Alberto Vergara - Academia.edu (original) (raw)

Papers by Alberto Vergara

Foods

The antibiotic resistance phenomenon horizontally involves numerous bacteria cultured from fresh ... more The antibiotic resistance phenomenon horizontally involves numerous bacteria cultured from fresh or processed seafood matrix microbiomes. In this study, the identified bacteria from food-producing processes and industrial environments were screened for phenotypic and genotypic resistance determinants. A total of 684 bacterial strains [537 from processed codfish (Gadus morhua and Gadus macrocephalus) products as salted and seasoned and soaked and 147 from environmental samples] were isolated. Antibiotic susceptibility tests showed resistance against tetracycline, oxacillin, and clindamycin in the Staphylococcus genus (both from food and environmental samples) and against beta-lactams (cefotaxime, carbapenems, etc.) and nitrofurans (nitrofurantoin) from E. coli and Salmonella enterica serovar. Enteritidis isolates. One-thousand and ten genetic determinants—tetracycline tetC (25.17%), tetK (21.06%), tetL (11.70%), clindamycin ermC (17.23%), ermB (7.60%), linezolid cfr (8.22%), optrA (3...

Foods

An efficient microbiological decontamination protocol is required to guarantee safe food products... more An efficient microbiological decontamination protocol is required to guarantee safe food products for the final consumer to avoid foodborne illnesses. Ultrasound and non-thermal technology combinations represent innovative methods adopted by the food industry for food preservation and safety. Ultrasound power is commonly used with a frequency between 20 and 100 kHz to obtain an “exploit cavitation effect”. Microbial inactivation via ultrasound derives from cell wall damage, the oxidation of intracellular amino acids and DNA changing material. As an inactivation method, it is evaluated alone and combined with other non-thermal technologies. The evidence shows that ultrasound is an important green technology that has a good decontamination effect and can improve the shelf-life of products. This review aims to describe the applicability of ultrasound in the food industry focusing on microbiological decontamination, reducing bacterial alterations caused by food spoilage strains and rela...

Animals

Antimicrobial resistance (AMR) is a global health concern that has been linked to humans, animals... more Antimicrobial resistance (AMR) is a global health concern that has been linked to humans, animals, and the environment. The One Health approach highlights the connection between humans, animals, and the environment and suggests that a multidisciplinary approached be used in studies investigating AMR. The present study was carried out to identify and characterize the antimicrobial resistance profiles of bacteria isolated from wildlife and livestock feces as well as from surface water samples in Maiella National Park, Italy. Ecological and georeferenced data were used to select two sampling locations, one where wildlife was caught within livestock grazing areas (sympatric group) and one where wildlife was caught outside of livestock grazing areas (non-sympatric group). Ninety-nine bacterial isolates from 132 feces samples and seven isolates from five water samples were collected between October and December 2019. The specimens were examined for species identification, antibiotic susce...

aivi.it

GENOTYPIC CHARACTERIZATION OF LISTERIA MONOCYTOGENES ISOLATED FROM FOODS AND FOOD ENVIRONMENTS. C... more GENOTYPIC CHARACTERIZATION OF LISTERIA MONOCYTOGENES ISOLATED FROM FOODS AND FOOD ENVIRONMENTS. Conter M., Di Ciccio P. 1 , Zanardi E., D'Orio V. 1 , Ghidini S., Vergara A. 1 , Ianieri A. Dipartimento ...

