A simplified and cost-effective enrichment protocol for the isolation of Campylobacter spp. from retail broiler meat without microaerobic incubation
A simplified and cost-effective enrichment protocol for the isolation of Campylobacter spp. from retail broiler meat without microaerobic incubation
复制标题
用于分离弯曲杆菌属的简化且经济高效的富集方案。
作者：
P. Zhou;S. K. Hussain;M. Liles;C. Arias;S. Backert;J. Kieninger;O. Oyarzabal
为了简化从零售肉鸡肉中分离弯曲杆菌的方法，我们采用非配对样本设计评估了108份样本（胸肉和大腿肉）。根据当前参考方案的建议，在好氧条件下（子样品A）培养富集液，并在微氧条件下（子样品M）进行比较。传感器用于测量肉汤中的溶解氧（DO）和用于富集的袋顶空间中的氧（O2）百分比。采用多重PCR技术对弯曲杆菌分离物进行鉴定，并采用脉冲场凝胶电泳（PFGE）进行分型。利用核糖体基因间间隔分析（RISA）和变性梯度凝胶电泳（DGGE）对亚样品M和A富集48 h后的细菌群落进行了研究。结果A和M的弯曲杆菌阳性亚样数在所有样本合并时（P = 0.81）和按产品分析时（乳房：P = 0.75，大腿：P = 1.00）相似。氧气传感器显示，在整个孵育过程中，肉汤中的DO值约为6 ppm，头部空间中的O2值为14-16%。PFGE显示，从亚样本A和m中获得的分离物在大多数样本中具有高度的基因组相似性。RISA和DGGE结果显示，细菌种群存在很大的差异，这可能归因于样本间的差异，而不是富集条件（好氧或微氧）。这些数据还表明，目前的采样方案尚未优化，无法确定零售锅肉中弯曲杆菌阳性样本的真实数量。结论浓缩肉汤中DO的降低是自然实现的。该方法可作为从零售肉鸡肉中分离弯曲杆菌的参考方法。
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.
DOI：
10.1073/pnas.86.1.232
发表时间：
1989-01-01
影响因子：
11.1
作者：
SHEFFIELD, VC;COX, DR;MYERS, RM
通讯作者：
MYERS, RM