Antimicrobial Properties of Glycerol Monolaurate Either Alone or Combined With Selected Organic Acids Against Listeria Monocytogenes.

The objective of this study was to evaluate the antimicrobial properties of glycerol monolaurate (monolaurin) either alone or in combination with organic acids against Listeria monocytogenes in model broth or food. The minimal inhibitory concentration (MIC) of monolaurin was reduced by decreasing the pH value of the medium. The contribution of temperature to monolaurin effectiveness showed that lethal effects of monolaurin increased at higher temperatures and lower pH values, whereas, bacteriostatic effects on growth increased as temperature and pH decreased. The inhibitory effect of ethanol on the growth of L. monocytogenes was slight up to 2.5% ethanol, but was significant in the presence of 5% ethanol. When monolaurin was combined with ethanol, MIC value of the combination was not changed compared to that of the most active single compound alone. MIC value was lower when monolaurin was combined with lactic acid. Synergistic effects were observed when monolaurin was combined with acetic, benzoic, or lactic acid, whereas, there was little interaction when monolaurin was combined with citric acid or ethanol. Planktonic cells exposed to 50 or 100 $\mu$g/ml monolaurin were much more sensitive than were adherent cells, while 1-d adherent cells on stainless steel exposed to 50 or 100 $\mu$g/ml monolaurin were more sensitive than 7-d adherent cells in tryptic soy broth or diluted tryptic soy broth. However, the inactivation effect on those cells significantly increased (P $\u3c$ 0.05) when 50 or 100 $\mu$g/ml monolaurin was combined with 1% acetic acid. Heat effects on planktonic cells, 1-d, or 7-d adherent cells at 55\sp\circC were lower, but inactivation was more enhanced at 65\sp\circC. However, planktonic cells, 1-d, or 7-d adherent cells exposed to 50 or 100 $\mu$g/ml monolaurin at 65\sp\circC were completely inactivated. Air-, vacuum-, or modified atmosphere-package effects combined with 200 $\mu$g/ml monolaurin or 0.5% lactic acid on crawfish tail meat inoculated with 10\sp3 cells/g of L. monocytogenes at 4\sp\circC were not different (P $\u3e$ 0.05) compared with controls. However, each package containing crawfish tail meat treated with 200 $\mu$g/g monolaurin combined with 0.5% lactic acid significantly enhanced (P $\u3c$ 0.05) the inhibitory effect. Results indicate that 200 $\mu$g/ml monolaurin, 0.5% lactic acid, and MAP had the greatest potential to inhibit growth of the bacterium

RESPONSE SURFACE MODELING OF LISTERIA MONOCYTOGENES INACTIVATION ON LETTUCE TREATED WITH ELECTROLYZED OXIDIZING WATER

ABSTRACT Electrolyzed oxidizing water has been estimated that it has strong bactericidal activity and has been widely used as a disinfectant for inactivating PRACTICAL APPLICATIONS Electrolyzed oxidizing water is an important sanitizer, and nowadays it has been widely used in food industry. Lettuce is regarded as a "healthier" 3 Correspondin

Dokaz protutijela protiv velikog metilja Fasciola hepatica u goveda na otoku Ulleung, Koreja.

