Acai pulp and seeds as emerging sources of phenolic compounds for enrichment of residual yeasts (Saccharomyces cerevisiae) through biosorption process

Abstract

In this study, we used the aqueous extract of the acai pulp (APE) and seeds (ASE) as sources of phenolic compounds that were biosorbed in residual S. cerevisiae. In order to provide more accurate results, different nonlinear kinetic and isotherm models were applied to elucidate the interaction between bioactive compounds and residual yeast. The theoretical models demonstrated that the biosorption processes using APE and ASE were multilayer and monolayer types, respectively. In both matrices, the enthalpy variation was negative, indicating an energy release resulting from the biosorption, thus inferring in an exothermic process. The acai seeds showed a high concentration of phenolic compounds, especially flavonoids (30% of total phenolic compounds). The biosorption using residual yeast was effective in recovering about 20% of the total phenolic compounds in APE and more than 60% in ASE, resulting in a low cost matrix rich in proteins and bioactive compounds.