摘要

本研究的目的是确定30种燕麦样品和30种巴西市售的亚麻籽的克罗诺氏菌流行率。根据ISO 22964：2017，检测克罗诺杆菌。根据其表型使用Vitek 2.0和抗生素敏感性谱对菌株进行表征。通过靶向dnaG基因的实时PCR，靶向rpoB基因的PCR，靶向cgcA基因的多重PCR和fusA等位基因测序来完成分子表征。 34个样本（56.7％）含有Cronobacter; 19种（63.3％）亚麻籽和15种（50.0％）燕麦。分离株被鉴定为C. sakazakii（n = 18,52.9％），C。dublinensis（n = 7,20.6％），C。turicensis（n = 6,17.7％）和C. malonaticus（n = 3， 8.8％）。将34个Cronobacter分离株分配到11个不同的fusA等位基因中，其中3个是新的（169,170和171）。靶向rpoB基因和cgcA基因的PCR未能鉴定出19个分离株。 7株（20.6％）菌株对四环素具有抗性或中间/抗性，1株（2.9％）菌株对哌拉西林 - 他唑巴坦具有中等抗性。燕麦和亚麻籽中的克罗诺杆菌的存在表明这些食物可能对人类健康构成潜在威胁，特别是在为老年人或免疫抑制的人准备食物时。还应避免不正确地使用这种食物来喂养新生儿（<六个月）。

The aim of this study was to determine the prevalence Cronobacter from 30 samples of oats and 30 of linseeds commercially available in Brazil. The detection of Cronobacter was as according to the ISO 22964:2017. The isolates were characterized according to their phenotypically using Vitek 2.0 and antibiotic susceptibility profile. Molecular characterization was accomplished by real-time PCR targeting dnaG gene, PCR targeting rpoB gene, multiplex-PCR targeting cgcA gene, and fusA allele sequencing. Thirty-four samples (56.7%) contained Cronobacter; 19 (63.3%) of linseeds and 15 (50.0%) of oats. The isolates were identified as C. sakazakii (n = 18, 52.9%), C. dublinensis (n = 7, 20.6%), C. turicensis (n = 6, 17.7%), and C. malonaticus (n = 3, 8.8%). Thirty-four Cronobacter isolates were assigned to 11 different fusA alleles of which three were new (169, 170, and 171). The PCR targeting rpoB gene and cgcA gene failed to identify 19 isolates. Seven (20.6%) strains showed resistance or intermediate/resistance to tetracycline, and one (2.9%) strain had intermediate resistance to piperacilin-tazobactam. The presence of Cronobacter in oats and linseeds indicate that these foods can be a potential threat to human health, particularly when preparing food for elderly or immunosuppressed persons. The incorrect use of this foods for feeding of neonates (

https://www.ncbi.nlm.nih.gov/pubmed/30596968