We performed a cross-sectional study to estimate the seroprevalence of Fasciola hepatica in herds of cattle on Ulleung island, Korea. Blood samples were collected from randomly selected cattle and the sera were separated and analysed with an ELISA to detect antibodies against F. hepatica. The positive samples were classified as mildly, moderately or strongly positive. Out of 405 cattle sera assessed, 38 (9.4%) were seropositive for antibodies against F. hepatica. From these, 2.5% each were moderately or strongly positive and 4.4% were mildly positive. A significantly higher seroprevalence (P<0.05) was observed in young animals (<2 y old, 15.3%) compared to adults (≥2 y old, 5.4%), while no significant difference in seropositivity was found between male and female animals. This is the the first report of F. hepatica seroprevalence in cattle herds in Korea. These findings may be used to establish a base-line of information for future investigations focused on the significance of F. hepatica in Korea.Provedeno je presječno istraživanje radi procjene seroprevalencije invadiranosti velikim metiljem Fasciola hepatica u stadima goveda na otoku Ulleung u Koreji. Uzorci krvi bili su uzeti od nasumce odabranih goveda, a odvojeni uzorci seruma bili su pretraženi imunoenzimnim testom na prisutnost protutijela specifičnih za velikog metilja. Pozitivni uzorci bili su svrstani u skupine: slabo, umjereno i jako pozitivni. Od 405 pretraženih uzoraka seruma, 38 (9,4%) je bilo pozitivnih na protutijela specifična za metilj F. hepatica. Od toga je 2,5% uzoraka bilo umjereno ili jako pozitivno, a 4,4% slabo pozitivno. Značajno veća seroprevalencija (P<0,05) ustanovljena je u mladih životinja (u dobi manjoj od dvije godine, 15,3%) u usporedbi s odraslima (≥2 godine, 5,4%), dok nije ustanovljena značajna razlika u seropozitivnosti između mužjaka i ženki. Ovo je prvo izvješće o seroprevalenciji velikog metilja u stadima goveda u Koreji. Nalazi mogu biti od koristi za buduća istraživanja o značenju velikog metilja F. hepatica u Koreji

Dokaz protutijela protiv velikog metilja Fasciola hepatica u goveda na otoku Ulleung, Koreja.

We performed a cross-sectional study to estimate the seroprevalence of Fasciola hepatica in herds of cattle on Ulleung island, Korea. Blood samples were collected from randomly selected cattle and the sera were separated and analysed with an ELISA to detect antibodies against F. hepatica. The positive samples were classified as mildly, moderately or strongly positive. Out of 405 cattle sera assessed, 38 (9.4%) were seropositive for antibodies against F. hepatica. From these, 2.5% each were moderately or strongly positive and 4.4% were mildly positive. A significantly higher seroprevalence (P<0.05) was observed in young animals (<2 y old, 15.3%) compared to adults (≥2 y old, 5.4%), while no significant difference in seropositivity was found between male and female animals. This is the the first report of F. hepatica seroprevalence in cattle herds in Korea. These findings may be used to establish a base-line of information for future investigations focused on the significance of F. hepatica in Korea.Provedeno je presječno istraživanje radi procjene seroprevalencije invadiranosti velikim metiljem Fasciola hepatica u stadima goveda na otoku Ulleung u Koreji. Uzorci krvi bili su uzeti od nasumce odabranih goveda, a odvojeni uzorci seruma bili su pretraženi imunoenzimnim testom na prisutnost protutijela specifičnih za velikog metilja. Pozitivni uzorci bili su svrstani u skupine: slabo, umjereno i jako pozitivni. Od 405 pretraženih uzoraka seruma, 38 (9,4%) je bilo pozitivnih na protutijela specifična za metilj F. hepatica. Od toga je 2,5% uzoraka bilo umjereno ili jako pozitivno, a 4,4% slabo pozitivno. Značajno veća seroprevalencija (P<0,05) ustanovljena je u mladih životinja (u dobi manjoj od dvije godine, 15,3%) u usporedbi s odraslima (≥2 godine, 5,4%), dok nije ustanovljena značajna razlika u seropozitivnosti između mužjaka i ženki. Ovo je prvo izvješće o seroprevalenciji velikog metilja u stadima goveda u Koreji. Nalazi mogu biti od koristi za buduća istraživanja o značenju velikog metilja F. hepatica u Koreji

Differentiation of Bacillus thuringiensis From Bacilluscereus Group Using a Unique Marker Based on Real-Time PCR

