Produção de nanopartículas de zeína para incorporação dos compostos bioativos presentes no extrato do açafrão-da-terra

Abstract

Turmeric (Curcuma longa), belonging to the Zingiberaceae family is a plant rich in bioactive compounds, it acts on a living organism, tissue or cell and has been studied due to its effects as an antioxidant, aid in the treatment of cancer, Alzheimer´s disease, among others. It’s in natura use is not so effective due to its hydrophobicity and little absorption promoted by the organism; so, it has been researched in the encapsulated form. The present work aimed to extract the bioactive compounds from turmeric in a 95:5 (v/v) ethanol: water solvent system and the incorporation into zein nanoparticles by the traditional method of antisolvent precipitation with a double structure of electrostatic deposition in combination with sodium caseinate and chitosan, for possible application in human cells. The hydroethanolic extract was evaluated for antioxidant activity by Fe (II) chelating ability methods, by DPPH and ABTS free radical scavenging, with values of 57.05±0.19%, 94.15±0,08% and 82.46±0.17%, respectively. In addition, the flavonoid content was quantified using aluminum chloride (5548.77±99.51 mg ERU 100g­1) and phenolic compounds by the Folin Ciocalteau method (1737.13±36.57 mg EAG 100g­1). The nanoparticles were analyzed in the DLS equipment for hydrodynamic diameter, zeta potential and polydispersity index and the conditions obtained according to the objective of the work were the mass ratio of 1:0.8 of zein/sodium caseinate; 10:1 (10%) mass of zein/sodium caseinate/extract and the ratio of 0.050% chitosan. The maximum loading capacity and encapsulation efficiency of zein/sodium caseinate/10% turmeric extract nanoparticles were also studied. The results showed that the maximum load capacity of the nanoparticles was around 12% and the encapsulation efficiency around 66%. The hydroethanolic extract, as well as the nanoparticles that contained the extract at 10% by mass of zein/caseinate and zein/caseinate/chitosan, demonstrated cytotoxicity for renal (786­0) and hepatic (HUH7.5) tumor cells, suggesting potential application of Curcuma longa extract as a source of cytotoxic/antiproliferative effects for these cell types.