Bacteria species identification by the statistical analysis of bacterial colonies Fresnel patterns.

Optics Express (Impact Factor: 3.55). 05/2013; 21(9):11322-37. DOI: 10.1364/OE.21.011322
Source: PubMed

ABSTRACT It was demonstrated that statistical analysis of bacteria colonies Fresnel patterns recorded in the optical system with converging spherical wave illumination is suitable for highly effective bacteria species classification. The proposed method includes Fresnel patterns recording followed by image processing and the statistical analysis based on feature extraction, feature selection, classification and classification performance methods. Examination performed on various bacteria species (Salmonella enteritidis, Staphylococcus aureus, Staphylococcus intermedius, Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa and Citrobacter freundii) revealed that the proposed method achieved very high accuracy of over 98%.

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    ABSTRACT: The challenge of developing fast and trustworthy method for bacteria identification has been taken by many research groups from all around the world but only two decided to develop methods based on the statistical analysis of forward light scattering on bacterial colonies grown on solid nutrient media. Optical methods contrary to other techniques offer many advantages such as non-destructive and non-contact bacteria identification, which allows application of different method on the same sample if identification confirmation is required e.g. in medical diagnostic procedures. Both mentioned above methods use dedicated optical systems for recording diffraction patterns of the bacterial colonies, construct set of numerical features calculated from the patterns and use statistical analysis for identification of unknown samples. The methods use different optical systems, different numerical features and different statistical analysis workflows and therefore obtain different results. In this chapter we will present a brief comparison of these two methods and a more detailed description of the one developed in our group.
    12/2013: pages 711-721; , ISBN: 978-84-939843-9-7
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    ABSTRACT: Two-dimensional angle-resolved light scattering maps of individual rod-shaped bacteria are measured at the single-cell level. Using quantitative phase imaging and Fourier transform light scattering techniques, the light scattering patterns of individual bacteria in four rod-shaped species (Bacillus subtilis, Lactobacillus casei, Synechococcus elongatus, and Escherichia coli) are measured with unprecedented sensitivity in a broad angular range from -70° to 70°. The measured light scattering patterns are analyzed along the two principal axes of rod-shaped bacteria in order to systematically investigate the species-specific characteristics of anisotropic light scattering. In addition, the cellular dry mass of individual bacteria is calculated and used to demonstrate that the cell-to-cell variations in light scattering within bacterial species is related to the cellular dry mass and growth.
    Scientific reports. 01/2014; 4:5090.


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Jun 1, 2014