We assessed the ability of Fourier transform infrared spectroscopy (FT-IR) to differentiate three important and morphologically similar <i>Aspergillus</i> species: <i>A. ochraceus</i> and <i>A. westerdijkiae</i>, and <i>A. niger</i>. Fungi were processed by two methods, powdered mycelia and conidiospore-saline solution, and then recorded in a spectrometer. Second derivatives with nine points of smoothing were applied as spectra data pretreatment. Partial least squares regression was used for the species comparison models and a prediction test was used to evaluate the models. The powdered-mycelia methodology correctly identified 100% of the prediction test set to discriminate <i>A. niger</i> from <i>A. ochraceus</i> and <i>A. westerdijkiae</i>; in addition, it had a 86.6% success rate in discriminating <i>A. ochraceus</i> and <i>A. westerdijkiae</i>. This is the first time a study assessed the ability of FT-IR to differentiate <i>A. niger</i>, <i>A. ochraceus</i>, and <i>A. westerdijkiae</i>, and we believe this technique is very promising for classifying and distinguish fungi isolates.
Vol. 8, Iss. 4 Virtual Journal for Biomedical Optics
Sabina Moser Tralamazza, Angela Bozza, João Guilherme Rodenbusch Destro, Jaime Iván Rodríguez, Patricia do Rocio Dalzoto, and Ida Chapaval Pimentel, "Potential of Fourier Transform Infrared Spectroscopy (FT-IR) to Differentiate Environmental Aspergillus Fungi Species A. niger, A. ochraceus, and A. westerdijkiae Using Two Different Methodologies," Appl. Spectrosc. 67, 274-278 (2013)