Dry Nutrition Delivery System Based on Defatted Soybean Particles and Its Application with ß-Carotene.

Many nutrition delivery systems (NDSs) have been developed for the encapsulation, protection, and delivery of bioactive compounds, such as ß-carotene. Most of those systems were prepared in solution, which is inconvenient for transportation and storage in the food industry. In the present work, we constructed an environmentally friendly dry NDS based on defatted soybean particles (DSPs) by milling a ß-carotene-DSP mixture. The loading efficiency of the NDS reached 89.0%, and the cumulative release rate decreased from 15.1% (free ß-carotene) to 6.0% within 8 h. The stability of ß-carotene in the dry NDS was found to have increased in a thermogravimetric analysis. Stored for 14 days at 55 °C or under UV irradiation, the retaining rates of ß-carotene in the NDS increased to 50.7% and 63.6%, respectively, while they were 24.2% and 54.6% for the free samples. The bioavailability of ß-carotene was improved by the NDS too. The apparent permeability coefficient of the NDS reached 1.37 × 10-6 cm/s, which is 12 times that of free ß-carotene (0.11 × 10-6 cm/s). Besides being environmentally friendly, the dry NDS can facilitate carriage, transportation, or storage in the food industry, and similar to other NDSs, it improves the stability and bioavailability of nutrients.

Effect of Bifidobacterium animalis subsp. lactis SF on enhancing the tumor suppression of irinotecan by regulating the intestinal flora.

The gut microbiota plays a role in tumor therapy by participating in immune regulation. Here, we demonstrated through 8-day probiotic supplementation experiments and fecal microbiota transplantation experiments that Bifidobacterium animalis subsp. lactis SF enhanced the antitumor effect of irinotecan and prevented the occurrence of intestinal damage by modulating the gut microbiota and reducing the relative abundance of pro-inflammatory microbiota. Therefore, the intestinal inflammation was inhibited, the TGF-ß leakage was reduced, and the PI3K/AKT pathway activation was inhibited. Thus, the tumor apoptotic autophagy was finally promoted. Simultaneously, the reduction of TGF-ß relieved the immunosuppression caused by CPT-11, promoted the differentiation of CD4+ and CD8+ T cells in tumor tissue, and consequently inhibited tumor growth and invasion. This study disclosed the mechanism of B. lactis SF assisting CPT-11 in antitumor activity and suggested that B. lactis SF plays a new role in anticancer effects as a nutritional intervention.

Whole genome and acid stress comparative transcriptome analysis of Lactiplantibacillus plantarum ZDY2013.

Previous study has reported that Lactiplantibacillus plantarum ZDY2013 which was screened from traditional Chinese fermented soybeans has a strong acid resistance. The purpose of this study was to uncover the genes potentially related to its genetic adaptation and probiotic profiles, based on comparative genomic and comparative transcriptome analysis. We got the basic information about L. plantarum ZDY2013 and identified genes which are related to genetic adaptation and probiotic profiles, including carbohydrate transport and metabolism, cell wall/membrane/envelope biogenesis, proteolytic enzyme systems and amino acid biosynthesis, CRISPR adaptive immunity, stress responses, ability to adhere to the host intestinal wall, exopolysaccharide (EPS) biosynthesis, and bacteriocin biosynthesis. Comparative transcriptome showed CK group (normal MRS culture L. plantarum ZDY2013) and SCL group (pH 3.0 MRS culture L. plantarum ZDY2013) had 652 significant differentially expressed genes including 310 up-regulated genes and 342 down-regulated genes. Besides that, these genes had been classified through KEGG and GO functional annotation. In addition, we also found top 20 KEGG pathways adjusted to acid stress. Then, some genes were selected to verify the transcriptome analysis and explore the mechanism of how L. plantarum ZDY2013 tolerate acid stress. We found that some genes of ABC transporter, phosphotransferase system, oxidation reduction process, membrane transporter and phosphorylation metabolism process had a significant change. These results suggested that comparative characterization of the L. plantarum ZDY2013 genome and transcriptome provided the genetic basis for further elucidating the functional mechanisms of it.

