Abstract

The main objective of this study is to highlight the dietary risk of the prevalence of bla_ESBL producing multidrug-resistant Enterobacteriaceae in raw milk, besides evaluating the effect of Artemesia herba-alba and Thymus algeriensis essential oils against bla_ESBL producing Enterobacteriaceae isolates from raw milk. Isolation and molecular identification of ESBL producing Enterobacteriaceae and bla_TEM, bla_SHV, bla_CTX-M genes encoding resistance were investigated by PCR and sequencing. The chemical composition of oils was effectuated by GC/MS. Antibacterial activity was tested by disc diffusion and microdilution methods. Six ceftazidime-resistant Enterobacteriaceae were identified; four of them were confirmed as ESBL producers and were found to be multi-drug resistant. bla_SHV and bla_TEM were found to be having the most dominant gene encoding resistance. The results of GC/MS analysis bestowed 31 and 35 compounds for A. herba-alba and T. algeriensis respectively. Klebsiella pneumonia SB6 (17.04 mm for A. herba-alba and 16.22 mm for T. algeriensis) revealed the highest zones of inhibition. MIC values were 1.56-12.5 mg/mL for both essential oils, while the MBC values were 6.25-25 mg/mL (A. herba-alba) and 12.5-25 mg/mL (T. algeriensis).

摘要

本研究的主要目的是强调生奶中产bla _{ESBL 的}多重耐药肠杆菌科细菌流行的饮食风险，此外还评估了白蒿和阿尔及利亚百里香精油对生奶中产bla _ESBL肠杆菌科细菌的影响. 产ESBL肠杆菌和bla _TEM , bla _SHV , bla _CTX-M的分离及分子鉴定通过PCR和测序研究了编码抗性的基因。油的化学成分由 GC/MS 确定。通过圆盘扩散和微量稀释方法测试抗菌活性。鉴定出6株耐头孢他啶的肠杆菌；其中四人被确认为 ESBL 生产者，并被发现具有多重耐药性。bla _SHV和bla _TEM被发现具有最主要的编码抗性基因。GC/MS 分析结果分别为A. herba-alba和T. algeriensis提供了 31 和 35 个化合物。肺炎克雷伯菌SB6（A. herba-alba为 17.04 mm，A. herba-alba为 16.22 mmT. algeriensis ) 显示出最高的抑制区域。两种精油的 MIC 值为 1.56-12.5 mg/mL，而 MBC 值为 6.25-25 mg/mL（A. herba-alba）和 12.5-25 mg/mL（T. algeriensis）。