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Six new nonadride derivatives, named talarodrides A-F (1-6), were isolated from the Antarctic sponge-derived fungus Talaromyces sp. HDN1820200. All structures including the absolute configurations were deduced by extensive spectroscopic analysis and computational ECD calculations. Compounds 1-4 share a rare caged bicyclo[4.3.1]-deca-1,6-diene with a bridgehead olefin and maleic anhydride core skeleton, while compounds 5 and 6 possess the first case of a naturally occurring 5/7/6 methanocyclonona[c]furan skeleton. Talarodride A (1) and talarodride B (2) showed selective inhibitory effects against Proteus mirabilis and Vibrio parahemolyticus with MICs of 3.13-12.5 μM.

Fresh foods are vulnerable to foodborne pathogens which cause foodborne illness and endanger people's life and safety. The rapid detection of foodborne pathogens is crucial for food safety surveillance. An in situ-synthesized gene chip for the detection of foodborne pathogens on fresh-cut fruits and vegetables was developed. The target genes were identified and screened by comparing the specific sequences of Salmonella Typhimurium, Vibrio parahemolyticus, Staphylococcus aureus, Listeria monocytogenes, and Escherichia coli O157:H7 from the National Center for Biotechnology Information database. Tiling array probes were designed to target selected genes in an optimized hybridization system. A total of 141 specific probes were selected from 3,227 hybridization probes, comprising 26 L. monocytogenes, 24 S. aureus, 25 E. coli O157:H7, 20 Salmonella Typhimurium, and 46 V. parahemolyticus probes that are unique to this study. The optimized assay had strong amplification signals and high accuracy. The detection limit for the five target pathogens on fresh-cut cantaloupe and lettuce was approximately 3 log cfu/g without culturing and with a detection time of 24 h. The detection technology established in this study can rapidly detect and monitor the foodborne pathogens on fresh-cut fruits and vegetables throughout the logistical distribution chain, i.e., processing, cleaning, fresh-cutting, packaging, storage, transport, and sale, and represents a valuable technology that support the safety of fresh agricultural products.

Vibrio parahemolyticus (VP) mostly isolated from aquatic products is one of the major causes of bacterial food-poisoning events worldwide, which could be reduced using a promising on-site detection method. Herein, a rapid and quantitative method for VP detection was developed by applying a mixed-dye-loaded loop-mediated isothermal amplification (LAMP) assay on a self-priming compartmentalization (SPC) microfluidic chip, termed on-chip mixed-dye-based LAMP (CMD-LAMP). In comparison to conventional approaches, CMD-LAMP was advantageous on the limit of detection, which reached down to 1 × 103 CFU/mL in food-contaminated samples without the pre-enrichment of bacteria. Additionally, as a result of the use of a mixed dye and SPC chip, the quantitative result could be easily acquired, avoiding the requirement of sophisticated instruments and tedious operation. Also, CMD-LAMP was rapid and cost-effective. Conclusively, CMD-LAMP has great potential in realizing the on-site quantitative analysis of VP for food safety.

In the Viable but Non-Culturable (VBNC) state, microorganisms may survive under severe external environment. In this study, the specificity and sensitivity of PMA-LAMP assay on the detection of Vibrio Parahemolyticus (V. parahemolyticus) has been developed and evaluated, with further application on a number of food-borne V. parahemolyticus strains. Six primers were designed for recognizing 8 distinct targeting on tlh, tdh and trh gene. Through specific penetration through the damaged cell membrane of dead cells and intercalating into DNA, PMA could prevent DNA amplification of dead bacteria from LAMP, which enabled the differentiation of bacteria between VBNC state and dead state. The established PMA-LAMP showed significant advantage in rapidity, sensitivity and specificity, compared with regular PCR assay. The applicability had also been verified, demonstrating the PMA-LAMP was capable of detection on V. parahaemolyticus.

