Ibraheim Hanaa Khaleel, Madhi Khadeeja S, Baqer Gaida K, Gharban Hasanain A J
Department of Microbiology, College of Veterinary Medicine, University of Basrah, Basrah, Iraq.
Department of Microbiology, College of Medicine, University of Basrah, Basrah, Iraq.
Vet World. 2023 Mar;16(3):491-499. doi: 10.14202/vetworld.2023.491-499. Epub 2023 Mar 21.
Probiotics are proven beneficial to health since they enhance immunity against dangerous pathogens and increase resistance to illness. Bacteriocin produced by lactic acid bacteria (LAB), demonstrates a broad inhibitory spectrum and therapeutic potential. This study aimed to isolate LAB-producing bacteriocin and investigate the effect of crude bacteriocin on biofilm from methicillin-resistant (MRSA).
This study used randomly collected 80 white soft local cheeses (40 each from cows and sheep) from different supermarkets in Basrah Province. The obtained samples were cultured and the bacterial suspension of was prepared at 1.5 × 10 cells/mL. The crude bacteriocin extracted from LAB was obtained, and the tube was dried and inverted to detect the biofilm loss at the bottom.
There were 67 (83.75%) LAB isolates. Among 40 milk samples collected directly and indirectly, there were 36 (83.33%). isolates based on conventional bacteriological analysis and biochemical tests. Molecular testing was conducted to identify LAB and MRSA. Depending on genotypic results, the effect of white soft local cheese (cows and sheep) and the amplification results of the gene were detected in 46 LAB isolates from white soft local cheese from cows and sheep. Based on the molecular identification of the , results on determined that only 2 of 36 isolates of carried the . Moreover, there were 26 (86.66%) isolates (MRSA) from samples of raw milk from local markets and subclinical mastitis in cows. The ability of LAB isolates was tested. The effects of bacteriocin production on preventing biofilm growth and formation were investigated. Results demonstrated that bacteriocin has high activity. Microtiter plates applied to investigate the ability of to produce biofilms revealed that all isolates were either weak or moderate biofilm producers, with neither non-biofilm nor strong biofilm producers found among the tested isolates.
Lactic acid bacteria demonstrate a high ability to produce bacteriocin. Crude bacteriocin from LAB has a restrictive effect on biofilms produced by MRSA; thus, it can be used to reduce the pathogenicity of this bacterium.
益生菌已被证明对健康有益，因为它们能增强对危险病原体的免疫力并提高抗病能力。乳酸菌（LAB）产生的细菌素具有广泛的抑制谱和治疗潜力。本研究旨在分离产生细菌素的乳酸菌，并研究粗提细菌素对耐甲氧西林金黄色葡萄球菌（MRSA）生物膜的影响。
本研究随机收集了巴士拉省不同超市的80份白色软质本地奶酪（奶牛和绵羊的各40份）。对获得的样本进行培养，并制备浓度为1.5×10个细胞/毫升的细菌悬液。从乳酸菌中提取粗提细菌素，将试管干燥并倒置以检测底部生物膜的损失情况。
共分离出67株（83.75%）乳酸菌。在直接和间接收集的40份牛奶样本中，有36份（83.33%）。根据传统细菌学分析和生化试验进行菌株鉴定。进行分子检测以鉴定乳酸菌和MRSA。根据基因型结果，在来自奶牛和绵羊白色软质本地奶酪的46株乳酸菌分离株中检测了白色软质本地奶酪（奶牛和绵羊）的效果以及该基因的扩增结果。基于该基因的分子鉴定，对36株该菌分离株的检测结果确定只有2株携带该基因。此外，从当地市场的生鲜乳样本和奶牛亚临床乳腺炎样本中分离出26株（86.66%）MRSA。测试了乳酸菌分离株的能力。研究了细菌素产生对预防生物膜生长和形成的影响。结果表明细菌素具有高活性。用于研究该菌产生生物膜能力的微量滴定板显示，所有分离株要么是弱生物膜产生者，要么是中等生物膜产生者，在测试分离株中未发现无生物膜产生者或强生物膜产生者。
乳酸菌具有很高的产生细菌素的能力。来自乳酸菌的粗提细菌素对MRSA产生的生物膜有抑制作用；因此，它可用于降低该细菌的致病性。
