Encapsulação do ácido fólico e avaliação de sua estabilidade frente a tratamentos térmicos e irradiação UVA

Abstract

Folic acid is a precursor micronutrient of several enzymatic cofactors required for nucleic acid synthesis, amino acid interconversion, DNA methylation, RNA and proteins. Poor folate feeding can lead to various disorders in humans, such as birth defects, heart disease, megaloblastic anemia, Alzheimer's disease, and some types of cancers. In view of the instability of folic acid under different conditions, the purpose of this study was to characterize the fibers and zein capsules prepared by the electrospinning and electrospraying techniques, respectively, and to use them to encapsulate folic acid. Solutions of zein 30% were used for fiber production and 9% for the development of capsules. Folic acid at concentrations of 0.5, 1.0 and 1.5% (w / v) in the polymer solutions was added. The fibers and capsules were evaluated for morphology, diameter, infrared spectroscopy with Fourier transform (FTIR), thermal properties by thermogravimetric analysis (TGA), encapsulation efficiency, thermal stability and light by liquid chromatography high efficiency coupled to mass spectrometry / MS). Solutions of pure zein and folic acid added were able to form uniform fibers and capsules. The mean diameter of the fibers varied from 369 to 702 nm, whereas the capsules were 291 to 339 nm. There was interaction between folic acid and zein observed by FTIR spectra, for both fibers and capsules. The encapsulation of folic acid in the form of fibers or capsules increased its thermal stability, as observed by thermogravimetric curves. Folic acid zein fibers and capsules showed high encapsulation efficiency (> 80%). Pure folic acid showed 70% degradation when exposed to 180 ° C, while fiber or capsule encapsulation provided the stability of folic acid. The photodegradation of pure folic acid was approximately 26%, however, when the vitamin was incorporated into the zein fibers, light stability was observed. The fibers and zein capsules with folic acid developed in this work, presented promising characteristics for application in foods that require thermal processing and exposure to light.