The efficiency of a novel biomarker (the transcriptional regulator, XRE) was tested and evaluated in differentiating Bacillus thuringiensis from Bacillus cereus group species in environmental and spiked samples based on PCR and real-time PCR. Totally 120 strains, representing two bacterial groups, B. cereus group and non-Bacillus sp., were used to evaluate the performance of XRE and crystal protein (cry2, an existing biomarker). Further, three diverse samples (kimbap, lettuce, and spinach) were inoculated with B. thuringiensis and prominent biomarkers XRE and cry2 were used as targets. Direct analysis of the detection results for the pure cultures of B. cereus group wild-types, references and type strains revealed an accuracy rate of 97.5% targeting XRE, and 83.3% targeting cry2. The real-time PCR was constructed with a R2-value of 0.993. For the artificially contaminated samples, a concentration of 103 CFU/g of B. thuringiensis in spiked food samples could be detected using real-time PCR targeting XRE. A good performance was obtained with XRE in discriminating B. thuringiensis from B. cereus groups, as well as detecting B. thuringiensis in spiked food samples with PCR or real-time PCR. Therefore, this real-time PCR targeting XRE can be used as a dependable and promising tool to identify B. thuringiensis in foods

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

Molecular Detection of Antibiotic Resistance Genes in Shiga Toxin-Producing E. coli Isolated from Different Sources

Shiga toxin-producing Escherichia coli (STEC) is an enteric pathogen associated with human gastroenteritis outbreaks. Extensive use of antibiotics in agriculture selects resistant bacteria that may enter the food chain and potentially causes foodborne illnesses in humans that are less likely to respond to treatment with conventional antibiotics. Due to the importance of antibiotic resistance, this study aimed to investigate the combination of phenotypic and genotypic antibiotic resistance in STEC isolates belonging to serogroups O26, O45, O103, O104, O111, O121, O145, and O157 using disc diffusion and polymerase chain reaction (PCR), respectively. All strains were phenotypically resistant to at least one antibiotic, with 100% resistance to erythromycin, followed by gentamicin (98%), streptomycin (82%), kanamycin (76%), and ampicillin (72%). The distribution of antibiotic resistance genes (ARGs) in the STEC strains was ampC (47%), aadA1 (70%), ere(A) (88%), blaSHV (19%), blaCMY (27%), aac(3)-I (90%), and tet(A) (35%), respectively. The results suggest that most of the strains were multidrug-resistant (MDR) and the most often observed resistant pattern was of aadA1, ere(A), and aac(3)-I genes. These findings indicate the significance of monitoring the prevalence of MDR in both animals and humans around the globe. Hence, with a better understanding of antibiotic genotypes and phenotypes among the diverse STEC strains obtained, this study could guide the administration of antimicrobial drugs in STEC infections when necessary

Virulence Characteristics and Antibiotic Resistance Profiles of Shiga Toxin-Producing Escherichia coli Isolates from Diverse Sources

Shiga toxin-producing Escherichia coli (STEC) is an enteric pathogen that causes several gastrointestinal ailments in humans across the world. STEC&rsquo;s ability to cause ailment is attributed to the presence of a broad range of known and putative virulence factors (VFs) including those that encode Shiga toxins. A total of 51 E. coli strains belonging to serogroups O26, O45, O103, O104, O113, O121, O145, and O157 were tested for the presence of nine VFs via PCR and for their susceptibility to 17 frequently used antibiotics using the disc diffusion method. The isolates belonged to eight different serotypes, including eight O serogroups and 12 H types. The frequency of the presence of key VFs were stx1 (76.47%), stx2 (86.27%), eae (100%), ehxA (98.03%), nleA (100%), ureC (94.11%), iha (96.07%), subA (9.80%), and saa (94.11%) in the E. coli strains. All E. coli strains carried seven or more distinct VFs and, among these, four isolates harbored all tested VFs. In addition, all E. coli strains had a high degree of antibiotic resistance and were multidrug resistant (MDR). These results show a high incidence frequency of VFs and heterogeneity of VFs and MDR profiles of E. coli strains. Moreover, half of the E. coli isolates (74.5%) were resistant to &gt; 9 classes of antibiotics (more than 50% of the tested antibiotics). Thus, our findings highlight the importance of appropriate epidemiological and microbiological surveillance and control measures to prevent STEC disease in humans worldwide