Faculty of Engineering and Industrial Sciences, Biotactical Engineering, IRIS, Swinburne University of Technology, Hawthorn, Australia.
Biofouling. 2013 Sep;29(8):939-52. doi: 10.1080/08927014.2013.820826. Epub 2013 Aug 1.
Metallurgical features have been shown to play an important role in the attachment of microorganisms to metal surfaces. In the present study, the influence of the microstructure of as-received (AR) and heat-treated (HT) 1010 carbon steel on the initial attachment of bacteria was investigated. Heat treatment was carried out with the aim of increasing the grain size of the carbon steel coupons. Mirror-polished carbon steel coupons were immersed in a minimal medium inoculated with Escherichia coli (ATCC 25922) to investigate the early (15, 30 and 60 min) and relatively longer-term (4 h) stages of bacterial attachment. The results showed preferential colonisation of bacteria on the grain boundaries of the steel coupons. The bacterial attachment to AR steel coupons was relatively uniform compared to the HT steel coupons where an increased number of localised aggregates of bacteria were found. Quantitative analysis showed that the ratio of the total number of isolated (i.e., single) bacteria to the number of bacteria in aggregates was significantly higher on the AR coupons than the HT coupons. Longer-term immersion studies showed production of extracellular polymeric substances by the bacteria and corrosion at the grain boundaries on both types of steel coupon tested.
冶金特性被证明在微生物附着在金属表面中起着重要作用。在本研究中，研究了收到（AR）和热处理（HT）1010 碳钢的微观结构对细菌初始附着的影响。热处理的目的是增加碳钢试片的晶粒尺寸。将镜面抛光的碳钢试片浸入最小培养基中，接种大肠杆菌（ATCC 25922），以研究细菌附着的早期（15、30 和 60 分钟）和相对较长的时间（4 小时）阶段。结果表明，细菌优先在钢试片的晶界上定植。与 HT 钢试片相比，AR 钢试片上的细菌附着相对均匀，在 HT 钢试片上发现了更多的细菌局部聚集。定量分析表明，在 AR 试片上分离（即单个）细菌的总数与聚集细菌的数量之比明显高于 HT 试片。长期浸泡研究表明，两种类型的钢试片上的细菌都产生了细胞外聚合物物质，并在晶界处发生了腐蚀。