Frontiers in Microbiology, 2022

Antimicrobial resistance (AMR) is a global concern, and new approaches are needed to circumvent a... more Antimicrobial resistance (AMR) is a global concern, and new approaches are needed to circumvent animal and food-borne resistant pathogens. Among the new strategies, the combination of antibiotics with natural compounds such as essential oils (EOs) could be an alternative to challenge bacterial resistance. The present study evaluates the phenotypic and genotypic antibiotic resistance of 36 Salmonella enterica (16 S. Typhimurium, 3 monophasic variant S. Typhimurium, 8 S. Enteritidis, 6 S. Rissen, 1 S. Typhi, and 2 S. Derby) strains, isolated from the swine production chain. The isolates displayed phenotypic resistance to gentamicin, amikacin, tobramycin, and tetracycline, while the resistance genes most commonly detected were parC, catA, nfsB, nfsA, blaTEM, tetA, and tetB. Then 31/36 Salmonella isolates were chosen to evaluate resistance to tetracycline and Thymus vulgaris, Eugenia caryophyllata, and Corydothymus capitatus EOs by determining minimum inhibitory concentrations (MICs). F...

Italian Journal of Food Safety

The intradiaphragmatic localization of an abscess is rarely described in humans and in other anim... more The intradiaphragmatic localization of an abscess is rarely described in humans and in other animal domestic and wild species, and can be caused by penetrative traumas (i.e., firearm injuries). Here we describe two intradiaphragmatic abscesses in a hunted adult male wild boar (Sus scrofa) pluck, associated with adhesion phenomena with the contiguous anatomical structures (pleural, phrenic, and glissonian serosas) and observed during the post mortem inspection, in accordance with the Reg. EU 627/2019. One of these lesions also presented a phreno-abdominal fistula. We found in cytopathological evaluation of the neoformations’ content the presence of spheroidal bacterial soma, characterized by linearly concatenated “Streptococcus-like” aggregation pattern. Furthermore, microbiological assays revealed a polymicrobial pattern characterized by the presence of telluric microorganisms, some of which have a marked pyogenic action (Streptococcus suis type I, Sphingomonas paucimobilis, Carnoba...

Italian Journal of Food Science, 2014

Italian Journal of Food Safety

Hepatitis E virus (HEV) is a zoonotic pathogen, responsible for numerous cases of infection in hu... more Hepatitis E virus (HEV) is a zoonotic pathogen, responsible for numerous cases of infection in humans. Transmission occurs through the orofecal route, and ingestion of contaminated foods represents an important risk factor for final consumer’s health. Wild animal species, in particular wild boar (Sus scrofa), are the main virus reservoirs; liver is the target organ, from which, through the hematic diffusion, HEV reaches different tissues and organs, as muscular one. The hygienic-sanitary critical issues connected with game meat food chain in general, and particularly wild boar, with special regards to any geographical area where this animal species can be directly in contact with humans, domestic ones (i.e., domestic pig), and other wild reservoirs (i.e., wild ruminants), finds favorable environmental conditions, have induced us to conduce the present scientific investigation. During the hunting season 2019/2020, a total of 156 wild boar livers were collected from provided plucks at...

Antibiotics

The aim of this study was to evaluate the resistance patterns against selected critically and hig... more The aim of this study was to evaluate the resistance patterns against selected critically and highly important antibiotics (quinupristin/dalfopristin, vancomycin, and linezolid) in 48 Enterococcus isolates obtained from wild (red deer and Apennine chamois) and domestic (cattle, sheep, and goats) ruminants living with varying degrees of sympatry in the protected area of Maiella National Park (central Italy). According to CLSI breakpoints, 9 out of 48 isolates (18.8%) showed resistance to at least one antibiotic. One Apennine chamois isolate was resistant to all tested antibiotics. The PCR screening of related resistance genes highlighted the occurrence of msrC or cfrD in seven Enterococcus resistant isolates. In addition, msrC and vanC genes were amplified in susceptible isolates. Specific sequences of virulence genes (gelE, ace, efa, asa1, and esp) related to pathogenic enterococci in humans were amplified in 21/48 isolates (43.75%), belonging mostly to wild animals (15/21; 71.42%)....

