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1.
Ital J Food Saf ; 13(1): 12053, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38577580

RESUMEN

Campylobacteriosis is the most reported foodborne disease in the European Union, with more than 100,000 confirmed cases annually. Human infection can be caused by a low infectious dose, and in fragile populations, the food disease can manifest itself in acute and severe forms. This study aims to analyze two cases of campylobacteriosis in fragile people caused by Campylobacter jejuni in 2023 in Tuscany and the actions of the Local Health Competent Authority. From the results of the related investigations, it was possible to attribute both cases of foodborne diseases to unsafe food management during preparation/administration. Given the peculiar characteristics of the etiological agent, it is necessary to focus the attention of the population, especially those who deal with fragile subjects, on the good hygiene practices to be followed both at home and in collective catering.

2.
Food Res Int ; 184: 114268, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38609245

RESUMEN

Insects intended for human consumption are considered Novel Foods according to EU legislation. marketed in form of powders, bars, snacks are increasingly available on the EU market, especially on e-commerce. The commercial form and the way of distribution make IBPs particularly prone to mislabeling. Literature concerning the mislabeling occurrence in IBPs is extremely scarce. In this study, 46 processed IBPs were collected on nine EU e-commerce platforms (e-CO) to be authenticated by metabarcoding. A 200 bp region from 16S rRNA gene was used as molecular target. Sequencing data were processed using DADA2 R package, and sequences were taxonomically assigned through BLAST analysis against GenBank. Procedural blanks and positive controls were included in the analysis, and threshold values were established to filter the final data. The mislabeling rate (i. e. the mismatch between the species declared on the IBP label and the species identified by metabarcoding) was calculated. Overall, a high mislabeling rate (33.3 %) was observed, although this percentage is influenced by the e-CO platform and the insect species, with A. domesticus particularly involved. The use of species not listed in authorized Novel Food (e. g. Gryllus locorojo), and/or the partial replacement of high value species with lower value species was highlighted for the first time in processed IBPs. The presence of insect pests was also detected. Metabarcoding was confirmed as an effective tool for IBPs authentication. Also, outcomes from this study can provide useful data on the main issues involving the EU IBPs' market, that can represent an incentive to reinforce both official controls and FBO's self-controls on these poorly investigated products.


Asunto(s)
Agammaglobulinemia , Humanos , Animales , ARN Ribosómico 16S/genética , Comercio , Insectos , Bocadillos
3.
Ital J Food Saf ; 12(1): 11012, 2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-37064518

RESUMEN

The Commission Regulation (EU) No. 2021/382 (European Commission, 2021), amending the Regulation (EC) No. 852/2004 (European Commission, 2004), introduced the obligation for companies to establish and maintain a food safety culture (FSC). The methodology to evaluate, implement, and enhance the level of FSC is up to the individual companies. This study aimed to investigate the perception of FSC among the employees of 3 Tuscan medium-sized enterprises in the food sector, producing cured meat (A), dairy products (B), and frozen fish products (C). The survey was conducted through the development and administration of a questionnaire based on a 5 points Likert scale, referring to different aspects of FSC, organized in 6 sections with 5-6 statements each and subjected to a percentage of employees between 76 and 85%, classified also by the length of service (≤3 and >3 years). For all the companies, the minimum median and mode value for scores obtained by the different sections was 4, and the minimum median and mode value for the single statement was 3 (A, B; except for a bimodal value 2-4) and 4 (C). The section awareness and perception of risk showed the highest mean scores in all companies. As for the length of service, senior employees gave lower scores than junior ones in all sections in B and 3 sections in C. Overall, the results of the questionnaires showed a good perception of FSC, even though it was possible to identify some partial weaknesses.

