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Chinese sour bamboo shoot is a traditionally, spontaneous fermented food that is particularly popular due to its complex and distinctive flavor. The volatile compounds of sour bamboo shoot originate mainly from the raw materials and the microbial fermentation. To reveal the correlation between microorganisms and flavor, third-generation sequencing and Gas Chromatography-Ion Mobility Spectrometry were applied to analyze the dynamics of microbial communities at the species level and volatile compounds during sour bamboo shoot fermentation. The abundance of Lactobacillus acetotolerans and Lactobacillus fermentum increased during the fermentation, while Lactobacillus amyloliquefaciens decreased at first but then began to rise. At the end of fermentation, Lactobacillus amyloliquefaciens and Lactobacillus acetotolerans became the predominant species. A total of sixty-seven volatile compounds, which included twenty-three esters, nineteen alcohols, eight ketones, six aldehydes, six aromatic hydrocarbons, four acids and one ether, were identified. These compounds constituted the primary flavor of sour bamboo, which created a complex flavor of sour bamboo shoot. Among them, the contents of acetic acid, propionic acid, and isoamyl alcohol gradually increased during the fermentation process, and they became the main volatile compounds. Furthermore, the correlation between microorganisms and volatile compounds was investigated through two-way Orthogonal Partial Least Squares (O2PLS), which revealed a positive correlation between Lactobacillus amylolyticus and ethyl propanoate. Additionally, the abundance of Lactobacillus acetotolerans and Lactobacillus fermentum was found to be positively correlated with 2-heptenal. These findings provide a theoretical basis for understanding the formation mechanism of sour bamboo shoot flavor and the standardized production of high-quality sour bamboo shoots. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is a significant health concern and is the third most commonly diagnosed and second deadliest cancer worldwide. CRC has been steadily increasing in developing countries owing to factors such as aging and epidemics. Despite extensive research, the exact pathogenesis of CRC remains unclear, and its causes are complex and variable. Numerous in vitro, animal, and clinical trials have demonstrated the efficacy of probiotics such as Lactobacillus plantarum in reversing the adverse outcomes of CRC. These findings suggest that probiotics play vital roles in the prevention, adjuvant treatment, and prognosis of CRC. In this study, we constructed a mouse model of CRC using an intraperitoneal injection of azomethane combined with dextran sodium sulfate, while administering 5-fluorouracil as well as high- and low-doses of L. plantarum Zhang-LL live or heat-killed strains. Weight changes and disease activity indices were recorded during feeding, and the number of polyps and colon length were measured after euthanasia. HE staining was used to observe the histopathological changes in the colons of mice, and ELISA was used to detect the expression levels of IL-1β, TNF-α, and IFN-γ in serum. To investigate the specific mechanisms involved in alleviating CRC progression, gut microbial alterations were investigated using 16S rRNA amplicon sequencing and non-targeted metabolomics, and changes in genes related to CRC were assessed using eukaryotic transcriptomics. The results showed that both viable and heat-killed strains of L. plantarum Zhang-LL in high doses significantly inhibited tumorigenesis, colon shortening, adverse inflammatory reactions, intestinal tissue damage, and pro-inflammatory factor expression upregulation. Specifically, in the gut microbiota, the abundance of the dominant flora Acutalibacter muris and Lactobacillus johnsonii was regulated, PGE2 expression was significantly reduced, the arachidonic acid metabolism pathway was inhibited, and CD22-mediated B-cell receptor regulation-related gene expression was upregulated. This study showed that L. plantarum Zhang-LL live or heat-inactivated strains alleviated CRC progression by reducing the abundance of potentially pathogenic bacteria, increasing the abundance of beneficial commensal bacteria, mediating the arachidonic acid metabolism pathway, and improving host immunogenicity. [ABSTRACT FROM AUTHOR]

