RESUMO

Induction of resistance in common bean (Phaseolus vulgaris) has been considered a promising alternative to control anthracnose. Among the changes generated in the induction of resistance, structural changes have been reported by several authors as an efficient form of resistance to the stress plants undergo. Histochemical analysis techniques have been used to investigate tissue changes triggered by induction of resistance. Thus, this study aims to investigate certain histochemical changes suffered by common bean plants induced with potassium phosphite and Trichoderma spp. in response to the attack by Colletotrichum lindemuthianum, aiming to determine the host response pattern in terms of structural changes, associating it to possible disease control. Treatments consisted of isolates T. harzianum (isolate TOD1) and T. virens (isolate TM4), leaf fertilizer potassium phosphite Fertilis®, and distilled water (control). Inducers were applied to common bean alone or associated, consisting of five treatments plus the control treatment. The six treatments were evaluated for the absence and presence of C. lindemuthianum in a factorial scheme (6×2). Treatments allowed evaluating the severity of anthracnose in common bean, location of H2O2, lignin deposition, and hypersensitivity response in common bean hypocotyl by histochemical staining. Potassium phosphite and combinations of T. virens and T. harzianum with potassium phosphite efficiently reduced disease severity under greenhouse conditions, reaching 68, 84, and 71%, respectively. Studies with hypocotyl showed that T. harzianum + potassium phosphite and T. virens + potassium phosphite accelerated the H2O2 accumulation process and lignin deposition at the pathogen penetration site, in addition to the hypersensitivity reaction through the resistance-inducing activity, contributing to the protection of common bean against anthracnose caused by C. lindemuthianum.(AU)

No cultivo do feijoeiro (Phaseolus vulgaris) a indução de resistência tem sido considerada uma alternativa promissora para o controle da antracnose. Dentre as alterações geradas na indução de resistência, as mudanças estruturais têm sido relatadas por diversos autores como uma forma eficiente de resistência ao estresse sofrido pela planta. Técnicas de análises histoquímicas têm sido utilizadas com o objetivo de investigar as alterações teciduais desencadeadas pela indução de resistência. Dessa forma, o presente trabalho tem por objetivo investigar determinadas alterações histoquímicas sofridas pelas plantas de feijoeiro induzidas com fosfito de potássio e Trichoderma spp. frente ao ataque de Colletotrichum lindemuthianum, visando determinar o padrão de resposta do hospedeiro em termos de modificações estruturais, associando esse padrão de resposta ao possível controle da doença. Os tratamentos consistiram de dois isolados: T. harzianum (isolado TOD1) e T. virens (isolado TM4), do fertilizante foliar Fosfito de Potássio Fertilis® e do tratamento com água destilada (controle). Os indutores foram aplicados no feijoeiro isoladamente ou combinados, constituindo cinco tratamentos mais o tratamento controle. Os seis tratamentos foram avaliados na ausência e presença de C. lindemuthianum em esquema fatorial (6x2). Mediante os tratamentos realizados, avaliou-se a severidade da antracnose no feijoeiro; localização de H2O2; deposição de lignina e resposta de hipersensibilidade em hipocótilo de feijoeiro por colorações histoquímicas. Em condições de casa de vegetação verificou-se que o fosfito de potássio e as combinações de Trichoderma virens e Trichoderma harzianum com fosfito de potássio reduziram de forma eficiente a severidade da doença, alcançando 68%, 84% e 71% respectivamente. Nos estudos com o hipocótilo, verificou-se que Trichoderma harzianum + fosfito de potássio...(AU)

Assuntos

RESUMO

Induction of resistance in common bean (Phaseolus vulgaris) has been considered a promising alternative to control anthracnose. Among the changes generated in the induction of resistance, structural changes have been reported by several authors as an efficient form of resistance to the stress plants undergo. Histochemical analysis techniques have been used to investigate tissue changes triggered by induction of resistance. Thus, this study aims to investigate certain histochemical changes suffered by common bean plants induced with potassium phosphite and Trichoderma spp. in response to the attack by Colletotrichum lindemuthianum, aiming to determine the host response pattern in terms of structural changes, associating it to possible disease control. Treatments consisted of isolates T. harzianum (isolate TOD1) and T. virens (isolate TM4), leaf fertilizer potassium phosphite Fertilis®, and distilled water (control). Inducers were applied to common bean alone or associated, consisting of five treatments plus the control treatment. The six treatments were evaluated for the absence and presence of C. lindemuthianum in a factorial scheme (6×2). Treatments allowed evaluating the severity of anthracnose in common bean, location of H2O2, lignin deposition, and hypersensitivity response in common bean hypocotyl by histochemical staining. Potassium phosphite and combinations of T. virens and T. harzianum with potassium phosphite efficiently reduced disease severity under greenhouse conditions, reaching 68, 84, and 71%, respectively. Studies with hypocotyl showed that T. harzianum + potassium phosphite and T. virens + potassium phosphite accelerated the H2O2 accumulation process and lignin deposition at the pathogen penetration site, in addition to the hypersensitivity reaction through the resistance-inducing activity, contributing to the protection of common bean against anthracnose caused by C. lindemuthianum.

