Determinação dos nucleotídeos inosina 5’monofosfato (5’imp) e guanosina 5’ monofosfato (5´gmp) em extrato industrial de levedura utilizando a quimiometria e a espectrofotometria

Abstract

It has being proposed in this paper, a spectrophotometric method to determine simultaneously the compounds Inosine 5 'monophosphate (5'IMP) and guanosine 5' monophosphate (5'GMP) in extracts of dry yeast (final product) and process samples using UV-Vis spectrophotometry technique combined with chemometric tools. Nowadays, 5’IMP and 5’GMP can be determined by chromatographic methods which have high operational costs (equipment, consumables and maintenance) and require more time due to the time spent in obtaining the results. Thus, developing methods that provide a fast quantification of compounds at a lower cost is important from the industrial point of view, mainly regarding processes control. The 5’IMP and 5’GMP have absorption wavelength very close (248 and 253nm, respectively), with UV-Vis spectrum overlap. Pirouette software version 4.5 was used to apply chemometric tools, using chromatographic results for the calibration of the regression models. The experimental procedure was based in dilution of the samples and obtaining spectra in the range of 200 to 350 nm. Exploratory analysis was applied from the PCA (Principal Component Analysis) and method of calibration PLS (Partial Least Squares). Three types of pre-processing were used to calculate the PLS models: normalization of the spectrum, first derivative and centering the datas. The calibrating models were validated with different samples from the ones used in the models. The proposed method sets up a simple and low cost strategy to identify the compounds 5’IMP and 5’GMP derivatives from yeast samples increasing the process assertivity, and company productivity.