Balmages Ilya, Liepins Janis, Zolins Stivens, Bliznuks Dmitrijs, Lihacova Ilze, Lihachev Alexey
University of Latvia, Institute of Atomic Physics and Spectroscopy, Riga, Latvia.
University of Latvia, Institute of Microbiology and Biotechnology, Riga, Latvia.
Biomed Opt Express. 2021 Feb 24;12(3):1609-1620. doi: 10.1364/BOE.416456. eCollection 2021 Mar 1.
In this study, an optical contactless laser speckle imaging technique for the early identification of bacterial colony-forming units was tested. The aim of this work is to compare the laser speckle imaging method for the early assessment of microbial activity with standard visual inspection under white light illumination. In presented research, the growth of bacterial colonies on the solid medium was observed and analyzed. Both - visual examination under white light illumination and laser speckle correlation analysis were performed. Based on various experiments and comparisons with the theoretical Gompertz model, colony radius growth curves were obtained. It was shown that the Gompertz model can be used to describe both types of analysis. A comparison of the two methods shows that laser speckle contrast imaging, combined with signal processing, can detect colony growth earlier than standard CFU counting method under white light illumination.
在本研究中，测试了一种用于早期识别细菌菌落形成单位的光学非接触式激光散斑成像技术。这项工作的目的是将用于微生物活性早期评估的激光散斑成像方法与白光照明下的标准目视检查进行比较。在本研究中，观察并分析了固体培养基上细菌菌落的生长情况。进行了白光照明下的目视检查和激光散斑相关性分析。基于各种实验以及与理论Gompertz模型的比较，获得了菌落半径生长曲线。结果表明，Gompertz模型可用于描述这两种分析类型。两种方法的比较表明，结合信号处理的激光散斑对比度成像比白光照明下的标准CFU计数方法能更早地检测到菌落生长。
