Classification of lactic acid bacteria with UV-resonance Raman spectroscopy.
UV-resonance Raman spectroscopy is applied as a method for the identification of lactic acid bacteria from yogurt. Eight different strains of bacteria from Lactobacillus acidophilus, L. delbrueckii ssp. bulgaricus, and Streptococcus thermophilus were investigated. At an excitation wavelength of 244 nm signals from nucleic acids and proteins are selectively enhanced. Classification was accomplished using different chemometric methods. In a first attempt, the unsupervised methods hierarchical cluster analysis and principal component analysis were applied to investigate natural grouping in the data. In a second step the spectra were analyzed using several supervised methods: K-nearest neighbor classifier, nearest mean classifier, linear discriminant analysis, and support vector machines.
Gaus
K
K
Institut für Physikalische Chemie, Friedrich-Schiller-Universität Jena, Helmholtzweg 4, 07743 Jena, Germany.
Rösch
P
P
Petry
R
R
Peschke
K-D
KD
Ronneberger
O
O
Burkhardt
H
H
Baumann
K
K
Popp
J
J
D016000:Cluster Analysis; D016002:Discriminant Analysis; D005516:Food Microbiology; D007778:Lactobacillus / Q000737:chemistry / Q000145:classification*; D007779:Lactobacillus acidophilus / Q000737:chemistry / Q000145:classification; D048668:Lactobacillus delbrueckii / Q000737:chemistry / Q000145:classification; D025341:Principal Component Analysis / Q000379:methods; D013059:Spectrum Analysis, Raman / Q000379:methods*; D048249:Streptococcus thermophilus / Q000737:chemistry / Q000145:classification; D015014:Yogurt / Q000382:microbiology*