4.
Ital J Food Saf ; 11(1): 10039, 2022 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-35284338

RESUMEN

The activity of manuka (Leptospermum scoparium) essential oil (EO) on biofilms of foodborne Listeria monocytogenes and Staphylococcus aureus has been studied. Seven strains of L. monocytogenes and 7 of S. aureus (5 methicillin-resistant) were tested. EO minimal inhibitory concentration (MIC), EO minimal bactericidal concentration (MBC) and biofilm production quantification were determined for each strain by microtiter methods. Moreover, EO Minimum Biofilm Inhibitory Concentration (MBIC) and Minimum Biofilm Eradicating Concentration (MBEC) were determined on 2 L. monocytogenes and 3 S. aureus that showed the best biofilm production. Finally, on 4 strains out of 5 (2 L. monocytogenes and 2 S. aureus) EO Biofilm Reduction Percentage (BRP) vs. untreated controls was assessed after a treatment with EO subinhibitory concentrations. The chemical composition of manuka essential oil was determined by Gas Chromatography- Electron Impact Mass Spectrometry (GCEIMS). The manuka EO demonstrated good antimicrobial activity: L. monocytogenes MIC and MBC were 0.466 mg/ml and 0.933 mg/ml, respectively, whereas S. aureus MIC and MBC were 0.233 mg/ml and 0.466 mg/ml, respectively. Furthermore, L. monocytogenes showed a MBIC of 0.933 mg/ml and a MBEC in the range of 0.933-1.865 mg/ml, whereas S. aureus had a MBIC in the range of 7.461-14.922 mg/ml and a MBEC of 14.922 mg/ml. L. monocytogenes revealed no significant BRP after the treatment with manuka EO, whereas S. aureus showed a BRP higher than 50% with MIC/2 and MIC/4 EO concentrations. These results provide information for feasible manuka EO applications in food production systems.

5.
Front Cell Infect Microbiol ; 10: 592512, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33178635

RESUMEN

The present study investigated the genomic constitution and antimicrobial resistance (AMR) of 238 Campylobacter from pigs and wild boars in Italy between 2012 and 2019. Campylobacter strains were genotyped using multilocus sequence typing (MLST) and whole genome MLST (wgMLST), screened for antimicrobial resistance genes, and tested for phenotypic susceptibility to six different antibiotics. C. coli was detected in 98.31% and 91.66% of pigs and wild boars, while C. jejuni was isolated in the remaining cases. MLST assigned 73 STs and 13 STs in pigs and wild boars, respectively, including 44 novel STs. The predominant ST in pigs was ST-854 (12.36%), followed by ST-9264 (6.18%). ST-1055 and ST-1417 were predominant in wild boars (30% and 13.33%, respectively). The minimum spanning tree using 1,121 global MLST profiles showed specific Italian clusters and a clear separation between pig and wild boar profiles. The wgMLST confirmed the MLST clustering and revealed a high genetic diversity within C. coli population in Italy. Minimum inhibitory concentrations (MIC) of six antibiotics revealed higher resistance in pigs to ciprofloxacin, nalidixic acid, streptomycin and tetracycline, compared to wild boar. In contrast, most strains were susceptible to gentamicin. Worrying levels of multidrug resistance (MDR) were observed mostly in pig isolates. Molecular screening of AMR mechanisms revealed the predominance of gyrA T86I substitution among fluoroquinolone- and quinolone-resistant isolates, and the 23S rRNA A2075G mutation among macrolide-resistant isolates. Other resistance determinants were observed: (i) tet(O) gene was present among tetracycline-resistant isolates; (ii) rpsL and aph(3')-III genes conferring resistance to aminoglycosides, were identified only in streptomycin or gentamicin-resistant pig isolates; (iii) cmeA, cmeB, cmeC, cmeR genes responsible of pump efflux mechanisms, were observed in almost all the strains; (iv) OXA-61, encoding ß-lactamase, was found in the half of the strains. Genotypic and phenotypic AMR profiling was fairly correlated for quinolones/fluoroquinolones. Campylobacter infection is common also in wild boar populations in Italy, suggesting that wild boars could be a reservoir of resistant and multi-resistant Campylobacter species, which may be of public health concern. The present study adds to our knowledge on the epidemiological and ecological traits of this pathogen in domesticated and wild swine.


