Resíduo agroindustrial de Agave sisalana como um inovador insumo cosmético antioxidante: avaliação in vitro e in vivo

Abstract

Agave sisalana (sisal) is a plant extensively cultivated in the northeast region to obtain a hard fiber used to produce string and rope. However, only a small portion of the gross weight of sisal leaves is used, and the rest is discarded as residue. This residue has metabolites with potential antioxidant activity in its chemical constitution. In view of this, the objective of this work was, from the residue of A. sisalana, to obtain and characterize a hydroethanolic and a purified absorption, to evaluate the antioxidant potential in vitro and in vivo and to develop a nanoemulsion for carrier fractions to be applied as a cosmetic product antioxidant. From the residue, a recipe rich in polysaccharides (FRE) were received and, from the FRE, another recipe was through ultrafiltration dialysis (FREP). The qualitative composition was evaluated using liquid chromatography coupled to mass spectrometry (LC-MS). Both fractions were evaluated for their antioxidant activity in vitro, using different spectrophotometric techniques, culture medium and in vivo, using the Caenorhabditis elegans model. Furthermore, an experimental factorial design (2³+3PC) was designed to obtain a nanoemulsified system and its stability evaluated. FRE and FREP are mainly composed of terpenoids and O-glycosylated metabolites. FRE showed greater ability to directly inhibit DPPH and ABTS radicals, while FREP showed greater metal chelating activity (Cu2+ and Fe2+). The two fractions promote a protective effect against oxidative stress in 3T3 cells. In C. elegans models, FRE and FREP promoted intracellular reduction of ROS and increased survival representation. The expression of gst-4:GFP was positive for FRE whereas, for FREP, a reduction in expression was observed. The nanoemulsion consisting of 20% oil phase, 5% surfactants and 75% aqueous phase was considered stable for 90 days at different temperatures. The use of sisal residue as a new antioxidant input for the cosmetic industry can bring environmental benefits and contribute to the socioeconomic development of the region.