Excessive drinking can significantly damage people's health and well-being. Although some lactic acid bacterial strains have been previously shown to alleviate the symptoms of alcohol injury, the mechanism underlying these effects remains unclear. The aim of this study was to establish an alcohol injury model and examine the protective effect and mechanism of B. animalis A12 and L. salivarius M18-6. The results showed that A12 freeze-dried powder could maintain the survival rate of mice with alcohol injury at 100%. Compared with Alco group, L. salivarius M18-6 dead cell improved the survival rate of mice, attenuated liver steatosis, and significantly down-regulated serum Alanine transaminase (ALT) level; at the same time, it activated keap1-Nrf2 signaling pathway and up-regulated Superoxide dismutase (SOD), it protects mouse liver cells from oxidative stress induced by alcohol injury. In addition, B. animalis A12 can reduce the stress response to short-term alcohol intake and improve the ability of anti-oxidative stress by upregulating the level of isobutyric acid, reducing the level of keap1 protein in the liver of mice and upregulating the expression of thioredoxin genes (Txnrd1, Txnrd3, Txn1). Taken together, the results showed that B. animalis A12 and L. salivarius M18-6 alleviate alcohol injury in mice through keap1-Nrf2 signaling pathway and thioredoxin system. [ABSTRACT FROM AUTHOR]

Bifidobacterium animalis A12 was used for the development of fermented sausage. The growth activity, tolerance, and enzyme activity of B. animalis A12 and its contribution to the texture and flavour of fermented sausages were evaluated. Additionally, the sensory texture, flavour components, and amino acid nutrients during the fermentation process were assessed. B. animalis had high tolerance to NaCl and nitrite, and B. animalis A12 had protease and lipase activities. The pH value of sausage fermented with B. animalis A12 was lower than that of sausage fermented without any fermentation strain. Hexanal, heptanal, decanal, cis-2-decanal, and 4-methoxy-benzaldehyde are the unique aldehydes flavour components of fermented sausages in the A12 group. The highest content of volatile flavour substances and amino acids, and the color and texture characteristics of fermented sausage in the experimental group at 18 h were better than those at other times. These results suggest that B. animalis A12 has the potential to be used as a starter culture for im-proving flavour and texture in fermented sausage. [ABSTRACT FROM AUTHOR]

Salmonella is one of the most widely distributed and harmful food-borne pathogens; thus, the rapid detection of viable Salmonella is important for ensuring food safety. In this study, a rapid visual strategy based on loop-mediated isothermal amplification (LAMP) with the addition of thermal inorganic pyrophosphatase and linked with an ammonium molybdate chromogenic buffer was established to detect Salmonella. Specific primers were designed based on the phoP gene of Salmonella spp. The pyrophosphatase concentration, LAMP time, addition of ammonium molybdate chromogenic buffer, and color reaction time were optimized. Based on the optimal conditions, the sensitivity and specificity of the method were examined. In addition, the ability to detect actual samples was verified using apple juice containing Salmonella. LAMP was performed at 65°C for 45 min in the presence of thermal inorganic pyrophosphatase at a final concentration of 4 U ml−1, and 20 μl of the LAMP product was reacted with 50 μl of phosphate chromogenic buffer at 25°C for 15 min. According to our results, the limit of detection of the LAMP assay for viable Salmonella was 1.83 × 102 CFU per reaction, and nonspecific amplification was not observed. The detection rates of Salmonella Typhimurium with different concentrations in apple juice were 89.11%–94.80%, which verifies that the visual detection strategy is suitable for actual sample detection. [ABSTRACT FROM AUTHOR]