No cultivo do feijoeiro (Phaseolus vulgaris) a indução de resistência tem sido considerada uma alternativa promissora para o controle da antracnose. Dentre as alterações geradas na indução de resistência, as mudanças estruturais têm sido relatadas por diversos autores como uma forma eficiente de resistência ao estresse sofrido pela planta. Técnicas de análises histoquímicas têm sido utilizadas com o objetivo de investigar as alterações teciduais desencadeadas pela indução de resistência. Dessa forma, o presente trabalho tem por objetivo investigar determinadas alterações histoquímicas sofridas pelas plantas de feijoeiro induzidas com fosfito de potássio e Trichoderma spp. frente ao ataque de Colletotrichum lindemuthianum, visando determinar o padrão de resposta do hospedeiro em termos de modificações estruturais, associando esse padrão de resposta ao possível controle da doença. Os tratamentos consistiram de dois isolados: T. harzianum (isolado TOD1) e T. virens (isolado TM4), do fertilizante foliar Fosfito de Potássio Fertilis® e do tratamento com água destilada (controle). Os indutores foram aplicados no feijoeiro isoladamente ou combinados, constituindo cinco tratamentos mais o tratamento controle. Os seis tratamentos foram avaliados na ausência e presença de C. lindemuthianum em esquema fatorial (6x2). Mediante os tratamentos realizados, avaliou-se a severidade da antracnose no feijoeiro; localização de H2O2; deposição de lignina e resposta de hipersensibilidade em hipocótilo de feijoeiro por colorações histoquímicas. Em condições de casa de vegetação verificou-se que o fosfito de potássio e as combinações de Trichoderma virens e Trichoderma harzianum com fosfito de potássio reduziram de forma eficiente a severidade da doença, alcançando 68%, 84% e 71% respectivamente. Nos estudos com o hipocótilo, verificou-se que Trichoderma harzianum + fosfito de potássio...

Assuntos

RESUMO

In this study, we investigated the contamination of refrigerated raw milk produced in the western region of Paraná, southern Brazil, with psychrotrophic microorganisms, aiming to assay the proteolytic activity of the isolates and to identify Pseudomonas fluorescens, the main proteolytic species associated with the spoilage of milk products. Raw milk samples from 50 dairy farms were submitted to the counting of psychrotrophic microorganisms, being the microbiota characterized by its mesophilic behavior and proteolytic capacity, besides molecular identification of P. fluorescens. Of the samples evaluated, 94% had psychrotrophic counts ranging from 3 to 7.1 log CFU mL-1, and 48.5% of these showed mesophilic behavior. Of the isolates, 48.0% had proteolytic activity in at least one evaluated temperature (21 and 30°C), and 39.3% had proteolytic activity in both temperatures. Among the 61 isolates submitted to molecular identification by polymerase chain reaction (PCR), 86.8% contained the expression of the 16S gene characteristic for P. fluorescens. In this study, we demonstrated that P. fluorescens is the most prevalent psychrotrophic bacteria species in raw refrigerated milk and their proteolytic ability poses high risks to the dairy industry.(AU)

No presente estudo, investigamos a contaminação do leite cru refrigerado produzido na região oeste do Paraná, sul do Brasil, com micro-organismos psicrotróficos, visando testar a atividade proteolítica dos isolados e identificar Pseudomonas fluorescens, a principal espécie proteolítica associada à deterioração de produtos lácteos. Amostras de leite cru de 50 fazendas leiteiras foram submetidas à contagem de micro-organismos psicrotróficos, caracterizando-se a microbiota por seu comportamento mesofílico e sua capacidade proteolítica, além de identificação molecular de P. fluorescens. Entre as amostras avaliadas, 94% apresentaram contagem psicrotrófica variando de 3 a 7,1 log UFC mL-1 e 48,5% destas apresentaram comportamento mesofílico. Entre os isolados, 48,0% apresentaram atividade proteolítica em pelo menos uma das temperaturas testadas (21 e 30°C) e 39,3% apresentaram atividade proteolítica em ambas as temperaturas. Entre os 61 isolados sub-metidos à identificação molecular por reação em cadeia da polimerase (PCR), 86,8% continham expressão do gene 16S característico de P. fluorescens. Neste estudo, demonstramos que P. fluorescens é a espécie de bactérias psicrotróficas mais prevalente em leite refrigerado cru e sua capacidade proteolítica promove elevados riscos de deterioração para a indústria de laticínios.(AU)