Effect of 3 lactobacilli on immunoregulation and intestinal microbiota in a ß-lactoglobulin-induced allergic mouse model.

Milk is one of the earliest and most common allergen sources in the world, with ß-lactoglobulin representing a major allergen protein. Numerous studies have reported that probiotics exert antiallergic and anti-inflammatory effects. Here, we examined the effects of 3 strains of Lactobacillus on immunomodulatory functions, intestinal barrier functions, and intestinal microbiota through a ß-lactoglobulin-induced allergic mouse model. We found that the oral administration of Lactobacillus plantarum ZDY2013 and Lactobacillus rhamnosus GG suppressed allergic response, attenuating serum IgE and relieving anaphylaxis symptoms. The 3 strains of Lactobacillus could induce T helper (Th) 1 or T regulatory cells to differentiate to inhibit the Th2-biased response for regulating Th1/Th2 immune balance. Furthermore, L. plantarum ZDY2013 and L. rhamnosus GG enhanced intestinal barrier function through the regulation of tight junction. We also found that L. plantarum ZDY2013 and L. plantarum WLPL04 could regulate alterations in intestinal microbiota caused by allergies. In particular, Rikenella, Ruminiclostridium, and Lachnospiraceae UCG-006 were considerably reduced after treatment with L. plantarum ZDY2013 and L. plantarum WLPL04. These results suggested that 3 Lactobacillus strains may serve as an effective tool for the treatment of food allergies by regulating immune and gut microbiota.

Potential of Lactobacillus plantarum ZDY2013 and Bifidobacterium bifidum WBIN03 in relieving colitis by gut microbiota, immune, and anti-oxidative stress.

Ulcerative colitis (UC) is an inflammatory bowel disease that is difficult to cure, with rising incidence in recent decades. Probiotics have become a new strategy for UC treatment. In this study, we chose 2 new multisource probiotics, Lactobacillus plantarum ZDY2013 from acid beans and Bifidobacterium bifidum WBIN03 from infant feces, and a mixture of both, to investigate the anti-inflammatory and antioxidant effect on H2O2-induced oxidative damage in a HT-29 cell model and dextran sodium sulfate (DSS)-induced UC in mice. Compared with the model group, the general relative indices results showed L. plantarum ZDY2013 and B. bifidum WBIN03 have a significant effect on DSS-induced UC in mice, by downregulating the pro-inflammatory cytokines (e.g., TNF-α) and upregulating antioxidant factors (e.g., SOD1, SOD2, GPX2) at the transcriptional level. By means of high-throughput sequencing (16S V3-V4) and systematical bioinformatics analyses, we found that colitis may be associated with the changes in intestinal flora, especially Firmicutes and Bacteroides. Administration of L. plantarum ZDY2013 increased the abundance of Lactobacillus animalis, whereas B. bifidum WBIN03 increased the abundance of Lachnospiraceae bacterium COE1. Our results revealed that a supplement of L. plantarum ZDY2013 and B. bifidum WBIN03 remit UC through modification of gut microbiota to regulate oxidative stress and inflammatory mediators.

Physiological and transcriptional responses and cross protection of Lactobacillus plantarum ZDY2013 under acid stress.

Acid tolerance responses (ATR) in Lactobacillus plantarum ZDY2013 were investigated at physiological and molecular levels. A comparison of composition of cell membrane fatty acids (CMFA) between acid-challenged and unchallenged cells showed that acid adaptation evoked a significantly higher percentage of saturated fatty acids and cyclopropane fatty acids in acid-challenged than in unchallenged cells. In addition, reverse transcription-quantitative PCR analysis in acid-adapted cells at different pH values (ranging from 3.0 to 4.0) indicated that several genes were differently regulated, including those related to proton pumps, amino acid metabolism, sugar metabolism, and class I and class III stress response pathways. Expression of genes involved in fatty acid synthesis and production of alkali was significantly upregulated. Upon exposure to pH 4.5 for 2 h, a higher survival rate (higher viable cell count) of Lactobacillus plantarum ZDY2013 was achieved following an additional challenge to 40 mM hydrogen peroxide for 60 min, but no difference in survival rate of cells was found with further challenge to heat, ethanol, or salt. Therefore, we concluded that the physiological and metabolic changes of acid-treated cells of Lactobacillus plantarum ZDY2013 help the cells resist damage caused by acid, and further initiated global response signals to bring the whole cell into a state of defense to other stress factors, especially hydrogen peroxide.