Bifidobacterium, a common probiotic, is widely used in the food industry. Hyperglycemia in pregnancy has become a common disease that impairs the health of the mother and can lead to adverse pregnancy outcomes, such as preeclampsia, macrosomia, fetal hyperinsulinemia, and perinatal death. Currently, Bifidobacterium has been shown to have the potential to mitigate glycolipid derangements. Therefore, the use of Bifidobacterium-based probiotics to interfere with hyperglycemia in pregnancy may be a promising therapeutic option. We aimed to determine the potential effects of Bifidobacterium animalis subsp. lactis J-12 (J-12) in high-fat diet (HFD)/streptozotocin (STZ)-induced rats with hyperglycemia in pregnancy (HIP) and respective fetuses. We observed that J-12 or insulin alone failed to significantly improve the fasting blood glucose (FBG) level and oral glucose tolerance; however, combining J-12 and insulin significantly reduced the FBG level during late pregnancy. Moreover, J-12 significantly decreased triglycerides and total cholesterol, relieved insulin and leptin resistance, activated adiponectin, and restored the morphology of the maternal pancreas and hepatic tissue of HIP-induced rats. Notably, J-12 ingestion ameliorated fetal physiological parameters and skeletal abnormalities. HIP-induced cardiac, renal, and hepatic damage in fetuses was significantly alleviated in the J-12-alone intake group, and it downregulated hippocampal mRNA expression of insulin receptor (InsR) and insulin-like growth factor-1 receptor (IGF-1R) and upregulated AKT mRNA on postnatal day 0, indicating that J-12 improved fetal neurological health. Furthermore, placental tissue damage in rats with HIP appeared to be in remission in the J-12 group. Upon exploring specific placental microbiota, we observed that J-12 affected the abundance of nine genera, positively correlating with FBG and leptin in rats and hippocampal mRNA levels of InsR and IGF-1R mRNA in the fetus, while negatively correlating with adiponectin in rats and hippocampal levels of AKT in the fetus. These results suggest that J-12 may affect the development of the fetal central nervous system by mediating placental microbiota via the regulation of maternal-related indicators. J-12 is a promising strategy for improving HIP and pregnancy outcomes. [ABSTRACT FROM AUTHOR]

Shigella spp. and enteroinvasive Escherichia coli (EIEC) are widely distributed and can cause serious food-borne diseases for humans such as dysentery. Therefore, an efficient detection platform is needed to detect Shigella and EIEC quickly and sensitively. In this study, a method called recombinase polymerase amplification combined with lateral flow dipstick (RPA-LFD) was developed for rapid detection of Shigella and EIEC. RPA primers and LFD detection probes were designed for their shared virulence gene ipaH. Primers and probes were screened, and the primer concentration, and reaction time and temperature were optimized. According to the optimization results, the RPA reaction should be performed at 39°C, and when combined with LFD, it takes less than 25 min for detection with the naked eye. The developed RPA-LFD method specifically targets gene ipaH and has no cross-reactivity with other common food-borne pathogens. In addition, the minimum detection limit of RPA-LFD is 1.29×102 copies/μL. The detection of food sample showed that the RPA-LFD method was also verified for the detection of actual samples. [ABSTRACT FROM AUTHOR]

BACKGROUND Probiotics are defined as microorganisms that can exert health benefits for the host. Among the recognized probiotics, Lactobacillus paracasei are one of the most frequently used probiotics in humans. The L. paracasei strain M11‐4, isolated from fermented rice (which could ferment soymilk within a short curd time) and fermented soymilk presented high viability, acceptable flavor, and antioxidant activity, which revealed that the strain maybe have a potential antioxidant value. Therefore, it is necessary to further explore the antioxidant activity of L. paracasei strain M11‐4. RESULTS: The radical scavenging activities, lipid peroxidation inhibition, and reducing power of L. paracasei M11‐4 were the highest in the fermentation culture without cells, whereas the activities of other antioxidant enzymes of L. paracasei M11‐4 were high in the cell‐free extract and bacterial suspension. Moreover, L. paracasei M11‐4 exerted its antioxidant effect by upregulating the gene expression of its antioxidant enzymes – the thioredoxin and glutathione systems – when hydrogen peroxide existed. Supplementation of rats with L. paracasei M11‐4 effectively alleviated d‐galactose‐induced oxidative damage in the liver and serum and prevented d‐galactose‐induced changes to intestinal microbiota. Supplementation with L. paracasei M11‐4 also reduced the elevated expression of thioredoxin and glutathione system genes induced by d‐galactose. CONCLUSION: L. paracasei M11‐4 has good antioxidant properties both in vitro and in vivo, and its antioxidant mechanism was studied at the molecular level. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Plantaricin BM-1, a class IIa bacteriocin produced by Lactiplantibacillus plantarum BM-1, exhibits significant antibacterial activity against many gram-positive and gram-negative bacteria. However, the mechanism underlying the action of class IIa bacteriocins against gram-negative bacteria remains to be explored. This study aimed to investigate the role of the BasS/BasR two-component system (TCS) in Escherichia coli (E. coli) K12 response to plantaricin BM-1. The IC50 values for plantaricin BM-1 in E. coli K12, basS mutant (E. coli JW4073), and basR mutant (E. coli JW4074) strains were found to be 10.85, 8.94, and 7.62 mg/mL, respectively. Growth curve experiments showed that mutations in the BasS/BasR TCS led to an increase in the sensitivity of E. coli K12 to plantaricin BM-1 and that after gene complementation, the complemented mutant strain regained its original sensitivity. Proteomic analysis showed that 100 and 26 proteins were upregulated and 62 and 58 proteins were downregulated in E. coli JW4073 and E. coli JW4074, respectively. These differential proteins, which exhibited different molecular functions and participated in different molecular pathways, were mainly concentrated in the cytoplasm. More specifically, mutations in basS and basR were found to affect the synthesis and metabolism of many substances in E. coli , including many important amino acids and enzymes involved in cellular activities. In addition, 14 proteins, including 8 proteins involved in the tricarboxylic acid (TCA) cycle, were found to be downregulated in both E. coli JW4073 and E. coli JW4074. Growth curve experiments showed that the deletion of these proteins could increase the sensitivity of E. coli to plantaricin BM-1. Therefore, we speculate that TCA pathway regulation may be an important mechanism by which the BasS/BasR TCS regulates the sensitivity of E. coli to plantaricin BM-1. This finding will facilitate the determination of the mechanism underlying the action of class IIa bacteriocins against gram-negative bacteria. [ABSTRACT FROM AUTHOR]

