Publications by authors named "Xinxi Gu"

American Oyster Defensin (AOD) is a marine peptide that is derived from North American mussels. It has been demonstrated to exhibit potent antimicrobial activity and high safety in both in vitro and in vivo models. In this study, to facilitate synthesis, mutants of AOD with fewer disulfide bonds were designed and subjected to structural, antimicrobial, and anti-biofilm analysis.

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The marine peptide, American oyster defensin (AOD), is derived from and exhibits a potent bactericidal effect. However, recombinant preparation has not been achieved due to the high charge and hydrophobicity. Although the traditional fusion tags such as Trx and SUMO shield the effects of target peptides on the host, their large molecular weight (12-20 kDa) leads to the yields lower than 20% of the fusion protein.

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Objectives: To produce nattokinase in a food-grade expression system and evaluate its thrombolytic activity in vitro.

Results: No nattokinase activity from reconstituted strains was observed in simulated gastric juice, but the enzyme was stable in intestinal fluid, the relative activity of which was found to be 60% after 4 h. Due to the nattokinase being produced intracellularly by recombinant bacterial strains, the persistence of the bacteria in gastric juice ensured transmission of the nattokinase into intestinal juice.

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Fermented milk is an effective carrier for probiotics, the consumption of which improves host health. The beneficial effects of probiotics, prebiotics, and synbiotics on gut dysbiosis have been reported previously. However, the way in which specific probiotics, prebiotics, and synbiotics regulate intestinal microbes remains unclear.

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The health-promoting effects of the probiotic strain Lactobacillus rhamnosus are based on its adherence and colonization ability. However, little is known about its adhesion and colonization rates. Lactobacillus rhamnosus in mouse intestinal mucosa a mutant of the red fluorescence protein (RFP) DSred2 was used to tag L.

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Aflatoxin M (AFM ) is a potent mycotoxin which causes serious health concerns in developing countries, where it is mainly found in milk, meat, and other foods. Biological detoxification is a promising method for eliminating AFM . The aim of this work was to search for AFM -degrading bacterial strains from animal waste, soil, and activated sludge.

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Lactobacillus plantarum KLDS1.0391 is a probiotic strain isolated from the traditional fermented dairy products and identified to produce bacteriocin against Gram-positive and Gram-negative bacteria. Previous studies showed that the strain has a high resistance to gastrointestinal stress and has a high adhesion ability to the intestinal epithelial cells (Caco-2).

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Ethnopharmacological Relevance: Many Chinese herbs are traditionally used as medicine to improve the functions of gastrointestinal tract. Some of these herbs are also promising agents for the improvement of the gut microbiota and the treatment of ulcerative colitis.

Materials And Methods: By screening seven traditional Chinese herbs, we found that Red Ginseng and Semen Coicis were the most effective in promoting the growth of probiotics including Lactobacillus and Bifidobacterium in vitro.

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The effects of the expression of a small heat shock protein (shsp) gene from Streptococcus thermophilus on stress resistance in Lactococcus lactis under different environmental stresses were investigated in this study. pMG36e-shsp, an expression vector, was first constructed by inserting a shsp open reading frame (ORF) cloned from S. thermophilus strain St-QC into pMG36e.

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