Zhang Ming, Yang Fan, Pasupuleti Sasikiran, Oh Jun Kyun, Kohli Nandita, Lee I-Syuan, Perez Keila, Verkhoturov Stanislav V, Schweikert Emile A, Jayaraman Arul, Cisneros-Zevallos Luis, Akbulut Mustafa
Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX 77843-3122.
Department of Chemistry, Texas A&M University, College Station, Texas 77943-3144.
Int J Food Microbiol. 2014 Aug 18;185:73-81. doi: 10.1016/j.ijfoodmicro.2014.05.019. Epub 2014 Jun 2.
This work deals with adhesion of Escherichia coli O157:H7 and Salmonella enterica subsp. enterica serovar Typhimurium LT2 (S. Typhimurium LT2) on polyethylene glycol (PEG) coated tomato surfaces. PEG coating was characterized by water contact angle technique, scanning electron microscopy, and secondary ion mass spectrometry. It was shown that PEG films could physisorb on the tomato surfaces after the oxygen plasma treatment, which made some outermost layers of the surfaces hydrophilic. Bacterial adhesion on PEG coated tomato surface was studied by standard plate count, fluorescence microscopy, and scanning electron microscopy techniques. Fully covered PEG film reduced the bacterial attachment 90% or more in comparison to the bare tomato surface. The degree of bacterial attachment decreased exponentially with increasing PEG coverage. When desired, PEG film could be removed by rinsing with water. Overall, this work demonstrates the proof-of-concept that an ultrathin film of polyethylene glycol may be used to effectively inhibit the attachment of pathogenic bacteria on tomato surfaces.
本研究探讨了大肠杆菌O157:H7和肠炎沙门氏菌肠炎亚种鼠伤寒血清型LT2（鼠伤寒沙门氏菌LT2）在聚乙二醇（PEG）包被的番茄表面的黏附情况。采用水接触角技术、扫描电子显微镜和二次离子质谱对PEG包被进行了表征。结果表明，经氧等离子体处理后，PEG薄膜可物理吸附在番茄表面，使表面的一些最外层具有亲水性。通过标准平板计数、荧光显微镜和扫描电子显微镜技术研究了PEG包被的番茄表面的细菌黏附情况。与裸露的番茄表面相比，完全覆盖的PEG薄膜可使细菌附着减少90%或更多。细菌附着程度随PEG覆盖率的增加呈指数下降。如有需要，可通过水洗去除PEG薄膜。总体而言，本研究证明了聚乙二醇超薄膜可有效抑制病原菌在番茄表面附着的概念验证。