Probiotics can improve dyslipidemia and promote metabolic control as a therapeutic approach for type 2 diabetes mellitus (T2DM). The hypoglycemic effects of space‐induced Lactobacillus plantarum SS18‐5 on T2DM were explored in 4‐week‐old male Sprague Dawley rats. The normal (N) group was fed a basal diet, while the other groups received a high glucose fat diet. T2DM was established by streptozotocin injection and the T2DM rats were randomly divided into three groups, a diabetic (D) group (T2DM rats treated with saline only), GS18 group (T2DM rats treated with 109 CFU/ml of L. plantarum GS18), and SS18‐5 group (T2DM rats treated with 109 CFU/ml of L. plantarum SS18‐5). After continuous gavage for 6 weeks, blood biochemical indices were measured and livers were collected for histopathological examination. The colon contents were collected for counting of Escherichia coli, Clostridium perfringens, and Lactobacillus sp. The results showed that L. plantarum SS18‐5 effectively controlled the weight of rats, reduced levels of fasting blood glucose, glycosylated hemoglobin, and insulin, increased liver glycogen levels, improved abnormal metabolism of blood lipids, enhanced the effect of anti‐lipid peroxidation, alleviated chronic inflammation and fatty liver disease, and regulated the intestinal microbiota by reducing the numbers of E. coli and C. perfringens, and increasing the numbers of Lactobacillus sp. From these results, we conclude that space‐induced L. plantarum SS18‐5 has the potential to improve T2DM by alleviating hypoglycemia and regulating the intestinal microbiota. Practical applications: With the exploration of the universe, a large number of studies have observed the changes of microorganisms in space flight, which provided a new method for high‐quality microbial pharmaceuticals in the space environment. In this study, the space environment mutated.Lactobacillus plantarum SS18‐5 can effectively improve the blood glucose of rats with type 2 diabetes, relieve oxidative stress, reduce blood lipid content, enhance immune capacity, and regulate intestinal microflora, which has potential use in the treatment of type 2 diabetes. [ABSTRACT FROM AUTHOR]

