Elazzazy Ahmed M, Mobarki Mona O, Baghdadi Afra M, Bataweel Noor M, Al-Hejin Ahmed M
Department of Biological Sciences, College of Science, University of Jeddah, P.O. Box 80327, Jeddah 21589, Saudi Arabia.
King Fahad Medical Research Center, King Abdulaziz University, P.O. Box 80216, Jeddah 21589, Saudi Arabia.
Microorganisms. 2024 Mar 25;12(4):651. doi: 10.3390/microorganisms12040651.
The emergence of antibiotic-resistant microorganisms poses a significant threat to human health worldwide. Recent advances have led to the discovery of molecules with potent antimicrobial activity from environmental sources. In this study, fifteen bacterial isolates were obtained from agricultural and polluted soil samples collected from different areas of the cities of Jizan and Jeddah. These isolates were screened for antagonistic activity against a set of human pathogenic bacterial strains. The results showed that two strains, identified as and based on 16S rDNA, synthesized bacteriocin with strong antibacterial activity against Methicillin-resistant (MRSA) ATCC 33591, ATCC 9027, ATCC 14028, carbapenem-resistant , and MRSA 2. To optimize bacteriocin production, the effects of medium composition, incubation period, temperature, and pH were investigated. Nutrient broth and Mueller-Hinton broth were chosen as the optimal original media for bacteriocin production. The optimal incubation period, temperature, and pH were found to be 48 h at 37 °C and 7 pH in and 72 h at 37 °C and 8 pH in . Batch cultures of and were grown in a 10 L benchtop bioreactor, and pH control was found to significantly increase the production of bacteriocin by two-fold compared to uncontrolled conditions. The time course of growth, substrate consumption, pH, and enzyme production were investigated. This study demonstrates the potential of optimizing culture conditions and batch process control to enhance bacteriocin production by spp.
抗生素抗性微生物的出现对全球人类健康构成了重大威胁。最近的进展促使人们从环境来源中发现了具有强大抗菌活性的分子。在本研究中，从吉赞市和吉达市不同地区采集的农业土壤和污染土壤样本中获得了15株细菌分离株。对这些分离株针对一组人类致病细菌菌株的拮抗活性进行了筛选。结果表明，基于16S rDNA鉴定为[具体菌株1]和[具体菌株2]的两株菌株合成了对耐甲氧西林金黄色葡萄球菌（MRSA）ATCC 33591、[具体菌株3]ATCC 9027、[具体菌株4]ATCC 14028、耐碳青霉烯类[具体菌株5]以及MRSA 2具有强抗菌活性的细菌素。为了优化细菌素的生产，研究了培养基组成、培养时间、温度和pH值的影响。营养肉汤和穆勒 - 欣顿肉汤被选为细菌素生产的最佳原始培养基。发现[菌株1]的最佳培养时间、温度和pH值分别为37℃下48小时和pH 7，[菌株2]为37℃下72小时和pH 8。[菌株1]和[菌株2]的分批培养在10 L台式生物反应器中进行，发现与未控制条件相比，pH控制可使细菌素产量显著提高两倍。研究了生长、底物消耗、pH值和酶产生的时间进程。本研究证明了优化培养条件和分批过程控制以提高[具体菌株]细菌素产量的潜力。