Pathogenic Vibrio parahaemolyticus, an important foodborne bacterium, coexists with nonpathogenic strains of V. parahaemolyticus in the environment. However, current predictive models for V. parahaemolyticus usually focused on single strain without considering the pathogenic and nonpathogenic bacteria cocktail coexist situation. In this study, the behavior of four V. parahaemolyticus strains (F18: tlh+/trh+/tdh−, ATCC 17802: tlh+/trh+/tdh−, F36: tlh+/trh−/tdh−, ATCC 33847: tlh+/trh−/tdh+) and their cocktails on cooked shrimp were investigated at different temperatures (4, 7, 10, 15, 20, 25 and 30 °C). Total bacteria counts were enumerated by traditional plate count method, periodically. Results showed both V. parahaemolyticus cocktails and four single strains grew in a temperature range of 15–30 °C and died at 4–7 °C. At 10 °C, for the cocktails, it inactivated at initial 100 h and then grew rapidly; but for single strain, only one strain F18 displayed the similar growth tendency, while the others grew all the time. Compared with single strains, the primary and secondary model analysis showed that the cocktails displayed a better growth activity with higher maximum growth rate and shorter lag time. The above results indicated that modeling bacterial growth by using a cocktail of V. parahaemolyticus strains may be a better option for simulating growth in the real environment. This study will fill in the gap of predictive microbiology and improve significantly the accuracy of microbial risk assessment.

Marine-derived fungi are a rich source of structurally diverse metabolites. Fungi produce an array of compounds when grown under different cultivation conditions. In the present work, different media were used to cultivate the fungus Aspergillus sp. ZA-01, which was previously studied for the production of bioactive compounds, and three new prenylxanthone derivatives, aspergixanthones I&ndash, K (1&ndash, 3), and four known analogues (4&ndash, 7) were obtained. The absolute configuration of 1 was assigned by ECD experiment and the Mo2(AcO)4 ICD spectrum of its methanolysis derivative (1a). All the compounds (1&ndash, 7) were evaluated for their anti-Vibrio activities. Aspergixanthone I (1) showed the strongest anti-Vibrio activity against Vibrio parahemolyticus (MIC = 1.56 &mu, M), Vibrio anguillarum (MIC = 1.56 &mu, M), and Vibrio alginolyticus (MIC = 3.12 &mu, M).

Background Acute hepatopancreatic necrosis disease (AHPND) has emerged as a major debilitating disease that causes massive shrimp death resulting in substantial economic losses in shrimp aquaculture. Given that several diseases and infections have been associated with microRNAs (miRNAs), we conducted a comparative transcriptomic analysis using the AHPND (VA) and non-AHPND (VN) strains of Vibrio parahemolyticus to identify miRNAs potentially involved in AHPND pathogenesis in Litopenaeus vannamei. Results A total of 83 miRNAs (47 upregulated and 36 downregulated) were significantly differentially expressed between the VA and VN challenged groups, while 222 target genes of these miRNAs were predicted. Functional enrichment analysis revealed that the miRNAs target genes were involved in multiple biological processes including metabolic pathways, amoebiasis, Vibrio cholerae infection etc. Finally, interaction network and qPCR (Real-time Quantitative PCR) analysis of 12 potential key AHPND-related miRNAs and their predicted target genes, revealed their possible involvement in modulating several immune-related processes in the pathogenesis of AHPND. Conclusions We have shown using comparative transcriptomic analysis, miRNAs and their target genes that are responsive to AHPND V. parahemolyticus infection in shrimp, therefore suggesting their possible role in defense response to AHPND V. parahemolyticus infection. Electronic supplementary material The online version of this article (10.1186/s12864-018-4728-4) contains supplementary material, which is available to authorized users.