Changes in gastric microbiota induced by Helicobacter pylori infection and preventive effects of Lactobacillus plantarum ZDY 2013 against such infection.

Helicobacter pylori is a gram-negative pathogen linked to gastric ulcers and stomach cancer. Gastric microbiota might play an essential role in the pathogenesis of these stomach diseases. In this study, we investigated the preventive effect of a probiotic candidate Lactobacillus plantarum ZDY 2013 as a protective agent against the gastric mucosal inflammation and alteration of gastric microbiota induced by H. pylori infection in a mouse model. Prior to infection, mice were pretreated with or without 400 µL of L. plantarum ZDY 2013 at a concentration of 10(9) cfu/mL per mouse. At 6 wk postinfection, gastric mucosal immune response and alteration in gastric microbiota mice were examined by quantitative real-time PCR and high-throughput 16S rRNA gene amplicon sequencing, respectively. The results showed that L. plantarum ZDY 2013 pretreatment prevented increase in inflammatory cytokines (e.g., IL-1ß and IFN-γ) and inflammatory cell infiltration in gastric lamina propria induced by H. pylori infection. Weighted UniFrac principal coordinate analysis showed that L. plantarum ZDY 2013 pretreatment prevented the alteration in gastric microbiota post-H. pylori infection. Linear discriminant analysis coupled with effect size identified 22 bacterial taxa (e.g., Pasteurellaceae, Erysipelotrichaceae, Halomonadaceae, Helicobacteraceae, and Spirochaetaceae) that overgrew in the gastric microbiota of H. pylori-infected mice, and most of them belonged to the Proteobacteria phylum. Lactobacillus plantarum ZDY 2013 pretreatment prevented this alteration; only 6 taxa (e.g., Lachnospiraceae, Ruminococcaceae, and Clostridiaceae), mainly from the taxa of Firmicutes and Bacteroidetes, were dominant in the gastric microbiota of the L. plantarum ZDY 2013 pretreated mice. Administration of L. plantarum ZDY 2013 for 3 wk led to increase in several bacterial taxa (e.g., Rikenella, Staphylococcus, Bifidobacterium), although a nonsignificant alteration was found in the gastric microbiota. Overall, this study demonstrated that L. plantarum ZDY 2013 pretreatment played an important role in preventing gastric mucosal inflammation and gastric microbiota alteration induced by H. pylori infection, and the selective modulation in gastric microbiota posed by this intervention suggested that targeting gastric microbiota through oral administration of probiotics might be an alternative strategy to prevent H. pylori infection.

Evaluation of probiotic properties of Lactobacillus plantarum WLPL04 isolated from human breast milk.

