Department of Botany and Microbiology, Faculty of Science, Zagazig University, Zagazig 44519, Egypt.
Department of Sciences, King Khalid Military Academy, Riyadh 11495, P.O. Box 22140, Saudi Arabia.
Molecules. 2020 Oct 7;25(19):4583. doi: 10.3390/molecules25194583.
Bacterial outbreaks caused by () are interesting due to the existence of multidrug resistant (MDR) isolates. Therefore, there is a need to develop novel ways to control such MDR . In this study, some natural agents such as honey bee (HB), extracts of either seeds (MSE), or leaves (MLE) and essential oils of garlic, clove, and moringa were studied for their inhibitory activity against this pathogen. About 100 food samples including beef luncheon ( = 25), potato chips ( = 50), and corn flakes ( = 25) were investigated for possible pollution with the bacteria. The isolated bacteria suspected to belong that grew well onto Baird-Parker agar (Oxoid) and shiny halo zones and positive coagulase reaction were selected and identified by API-Kits; all of them that were approved belong to (18 strains). The sensitivity of the obtained 18 bacterial strains to 12 antibiotics were evaluated; all of them were resistant to ofloxacin; however, other antibiotics tested showed variable results. Interestingly, the No. B3 isolated from beef luncheon was resistant to10 antibiotics out of 12 ones tested. Multiple antibiotic resistance index (MAR) of this strain was about 83.3%. Therefore, its identification was confirmed by sequencing of a 16S rRNA gene which approved a successful biochemical identification carried out by API Kits and such strain was designated LC 554891. The genome of such strain appeared to contain gene encoding methicillin resistance; it was found to contain and that encode α-blood hemolysis, β-blood hemolysis, toxic shock syndrome gene, and fibrinogen-binding protein gene, respectively. In addition, the virulence factors viz. encoding enterotoxins were detected in the DNA extracted from B3 strain. Aqueous extract of seeds (MSE) showed inhibitory activity against LC 554891 better than that obtained by tetracycline, essential oils or HB. Minimum inhibitory concentration (MIC) of MSE was 20µg/mL. Instrumental analysis of MSE showed 14 bioactive chemical compounds. Combinations of both MSE and tetracycline showed distinctive inhibitory activity against LC 554891 than that obtained by either tetracycline or MSE singly.
由 （）引起的细菌爆发很有趣，因为存在多药耐药（MDR）分离株。因此，需要开发新的方法来控制这种 MDR 。在这项研究中，研究了一些天然剂，如蜜蜂（HB）、种子（MSE）或叶子（MLE）提取物以及大蒜、丁香和辣木的精油，以研究它们对这种 病原体的抑制活性。大约 100 种食品样本，包括牛肉午餐肉（=25）、薯片（=50）和玉米片（=25），被调查是否可能受到 细菌的污染。从 Baird-Parker 琼脂（Oxoid）上生长良好、有闪亮晕圈和阳性凝固酶反应的疑似 细菌被选择并通过 API 试剂盒鉴定；所有被鉴定为 （18 株）的细菌都属于 。用 12 种抗生素评估获得的 18 株 细菌对 12 种抗生素的敏感性；所有菌株均对氧氟沙星耐药；然而，其他测试的抗生素则显示出不同的结果。有趣的是，从牛肉午餐肉中分离出的 3 号菌株对 12 种测试抗生素中的 10 种具有耐药性。该菌株的多重抗生素耐药指数（MAR）约为 83.3%。因此，通过测序 16S rRNA 基因对其进行了确认，该基因证实了 API 试剂盒成功进行的生化鉴定，该菌株被指定为 LC 554891。该菌株的基因组似乎含有编码耐甲氧西林的 基因；它被发现含有 基因和 基因，分别编码 α-血液溶血、β-血液溶血、中毒性休克综合征基因和纤维蛋白原结合蛋白基因。此外，在从 3 号菌株提取的 DNA 中检测到了 编码肠毒素的毒力因子。种子（MSE）的水提取物对 LC 554891 的抑制活性优于四环素，优于精油或 HB。MSE 的最小抑菌浓度（MIC）为 20µg/mL。MSE 的仪器分析显示了 14 种生物活性化合物。MSE 与四环素的组合对 LC 554891 的抑制活性明显优于单独使用四环素或 MSE。
