Antimicrobial Resistance of Escherichia coli isolated in newborn chickens and effect of amoxicillin treatment during its growth

[EN] The use of antimicrobials in food animals is the major determinant for the propagation of resistant bacteria in the animal reservoir. However, other factors also play a part in particular vertical spread between the generations has been suggested to be an important transmission pathway. The objective of this paper was to determine the resistance patterns of Escherichia coli isolated from newly hatched chickens as well as to study the antibiotic pressure effect when amoxicillin was administered during their growing period. With this aim, meconium from 22 day-old Ross chickens was analyzed. In addition, during their growth period, amoxicillin treatments at days 7, 21 and 35 were carried out. Results showed a high number of E. coli resistant strains isolated from one day chickens, being the highest rates for beta-lactams group, followed by quinolone and tetracyclines. After treatment with amoxicillin, the highest percentage of resistances were detected for this antibiotic compared to the others analysed with significant differences in resistance percentages between control and treated broilers detected in relation to ampicillin, cephalothin, streptomycin, kanamycin, gentamicin, chloramphenicol and tetracycline. Differences in resistances to ciprofloxacin and nalidixic acid between control and treated animals were not observed and lack of resistance for amikacin and ceftriaxone. These results suggest the possibility of vertical transmission of resistant strains to newly hatched chickens from parenteral flocks, and seem to indicate that the treatment with amoxicillin increased the resistances of E. coli to other antibiotics.Jiménez Belenguer, AI.; Doménech Antich, EM.; Fenollar-Penadés, A.; Ferrús Pérez, MA.; Villagrá, A. (2016). Antimicrobial Resistance of Escherichia coli isolated in newborn chickens and effect of amoxicillin treatment during its growth. Avian Pathology. 45(4):501-507. doi:10.1080/03079457.2016.1168515S50150745

Helicobacter pylori growth pattern in reference media and extracts from selected minimally processed vegetables

[EN] Helicobacter pylori is an emergent foodborne pathogen of concern, the entrance of which into the food chain has been recently related with the possible contamination of raw or minimally processed vegetables. The present study documented the growth kinetics of the bacterium at 5, 20 and 37 degrees C, in reference media and vegetable substrates, to be fitted to the Gompertz equation. H. pylori was able to grow at 37 degrees C and 20 degrees C, but not at refrigeration temperature. Incubation temperature decrease significantly (p-value < 0.05) affected growth kinetic parameters, with the elongation of lag phase duration (lambda) and the reduction of the maximum specific growth rate (mu(max)) (0.10 log(10)(CFU/ml)/h at 37 degrees C; 0.04 log(10)(CFU/ml)/h at 20 degrees C). In vegetable extracts, the microorganism remained in a viable culturable (VC) form for a maximum of 5 days (20 degrees C), being unable to grow significantly in chard, spinach and in kale. In lettuce, H. pylori achieved growth of close to 1 log(10) cycle (after 5 days at 20 degrees C) (mu(max) 0.79 log(10)(CFU/ml)/d). The present study is the first reporting kinetic parameter values describing the growth behavior of H. pylori at its optimum growth temperature and, also studying the most relevant handling temperatures for minimally processed vegetables: commercial distribution (room temperature 20 degrees C), and refrigeration temperature. (C) 2017 Elsevier Ltd. All rights reserved.The present research work has been supported by the funds provided by the Spanish Ministry of Economy and Competitiveness (MINECO) as HELICOFOOD project with reference AGL2014-53875-R. Postdoctoral contract of M.C. Pina-Perez as Juan de la Cierva-Incorporacion granted by the MINECO is also acknowledged.Pina Pérez, MC.; González Pellicer, A.; Moreno Trigos, MY.; Ferrús Pérez, MA. (2017). Helicobacter pylori growth pattern in reference media and extracts from selected minimally processed vegetables. Food Control. 86:389-396. doi:10.1016/j.foodcont.2017.11.044S3893968

Helicobacter pylori Is Present at Quantifiable Levels in Raw Vegetables in the Mediterranean Area of Spain