Lactobacillus plantarum WLPL04, a specific strain isolated from human breast milk, was investigated for its survival capacity (acid and bile salt tolerance, survival in simulated gastrointestinal tract, inhibition of pathogens, antibiotic susceptibility, yield of exopolysaccharides) and probiotic properties (antiadhesion of pathogens, protection from harmful effect of sodium dodecyl sulfate, and antiinflammatory stress on Caco-2 cells). The results showed that Lb. plantarum WLPL04 had broad-spectrum activity against gram-positive strains (Listeria monocytogenes CMCC54007, Bacillus cereus ATCC14579, and Staphylococcus aureus CMCC26003) and gram-negative strains (Pseudomonas aeruginosa MCC10104, Shigella sonnei ATCC25931, Enterobacter sakazakii ATCC29544, Salmonella typhimurium ATCC13311, and Escherichia coli O157:H7). Antibiotic susceptibility tests showed that Lb. plantarum WLPL04 was susceptible to 8 of 14 antibiotics (e.g., erythromycin and nitrofurantoin) and resistant to 6 of 14 antibiotics (e.g., kanamycin and bacitracin). Lactobacillus plantarum WLPL04 was able to survive at pH 2.5 for 3h and at 0.45% bile salt for 12h, suggesting that it can survive well in the gastrointestinal tract. In addition, the exopolysaccharide yield of Lb. plantarum WLPL04 reached 426.73 ± 65.56 mg/L at 24h. With strategies of competition, inhibition, and displacement, Lb. plantarum WLPL04 reduced the adhesion of E. coli O157:H7 (35.51%), Sal. typhimurium ATCC 13311 (8.10%), and Staph. aureus CMCC 26003 (40.30%) on Caco-2 cells by competition, and subsequently by 59.80, 62.50, and 42.60%, respectively, for the 3 pathogens through inhibition, and by 75.23, 39.97, and 52.88%, respectively, through displacement. Lactobacillus plantarum WLPL04 attenuated the acute stress induced by sodium dodecyl sulfate on Caco-2 cells and significantly inhibited the expression of inflammatory cytokines (IL-6, IL-8 and tumor necrosis factor-α) on Caco-2 cells but increased IL-10 expression in vitro compared with the Salmonella-treated group. In summary, Lb. plantarum WLPL04 from breast milk could be considered as a probiotic candidate for dairy products to promote human health.

Screening probiotic strains for safety: Evaluation of virulence and antimicrobial susceptibility of enterococci from healthy Chinese infants.

The aim of this study was to evaluate the safety of enterococci isolated from Chinese infants and screen out potential probiotic candidates. One hundred eight strains were isolated from feces of 34 healthy infants, and 38 strains of Enterococcus spp. were categorized as follows: E. faecalis (22), E. faecium (10), E. hirae (3), E. durans (2), and E. casseliflavus (1). Of these, 72.7% of E. faecalis came from infants delivered by cesarean and 62.5% of E. faecium from infants delivered vaginally. For safety evaluation of strains, we determined presence of virulence genes; production of hemolysin, gelatinase, and biofilm; and antimicrobial susceptibility of enterococci. Six out of 14 virulence genes were detected with a distribution of gelE (26.3%), cylA (39.4%), esp (15.8%), efaA (63.2%), asa1 (50.0%), and ace (50.0%). In phenotype analysis, 36.8% of the strains exhibited positive hemolytic activity and 17.5% were positive for production of gelatinase. Results of antimicrobial susceptibility showed that different percentages of the strains were resistant to ciprofloxacin (5.2%), vancomycin (7.8%), rifampicin (10.5%), erythromycin (52.6%), and gentamycin (52.6%); remarkably, none of the strains were resistant to ampicillin or chloramphenicol. In total, 10 strains, including 6 E. faecium, which are free of virulence determinants and sensitive to common antimicrobial agents (e.g., ampicillin and vancomycin), were further assessed for their probiotic properties. All strains survived well in simulated gastric fluid and intestinal tract, with maximum reductions of 0.600 and 0.887 log cfu/mL, respectively. Six strains of E. faecium could resist 0.3 to 1.0% bile salt, of which E. faecium WEFA23 presented the highest growth (75.06%) at 1.0% bile salt. All strains showed bile salt hydrolase activity on glycodeoxycholic acid, but only 3 of E. faecium showed activity on taurodeoxycholic acid. These results deliver useful information on the safety of enterococci in infants in China, and provide a protocol to screen probiotics for absence of virulence and antimicrobial susceptibility of enterococci.

Short communication: Modulation of the small intestinal microbial community composition over short-term or long-term administration with Lactobacillus plantarum ZDY2013.