Plantaricin BM-1, a class IIa bacteriocin produced by Lactobacillus plantarum BM-1, shows obvious antibacterial activity against Escherichia coli. However, the mechanism underlying the action of class IIa bacteriocins against gram-negative bacteria remains to be explored. The purpose of this study was to investigate the role of YbfA, a DUF2517 domain-containing protein, in the response of Escherichia coli K12 to plantaricin BM-1. The growth curve experiment and MIC experiment showed that the sensitivity of E. coli to plantaricin BM-1 was decreased by a ybfA null mutation. Electron microscopy showed that the ybfA null mutation reduced the surface rupture and contraction caused by plantaricin BM-1, and mitigated the effect of plantaricin BM-1 on the morphology of the E. coli cell membrane. Proteomics analysis showed that 323 proteins were differentially expressed in E. coli lacking the ybfA gene (P < 0.05); 118 proteins were downregulated, and 205 proteins were upregulated. The metabolic pathways containing the upregulated proteins mainly included outer membrane proteins, integral components of the plasma membrane, regulation of cell motility, and regulation of locomotion. The metabolic pathways involving the downregulated proteins mainly included outer membrane protein glycine betaine transport, amino-acid betaine transport, and transmembrane signaling receptor activity. The results of the proteomics analysis showed that the protein expression of the BasS/BasR two-component system was significantly increased (P < 0.05). Moreover, the expression levels of downstream proteins regulated by this two-component system were also significantly increased, including DgkA, FliC, and MlaE, which are involved in cell membrane structure and function, and RT-qPCR also confirmed this result. The growth curve showed that the sensitivity of E. coli to plantaricin BM-1 was significantly increased due to deletion of the BasS/BasR two-component system. Thus, deletion of ybfA in E. coli can increase the expression of the BasS/BasR two-component system and positively regulate the structure and function of the cell membrane to reduce the sensitivity to plantaricin BM-1. This will help to explore the mechanism of action of class IIa bacteriocins against gram-negative bacteria. [ABSTRACT FROM AUTHOR]

BACKGROUND Probiotics are defined as microorganisms that can exert health benefits for the host. Among the recognized probiotics, Bifidobacterium are the most frequently used probiotics in humans. The aim of this study was to evaluate the antidiabetic activity of Bifidobacterium strains isolated from breastfed infant faeces, both in vitro, using the Caco‐2 monolayer transwell model, and in vivo, using a mice model of impaired glucose tolerance induced by a high‐fat diet (HFD). RESULTS: The cell‐free supernatant of Bifidobacterium lactis A12 showed better inhibitory activity of α‐glucosidase and inhibited the glucose absorption and transport than B. lactis BB12, which is a typical probiotic with antidiabetic capabilities. B. lactis A12 improved the impaired glucose intolerance, restored islet function and morphology with insulin resistance induced by the HFD in C57BL/6J mice. Furthermore, in small intestine tissues, the cell‐free supernatant of B. lactis A12 decreased the messenger RNA expressions of sucrase‐isomaltase, live B. lactis A12 cells decreased glucose transporters 2. B. lactis A12 significantly stimulated the glucagon like peptide‐1 (GLP‐1) secretion and upregulated proglucagon messenger RNA levels. CONCLUSION: B. lactis A12 protect against the deleterious effects of HFD‐induced diabetes by inhibiting the utilization, absorption, and transport of glucose by intestinal epithelial cells and promoting the expression and secretion of GLP‐1. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Plantaricin BM-1 is a class IIa bacteriocin with a strong bactericidal effect on gram-positive bacteria. Although plantaricin BM-1 also inhibits the growth of some gram-negative bacteria, including Escherichia coli, the mechanism is not clear. In this study, we used tandem mass tag-based quantitative proteomics analysis to examine the inhibitory mechanism of plantaricin BM-1 against E. coli K12, and evaluated the morphological effects by electron microscopy. The results demonstrated that plantaricin BM-1 inhibits the growth of E. coli K12 by bacteriostatic action, mainly acting on the surface of the cell wall, leading to its collapse. Proteomic analysis identified 976 differentially expressed proteins (>1.2-fold change, p < 0.05) under treatment with plantaricin BM-1, including 490 up-regulated proteins and 486 down-regulated proteins. These proteins were mainly involved in peptidoglycan synthesis and energy metabolism pathways, including amino acid, glyoxylate and dicarboxylate, ABC transporter, and quorum-sensing pathways. Specifically, plantaricin BM-1 treatment significantly improved peptidoglycan synthesis and enhanced the tricarboxylic acid cycle in E. coli K12, and altered the expression of cell membrane proteins. These results provide new insight into the inhibition mechanism of class IIa bacteriocins on gram-negative bacteria, which can lay the foundation for its broader use as an alternative to conventional antibiotics. [ABSTRACT FROM AUTHOR]

