Abstract A simple procedure has provided detection and screening of oil-degrading bacteria using optical microscopy. A 100 µm crude-oil droplet was injected at the bottom of and attached onto a transparent Petri dish pre-filled with mineral salt medium. After pipetting microbes into the Petri dish, we observed the interactions between the bacteria and the oil drops. As oil-degrading-bacteria (UltraTech microbes) were consuming components of the oil drops and forming biofilms, the original perfectally spherical shaped oil drop became irregular and the size of the oil drop also varied, whereas non-oil-degrading bacteria changed neither the size nor shape of the oil drops. The surface hydrophobicity and the initial motility of bacteria play essential roles in microbial oil degradation, as the oil-degrading bacteria are more surface hydrophobic than the non-oil-degraders, and high initial motilities were accompanied with high degradation rates. This assay provided direct visualizations of the interactions between oil-degrading bacteria and oil drops, and can be used as a quick screening assay when processing a large number of bacteria strains for potential oil degraders.

中文翻译：

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石油降解和生物膜形成的直接可视化，用于筛选原油降解细菌

摘要 一个简单的程序提供了使用光学显微镜检测和筛选油降解细菌的方法。一个 100 µm 的原油液滴被注入到预先填充有矿物盐介质的透明培养皿的底部并附着在其上。将微生物移入培养皿后，我们观察了细菌和油滴之间的相互作用。由于油降解菌（UltraTech 微生物）消耗油滴的成分并形成生物膜，原来完美球形的油滴变得不规则，油滴的大小也发生了变化，而非油降解细菌并没有改变油滴的大小和形状。细菌的表面疏水性和初始运动性在微生物油降解中起着至关重要的作用，由于油降解细菌比非油降解细菌具有更强的表面疏水性，并且高初始运动性伴随着高降解率。该测定提供了油降解细菌和油滴之间相互作用的直接可视化，并且在处理大量细菌菌株以寻找潜在的油降解剂时可用作快速筛选测定。