Assuntos

RESUMO

In this study, we investigated the contamination of refrigerated raw milk produced in the western region of Paraná, southern Brazil, with psychrotrophic microorganisms, aiming to assay the proteolytic activity of the isolates and to identify Pseudomonas fluorescens, the main proteolytic species associated with the spoilage of milk products. Raw milk samples from 50 dairy farms were submitted to the counting of psychrotrophic microorganisms, being the microbiota characterized by its mesophilic behavior and proteolytic capacity, besides molecular identification of P. fluorescens. Of the samples evaluated, 94% had psychrotrophic counts ranging from 3 to 7.1 log CFU mL-1, and 48.5% of these showed mesophilic behavior. Of the isolates, 48.0% had proteolytic activity in at least one evaluated temperature (21 and 30°C), and 39.3% had proteolytic activity in both temperatures. Among the 61 isolates submitted to molecular identification by polymerase chain reaction (PCR), 86.8% contained the expression of the 16S gene characteristic for P. fluorescens. In this study, we demonstrated that P. fluorescens is the most prevalent psychrotrophic bacteria species in raw refrigerated milk and their proteolytic ability poses high risks to the dairy industry.(AU)

No presente estudo, investigamos a contaminação do leite cru refrigerado produzido na região oeste do Paraná, sul do Brasil, com micro-organismos psicrotróficos, visando testar a atividade proteolítica dos isolados e identificar Pseudomonas fluorescens, a principal espécie proteolítica associada à deterioração de produtos lácteos. Amostras de leite cru de 50 fazendas leiteiras foram submetidas à contagem de micro-organismos psicrotróficos, caracterizando-se a microbiota por seu comportamento mesofílico e sua capacidade proteolítica, além de identificação molecular de P. fluorescens. Entre as amostras avaliadas, 94% apresentaram contagem psicrotrófica variando de 3 a 7,1 log UFC mL-1 e 48,5% destas apresentaram comportamento mesofílico. Entre os isolados, 48,0% apresentaram atividade proteolítica em pelo menos uma das temperaturas testadas (21 e 30°C) e 39,3% apresentaram atividade proteolítica em ambas as temperaturas. Entre os 61 isolados sub-metidos à identificação molecular por reação em cadeia da polimerase (PCR), 86,8% continham expressão do gene 16S característico de P. fluorescens. Neste estudo, demonstramos que P. fluorescens é a espécie de bactérias psicrotróficas mais prevalente em leite refrigerado cru e sua capacidade proteolítica promove elevados riscos de deterioração para a indústria de laticínios.(AU)

Assuntos

RESUMO

Abstract The aim of this study was to investigate the occurrence of multidrug-resistant, extended spectrum beta-lactamase (ESBL) producing Salmonella spp. isolated from conveyor belts of broiler cutting rooms in Brazilian broiler processing plants. Ninety-eight strains of Salmonella spp. were analyzed. Multidrug resistance was determined by the disk diffusion test and the susceptibility of the isolated bacteria was evaluated against 18 antimicrobials from seven different classes. The double disk diffusion test was used to evaluate ESBL production. Of the 98 strains tested, 84 were multidrug resistant. The highest rates of resistance were against nalidixic acid (95%), tetracycline (91%), and the beta-lactams: ampicillin and cefachlor (45%), followed by streptomycin and gentamicin with 19% and 15% of strain resistance, respectively. By contrast, 97% of the strains were sensitive to chloramphenicol. 45% of the strains were positive for the presence of ESBL activity. In this study, high rates of multidrug resistance and ESBL production were observed in Salmonella spp.

Assuntos

RESUMO

The aim of this study was to investigate the occurrence of multidrug-resistant, extended spectrum beta-lactamase (ESBL) producing Salmonella spp. isolated from conveyor belts of broiler cutting rooms in Brazilian broiler processing plants. Ninety-eight strains of Salmonella spp. were analyzed. Multidrug resistance was determined by the disk diffusion test and the susceptibility of the isolated bacteria was evaluated against 18 antimicrobials from seven different classes. The double disk diffusion test was used to evaluate ESBL production. Of the 98 strains tested, 84 were multidrug resistant. The highest rates of resistance were against nalidixic acid (95%), tetracycline (91%), and the beta-lactams: ampicillin and cefachlor (45%), followed by streptomycin and gentamicin with 19% and 15% of strain resistance, respectively. By contrast, 97% of the strains were sensitive to chloramphenicol. 45% of the strains were positive for the presence of ESBL activity. In this study, high rates of multidrug resistance and ESBL production were observed in Salmonella spp.