The small intestinal (SI) microbiota has an essential role in the maintenance of human health. However, data about the indigenous bacteria in SI as affected by probiotics are limited. In our study, the short-term and long-term effects of a probiotic candidate, Lactobacillus plantarum ZDY2013, on the SI microbiota of C57BL/6J mice were investigated by the Illumina HiSeq (Novogene Bioinformatics Technology Co., Ltd., Tianjin, China) platform targeting the V4 region of the 16S rDNA. A total of 858,011 sequences in 15 samples were read. The α diversity analysis revealed that oral administration with L. plantarum ZDY2013 for 3 wk led to a significant increase in the richness and diversity of the SI bacterial community. Principal coordinate analysis and unweighted pair-group method with arithmetic means analysis showed a clear alteration in the SI microbiota composition after 3 wk of L. plantarum ZDY2013 treatment, although these changes were not found 6 wk after ceasing L. plantarum ZDY2013 administration. Species annotation showed that the dominant phyla in SI microbiota were Firmicutes, Bacteroidetes, Proteobacteria, and Verrucomicrobia. Interestingly, operational taxonomic unit cluster analysis showed that administration with L. plantarum ZDY2013 for 3 wk significantly increased the abundance of Proteobacteria, but decreased that of Bacteroidetes. Linear discriminant analysis coupled with effect size identified 18 bacterial taxa (e.g., Ruminococcus spp. and Clostridium spp.) that overgrew in the SI microbiota of the mice administered with L. plantarum ZDY2013 for 3 wk, and most of them belonged to the phyla Bacteroidetes and Proteobacteria. However, only one bacterial taxon (e.g., Nocardioides spp.) was over-represented in the SI microbiota of mice 6 wk after L. plantarum ZDY2013 administration. Overall, this study shows that oral administration with probiotic results in an important but transient alteration in the microbiota of SI.

In vitro probiotic characteristics of Lactobacillus plantarum ZDY 2013 and its modulatory effect on gut microbiota of mice.

Lactobacillus plantarum ZDY 2013, a novel strain isolated from Chinese traditional fermented acid beans, was systematically evaluated for its survival capacity under stress conditions (pH, bile salt, simulated gastrointestinal tract, and antibiotics), production of exopolysaccharide and antagonism against 8 pathogens. Its effect on mice gut microbiota was also investigated by quantitative PCR and PCR-denaturing gradient gel electrophoresis. The results showed that ZDY 2013 can grow at pH 3.5 and survive at pH 2.0 for 6 h and at 0.45% bile salt for 3 h. The exopolysaccharide yield was up to 204±7.68 mg/L. The survival rate of ZDY 2013 in a simulated gastrointestinal tract was as high as 65.84%. Antagonism test with a supernatant of ZDY 2013 showed maximum halo of 28 mm against Listeria monocytogenes. The inhibition order was as follows: Listeria monocytogenes, Salmonella typhimurium, Escherichia coli, Pseudomonas aeruginosa, Shigella sonnei, Enterobacter sakazakii, and Staphylococcus aureus. Lactobacillus plantarum ZDY 2013 was sensitive to some antibiotics (e.g., macrolide, sulfonamides, aminoglycoside, tetracyclines and ß-lactams), whereas it was resistant to glycopeptides, quinolones, and cephalosporins antibiotics. Denaturing gradient gel electrophoresis profile demonstrated that ZDY 2013 administration altered the composition of the microbiota at various intestinal loci of the mice. Moreover, the quantitative PCR test showed that the administration of ZDY 2013 enhanced the populations of Bifidobacterium and Lactobacillus in either the colon or cecum, and reduced the potential enteropathogenic bacteria (e.g., Enterococcus, Enterobacterium, and Clostridium perfringens). Lactobacillus plantarum ZDY 2013 exhibited high resistance against low pH, bile salt, and gastrointestinal fluid, and possessed antibacterial and gut microbiota modulation properties with a potential application in the development of dairy food and nutraceuticals.

Molecular Cloning, Prokaryotic Expression, and Immunological Characterization of ß-Enolase from Grass Carp (Ctenopharyngodon idella).