Asunto(s)
Infecciones por Campylobacter , Campylobacter coli , Campylobacter jejuni , Animales , Antibacterianos/farmacología , Infecciones por Campylobacter/veterinaria , Campylobacter coli/genética , Campylobacter jejuni/genética , Farmacorresistencia Bacteriana , Genotipo , Italia/epidemiología , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias Multilocus , Sus scrofa , Porcinos
6.
Foods ; 9(8)2020 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-32751777

RESUMEN

The aim of the research study was to evaluate the effects of a common culinary spice such as garlic powder and salt addition on the quality and microbial shelf life of rabbit meat burgers. Rabbit burgers were evaluated for pH, the colour parameters, the water holding capacity and microbial loads during storage time of seven days at 4 °C. Four different formulations of burgers (n = 180 in total) were tested as control samples (only meat, C), burgers with garlic powder (at 0.25%, G), burgers with salt (at 1.00%, S) and burgers with both garlic powder and salt (0.25% and 1.00%, respectively, GS). As results, it was highlighted that garlic powder and salt addition significant affected pH, water holding capacity and some colour parameters of burgers. In particular, salt affected the pH of the raw burgers, leading to lower values that partially influenced all the colour parameters with higher a* values of S burgers. The mix of garlic powder and salt (GS burgers) showed mixed effects even if more closed to the G burgers than S ones. Salt expressed its properties of binding water molecules reducing drip and cooking losses in S and GS burgers. No variations in microbial loads were highlighted in relation to the formulations. Storage time affected all the parameters, highlighting a deterioration of the burgers' quality and an increase of the microbial loads.

7.
Meat Sci ; 169: 108226, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32599418

RESUMEN

Rabbit burgers were evaluated for fatty acids profile, oxidative status, antioxidant potential and sensory during storage time of seven days at 4 °C. The aim of the research study was to evaluate if a common culinary spice as garlic could overcome the controversy effects of salt (mostly related to a pro-oxidant effect). Therefore, four formulations were made: only meat (control, C) meat added with garlic powder at 0.25% (G), meat added with salt at 1.00% (S) and meat added with garlic powder (0.25%) and salt (1.00%) (GS). As results, it was highlighted that garlic powder was not capable to reduce significantly the negative effect related to the salt addition. Salt induced different modifications to burgers leading to a more liked product due to its properties to enhance sensory characteristics, on the other hand, induced different oxidation processes that could decrease the nutritional value. Further studies are needed to better elucidate if different garlic products/concentrations could apport higher beneficial effects.


Asunto(s)
Ácidos Grasos/análisis , Ajo , Productos de la Carne/análisis , Cloruro de Sodio/química , Animales , Antioxidantes/análisis , Culinaria , Almacenamiento de Alimentos , Humanos , Odorantes , Oxidación-Reducción , Polvos , Conejos , Gusto
8.
Animals (Basel) ; 10(4)2020 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-32344604

RESUMEN

Wild boar are among the most widespread wild mammals in Europe. Although this species can act as a reservoir for different pathogens, data about its role as a carrier of pathogenic and antimicrobial-resistant Escherichia coli are still scarce. The aim of this study was to evaluate the occurrence of antimicrobial-resistant and pathogenic Escherichia coli in wild boar in the Tuscany region of Italy. During the hunting season of 2018-2019, E. coli was isolated from 175 of 200 animals and subjected to antimicrobial resistance tests and PCR for detection of resistance and virulence factor genes. The highest resistance rates were against cephalothin (94.3%), amoxicillin-clavulanic acid (87.4%), ampicillin (68.6%), and tetracycline (44.6%). The most detected resistance genes were blaCMY-2 (54.3%), sul1 (38.9%), sul2 (30.9%), and tetG (24.6%). Concerning genes encoding virulence factors, 55 of 175 isolates (31.4%) were negative for all tested genes. The most detected genes were hlyA (47.4%), astA (29.1%), stx2 (24.6%), eaeA (17.1%), and stx1 (11.4%). E. coli was classified as Shiga toxin-producing E. coli (STEC) (21.7%), enterohemorrhagic E. coli (EHEC) (6.3%), enteroaggregative E. coli (EAEC) (5.1%), and atypical enteropathogenic E. coli (aEPEC) (3.4%). Enterotoxigenic E. coli (ETEC), enteroinvasive E. coli (EIEC), and typical enteropathogenic E. coli (tEPEC) were not detected. Our results show that wild boars could carry pathogenic and antimicrobial-resistant E. coli, representing a possible reservoir of domestic animal and human pathogens.