Industrie Alimentari, 2008

The social, economical, technological and production aspects in traditional workshops processing ... more The social, economical, technological and production aspects in traditional workshops processing "Porchetta Abruzzese" were evaluated. A significant number of them (16) were tested for: the application of Good Manufacturing Practices, the level of training of the personnel and the hygienic and sanitary conditions of the working environment (after cleaning and sanitization) and of the operators (before starting work). The results showed that 75% of the workshops were family run businesses, with an annual production of less than 200 porchetta. According to the data obtained from the questionnaires, all the workshops tested were consistent to the GMP rules. The microbiological data, however, showed non adequate hygienic conditions regarding both the working environments and the operators in 11 workshops. Pathogen microrganisms such as S. aureus and L. monocytogenes were only found occasionally. In conclusion, the need to instil a "hygenic knowledge", in the operator...

Frontiers in Microbiology, 2021

Graphical Listeria monocytogenes activates the two-component system LisRK under stress, and becom... more Graphical Listeria monocytogenes activates the two-component system LisRK under stress, and becomes more adhesive and highly tolerant to ampicillin.

Foodborne Pathogens and Disease, 2017

Toxoplasmosis is a foodborne zoonosis transmitted by Toxoplasma gondii, a cosmopolitan protozoan ... more Toxoplasmosis is a foodborne zoonosis transmitted by Toxoplasma gondii, a cosmopolitan protozoan that infects humans through exposure to different parasite stages, in particular by ingestion of tissue cysts or tachyzoites contained in meat, primary offal (viscera), and meat-derived products or ingestion of environmental sporulated oocysts in contaminated food or water. The pig is an important species for infection: raw or undercooked pork consumption not subject to treatment able to inactivate the parasite represents a risk to consumers' health. Broadening knowledge of transmission ways and prevalence concerning this important pathogen in swine, together with a thorough acquaintance with hazard management are key elements to avoid T. gondii spreading within the swine production chain. This review aims to illustrate why toxoplasmosis should be regarded as a veterinary public health issue through a careful description of the parasite, routes of infection, and inactivation treatments, highlighting the main prevention lines from pig breeding to pork consumption.

Journal of Food Protection, 2017

To evaluate the occurrence of Toxoplasma gondii and to genetically characterize its isolates in c... more To evaluate the occurrence of Toxoplasma gondii and to genetically characterize its isolates in carcasses of industrial fattening pigs, blood, diaphragm, and heart samples were collected from 375 carcasses of pigs slaughtered to be processed for Parma ham production. Pigs had been bred on approved farms (n = 75) located in the so-called Food Valley in Italy. Sera were examined for immunoglobulin G antibodies to T. gondii by modified agglutination test (MAT). Both heart and diaphragm samples from seropositive carcasses were processed for the presence of T. gondii DNA (B1 locus) by real-time PCR and high resolution melting (HRM) assay. Anti-Toxoplasma antibodies were detected in 2.1% of pig carcasses, with titers from 1:10 to 1:320. T. gondii DNA was detected in all (eight) seropositive carcasses and in 11 (5 heart and 6 diaphragm samples) of 16 samples; that is, it was detected in heart tissue in two subjects, in diaphragm tissue in three subjects, and in both muscle tissues in three...

Journal of biological regulators and homeostatic agents

There is increasing concern about the impact on public health of methicillin-resistant Staphyloco... more There is increasing concern about the impact on public health of methicillin-resistant Staphylococcus aureus (MRSA) associated with animal food products. MRSA remains a serious problem because of the high incidence and multidrug resistance of the strains, even for strains isolated from foods, food environments and food handlers. The objectives of this study are: (i) to evaluate the susceptibility of S. aureus strains isolated from food, food handlers and food-processing environments to 14 antibiotics currently used in veterinary and human therapy; (ii) to assess the presence of the mecA gene. A total of 1007 samples were collected from food, food handlers, and environments and were analyzed for the presence of S. aureus. S. aureus was present in 165 of the 1007 samples. A total of 157 isolates were methicillin-susceptible S. aureus (MSSA) and 8 isolates were MRSA. In particular, out of 8 MRSA strains detected, 4 strains harboured the mecA gene. All MRSA strains were resistant to at ...

