bifidobacterium and less Lactobacillus ( P<0.05 ). Compared with the model group, the mice in the intervention group had lower body weight, lower levels of TC, TG and LDL-C in serum, lower levels of TC in liver, less Escherichia coli, higher levels of TC in feces, more Bifidobacterium and more Lactobacillus ( P<0.05 ). @*Conclusion @#Lactobacillus plantarum JX025073.1 can effectively regulate the blood lipid and intestinal flora of mice fed with high fat diet.

A metabolomics and proteomics study of the Lactobacillus plantarum in the grass carp fermentation.

BACKGROUND: Lactobacillus plantarum, a versatile lactic acid-fermenting bacterium, isolated from the traditional pickles in Ningbo of China, was chosen for grass carp fermentation, which could also improve the flavor of grass carp. We here explored the central metabolic pathways of L. plantarum by using metabolomic approach, and further proved the potential for metabolomics combined with proteomics approaches for the basic research on the changes of metabolites and the corresponding fermentation mechanism of L. plantarum fermentation. RESULTS: This study provides a cellular material footprinting of more than 77 metabolites and 27 proteins in L. plantarum during the grass carp fermentation. Compared to control group, cells displayed higher levels of proteins associated with glycolysis and nucleotide synthesis, whereas increased levels of serine, ornithine, aspartic acid, 2-piperidinecarboxylic acid, and fumarate, along with decreased levels of alanine, glycine, threonine, tryptophan, and lysine. CONCLUSIONS: Our results may provide a deeper understanding of L. plantarum fermentation mechanism based on metabolomics and proteomic analysis and facilitate future investigations into the characterization of L. plantarum during the grass carp fermentation.

Synthesis and in-vitro antimicrobial evaluation of a high-affinity iron chelator in combination with chloramphenicol.

OBJECTIVES: The objectives of this study were first to design and synthesize a hexadentate chelator with high iron(III) affinity and, second, to evaluate its antimicrobial activity in the presence and absence of chloramphenicol. METHODS: A hexadentate ligand was synthesized by conjugating a protected bidentate compound onto a tripodal structure. The pKa values and iron affinity of the chelator were determined by spectophotometric titration. Minimum inhibitory concentrations were determined by visual inspection of broth turbidity. The bactericidal rates were calculated by counting the colony numbers on a light board after incubation with and without an antimicrobial agent. KEY FINDINGS: A hexadentate 3-hydroxypyridin-4-one was found to possess a high affinity for iron(III), with a pFe value of 31.2 (negative logarithm of concentration of the free iron(III) in solution (when [Fe³âº](Total) = 10⁻6) M; [Ligand](Total) = 105 M; pH = 7.4). We found that this chelator had an appreciable inhibitory effect in vitro against the two bacterial strains Providencia stuartii and Staphylococcus aureus, particularly in the presence of chloramphenicol. CONCLUSIONS: A 3-hydroxypyridin-4-one hexadentate ligand has potential as an antimicrobial agent. Combination therapy with this iron chelator plus chloramphenicol has potential for the treatment of extracellular infections.

Synthesis, iron(III)-binding affinity and in vitro evaluation of 3-hydroxypyridin-4-one hexadentate ligands as potential antimicrobial agents.

Iron is a critical element for the survival of bacteria. We have designed and synthesized two novel 3-hydroxypyridin-4-one hexadentate ligands with high affinity for iron(III), which disrupt bacterial iron absorption. Biological studies demonstrate that these two chelators have significant inhibitory effect against both Gram-positive and Gram-negative bacteria, and therefore have potential as antimicrobial agents.

In vitro inhibition of bacterial growth by iron chelators.

The antimicrobial activity of the iron(III)-selective 3-hydroxypyridin-4-one chelators, CP251(1) and CP252(2), was evaluated in comparison with that of diethylenetriamine-penta acetic acid (3). CP251 was found to exhibit an inhibitory effect on the growth of both Gram-positive and Gram-negative bacteria. CP251 may find application in the treatment of external infections such as those associated with wounds.