9.
Microorganisms ; 8(2)2020 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-32046038

RESUMEN

Campylobacter spp. are among the microorganisms most commonly associated with foodborne disease. Swine are known to be the main reservoir of Campylobacter coli and a possible source infection of humans as a result of carcass contamination at slaughter. The aim of this study was to evaluate the prevalence of C. coli contamination in swine carcasses, the antimicrobial resistance (AMR) patterns of isolates and the genetic diversity between strains obtained from swine and those isolated from humans. The prevalence of contamination was higher on carcasses (50.4%) than in faeces (32.9%). The 162 C. coli isolated from swine were examined by pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST). The results of PFGE indicated a high genetic diversity among the isolates, with 25 different PFGE types. MLST assigned 51 sequence types (STs) to isolates. The most common genotype was ST-854 (16.04%), ST-9264 (10.49 %) and ST-1016 (6.08 %). Results of AMR showed a high resistance to quinolones and fluoroquinolones together with aminoglycosides and tetracycline. Many strains were multi-resistant with predominant R-type TeSCipNa (57%). Five resistance genes were detected along with mutation in the gyrA gene. A strong correlation between phenotypic and genotypic resistance was found for fluoroquinolone and tetracycline. Genetic profiles obtained in swine isolates were compared to those of 11 human strains. All human strains and 64.19% of animal strains (104/162) were assigned to the ST-828 clonal complex.

10.
PLoS One ; 14(12): e0225957, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31809529

RESUMEN

Campylobacter species are common foodborne pathogens associated with cases of human gastroenteritis worldwide. A detailed understanding of the prevalence, contamination levels and molecular characteristics of Campylobacter spp. in cattle and chicken, which are likely the most important sources of human contamination, is imperative. A collection of 1243 poultry meat samples (665 chicken breasts and 578 chicken thighs) and 1203 bovine meat samples (689 hamburgers and 514 knife-cut meat preparations) were collected at retail outlets, in randomly selected supermarkets located in different Italian regions during one year. Of these samples, 17.38% of the poultry meat and 0.58% of the bovine meat samples tested positive for Campylobacter, of which 131 were Campylobacter jejuni (57.96%) and 95 were Campylobacter coli (42.03%). Campylobacter isolates were genotyped with the aim of assessing the genetic diversity, population structure, source distribution and Campylobacter transmission route to humans. All isolates were molecularly characterized by pulse field gel electrophoresis (PFGE), and further genotyped using multilocus sequence typing (MLST) and fla-SVR sequencing to gain better insight into the population structure. Antibiotic resistance was also investigate. The highest levels of resistance among chicken strains were observed for ciprofloxacin (88.25%), nalidixic acid (81.45%) and tetracycline (75.6%). PFGE analysis revealed 73 pulsotypes for C. jejuni and 54 pulsotypes for C. coli, demonstrating the existance of different and specific clones circulating in Italy. MLST of C.jejuni isolates mainly clustered in the CC353, CC354, CC21, CC206 and CC443; while C.coli isolates clustered only in CC828. The most common flaA alleles were 287 for C. jejuni and 66 for C. coli. Our study confirms that poultry meat is the main source of Campylobacteriosis, whereas red meat had a low level of contamination suggesting a minor role in transmission. The high presence of Campylobacter in retail chicken meat, paired with its increased resistance to antimicrobials with several multidrug resistance profiles detected, is alarming and represents a persistent threat to public health.