ß-Enolase is a cross-allergen commonly found in fungi, plants, and aquatic products. Although studies on the allergenicity of fish enolase have been reported in recent years, they are still limited to a few species of marine fish. Therefore, the detection of freshwater fish in the food industry requires more studies of the molecular characterization as well as the allergenicity of enolase. In this study, the nucleotide sequence of ß-enolase from grass carp was obtained by molecular cloning technology. Structural domain analysis showed that it contained the characteristic structural domains of the enolase superfamily, and homology analysis indicated that enolases are highly conserved evolutionarily. Recombinant ß-enolase was obtained by prokaryotic expression, and its allergenicity was assessed by ß-enolase-sensitized mice, which confirmed the ability of ß-enolase to trigger an allergic response and cause a rise in Th1 and Th2 immune responses in mice. These results suggest that ß-enolase could be used as a characterizing substance for the detection of fish allergens in the food industry as well as the preparation of drugs for allergy-related studies.

Lactiplantibacillus plantarum ZDY2013 Inhibits the Development of Non-Alcoholic Fatty Liver Disease by Regulating the Intestinal Microbiota and Modulating the PI3K/Akt Pathway.

Non-alcoholic fatty liver disease (NAFLD) is a common chronic hepatic condition whose impact on human health is increasingly significant. The imbalance of the gut microbiome, linked to insulin resistance, heightened intestinal permeability, and pro-inflammatory reactions, may be the linchpin in the development of NAFLD. In our research, the impact of Lactiplantibacillus plantarum ZDY2013 administration for 12 weeks on gut microbiota dysbiosis induced by a high-fat, high-fructose, high-cholesterol (FHHC) diet in male C57BL/6n mice was investigated. Research results presented that the intervention of L. plantarum ZDY2013 in mice fed with the FHHC diet could restore their liver function and regulate oxidative stress. Compared to mice in the model group, the intervention of L. plantarum ZDY2013 significantly regulated the gut microbiota, inhibited the LPS/NF-κB pathway, and led to a lower level of colonic inflammation in the mice administered with L. plantarum ZDY2013. It also improved insulin resistance to regulate the PI3K/Akt pathway and lipid metabolism, thereby resulting in reduced fat accumulation in the liver. The above results suggest that the intervention of L. plantarum ZDY2013 can hinder the progression of diet-induced NAFLD by reducing inflammation to regulate the PI3K/Akt pathway and regulating gut microbiota disturbance.

The flavor substances changes in Fuliang green tea during storage monitoring by GC-MS and GC-IMS.

To study the effect of storage (for 0, 3, 6, and 12 months) on the flavor of green tea (GT), we monitored the volatile organic compounds (VOCs) in GT through gas chromatography (GC) combined with ion mobility spectrometry and headspace solid-phase micro extraction, GC-MS (mass spectrometry). Then, relative odor activity value (ROAV) was applied to analyze the aroma contribution of the VOCs. During storage, the polyphenol and caffeine contents gradually decreased from 22.38 % to 18.51 % and from 4.37 % to 3.74 %, respectively, and the total soluble sugar first increased and then decreased (from 4.89 % to 7.16 % and then 5.02 %). Although the total free amino acid contents showed a fluctuating trend, the content of cysteamine increased gradually. The contents of VOCs with positive contribution to GT aroma, including linalool, geraniol, nonanal, and 6-methyl-5-hepten-2-one, decreased. They also contributed less in the ROAV after storage. The ROAVs of nonanal, linalool, and geraniol decreased from 3.37 to 0.79, from 100 to 38.21, and from 2.98 to 1.8, respectively, after 12 months of storage. Principal component analysis can be used to identify the samples with different storage durations based on these data. Given the increase in amount of cysteamine and decrease in that of linalool oxide, oxidation may be not the only factor responsible for tea quality in storage.

Antibacterial activity and mechanism of action of ε-poly-L-lysine.