In this study, an active antibacterial packaging film was developed by coating a polyethylene terephthalate/polyvinylidene chloride/retort casting polypropylene (PPR) plastic multilayer film with plantaricin BM‐1 and chitosan. The characteristics of the active packaging film and its antibacterial effect for chilled meat preservation were evaluated. Our results indicated that the barrier properties against oxygen were improved significantly and the tensile strength and the elongation at break were changed slightly. The active plantaricin film significantly (P < 0.05) decreased the viable counts of Listeria monocytogenes by 3.6 log10CFU/mL in liquid medium and approximately 1.4 log10CFU/g in meat stored at 4 °C for 8 days compared with the control. Moreover, the viable counts of aerobes and anaerobes in the meat packaged with the active plantaricin film were significantly (P < 0.05) decreased by approximately 0.6 log10CFU/g and 1.1 log10CFU/g when compared with that packaged with PPR film stored at 4 °C for 12 days. The total volatile base (TVB‐N) in the meat packaged with the active plantaricin film was significantly (P < 0.05) lower than that in the control during the entire storage period. Our results indicated that the active film could extend the meat shelf life by inhibiting the L. monocytogenes and the background spoilage bacteria in chilled meat stored at 4 °C. This outcome suggests that plastic multilayer film incorporating plantaricin BM‐1 can be potentially used for fresh meat packaging. Practical Application: Fresh meat is highly perishable product. This study developed a plantaricin BM‐1 active plastic multilayer film that can inhibit the growth of microorganisms in chilled meat during storage at 4 °C. [ABSTRACT FROM AUTHOR]

Plantaricin BM-1, a typical IIa bacteriocin, is produced by Lactobacillus plantarum BM-1, which can be isolated from a traditionally fermented Chinese meat product. This bacteriocin exhibits perfect thermal stability and broad inhibitory activity against certain foodborne pathogens. In this study, we investigated the effect of plantaricin BM-1 combined with physicochemical treatments (sodium nitrite, heat treatment, ultrahigh pressure technology) on the control of Listeria monocytogenes populations in cooked ham. According to our results, the addition of sodium nitrite (0.075 or 0.15 mg/mL) significantly inhibited the growth of L. monocytogenes in broth, plantaricin BM-1 combined with heat treatment reduced the viable counts of L. monocytogenes more than plantaricin BM-1 alone, and plantaricin BM-1 combined with sodium nitrite and heat treatment had the greatest antibacterial effect in broth. However, the addition of sodium nitrite or heat treatment alone did not inhibit the growth of L. monocytogenes in cooked ham. The combined application of 5,120 arbitrary units per gram (AU/g) plantaricin BM-1 and 0.075 mg/g sodium nitrite reduced L. monocytogenes significantly more effectively (by 1.97 log CFU/g) than application of 5,120 AU/g plantaricin alone. Plantaricin BM-1 application combined with sodium nitrite and heat treatment led to viable counts of L. monocytogenes below the level of detection for 49 days of storage. Moreover, in cooked ham treated with 5,120 AU/g plantaricin BM-1, 0.075 mg/g sodium nitrite, and ultrahigh pressure technology (400 MPa for 5 min), viable counts of L. monocytogenes were reduced by 5.79 log CFU/g compared with control samples at the end of storage. In conclusion, the combination of plantaricin BM-1 with physicochemical treatments had a synergistic inhibitory effect on L. monocytogenes in cooked ham. [ABSTRACT FROM AUTHOR]

Northeastern rice is one of the best rice brand in China, which has good taste and rich in nutrition. But the difference of heavy metals and healthy trace elements in northeastern and southern rice were few reported. Nineteen northeastern rice and seventeen southern rice samples were investigated. Northeastern rice contained more Ca, Mn, Fe, Zn, and Cu, but less Se and Mo as compared to southern rice. But southern rice contained more Cd and Cr; especially Cd often exceeded than national standard. All these data should be related to the content of these elements in soil. In summary, we can conclude that northern rice is more nutritional and safer than southern rice in China. [ABSTRACT FROM AUTHOR]