Asunto(s)
Campylobacter , Pollos , Contaminación de Alimentos , Microbiología de Alimentos , Carne/microbiología , Animales , Antibacterianos/farmacología , Campylobacter/clasificación , Campylobacter/efectos de los fármacos , Campylobacter/aislamiento & purificación , Bovinos , Electroforesis en Gel de Campo Pulsado , Contaminación de Alimentos/estadística & datos numéricos , Microbiología de Alimentos/estadística & datos numéricos , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias Multilocus , Fenotipo , Prevalencia
12.
PLoS One ; 14(10): e0223804, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31603950

RESUMEN

Campylobacter jejuni, a common foodborne zoonotic pathogen, causes gastroenteritis worldwide and is increasingly resistant to antibiotics. We aimed to investigate the antimicrobial resistance (AMR) genotypes of C. jejuni isolated from humans, poultry and birds from wild and urban Italian habitats to identify correlations between phenotypic and genotypic AMR in the isolates. Altogether, 644 C. jejuni isolates from humans (51), poultry (526) and wild- and urban-habitat birds (67) were analysed. The resistance phenotypes of the isolates were determined using the microdilution method with EUCAST breakpoints, and AMR-associated genes and single nucleotide polymorphisms were obtained from a publicly available database. Antimicrobial susceptibility testing showed that C. jejuni isolates from poultry and humans were highly resistant to ciprofloxacin (85.55% and 76.47%, respectively), nalidixic acid (75.48% and 74.51%, respectively) and tetracycline (67.87% and 49.02%, respectively). Fewer isolates from the wild- and urban-habitat birds were resistant to tetracycline (19.40%), fluoroquinolones (13.43%), and quinolone and streptomycin (10.45%). We retrieved seven AMR genes (tet (O), cmeA, cmeB, cmeC, cmeR, blaOXA-61 and blaOXA-184) and gyrA-associated point mutations. Two major B-lactam genes called blaOXA-61 and blaOXA-184 were prevalent at 62.93% and 82.08% in the poultry and the other bird groups, respectively. Strong correlations between genotypic and phenotypic resistance were found for fluoroquinolones and tetracycline. Compared with the farmed chickens, the incidence of AMR in the C. jejuni isolates from the other bird groups was low, confirming that the food-production birds are much more exposed to antimicrobials. The improper and overuse of antibiotics in the human population and in animal husbandry has resulted in an increase in antibiotic-resistant infections, particularly fluoroquinolone resistant ones. Better understanding of the AMR mechanisms in C. jejuni is necessary to develop new strategies for improving AMR programs and provide the most appropriate therapies to human and veterinary populations.


Asunto(s)
Antibacterianos/farmacología , Aves/microbiología , Campylobacter jejuni/genética , Farmacorresistencia Bacteriana , beta-Lactamasas/genética , Animales , Animales Salvajes/microbiología , Proteínas Bacterianas/genética , Campylobacter jejuni/efectos de los fármacos , Campylobacter jejuni/aislamiento & purificación , Ciprofloxacina/farmacología , Humanos , Italia , Ácido Nalidíxico/farmacología , Aves de Corral/microbiología , Especificidad de la Especie , Tetraciclina/farmacología , Remodelación Urbana
13.
Foods ; 8(7)2019 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-31331106

RESUMEN

This study provides a framework of the factors predicting the intention of eating an insect-based product. As part of the study, a seminar was carried out to explore how the provision of information about ecological, health, and gastronomic aspects of entomophagy would modify consumer beliefs regarding insects as food. Before and after the informative seminar, two questionnaires about sociodemographic attributes and beliefs about the consumption of insects as food were given. Participants were then asked to carry out a sensory evaluation of two identical bread samples, but one was claimed to be supplemented with insect powder. Results showed that perceived behavioral control is the main predictor of the intention, followed by neophobia and personal insect food rejection. The disgust factor significantly decreased after the participants attended the informative seminar. Sensory scores highlighted that participants gave "insect-labelled" samples higher scores for flavor, texture, and overall liking, nevertheless, participants indicated that they were less likely to use the "insect-labelled" bread in the future. Our findings provide a better understanding of insect food rejection behavior and help to predict the willingness to try insect-based products based on some important individual traits and information.

