Development of a selective and differential media for the isolation and enumeration of Bacillus cereus from food samples.
J Appl Microbiol
; 128(5): 1440-1447, 2020 May.
Article
em En
| MEDLINE
| ID: mdl-31867800
ABSTRACT
AIM:
Identification and enumeration of foodborne pathogens in food stuffs are valuable concerns. In the present study, starch-blood-egg yolk-polymyxin B-trimethoprim-ceftazidime (SBYPTC) agar was established to isolate and specify the number of Bacillus cereus in food products. METHODS ANDRESULTS:
The effectiveness of the developed medium in selecting for B. cereus from pure cultures and food matrixes naturally contaminated by high levels of microbiota was estimated, and the results were compared with that of two commercially available MYPA and PMBA media. In pure cultures, there were no significant differences in the recoverability of B. cereus among the three media, however, SBYPTC agar showed a greater exclusivity. To examine SBYPTC performance in food, B. cereus were artificially inoculated into lettuce and potato samples with high background microbiota in two separated experiments. There were no significant differences between MYPA and PEMBA. However, SBYPTC manifested greater selectivity and exclusivity and made the differentiation easier by allowing growth of B. cereus in separated colonies and inhibiting competing microflora.CONCLUSION:
Our results showed that SBYPTC has high selective properties in comparison with MYPA and PEMBA. Thus, it can be considered as a useful tool to monitor the existence and the number of B. cereus in foods especially those contaminated with high levels of microflora. SIGNIFICANCE AND IMPACT OF THE STUDY In the food industry, SBYPTC can be employed for food quality assurance to monitor B. cereus in food products contaminated with high levels of microbiota.Palavras-chave
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Base de dados:
MEDLINE
Assunto principal:
Bacillus cereus
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Meios de Cultura
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Microbiologia de Alimentos
Tipo de estudo:
Prognostic_studies
Idioma:
En
Ano de publicação:
2020
Tipo de documento:
Article