Assuntos

RESUMO

The aim of this study was to investigate the occurrence of multidrug-resistant, extended spectrum beta-lactamase (ESBL) producing Salmonella spp. isolated from conveyor belts of broiler cutting rooms in Brazilian broiler processing plants. Ninety-eight strains of Salmonella spp. were analyzed. Multidrug resistance was determined by the disk diffusion test and the susceptibility of the isolated bacteria was evaluated against 18 antimicrobials from seven different classes. The double disk diffusion test was used to evaluate ESBL production. Of the 98 strains tested, 84 were multidrug resistant. The highest rates of resistance were against nalidixic acid (95%), tetracycline (91%), and the beta-lactams: ampicillin and cefachlor (45%), followed by streptomycin and gentamicin with 19% and 15% of strain resistance, respectively. By contrast, 97% of the strains were sensitive to chloramphenicol. 45% of the strains were positive for the presence of ESBL activity. In this study, high rates of multidrug resistance and ESBL production were observed in Salmonella spp. (AU)

Assuntos

RESUMO

O objetivo deste trabalho foi constatar a situação higienicossanitária de barracas de feiras livres localizadas em cinco municípios da região oeste do Paraná e a qualidade microbiológica e físico-química dos produtos nelas comercializados. Entre fevereiro e maio de 2013, foram realizadas avaliações, por meio do uso de checklist em 52 barracas onde foram adquiridas 71 amostras sendo estas submetidas à análise microbiológica e/ou físico-química. Foi constatado que em 47,9% das barracas o armazenamento dos alimentos era realizado de forma inadequada, que 86% dos produtos de origem animal estavam acondicionados em embalagens impróprias e que em 65% das mesmas, a condição higiênica dos manipuladores foi classificada como "Regular". Foram encontradas não conformidades em 36,6% das amostras submetidas às análises microbiológicas e/ou físico-químicas, sendo detectada a presença de Salmonella sp. em uma amostra de linguiça colonial. Sendo assim, é necessário que haja um controle sanitário na produção e comércio dos produtos nestas feiras por parte dos órgãos públicos responsáveis, garantindo assim, a segurança alimentar do consumidor.(AU)

The objective of this study was to determine the hygiene conditions of street market stands that sell products of animal origin in five cities in western Parana, Brazil, as well as the microbiological and physical-chemical quality of the products that are sold there. Between February and May, 2013, a total of 52 street market stands were analyzed based on a checklist. 71 samples were collected in these stands and submitted to microbiological and/or physical-chemical analyses. It was observed that in 47.9% of the stands, food products were inadequately stored; 86% of the products of animal origin were kept in improper containers; and in 65% of the stands, handler hygiene was classified as regular. 36.6% samples did not comply with microbiological and/or physical-chemical standards, with one sample of colonial sausage showing the presence of Salmonella sp. Therefore, public organisms control of hygiene in the production and commercialization of products in street markets is highly necessary to ensure food safety.(AU)

Assuntos

RESUMO

O objetivo deste trabalho foi constatar a situação higienicossanitária de barracas de feiras livres localizadas em cinco municípios da região oeste do Paraná e a qualidade microbiológica e físico-química dos produtos nelas comercializados. Entre fevereiro e maio de 2013, foram realizadas avaliações, por meio do uso de checklist em 52 barracas onde foram adquiridas 71 amostras sendo estas submetidas à análise microbiológica e/ou físico-química. Foi constatado que em 47,9% das barracas o armazenamento dos alimentos era realizado de forma inadequada, que 86% dos produtos de origem animal estavam acondicionados em embalagens impróprias e que em 65% das mesmas, a condição higiênica dos manipuladores foi classificada como "Regular". Foram encontradas não conformidades em 36,6% das amostras submetidas às análises microbiológicas e/ou físico-químicas, sendo detectada a presença de Salmonella sp. em uma amostra de linguiça colonial. Sendo assim, é necessário que haja um controle sanitário na produção e comércio dos produtos nestas feiras por parte dos órgãos públicos responsáveis, garantindo assim, a segurança alimentar do consumidor.

The objective of this study was to determine the hygiene conditions of street market stands that sell products of animal origin in five cities in western Parana, Brazil, as well as the microbiological and physical-chemical quality of the products that are sold there. Between February and May, 2013, a total of 52 street market stands were analyzed based on a checklist. 71 samples were collected in these stands and submitted to microbiological and/or physical-chemical analyses. It was observed that in 47.9% of the stands, food products were inadequately stored; 86% of the products of animal origin were kept in improper containers; and in 65% of the stands, handler hygiene was classified as regular. 36.6% samples did not comply with microbiological and/or physical-chemical standards, with one sample of colonial sausage showing the presence of Salmonella sp. Therefore, public organisms control of hygiene in the production and commercialization of products in street markets is highly necessary to ensure food safety.

Assuntos