Aproveitamento tecnológico dos resíduos da agroindústria de frutos do Cerrado e Caatinga para obtenção de surfactante natural

Abstract

During fruit processing for the production of various products, such as pulps, juices, sweets, jams, and ice creams, residues such as peels and seeds are generated, which are often underutilized. An interesting alternative for the use of these residues is the extraction of bioactive compounds, such as saponins (SAP). SAP exhibit surfactant properties, with emulsifying and foaming capacity, in addition to possessing various biological activities, such as antimicrobial, hypocholesterolemic, hemolytic, antioxidant, and pesticide effects. Although many studies have evaluated the extraction of SAP from different plant sources, no results have yet been published on the potential of residues from the agroindustry of fruits from the Cerrado and Caatinga biomes. In light of this, this study aimed to evaluate the potential of fruit residues from the Cerrado and Caatinga regions of Northern Minas Gerais for the extraction of SAP. In addition, it evaluated and optimized the maceration extraction process from the residues, as well as assessed the functional and biological properties of the extracts with the highest SAP content. The optimized extraction conditions from the residues were: 35 °C for 4 h, with 80% ethanol concentration for macaúba and umbu, and 45 °C for 2.5 h with 80% ethanol for buriti and pequi. Under these extraction conditions, the concentrations of saponins in the extracts from macaúba, umbu, buriti, and pequi residues were 2.58, 2.50, 2.28, and 2.21 mg/mL, respectively. In the evaluation of saponin partitioning in extracts from umbu and macaúba residues using an aqueous two-phase system, no significant effect of the studied variables (system composition and temperature) was observed. The emulsifying and foaming capacity, as well as the stability of these systems, was low. However, these extracts demonstrated antimicrobial activity by inhibiting the growth of Salmonella Typhimurium, Escherichia coli, and Staphylococcus aureus.