88D-6 |
Discrimination of E. coli species by fourier transform infrared spectroscopy |
S. SAKHAMURI and J. M. K. Irudayaraj. Department of Agricultural and Biological Engineering, Pennsylvania State University, 109, Agricultural Engineering Building, University Park, PA 16802 Fourier transform infrared spectroscopy can be used to identify microorganisms. Bacterial FTIR spectrum is given by the vibrational properties of all the cell constituents, including fatty acids, proteins, polysaccharides, and nucleic acids. This study attempts to discriminate five different strains of E. coli using Fourier transform infrared (FTIR) spectroscopy that provide rapidity, reliability and routine analysis of many samples. Multivariate statistical methods were applied to extract qualitative information from the mid-infrared spectra and classifying microorganisms. The E. coli species used in this study were K12, JM101, JM 107, HB101, and DH5a. Spectra of bacteria in different concentrations were recorded in the mid-infrared range using the attenuated total reflectance accessory of the Bio-Rad FTS-6000 Fourier transform infrared spectrometer. Predictive models were developed to classify the five different E. coli strains using discriminant analysis. Linear discriminant analysis (LDA) and Canonical variate analysis (CVA) were used to identify the type of E. coli species. An optimum classification of 100% was achieved using LDA. Results demonstrated that FTIR spectroscopy is very competitive and could become a good microbial identification tool.
Session 88D, Food Microbiology: General
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