Foods

The antibiotic resistance phenomenon horizontally involves numerous bacteria cultured from fresh ... more The antibiotic resistance phenomenon horizontally involves numerous bacteria cultured from fresh or processed seafood matrix microbiomes. In this study, the identified bacteria from food-producing processes and industrial environments were screened for phenotypic and genotypic resistance determinants. A total of 684 bacterial strains [537 from processed codfish (Gadus morhua and Gadus macrocephalus) products as salted and seasoned and soaked and 147 from environmental samples] were isolated. Antibiotic susceptibility tests showed resistance against tetracycline, oxacillin, and clindamycin in the Staphylococcus genus (both from food and environmental samples) and against beta-lactams (cefotaxime, carbapenems, etc.) and nitrofurans (nitrofurantoin) from E. coli and Salmonella enterica serovar. Enteritidis isolates. One-thousand and ten genetic determinants—tetracycline tetC (25.17%), tetK (21.06%), tetL (11.70%), clindamycin ermC (17.23%), ermB (7.60%), linezolid cfr (8.22%), optrA (3...

Foods

An efficient microbiological decontamination protocol is required to guarantee safe food products... more An efficient microbiological decontamination protocol is required to guarantee safe food products for the final consumer to avoid foodborne illnesses. Ultrasound and non-thermal technology combinations represent innovative methods adopted by the food industry for food preservation and safety. Ultrasound power is commonly used with a frequency between 20 and 100 kHz to obtain an “exploit cavitation effect”. Microbial inactivation via ultrasound derives from cell wall damage, the oxidation of intracellular amino acids and DNA changing material. As an inactivation method, it is evaluated alone and combined with other non-thermal technologies. The evidence shows that ultrasound is an important green technology that has a good decontamination effect and can improve the shelf-life of products. This review aims to describe the applicability of ultrasound in the food industry focusing on microbiological decontamination, reducing bacterial alterations caused by food spoilage strains and rela...

Animals

Antimicrobial resistance (AMR) is a global health concern that has been linked to humans, animals... more Antimicrobial resistance (AMR) is a global health concern that has been linked to humans, animals, and the environment. The One Health approach highlights the connection between humans, animals, and the environment and suggests that a multidisciplinary approached be used in studies investigating AMR. The present study was carried out to identify and characterize the antimicrobial resistance profiles of bacteria isolated from wildlife and livestock feces as well as from surface water samples in Maiella National Park, Italy. Ecological and georeferenced data were used to select two sampling locations, one where wildlife was caught within livestock grazing areas (sympatric group) and one where wildlife was caught outside of livestock grazing areas (non-sympatric group). Ninety-nine bacterial isolates from 132 feces samples and seven isolates from five water samples were collected between October and December 2019. The specimens were examined for species identification, antibiotic susce...

aivi.it

GENOTYPIC CHARACTERIZATION OF LISTERIA MONOCYTOGENES ISOLATED FROM FOODS AND FOOD ENVIRONMENTS. C... more GENOTYPIC CHARACTERIZATION OF LISTERIA MONOCYTOGENES ISOLATED FROM FOODS AND FOOD ENVIRONMENTS. Conter M., Di Ciccio P. 1 , Zanardi E., D'Orio V. 1 , Ghidini S., Vergara A. 1 , Ianieri A. Dipartimento ...

