TEMPORAL VARIATION OF THE TOTAL PHENOLIC COMPOUNDS CONCENTRATION IN Vochysia divergens Pohl. (VOCHYSIACEAE) LEAVES IN THE BRAZILIAN PANTANAL
ABSTRACT The total phenol concentration present in Vochysia divergens Pohl. (Vochysiaceae) leaves in the Pantanal was analyzed. Work was carried out between September/2012 and June/2013 which is made up by the dry season (September/2012), the beginning of the rising water (December/2012), the high water (March/2013) followed by the receding water period (June/2013). For the purpose of the research fifteen trees were selected, five from each sample area. The phenolic content in the leaves was obtained from the samples which were dried, steeped with ethanol: water and centrifuged. The extract was used to determine the concentration of total phenols using the Folin-Ciocalteu spectrometric method. There was no difference among the sampling areas; however the values were different in relation to seasonal periods. The lowest concentration was recorded in the dry season (young leaves) increasing gradually at the beginning of the rising water, with higher levels at the end of high water and receding water season. The highest concentration of phenols occurred during the receding water period (end of the life cycle of V. divergens leaves), followed by high and rising water periods. The increase in phenol concentration is associated with the Pantanal flood cycle, and related to the phenology of the V. divergens leaves.