Evaluación del estado de desarrollo de hypericum laricifolium sobre metabolitos responsables de actividad antibacteriana utilizando fingerprint cromatográfico

Abstract

The main objective of this study was to investigate the influence of the development phases of Hypericum laricifolium on metabolites responsible for the antibacterial activity against methicillin resistant Staphylococcus aureus (MRSA) using Chromatographic Fingerprint as methodology for modeling. An HPLC-DAD method was developed to separate the components present in H. laricifolium extracts by optimizing the chromatographic conditions, using a factorial design 23. The partial least squares (PLS) method was used to establish a correlation between the antibacterial activity and the chromatographic profiles of H. laricifolium extracts at 254, 280 and 360 nm. A model was constructed using 30 samples with 7501 X variables corresponding to the responses obtained in the UV spectrum at different times; the Y variables consisted of experimental values of inhibitory concentration 50% (IC50) of each extract. Prior to the PLS analysis, the chromatograms were subjected to a pre-treatment of column centering. The PLS model was validated by cross validation; their capacity was evaluated using the correlation parameters (R2) and the root mean square error prediction (RMSEP). The best results were achieved with the 254 nm chromatogram (R2 = 0.90, RMSEP = 2.25). Under these conditions, the optimal number of components was eight. Finally, the Student's T test did not show a significant difference between the antibacterial activities of the young and adult stages of H. laricifolium.