Seletividade e produtividade de meios de cultura para isolamento de Campylobacter spp

A campilobacteriose é uma zoonose emergente de origem alimentar causada por bactérias do gênero Campylobacter. Vários fatores dificultam o isolamento deste patógeno em amostras naturalmente contaminadas, por isso devem ser utilizadas metodologias normalizadas bem como meios de cultura com desempenho adequado, prevenindo a ocorrência de resultados falso negativos. Assim, avaliou-se a performance de meios de cultura recomendados pelas ISO 10272-1 para detecção de Campylobacter spp. com testes de seletividade e produtividade em culturas puras e o desempenho destes meios em amostras de carne de frango artificialmente contaminadas. Cepas ATCC de C. coli e C. jejuni e dos interferentes S. aureus, E. coli e Proteus mirabilis foram inoculadas nos meios indicados pelas normas oficiais e posteriormente inoculados em amostras fortificadas. Os meios testados, tanto em culturas puras quanto em amostras fortificadas, tiveram desempenho satisfatório, mostrando boa seletividade e produtividade, permitindo que os laboratórios optem pela combinação de meios com melhor performance para isolamento e identificação de Campylobacter spp. em amostras naturalmente contaminadas.(AU)

Campylobacteriosis is an emerging foodborne zoonotic disease caused by bacteria of the genus Campylobacter. Several factors hinder the isolation of this pathogen in naturally contaminated samples; therefore, standardized methods as well as high performance culture media should be used to avoid false negative results. Thus, the present study assessed the performance of culture media recommended by ISO 10272- 1 for the detection of Campylobacter spp. using selectivity and productivity testing in pure cultures and the efficiency of these media in artificially contaminated, samples. ATCC strains of C. coli and C. jejuni and of the interfering organisms S. aureus, E. coli and Proteus mirabilis were inoculated into the media indicated by official standards and later inoculated into enriched samples. The media tested both in pure cultures and in enriched samples yielded satisfactory results, with good selectivity and productivity, there by allowing laboratories to combine high performance methods for the isolation and identification of Campylobacter spp. in naturally contaminated samples.(AU)

Seletividade e produtividade de meios de cultura para isolamento de Campylobacter spp / Selectivity and productivity of culture media for isolation of Campylobacter spp

[{"text": "A campilobacteriose é uma zoonose\r\nemergente de origem alimentar\r\ncausada por bactérias do gênero\r\nCampylobacter. Vários fatores dificultam\r\no isolamento deste patógeno\r\nem amostras naturalmente contaminadas,\r\npor isso devem ser utilizadas\r\nmetodologias normalizadas bem\r\ncomo meios de cultura com desempenho\r\nadequado, prevenindo a ocorrência\r\nde resultados falso negativos.\r\nAssim, avaliou-se a performance\r\nde meios de cultura recomendados\r\npelas ISO 10272-1 para detecção\r\nde Campylobacterspp. com testes\r\nde seletividade e produtividade em\r\nculturas puras e o desempenho destes\r\nmeios em amostras de carne de\r\nfrango artificialmente contaminadas.\r\nCepas ATCC de C. coli e C. jejuni e\r\ndos interferentes S. aureus, E. coli e\r\nProteusmirabilis foram inoculadas\r\nnos meios indicados pelas normas\r\noficiais e posteriormente inoculados\r\nem amostras fortificadas. Os meios\r\ntestados, tanto em culturas puras\r\nquanto em amostras fortificadas,\r\ntiveram desempenho satisfatório,\r\nmostrando boa seletividade e produtividade,\r\npermitindo que os laboratórios\r\noptem pela combinação de\r\nmeios com melhor performance para\r\nisolamento e identificação de Campylobacter\r\nspp. em amostras naturalmente\r\ncontaminadas.(AU)", "_i": "pt"}]

Evaluation of the Direct and Enrichment Iso 10272 Methods for the Detection of Campylobacter Spp. in Chicken Meat

In 2006, the International Organization for Standardization (ISO) published two standard protocols for the detection and enumeration of Campylobacter spp. in foods: the ISO 10272-2(direct method) and the ISO 10272-1 (enrichment method). The aim of this study was to compare the efficiency of these two methods in the detection of Campylobacter spp. and propose a modification in the enrichment method. Compared with the enrichment method, the direct method yielded a higher number of positive results for Campylobacter spp. and, consequently, presented higher sensitivity percentage. The isolation of Campylobacter spp. was more difficult when 10 mL of rinse was used in the enrichment method, which is currently recommended by the ISO protocol. Therefore, different rinse volumes were tested (2.5 and 5 mL). The most efficient recovery of Campylobacter spp. occurred when 2.5 mL of rinse were used in the enrichment method, most likely due to a lower number of microbial contaminants than that present in the 5 or 10 mL rinses. The proposed modification of the enrichment method will contribute to the food analysis by improving the detection of Campylobacter spp. in chicken carcass.(AU)

Evaluation of the Direct and Enrichment Iso 10272 Methods for the Detection of Campylobacter Spp. in Chicken Meat

In 2006, the International Organization for Standardization (ISO) published two standard protocols for the detection and enumeration of Campylobacter spp. in foods: the ISO 10272-2(direct method) and the ISO 10272-1 (enrichment method). The aim of this study was to compare the efficiency of these two methods in the detection of Campylobacter spp. and propose a modification in the enrichment method. Compared with the enrichment method, the direct method yielded a higher number of positive results for Campylobacter spp. and, consequently, presented higher sensitivity percentage. The isolation of Campylobacter spp. was more difficult when 10 mL of rinse was used in the enrichment method, which is currently recommended by the ISO protocol. Therefore, different rinse volumes were tested (2.5 and 5 mL). The most efficient recovery of Campylobacter spp. occurred when 2.5 mL of rinse were used in the enrichment method, most likely due to a lower number of microbial contaminants than that present in the 5 or 10 mL rinses. The proposed modification of the enrichment method will contribute to the food analysis by improving the detection of Campylobacter spp. in chicken carcass.