Frontiers in Microbiology, 2022

Antimicrobial resistance (AMR) is a global concern, and new approaches are needed to circumvent a... more Antimicrobial resistance (AMR) is a global concern, and new approaches are needed to circumvent animal and food-borne resistant pathogens. Among the new strategies, the combination of antibiotics with natural compounds such as essential oils (EOs) could be an alternative to challenge bacterial resistance. The present study evaluates the phenotypic and genotypic antibiotic resistance of 36 Salmonella enterica (16 S. Typhimurium, 3 monophasic variant S. Typhimurium, 8 S. Enteritidis, 6 S. Rissen, 1 S. Typhi, and 2 S. Derby) strains, isolated from the swine production chain. The isolates displayed phenotypic resistance to gentamicin, amikacin, tobramycin, and tetracycline, while the resistance genes most commonly detected were parC, catA, nfsB, nfsA, blaTEM, tetA, and tetB. Then 31/36 Salmonella isolates were chosen to evaluate resistance to tetracycline and Thymus vulgaris, Eugenia caryophyllata, and Corydothymus capitatus EOs by determining minimum inhibitory concentrations (MICs). F...

Italian Journal of Food Safety

The intradiaphragmatic localization of an abscess is rarely described in humans and in other anim... more The intradiaphragmatic localization of an abscess is rarely described in humans and in other animal domestic and wild species, and can be caused by penetrative traumas (i.e., firearm injuries). Here we describe two intradiaphragmatic abscesses in a hunted adult male wild boar (Sus scrofa) pluck, associated with adhesion phenomena with the contiguous anatomical structures (pleural, phrenic, and glissonian serosas) and observed during the post mortem inspection, in accordance with the Reg. EU 627/2019. One of these lesions also presented a phreno-abdominal fistula. We found in cytopathological evaluation of the neoformations’ content the presence of spheroidal bacterial soma, characterized by linearly concatenated “Streptococcus-like” aggregation pattern. Furthermore, microbiological assays revealed a polymicrobial pattern characterized by the presence of telluric microorganisms, some of which have a marked pyogenic action (Streptococcus suis type I, Sphingomonas paucimobilis, Carnoba...

Italian Journal of Food Science, 2014

Italian Journal of Food Safety

Hepatitis E virus (HEV) is a zoonotic pathogen, responsible for numerous cases of infection in hu... more Hepatitis E virus (HEV) is a zoonotic pathogen, responsible for numerous cases of infection in humans. Transmission occurs through the orofecal route, and ingestion of contaminated foods represents an important risk factor for final consumer’s health. Wild animal species, in particular wild boar (Sus scrofa), are the main virus reservoirs; liver is the target organ, from which, through the hematic diffusion, HEV reaches different tissues and organs, as muscular one. The hygienic-sanitary critical issues connected with game meat food chain in general, and particularly wild boar, with special regards to any geographical area where this animal species can be directly in contact with humans, domestic ones (i.e., domestic pig), and other wild reservoirs (i.e., wild ruminants), finds favorable environmental conditions, have induced us to conduce the present scientific investigation. During the hunting season 2019/2020, a total of 156 wild boar livers were collected from provided plucks at...

Antibiotics

The aim of this study was to evaluate the resistance patterns against selected critically and hig... more The aim of this study was to evaluate the resistance patterns against selected critically and highly important antibiotics (quinupristin/dalfopristin, vancomycin, and linezolid) in 48 Enterococcus isolates obtained from wild (red deer and Apennine chamois) and domestic (cattle, sheep, and goats) ruminants living with varying degrees of sympatry in the protected area of Maiella National Park (central Italy). According to CLSI breakpoints, 9 out of 48 isolates (18.8%) showed resistance to at least one antibiotic. One Apennine chamois isolate was resistant to all tested antibiotics. The PCR screening of related resistance genes highlighted the occurrence of msrC or cfrD in seven Enterococcus resistant isolates. In addition, msrC and vanC genes were amplified in susceptible isolates. Specific sequences of virulence genes (gelE, ace, efa, asa1, and esp) related to pathogenic enterococci in humans were amplified in 21/48 isolates (43.75%), belonging mostly to wild animals (15/21; 71.42%)....