Bacillus subtilis SH21 was observed to produce an antifungal protein that inhibited the growth of F. solani. To purify this protein, ammonium sulfate precipitation, gel filtration chromatography, and ion-exchange chromatography were used. The purity of the purified product was 91.33% according to high-performance liquid chromatography results. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis and liquid chromatography–tandem mass spectrometry (LC–MS/MS) analysis revealed that the molecular weight of the protein is 30.72 kDa. The results of the LC–MS/MS analysis and a subsequent sequence-database search indicated that this protein was a chitosanase, and thus, we named it chitosanase SH21. Scanning and transmission electron microscopy revealed that chitosanase SH21 appeared to inhibit the growth of F. solani by causing hyphal ablation, distortion, or abnormalities, and cell-wall depression. The minimum inhibitory concentration of chitosanase SH21 against F. solani was 68 µg/mL. Subsequently, the corresponding gene was cloned and sequenced, and sequence analysis indicated an open reading frame of 831 bp. The predicted secondary structure indicated that chitosanase SH21 has a typical a-helix from the glycoside hydrolase (GH) 46 family. The tertiary structure shared 40% similarity with that of Streptomyces sp. N174. This study provides a theoretical basis for a topical cream against fungal infections in agriculture and a selection marker on fungi. [ABSTRACT FROM AUTHOR]

In this study, we focused on the successful construction of [(4,4′-bipy/P 2 Mo 17 Co) 6 ] modified electrodes using the layer-by-layer assembly method for the sensitive detection of sulfathiazole (ST). The redox reaction between ST and the metal ions in the modified layer leads to the transfer of electrons, resulting in the generation of the electrical signal. The introduction of 4,4′-bipyridine (4,4′-bipy) enhanced the molecular recognition of ST by the modified electrode. Under the combined effect of P 2 Mo 17 Co and 4,4′-bipy, the sensor exhibited good performance for ST detection (LOD: 0.5616 μM, linear ST concentration range: 0–50 μM). The spiked recoveries of the two groups were 84.4%–103.2% and 90.9%–109.4% for the determination of ST residues in large yellow croaker and South American white shrimp, respectively. In addition, the electrode showed excellent performance in terms of stability, reproducibility, and anti-interference ability. [Display omitted] • Rapid detection and quantitative analysis of sulfathiazole residues in aquatic products. • A novel POMs electrochemical sensor for sulfonamide residue analysis was developed. • Preparation of [(4,4′-bipy/P 2 Mo 17 Co) 6 ] modified electrodes using the LBL method. • Modified electrodes based on P 2 Mo 17 Co and 4,4′-bipyridine improved detection sensitivity. [ABSTRACT FROM AUTHOR]

• Chronic UC rats Gavaged with live or heat-killed cells were of 100% survival rate. • Live and heat-killed cells increased intestinal flora diversity of Chronic UC rats. • Live and heat-killed cells reduced intestinal permeability of Chronic UC rats. • Heat-killed cells were more effective against chronic UC in rats than live cells. Controversial results were yielded in some studies on the effects of Lactobacillus on ulcerative colitis (UC). In this work, we evaluated the effect of live or heat-killed Lactobacillus plantarum Zhang-LL cells and cell supernatants on dextran sulfate sodium (DSS)-induced UC in rats. The tested subjects were gavaged to rats for 7 days, and then 5% was used DSS repeatedly to induce chronic UC. The results of a 42-day experiment, indicated consistently and significantly that Both living and heat-killed cells of L. plantarum Zhang-LL could down-regulate content of pro-inflammatory cytokines (TNF-α, INF-γ) in serum, reduce intestinal permeability by increasing the expression of tight junction proteins zo-1, claudin-1 and occludin in colon tissue, and maintain intestinal microbiota stability by increasing intestinal microbiota diversity to alleviate the symptoms of chronic UC in rats with 100% survival rate. Of concern is, the heat-killed cells of L. plantarum Zhang-LL were more effective against DSS-induced chronic UC in rats. [ABSTRACT FROM AUTHOR]