Vibrio alginolyticus , Vibrio parahemolyticus and Photobacterium damselae subsp damselae were isolated during recurrent episodes of mass mortalities among different stages of Gilthead sea bream ( Sparus aurata ) and European seabass ( Dicentrarchus labrax ). The pathogens were recovered from the external/internal lesions of a total of 320 seeds, juvenile and adult fishes from the period of February 2013 through August 2013. Two hundred and sixty four bacterial isolates were retrieved and presumptively identified using morpho-chemical characterization and API®20NE. However, definitive molecular confirmation of V. alginolyticus was obtained through implementing collagenase gene based regular PCR technique. The total prevalence of V. alginolyticus , V. parahemolyticus and Photobacterium damselae subsp damselae among naturally infected Gilthead seabream and European seabass was 82.19%, 87.28% 10.27%, 6.79% and 7.54%, 5.93% respectively. Antibiogram has revealed that isolates were sensitive to ciprofloxacin, chloramphenicol, enrofloxacin, nalidixic acid and oxolinic acid while resistant to ampicillin, amoxicillin, and lincomycin.

Pomegranates have health-promoting benefits because of their polyphenol constituents. Previous studies have demonstrated the antimicrobial activity of aqueous and organic extracts of pomegranate components and by-products. We sought to determine the antimicrobial activity against 40 foodborne pathogens representing eight bacterial species using juice itself. In addition, we sought to determine the synergistic antimicrobial activity between pomegranate juice and other plant products displaying antimicrobial activity. The antimicrobial activity of pomegranate juice was dependent on the test organism, which varied to highly susceptible (four Gram-positive species) to unaffected (Salmonella and Escherichia coli O157:H7). Two Gram-negative species, which were inhibited were Helicobacter pylori and Vibrio parahemolyticus. No synergistic antimicrobial activity was seen between pomegranate and either barberry, oregano, or cranberry. The antimicrobial activity of pomegranate juice is dependent on the test organism and extraction method. The sensitivity of H. pylori suggests that pomegranate juice may be an alternative or supplemental treatment for gastric ulcers caused by this organism.

Microbial growth variability plays an important role on food safety risk assessment. In this study, the growth kinetic characteristics corresponding to maximum specific growth rate (μmax) of 50 V. parahaemolyticus isolates from different sources and genotypes were evaluated at different temperatures (10, 20, 30, and 37°C) and salinity (0.5, 3, 5, 7, and 9%) using the automated turbidimetric system Bioscreen C. The results demonstrated that strain growth variability increased as the growth conditions became more stressful both in terms of temperature and salinity. The coefficient of variation (CV) of μmax for temperature was larger than that for salinity, indicating that the impact of temperature on strain growth variability was greater than that of salinity. The strains isolated from freshwater aquatic products had more conspicuous growth variations than those from seawater. Moreover, the strains with tlh (+) /tdh (+) /trh (-) exhibited higher growth variability than tlh (+) /tdh (-) /trh (-) or tlh (+) /tdh (-) /trh (+), revealing that gene heterogeneity might have possible relations with the growth variability. This research illustrates that the growth environments, strain sources as well as genotypes have impacts on strain growth variability of V. parahaemolyticus, which can be helpful for incorporating strain variability in predictive microbiology and microbial risk assessment.

The structure of a polysaccharide from Vibrio parahaemolyticus strain AN-16000 has been investigated. The sugar and absolute configuration analysis revealed D-Glc, D-GalN, D-QuiN and L-FucN as major components. The PS was subjected to dephosphorylation with aqueous 40% HF to obtain an oligosaccharide that was analyzed by H-1 and C-13 NMR spectroscopy. The HR-MS spectrum of the oligosaccharide revealed a pentasaccharide composed of two Glc residues, one QuiNAc and one GalNAc, one FucNAc, as well as a glycerol moiety. The structure of the PS was determined using H-1, C-13, N-15 and P-31 NMR spectroscopy; inter-residue correlations were identified by H-1, C-13-heteronuclear multiple-bond correlation, H-1, H-1-NOESY and H-1, P-31-hetero-TOCSY experiments. The PS backbone has the following teichoic acid-like structure: -> 3)-D-Gro-(1-P-6)-beta-D-Glcp-(1 -> 4)-alpha-L-FucpNAc-(1 -> 3)-beta-D-QuipNAc-(1 -> with a side-chain consisting of alpha-D-Glcp-(1 -> 6)-alpha-D-GalpNAc-(1 -> linked to the O3 position of the FucNAc residue.