Vegetables are one of the main foodstuffs consumed in the Mediterranean diet. However, raw vegetables have been associated with relevant foodborne outbreaks worldwide. Accurate knowledge of the microbiological quantitative risks associated with these matrices is crucial in order to define effective control measures, avoiding the survival and dissemination of foodborne pathogens through the different food chain stages. The aim of the present study is the assessment of the prevalence of Helicobacter pylori (a unique carcinogenic biological agent recognized to date) on leafy vegetables (spinach, lettuce, and chard) by means of the detection of the specific pathogenicity vacA gene. A real-time quantitative polymerase chain reaction (qPCR) optimized approach was used to detect H. pylori-positive samples and the concentration of this pathogen (with a limit of detection equal to 10 cells). One hundred raw vegetable samples were acquired in markets corresponding to the Spanish Mediterranean area. Sliced vegetable leaves were homogenized and centrifuged, and DNA was extracted from the homogenates. qPCR results confirmed 20 out of 100 H. pylori-positive samples, with melting temperature (Tm) values in the range of 84.8&ndash;86.5 &deg;C (TmvacA&nbsp;H. pylori = 85 &deg;C). Amplicons were cut, purified, and sequenced to confirm the homology with the H. pylori vacA gene. A total of 17 out of 100 vegetable samples (12/45 (26.6%) lettuce, 2/21 (9.5%) spinach, and 3/34 (8.8%) chard samples) were finally confirmed as H. pylori-positive. Contamination levels were in the range of 1.5 &plusmn; 0.3 to 2.5 &plusmn; 0.1 log10 cycles (36&ndash;335 CFU/g leafy vegetables). Our results show that H. pylori is detected by qPCR at levels close to infectious doses in fresh vegetables, thus posing a food safety hazard

Caenorhabditis elegans as an in vivo model to assess fucoidan bioactivity preventing Helicobacter pylori infection

Currently, Helicobacter pylori is the unique biological carcinogenic agent. The search for antimicrobial alternatives to antibiotics against this pathogen has been categorized as a priority due to the drastic failure associated with current applied antibiotic therapy. The present study assessed the bioactive antimicrobial capability of fucoidan (“Generally Recognized as Safe” approval – European Commission December 2017) from different species of Phaeophyceae algae (Fucus vesiculosus, Undaria pinnatifida, Macrocystis pyrifera) against H. pylori. All the studied fucoidans showed bacteriostatic and bactericidal effects at the studied concentrations [5–100] μg ml−1 and exposure times [0–7 days]. The most effective anti-H. pylori fucoidan was validated in Caenorhabditis elegans as an in vivo model. C. elegans feed was supplemented with Undaria pinnatifida [0–100] μg ml−1 fucoidan, resulting in a significant improvement in lifespan, lowered H. pylori concentration in the digestive tract, and increased egg-laying pattern. New research lines proposing this compound as an active agent in nutraceutical and preventive novel therapies should be opened.The present research work has been supported by the funds provided by the Spanish Ministry of Economy and Competitiveness (MINECO) under both projects with reference AGL2014-53875-R and AGL2017-86840-C2-2-R. M. C. Pina-Pérez is also grateful to the EC providing a H2020 MSCA – IF Grant Agreement No. 748314.Peer reviewe

Prevalence and Characterization of Beta-Lactam and Carbapenem-Resistant Bacteria Isolated from Organic Fresh Produce Retailed in Eastern Spain

Fresh fruits and vegetables are potential reservoirs for antimicrobial resistance determinants, but few studies have focused specifically on organic vegetables. The present study aimed to determine the presence of third-generation cephalosporin (3GC)- and carbapenem-resistant Gram-negative bacteria on fresh organic vegetables produced in the city of Valencia (Spain). Main expanded spectrum beta-lactamase (ESBL)- and carbapenemase-encoding genes were also detected in the isolates. One hundred and fifteen samples were analyzed using selective media supplemented with cefotaxime and meropenem. Resistance assays for twelve relevant antibiotics in medical use were performed using a disc diffusion test. A total of 161 isolates were tested. Overall, 33.5% presented multidrug resistance and 16.8% were resistant to all β-lactam antibiotics tested. Imipenem resistance was observed in 18% of isolates, and low resistance levels were found to ceftazidime and meropenem. Opportunistic pathogens such as Acinetobacter baumannii, Enterobacter spp., Raoultella sp., and Stenotrophomonas maltophilia were detected, all presenting high rates of resistance. PCR assays revealed blaVIM to be the most frequently isolated ESBL-encoding gene, followed by blaTEM and blaOXA-48. These results confirm the potential of fresh vegetables to act as reservoirs for 3GC- and carbapenem-producing ARB. Further studies must be carried out to determine the impact of raw organic food on the spread of AMRs into the community