Department of Biotechnology, Universitat Politècnica de València, Camino de Vera s/n, 46022, Valencia, Spain.
Food Microbiol. 2017 Aug;65:279-283. doi: 10.1016/j.fm.2017.02.011. Epub 2017 Mar 10.
Some species of the Arcobacter genus are considered emerging foodborne and waterborne enteropathogens. However, the presence of Arcobacter spp. in vegetables very little is known, because most studies have focused on foods of animal origin. On the other hand, quinolones are considered as first-line drugs for the treatment of infection by campylobacteria in human patients, but few data are currently available about the resistance levels to these antibiotics among Arcobacter species. Therefore, the aim of this study was to investigate the presence and diversity of arcobacters isolated from fresh vegetables such as lettuces, spinaches, chards and cabbages. Resistance to quinolones of the isolates was also investigated. One hundred fresh vegetables samples purchased from seven local retail markets in Valencia (Spain) during eight months were analysed. The study included 41 lettuces, 21 spinaches, 34 chards and 4 cabbages. Samples were analysed by culture and by molecular methods before and after enrichment. By culture, 17 out of 100 analysed samples were Arcobacter positive and twenty-five isolates were obtained from them. Direct detection by PCR was low, with only 4% Arcobacter spp. positive samples. This percentage increased considerably, up 20%, after 48 h enrichment. By polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), 17 out of the 25 isolates were identified as A. butzleri and 8 as A. cryaerophilus. Only two A. butzleri isolates showed resistance to levofloxacin and ciprofloxacin. The sequencing of a fragment of the QRDR region of the gyrA gene from the quinolones-resistant isolates revealed the presence of a mutation in position 254 of this gene (C-T transition). This study is the first report about the presence of pathogenic species of Arcobacter spp. in chards and cabbages and confirms that fresh vegetables can act as transmission vehicle to humans. Moreover, the presence of A. butzleri quinolone resistant in vegetables could pose a potential public health risk.
一些弧菌属物种被认为是新兴的食源性和水源性肠道病原体。然而，关于弧菌属在蔬菜中的存在情况知之甚少，因为大多数研究都集中在动物源性食品上。另一方面，喹诺酮类药物被认为是治疗人类弯曲杆菌感染的一线药物，但目前关于弧菌属对这些抗生素的耐药水平的数据很少。因此，本研究旨在调查从生菜、菠菜、羽衣甘蓝和卷心菜等新鲜蔬菜中分离出的弧菌的存在和多样性。还研究了分离株对喹诺酮类药物的耐药性。从西班牙瓦伦西亚的七个当地零售市场购买了 100 个新鲜蔬菜样本，在 8 个月内进行了分析。研究包括 41 份生菜、21 份菠菜、34 份羽衣甘蓝和 4 份卷心菜。样本在富集前后通过培养和分子方法进行分析。通过培养，在 100 个分析样本中有 17 个为弧菌阳性，从中获得了 25 个分离株。PCR 直接检测的阳性率较低，只有 4%的弧菌属阳性样本。经过 48 小时富集后，这一比例显著增加到 20%。通过聚合酶链反应-限制性片段长度多态性（PCR-RFLP），25 个分离株中有 17 个被鉴定为 A. butzleri，8 个为 A. cryaerophilus。只有 2 个 A. butzleri 分离株对左氧氟沙星和环丙沙星表现出耐药性。对喹诺酮类耐药分离株的 gyrA 基因 QRDR 区的一个片段进行测序，发现该基因第 254 位发生了突变（C-T 转换）。本研究首次报道了在羽衣甘蓝和卷心菜中存在致病性弧菌属物种，并证实新鲜蔬菜可能是人类感染的传播媒介。此外，蔬菜中存在对喹诺酮类耐药的 A. butzleri 可能会对公共健康构成潜在威胁。
