A simplified and cost-effective enrichment protocol for the isolation of Campylobacter spp. from retail broiler meat without microaerobic incubation

BMC Microbiology

Methodology Article

Omar A Oyarzabal¹  Jessica Kieninger¹  Ping Zhou¹  Mark R Liles²  Covadonga R Arias³  Syeda K Hussain⁴  Steffen Backert⁵ 

[1] Department of Biological Sciences, Alabama State University, 1627 Hall Street, Montgomery, AL, USA;Department of Biological Sciences, Life Science Bldg Auburn University, 101 Rouse, AL, USA;Department of Fisheries and Allied Aquacultures, Auburn University, 101 Swindle Hall, AL, USA;Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, AK, USA;University College Dublin, UCD School of Biomolecular and Biomedical Sciences, Science Center West, Belfield Campus, Dublin 4, Ireland;

关键词: Microaerobic Condition;    Enrichment Broth;    True Positive Fraction;    Broiler Meat;    mPCR Assay;   

DOI  :  10.1186/1471-2180-11-175

 received in 2011-05-10, accepted in 2011-08-03,  发布年份 2011

来源: Springer

【 摘 要 】

BackgroundTo simplify the methodology for the isolation of Campylobacter spp. from retail broiler meat, we evaluated 108 samples (breasts and thighs) using an unpaired sample design. The enrichment broths were incubated under aerobic conditions (subsamples A) and for comparison under microaerobic conditions (subsamples M) as recommended by current reference protocols. Sensors were used to measure the dissolved oxygen (DO) in the broth and the percentage of oxygen (O2) in the head space of the bags used for enrichment. Campylobacter isolates were identified with multiplex PCR assays and typed using pulsed-field gel electrophoresis (PFGE). Ribosomal intergenic spacer analyses (RISA) and denaturing gradient gel electrophoresis (DGGE) were used to study the bacterial communities of subsamples M and A after 48 h enrichment.ResultsThe number of Campylobacter positive subsamples were similar for A and M when all samples were combined (P = 0.81) and when samples were analyzed by product (breast: P = 0.75; thigh: P = 1.00). Oxygen sensors showed that DO values in the broth were around 6 ppm and O2 values in the head space were 14-16% throughout incubation. PFGE demonstrated high genomic similarity of isolates in the majority of the samples in which isolates were obtained from subsamples A and M. RISA and DGGE results showed a large variability in the bacterial populations that could be attributed to sample-to-sample variations and not enrichment conditions (aerobic or microaerobic). These data also suggested that current sampling protocols are not optimized to determine the true number of Campylobacter positive samples in retail boiler meat.ConclusionsDecreased DO in enrichment broths is naturally achieved. This simplified, cost-effective enrichment protocol with aerobic incubation could be incorporated into reference methods for the isolation of Campylobacter spp. from retail broiler meat.

【 授权许可】

Unknown   
© Zhou et al; licensee BioMed Central Ltd. 2011. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.