ε-Poly-L-lysine (ε-PL)(2) is widely used as an antibacterial agent because of its broad antimicrobial spectrum. However, the mechanism of ε-PL against pathogens at the molecular level has not been elucidated. This study investigated the antibacterial activity and mechanism of ε-PL against Escherichia coli O157:H7 CMCC44828. Propidium monoazide-PCR test results indicated that the threshold condition of ε-PL for complete membrane lysis of E. coli O157:H7 was 10 µg/mL (90% mortality for 5 µg/mL). Further verification of the destructive effect of ε-PL on cell structure was performed by atomic force microscopy and transmission electron microscopy. Results showed a positive correlation between reactive oxygen species (ROS)(3) levels and ε-PL concentration in E. coli O157:H7 cells. Moreover, the mortality of E. coli O157:H7 was reduced when antioxidant N-acetylcysteine was added. Results from real-time quantitative PCR (RT-qPCR)(4) indicated that the expression levels of oxidative stress genes sodA and oxyR were up-regulated 4- and 16-fold, respectively, whereas virulence genes eaeA and espA were down-regulated after ε-PL treatment. Expression of DNA damage response (SOS response)(5) regulon genes recA and lexA were also affected by ε-PL. In conclusion, the antibacterial mechanism of ε-PL against E. coli O157:H7 may be attributed to disturbance on membrane integrity, oxidative stress by ROS, and effects on various gene expressions, such as regulation of oxidative stress, SOS response, and changes in virulence.

Magnetic nano-beads based separation combined with propidium monoazide treatment and multiplex PCR assay for simultaneous detection of viable Salmonella Typhimurium, Escherichia coli O157:H7 and Listeria monocytogenes in food products.

We developed a rapid and reliable technique for simultaneous detection of Salmonella Typhimurium, Escherichia coli O157:H7 and Listeria monocytogenes that can be used in food products. Magnetic nano-beads (MNBs) based immunomagnetic separation (IMS) was used to separate the target bacterial cells while multiplex PCR (mPCR) was used to amplify the target genes. To detect only the viable bacteria, propidium monoazide (PMA) was applied to selectively suppress the DNA detection from dead cells. The results showed the detection limit of IMS-PMA-mPCR assay was about 10(2) CFU/ml (1.2 × 10(2) CFU/ml for S. Typhimurium, 4.0 × 10(2) CFU/ml for E. coli O157:H7 and 5.4 × 10(2) CFU/ml for L. monocytogenes) in pure culture and 10(3) CFU/g (5.1 × 10(3) CFU/g for S. Typhimurium, 7.5 × 10(3) CFU/g for E. coli O157:H7 and 8.4 × 10(3) CFU/g for L. monocytogenes) in spiking food products samples (lettuce, tomato and ground beef). This report has demonstrated for the first time, the effective use of rapid and reliable IMS combined with PMA treatment and mPCR assay for simultaneous detection of viable S. Typhimurium, E. coli O157:H7 and L. monocytogenes in spiked food samples. It is anticipated that the present approach will be applicable to simultaneous detection of the three target microorganisms for practical use.

In Vitro Probiotic Properties of Bifidobacterium animalis subsp. lactis SF and Its Alleviating Effect on Non-Alcoholic Fatty Liver Disease.

Nonalcoholic fatty liver disease (NAFLD) is a common chronic liver disease with many influencing factors. With the increasing role of the gut-liver axis in various liver diseases, research on the prevention and treatment of NAFLD with probiotics is increasing. In the present study, a Bifidobacterium animalis subsp. strain, B. lactis SF, was isolated from the feces of healthy infants and characterized by sequencing of the 16S rDNA. A systematic probiotic evaluation was carried out, and a diet-induced mouse model was constructed to study the effect and mechanism of B. lactis SF on diet-induced NAFLD. Results show that B. lactis SF has excellent gastrointestinal fluid tolerance and intestinal colonization, and strong antibacterial and antioxidant capabilities. In vivo, B. lactis SF modulated intestinal flora, restored the intestinal barrier, and inhibited LPS entrance into the portal circulation, which subsequently inhibited the TLR4/NF-κB and modulated the PI3K-Akt/AMPK signaling pathway, attenuated the inflammatory response, and reduced lipid accumulation. In addition, B. lactis SF attenuated oxidative stress and further alleviated autophagy, resulting in an ameliorative effect on NAFLD. Therefore, our study provides a new dietary method for the treatment of NAFLD.

Prospects of Probiotic Adjuvant Drugs in Clinical Treatment.