14.
PLoS One ; 14(3): e0213689, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30901346

RESUMEN

Brucellosis is a major public health problem still prevalent as a neglected endemic zoonosis requiring proactive attention in many communities worldwide. The present study involved analysis of Brucella field strains submitted for typing to the Italian National Reference Laboratory for Brucellosis from 2007 to 2015. Strains were identified at the species and biovar levels by classic and molecular techniques according to the World Organisation for Animal Health Manual. In total, 5,784 strains were typed: 3,089 Brucella abortus (53.4%), 2,497 B. melitensis (43.2%), 10 B. ovis (0.2%), 181 B. suis (3.1%), and 7 B. ceti (0.1%). The 2,981 strains from cattle were typed as B. abortus biovars 1, 3, and 6 (90.1%) and B. melitensis biovar 3 (9.9%). The 318 strains from water buffalo were typed as B. abortus biovars 1, 3 (95.9%) and B. melitensis biovar 3 (4.1%). The 2,279 strains from sheep and goats were typed as B. abortus biovars 1 and 3 (4.3%); B. melitensis biovars 1, 3, (95.3%); and B. ovis (0.4%). The 173 strains from wild boar were typed as B. suis biovar 2 (98.3%) and B. melitensis biovar 3 (1.7%). The 11 strains from pigs were typed as B. suis biovar 2. The 13 strains from humans were typed as B. melitensis biovar 3. The two strains from horses were typed as B. abortus biovar 1, while the seven strains from dolphins were typed as B. ceti. This additional knowledge on the epidemiology of brucellosis in Italy may be useful to formulate policies and strategies for the control and eradication of the disease in animal populations. The animal species affected, biovars typed, geographical origins, and spatial distributions of isolates are herein analyzed and discussed.


Asunto(s)
Brucella/clasificación , Brucelosis/epidemiología , Brucelosis/veterinaria , Animales , Animales Salvajes/microbiología , Técnicas de Tipificación Bacteriana , Brucelosis/diagnóstico , ADN Bacteriano/análisis , Geografía , Humanos , Italia/epidemiología , Ganado/microbiología , Tipificación Molecular , Reacción en Cadena de la Polimerasa , Zoonosis/diagnóstico , Zoonosis/epidemiología , Zoonosis/microbiología
15.
Ital J Food Saf ; 8(4): 8036, 2019 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-31897395

RESUMEN

Propolis antimicrobial activity has been limitedly studied in food, particularly in dairy products. We studied the antimicrobial activity of an alcoholic extract of an Italian propolis in sterile skim milk, pasteurized cow's milk, and cow's and goat's whey cheese (ricotta). Following the determination of the minimal inhibitory concentration on Gram+ and Gram- bacteria, the extract was employed at 2 and 5% (P2, P5), using controls with the same ethanol concentrations (E2, E5) and without any addition. In milk trials, Listeria monocytogenes, Staphylococcus aureus, Bacillus cereus, and Pseudomonas fluorescens were tested. P2 and P5 samples registered significant decreases of Gram+ bacteria in skim milk. The same was true for P5 in cows' milk, but only with S. aureus for P2. Ricotta was inoculated with L. monocytogenes, S. aureus and B. cereus and stored at 8.5°C. In cow's milk ricotta, L. monocytogenes counts in P5 were always lower than control during the storage time, significantly so from the 14th day. In goat's ricotta, L. monocytogenes counts in P5 were at least one logarithm lower than E5, whereas the extract didn't show a significant effect on S. aureus and B. cereus. The antimicrobial activity of propolis, particularly on L. monocytogenes, could be employed in ready-to-eat refrigerated dairy products.

16.
Electrophoresis ; 39(16): 2160-2167, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29761912

RESUMEN

American foulbrood disease (AFB) is the main devastating disease that affects honeybees' brood, caused by Paenibacillus larvae. The trend of the research on AFB has addressed the mechanisms by which P. larvae bacteria kill honeybee larvae. Since prepupae could react to the infection of AFB by increasing protease synthesis, the aim of this work was to compare protease activity in worker prepupae belonging to healthy colonies and to colonies affected by AFB. This investigation was performed by zymography. In gel, proteolytic activity was observed in prepupae extracts belonging only to the healthy colonies. In the prepupae extracts, 2D zimography followed by protein identification by MS allowed to detect Trypsin-1 and Chymotrypsin-1, which were not observed in diseased specimens. Further investigations are needed to clarify the involvement of these proteinases in the immune response of honeybee larvae and the mechanisms by which P. larvae inhibits protease production in its host.


