Jui Afsana Habib, Bhuiyan Mohammad Nazrul Islam, Bhowmik Banasree, Khatun Nazia, Chowdhury Abhijit, Bhuiyan Riyadh Hossen, Kabir Md Alamgir, Rashid Md Mamunur, Bhuiyan Md Habibur Rahman, Afrin Sadia
Institute of Food Science and Technology (IFST), Bangladesh Council of Scientific and Industrial Research (BCSIR), Dr. Qudrat-i-Khuda Road, Dhaka 1205, Bangladesh.
BCSIR Dhaka Laboratories, Bangladesh Council of Scientific and Industrial Research (BCSIR), Dr. Qudrat-i-Khuda Road, Dhaka 1205, Bangladesh.
Access Microbiol. 2024 Aug 1;6(8). doi: 10.1099/acmi.0.000830.v4. eCollection 2024.
Biosurfactants are naturally occurring compounds synthesized by micro-organisms that increasingly attract attention due to both their living area and application in various industries. In this study, we explore and characterize a novel bacterium, strain BDIFST24001, isolated for its ability to produce rhamnolipid biosurfactants, with the aim of facilitating oil remediation processes. The isolation of this bacterium was carried out using Luria-Bertani (LB) broth media from environmental samples collected from oil-contaminated sites in Dhaka City. Screening tests, including the oil spreading method and drop collapse assay, were conducted to identify potential biosurfactant-producing strains, leading to the selection of strain BDIFST24001 based on its favourable performance. Subsequent molecular identification revealed a high similarity of the strain's 16S rRNA gene to , which was corroborated through phylogenetic analysis. Further analysis of the biosurfactant produced by this strain indicated its rhamnolipid nature, as confirmed by FT-IR spectroscopy. The rhamnolipids exhibited promising surface-active properties, including a significant reduction in surface tension and emulsification activity, as evidenced by surface tension measurements and emulsification index assays. Optimization studies revealed that the optimal conditions for rhamnolipid production by strain BDIFST24001 were a temperature of 37 °C, pH 10.0 and salinity of 4 %. The rhamnolipids produced by this strain demonstrated effective oil remediation capabilities, as observed through controlled experiments using petrol oil. The rhamnolipids effectively reduced the surface tension of the oil-water interface, facilitating the dispersion and emulsification of the oil phase in water. Overall, our findings highlight the potential of strain BDIFST24001 as a promising candidate for biosurfactant-mediated oil spill cleanup and environmental remediation efforts.
生物表面活性剂是微生物合成的天然化合物，因其广泛的生存领域和在各行业的应用而越来越受到关注。在本研究中，我们探索并鉴定了一种新型细菌，即BDIFST24001菌株，该菌株因能够产生鼠李糖脂生物表面活性剂而被分离出来，目的是促进油污修复过程。该细菌的分离是使用来自达卡市受石油污染地点采集的环境样本，通过Luria-Bertani（LB）肉汤培养基进行的。进行了包括油扩散法和液滴坍塌试验在内的筛选试验，以鉴定潜在的生物表面活性剂产生菌株，基于其良好的性能选择了BDIFST24001菌株。随后的分子鉴定显示该菌株的16S rRNA基因与[具体菌株]高度相似，这通过系统发育分析得到了证实。对该菌株产生的生物表面活性剂的进一步分析表明其为鼠李糖脂性质，傅里叶变换红外光谱（FT-IR）证实了这一点。鼠李糖脂表现出有前景的表面活性特性，包括表面张力显著降低和乳化活性，表面张力测量和乳化指数测定证明了这一点。优化研究表明，BDIFST24001菌株产生鼠李糖脂的最佳条件是温度37°C、pH 10.0和盐度4%。通过使用汽油进行的对照实验观察到，该菌株产生的鼠李糖脂具有有效的油污修复能力。鼠李糖脂有效地降低了油水界面的表面张力，促进了油相在水中的分散和乳化。总体而言，我们的研究结果突出了BDIFST24001菌株作为生物表面活性剂介导的石油泄漏清理和环境修复工作的有前景候选者的潜力。