In modern society, where new diseases and viruses are constantly emerging, drugs are still the most important means of resistance. However, adverse effects and diminished efficacy remain the leading cause of treatment failure and a major determinant of impaired health-related quality of life for patients. Clinical studies have shown that the disturbance of the gut microbial structure plays a crucial role in the toxic and side effects of drugs. It is well known that probiotics have the ability to maintain the balance of intestinal microecology, which implies their potential as an adjunct to prevent and alleviate the adverse reactions of drugs and to make medicines play a better role. In addition, in the past decade, probiotics have been found to have excellent prevention and alleviation effects in drug toxicity side effects, such as liver injury. In this review, we summarize the development history of probiotics, discuss the impact on drug side effects of probiotics, and propose the underlying mechanisms. Probiotics will be a new star in the world of complementary medicine.

Targeting the gut microbiota to investigate the mechanism of Lactiplantibacillus plantarum 1201 in negating colitis aggravated by a high-salt diet.

High-salt diet (HSD) affects the composition and function of the intestinal microbiota and cause health problems. This study confirmed that HSD aggravates dextran sulphate sodium (DSS)-induced colitis by changing the relative abundance of the gut microbiota, activating the NF-κB pathway, and up-regulating the mRNA levels of inflammatory factors. We explored the effect of L. plantarum 1201 in negating DSS-induced ulcerative colitis, which is aggravated by HSD for the first time. Results show that L. plantarum 1201 rebuilt the balance of intestinal flora by decreasing the ratio of Firmicutes/Bacteroidetes and increasing the relative abundance of Bifidobacterium, Lactobacillus and butyric-producing bacteria. Moreover, L. plantarum 1201 inhibited the up-regulation of inflammatory cytokines (e.g., IL-1ß, TNF-α, IL-6, IL-22, and IFN-γ) mRNA levels, increased colonic tight junction protein (ZO-1, ocludin, and claudin-3) expression, and increased serum levels of beneficial metabolites, including alpha-tocopherol (α-T) and D-mannose. By reconstructing an animal model of colitis, we further discovered that α-T and D-mannose inhibited the NF-κB pathway, improved tissue injury, and decreased the expression of pro-inflammatory cytokines (e.g., IL-1ß, TNF-α, and IL-6). This study proves for the first time that L. plantarum 1201 attenuates high-salt-aggravated colitis by increasing the serum concentrations of endogenic D-mannose in mice serum and inhibiting the consumption of α-T through intestinal flora. Therefore, regulating the gut microbiota is a potential treatment for high-salt-aggravated colitis.

Lactiplantibacillus plantarum 1201 Inhibits Intestinal Infection of Salmonella enterica subsp. enterica Serovar Typhimurium Strain ATCC 13311 in Mice with High-Fat Diet.

Salmonella Typhimurium is widely distributed in food. It can colonise the gastrointestinal tract after ingestion, causing lamina propria edema, inflammatory cell infiltration, and mucosal epithelial decomposition. A high-fat diet (HFD) can induce an inflammatory response, but whether HFD can increase the infection level of S. Typhimurium is unknown. We established a model of Salmonella enterica subsp. enterica serovar Typhimurium strain ATCC 13311 ATCC 13311 infection in healthy adult mice with a maintenance diet (MD) or HFD to explore the effect of Lactiplantibacillus plantarum 1201 intervention on S. Typhimurium ATCC 13311 colonization and its protective effects on mice. HFD exacerbated the infection of S. Typhimurium ATCC 13311, while the intervention of L. plantarum 1201 effectively mitigated this process. L. plantarum 1201 can reduce the colonies of S. ATCC 13311 in the intestines and tissues; and reduce intestinal inflammation by down-regulating the level of TLR4/NF-κB pathway related proteins in serum and the expression of related inflammatory factors in the colon and jejunum. Since L. plantarum 1201 can inhibit the colonization of S. Typhimurium ATCC 13311 and relieve inflammation in HFD, current research may support the use of L. plantarum 1201 to prevent S. Typhimurium infection.