Asunto(s)
Abejas/enzimología , Electroforesis/métodos , Péptido Hidrolasas/análisis , Animales , Abejas/microbiología , Quimotripsina/análisis , Interacciones Microbiota-Huesped , Larva/enzimología , Larva/inmunología , Larva/microbiología , Paenibacillus larvae/patogenicidad , Pupa/enzimología , Tripsina/análisis
17.
J Food Sci ; 82(10): 2364-2370, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28892140

RESUMEN

The capability to produce biofilm is an important persistence and dissemination mechanism of some foodborne bacteria. This paper investigates the relationship between some molecular characteristics (SCCmec, ST, spa-type, agr-type, cna, sarA, icaA, icaD, clfA, fnbA, fnbB, hla, hlb) of 22 food-related methicillin-resistant Staphylococcus aureus (MRSA) strains and their ability to form biofilm on stainless steel and polystyrene. Five (22.7%, 5/22) strains were able to synthesize biofilm on polystyrene, and one of these (4.5%, 1/22) strains was also able to synthesize biofilm on stainless steel. The largest amount of biofilm was formed on polystyrene by 2 MRSA strains isolated from cows' milk, thus raising concern about the dairy industry. The majority of MRSA biofilm producers carried SCCmec type IVa, suggesting that the presence of SCCmecIVa and/or agr type III could be related to the ability to form biofilm. In conclusion, in order to achieve an acceptable level of food safety, Good Hygiene Practices should be strictly implemented along the food chain to reduce the risk of colonization and dissemination of MRSA biofilm-producing strains in the food industry. PRACTICAL APPLICATION: In this study, some assayed isolates of food-related MRSA demonstrated the capacity to form biofilm. Biofilm formation differed according to surface characteristics and MRSA strains. A relationship was observed between some molecular characteristics and the ability to form biofilms. Few studies have investigated the ability of MRSA to form biofilms, and the majority of these studies have investigated clinical aspects. This work was performed to investigate whether or not there is a difference between MRSA food isolates and MRSA clinical isolates in their ability to form biofilm. These initial findings could provide information that will contribute to a better understanding of these aspects.


Asunto(s)
Biopelículas , Staphylococcus aureus Resistente a Meticilina/fisiología , Leche/microbiología , Infecciones Estafilocócicas/microbiología , Animales , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Biopelículas/efectos de los fármacos , Bovinos , Femenino , Humanos , Meticilina/farmacología , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación
18.
Int J Food Microbiol ; 256: 54-61, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-28599175

RESUMEN

Donkey milk is recently gaining attention due to its nutraceutical properties. Its low casein content does not allow caseification, so the production of a fermented milk would represent an alternative way to increase donkey milk shelf life. The aim of this study was to investigate the possibility of employing selected Streptococcus thermophilus and Lactobacillus plantarum isolates for the production of a novel donkey milk fermented beverage. Lysozyme resistance and the ability to acidify donkey milk were chosen as main selection parameters. Different fermented beverages (C1-C9) were produced, each with a specific combination of isolates, and stored at refrigerated conditions for 35days. The pH values and viability of the isolates were weekly assessed. In addition, sensory analysis was performed. Both S. thermophilus and L.plantarum showed a high degree of resistance to lysozyme with a Minimum Bactericidal Concentration>6.4mg/mL for 100% of S. thermophilus and 96% of L. plantarum. S. thermophilus and L. plantarum showed the ability to acidify donkey milk in 24h at 37°C, with an average ΔpH value of 2.91±0.16 and 1.78±0.66, respectively. Four L. plantarum and two S. thermophilus were chosen for the production of fermented milks. Those containing the association S. thermophilus/L. plantarum (C1-C4) reached a pH lower than 4.5 after 18h of fermentation and showed microbial loads higher than 7.00logcfu/mL until the end of the storage period. Moreover, comparing the microbial loads of samples containing both species and those containing S. thermophilus alone (C5), we highlighted the ability of L. plantarum to stimulate S. thermophilus replication. This boosted replication of S. thermophilus allowed to reach an appropriate pH in a time frame fitting the production schedule. This was not observed for samples containing a single species (C5-C9). Thus, L. plantarum strains seem to be good candidates in the production of a novel type of fermented milk, not only for their probiotic potential, but also for the enhancing effect on S. thermophilus growth.