Industrie Alimentari, 2008

The social, economical, technological and production aspects in traditional workshops processing ... more The social, economical, technological and production aspects in traditional workshops processing "Porchetta Abruzzese" were evaluated. A significant number of them (16) were tested for: the application of Good Manufacturing Practices, the level of training of the personnel and the hygienic and sanitary conditions of the working environment (after cleaning and sanitization) and of the operators (before starting work). The results showed that 75% of the workshops were family run businesses, with an annual production of less than 200 porchetta. According to the data obtained from the questionnaires, all the workshops tested were consistent to the GMP rules. The microbiological data, however, showed non adequate hygienic conditions regarding both the working environments and the operators in 11 workshops. Pathogen microrganisms such as S. aureus and L. monocytogenes were only found occasionally. In conclusion, the need to instil a "hygenic knowledge", in the operator...

Frontiers in Microbiology, 2021

Graphical Listeria monocytogenes activates the two-component system LisRK under stress, and becom... more Graphical Listeria monocytogenes activates the two-component system LisRK under stress, and becomes more adhesive and highly tolerant to ampicillin.

Foodborne Pathogens and Disease, 2017

Toxoplasmosis is a foodborne zoonosis transmitted by Toxoplasma gondii, a cosmopolitan protozoan ... more Toxoplasmosis is a foodborne zoonosis transmitted by Toxoplasma gondii, a cosmopolitan protozoan that infects humans through exposure to different parasite stages, in particular by ingestion of tissue cysts or tachyzoites contained in meat, primary offal (viscera), and meat-derived products or ingestion of environmental sporulated oocysts in contaminated food or water. The pig is an important species for infection: raw or undercooked pork consumption not subject to treatment able to inactivate the parasite represents a risk to consumers' health. Broadening knowledge of transmission ways and prevalence concerning this important pathogen in swine, together with a thorough acquaintance with hazard management are key elements to avoid T. gondii spreading within the swine production chain. This review aims to illustrate why toxoplasmosis should be regarded as a veterinary public health issue through a careful description of the parasite, routes of infection, and inactivation treatments, highlighting the main prevention lines from pig breeding to pork consumption.

Journal of Food Protection, 2017

To evaluate the occurrence of Toxoplasma gondii and to genetically characterize its isolates in c... more To evaluate the occurrence of Toxoplasma gondii and to genetically characterize its isolates in carcasses of industrial fattening pigs, blood, diaphragm, and heart samples were collected from 375 carcasses of pigs slaughtered to be processed for Parma ham production. Pigs had been bred on approved farms (n = 75) located in the so-called Food Valley in Italy. Sera were examined for immunoglobulin G antibodies to T. gondii by modified agglutination test (MAT). Both heart and diaphragm samples from seropositive carcasses were processed for the presence of T. gondii DNA (B1 locus) by real-time PCR and high resolution melting (HRM) assay. Anti-Toxoplasma antibodies were detected in 2.1% of pig carcasses, with titers from 1:10 to 1:320. T. gondii DNA was detected in all (eight) seropositive carcasses and in 11 (5 heart and 6 diaphragm samples) of 16 samples; that is, it was detected in heart tissue in two subjects, in diaphragm tissue in three subjects, and in both muscle tissues in three...

Journal of biological regulators and homeostatic agents

There is increasing concern about the impact on public health of methicillin-resistant Staphyloco... more There is increasing concern about the impact on public health of methicillin-resistant Staphylococcus aureus (MRSA) associated with animal food products. MRSA remains a serious problem because of the high incidence and multidrug resistance of the strains, even for strains isolated from foods, food environments and food handlers. The objectives of this study are: (i) to evaluate the susceptibility of S. aureus strains isolated from food, food handlers and food-processing environments to 14 antibiotics currently used in veterinary and human therapy; (ii) to assess the presence of the mecA gene. A total of 1007 samples were collected from food, food handlers, and environments and were analyzed for the presence of S. aureus. S. aureus was present in 165 of the 1007 samples. A total of 157 isolates were methicillin-susceptible S. aureus (MSSA) and 8 isolates were MRSA. In particular, out of 8 MRSA strains detected, 4 strains harboured the mecA gene. All MRSA strains were resistant to at ...