This paper describes the complete sequence of a novel lytic marine siphophage, VpKK5, that is specific to Vibrio parahemolyticus.

Four new polyketides (1-4) were isolated from the fungus Paecilomyces variotii, which was derived from the jellyfish Nemopilema nomurai. The planar structures and relative configurations of these polyketides were elucidated on the basis of spectroscopic analyses, including 2D NMR experiments. The compounds showed inhibitory activity against pathogenic bacteria including methicillin-resistant Staphylococcus aureus 3089 and multi-drug-resistant Vibrio parahemolyticus 7001 with MIC values in the range 5-40 μg/mL.

Vibrio parahemolyticus Type III effector VopQ is both necessary and sufficient to induce autophagy within one hour of infection. We demonstrated that VopQ interacts with the Vo domain of the conserved vacuolar H(+)-ATPase. Membrane-associated VopQ subsequently forms pores in the membranes of acidic compartments, resulting in immediate release of protons without concomitant release of lumenal protein contents. These studies show how a bacterial pathogen can compromise host ion potentials using a gated pore-forming effector to equilibrate levels of small molecules found in endolysosomal compartments and disrupt cellular processes such as autophagy.

An evaluation of the efficiency of seven enrichment media for Vibrio parahaemolyticus was effected, by means of material collected from the corporeal surface of 82 marine fish caught off the Brazilian coast. On the whole, 45 fish proved positive, from which 71 strains were taken. Among the culture media analyzed the best results were obtained with the new enrichment media represented by two of the nutrient broth (Difco) pH 8.3; one supplemented with 2 g% of NaCl and 500 mg% eosin Y, and another supplemented with 125 mg% metachrome yellow II RD. The combination of enrichment media plus selective-indicator media demonstrated the superiority of the binary association of alcaline broth eosin Y to TCBS agar, both in the number of isolations and serotypes detected.

Recently cases of tissue invasion by as yet unnamed marine vibrios which were morphologically and biochemically similar to both Vibrio parahemolyticus and V. alginolyticus, but not identical with either of them, have been described. We have seen a patient who had serious widespread tissue infection with a halophilic, Gram-negative bacterium which was isolated from blood and leg lesions. The organism had the characteristics of the genus Vibrio, and lactose fermentation and ONPG reactions were positive. It also had a lower tolerance for sodium chloride in the nutrient broth compared with the above two vibrios. The isolate seems identical to the lactose positive (L+) Vibrio described by HOLLIS et al. (1976). Tissue infection resulting in severe necrotizing cellulitis and vasculitis was demonstrated at autopsy.

Bands resembling typical antigen-antibody precipitates developed in Ouchterlony gel diffusion tests between sera from certain individual animals and bacteriologically filtered cultures of Aeromonas salmonicida or Vibrio parahemolyticus. After incubation for several days these bands became coarsely granular and progressively more diffuse. Microsocopic examination revealed them to be made up of massive numbers of what appeared to be microcolonies of barely visible filamentous bacillary forms. All strains of A. salmonicida and V. parahemolyticus tested produced these filterable forms, which were thermolabile but resistant to a number of other physical and chemical agents. Growth of the filterable forms required a particular concentration of serum and medium, which has so far been achieved only by using the Ouchterlony gel diffusion technique. Reversion of these forms to the typical bacillary form has not been observed. No such forms have been detected in cultures of a variety of other fish and human pathogens.

Vibrio parahemolyticus, a major cause of gastroenteritis in Japan, was isolated from white shrimp (Penaeus setiferus). The organism was pathogenic for brown shrimp (Penaeus aztecus) from the Gulf of Mexico.