Asunto(s)
Productos Lácteos Cultivados/microbiología , Lactobacillus plantarum/metabolismo , Leche/metabolismo , Muramidasa/metabolismo , Streptococcus thermophilus/metabolismo , Animales , Bebidas/microbiología , Reactores Biológicos , Equidae , Fermentación , Lactobacillus plantarum/aislamiento & purificación , Leche/química , Probióticos/metabolismo , Streptococcus thermophilus/aislamiento & purificación
19.
Vet Ital ; 53(1): 29-37, 2017 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-28365923

RESUMEN

In this study, the prevalence of Campylobacter spp. in poultry fresh meat and ready­to­cook products was evaluated. Seventy­three samples were collected at retail level from supermarkets and discount stores, obtaining 61.6% positivity. Of 133 Campylobacter isolates, 86 strains (Campylobacter coli, 58.1% and Campylobacter jejuni, 41.9%) were selected for characterisation on the basis of their SmaI and kpnI pulsed field gel­electrophoresis (PFGE) profiles, to exclude clonal replicates. Campylobacters resulted highly resistant to tetracycline, ciprofloxacin, and nalidixic acid (79.1%, 72.1% and 65.1%, respectively); 50% of C. coli and 13.9% of C. jejuni were resistant to ciprofloxacin and erythromycin, the most important antimicrobials for human campylobacteriosis therapy. Five C. coli were resistant to 5/7 of the tested antimicrobials. HS4c was the prevailing C. jejuni serotype group (22.3%), whereas 8 other serotypes were identified in low percentages. SmaI and kpnI profiles showed a wide variability. The survey showed a high Campylobacter contamination of poultry meat and poultry products at retail level in Tuscany, Italy. A wide strains' heterogeneity and a remarkable level of strains' antimicrobial resistance have been reported, confirming the need for an improvement of specific preventive measures along the production chain.


Asunto(s)
Campylobacter/aislamiento & purificación , Contaminación de Alimentos/análisis , Carne/microbiología , Productos Avícolas/microbiología , Animales , Antibacterianos/farmacología , Campylobacter/clasificación , Campylobacter/genética , Comercio , Farmacorresistencia Bacteriana , Variación Genética , Humanos , Italia , Pruebas de Sensibilidad Microbiana , Aves de Corral/microbiología , Prevalencia
20.
Meat Sci ; 129: 161-168, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28314171

RESUMEN

Pork burgers were evaluated for physical-chemical characteristics, fatty acids profile, lipid oxidation, antioxidant capacity, microbiological growth and sensory evaluation during storage time of seven days at 4°C as function of three formulations as only meat (control, B) and meat added with ginger powder at the percentage of 1 and 2% (BG1 and BG2). BG1 and BG2 were less redness than control ones with incremented yellow hue. These modifications in color parameters did not modify sensory characteristics of burgers. PUFA were incremented (both PUFAω3 and PUFAω6) by the addition of ginger. Furthermore, BG1 and BG2 burgers showed to be less sensitive to lipid oxidation and to possess an increase in antioxidant capacity. Microbial growth evaluation of total aerobic count and Pseudomonas spp. showed that ginger powder delayed in time the bacterial contamination. Results highlighted that the presence of ginger led to an enhanced shelf life and health characteristics of burgers (increasing peroxidisability, ratio hypocholesterolemic/hypercholesterolemic and ratio ω3/ω6; reducing atherogenicity and thrombogenicity).


Asunto(s)
Productos de la Carne/análisis , Carne Roja/análisis , /química , Animales , Antioxidantes/análisis , Bacterias Aerobias/aislamiento & purificación , Recuento de Colonia Microbiana , Color , Ácidos Grasos/análisis , Microbiología de Alimentos , Almacenamiento de Alimentos , Peroxidación de Lípido , Productos de la Carne/microbiología , Polvos , Pseudomonas/aislamiento & purificación , Carne Roja/microbiología , Sus scrofa
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