Síntese e caracterização de materiais de acesso restrito para separação de compostos bioativos provenientes do caldo de fermentação de fungos endofíticos

Abstract

The analysis of organic compounds in complex matrices is a time-consuming, expensive, and often error-prone task. Thus, analytical chemistry has proposed innovative solutions to make this process more efficient and reliable. Following this trend, this work proposed the use of a

Restricted access materials, with magnetic properties, based on carbon nanotubes (M- RACNTs) to be used as a sorbent in the extraction in solid magnetic dispersive phase (MDSPE),

of organic compounds from the fermentation broth of the endophyte Lasiodiplodia sp. The synthesis of the material was performed by functionalizing commercial multiple-walled carbon nanotubes (CNTs) with magnetic nanoparticles (M-CNTs) and by coating the M-CNTs with a

layer of bovine serum albumin (BSA). The studied materials (CNTs, M-CNTs, and M- RACNTs) were characterized using infrared spectroscopy with Fourier transform,

thermogravimetric analysis, and zeta potential. Through physical characterization, it was possible to evaluate the presence of magnetic nanoparticles, as well as the BSA layer. After characterization, the M-RACNTs were then used in MDSPE to obtain organic compounds from the fermentation broth of the endophyte Lasiodiplodia sp. In preliminary studies, the material proved to be a good sorbent, and based on these results, multivariate optimization was performed, through fractional factorial planning, for four independent variables: material mass, adsorption time, solvent volume, and desorption time. The extracts were evaluated by using GC-MS and LC-MS / MS. After the optimization, it was possible to obtain ideal conditions of extraction for a hydrocarbon and two possible derivatives of jasmonic acid. It was concluded that the material has a high potential to be used in the sample preparation process for the extraction of organic compounds from endophytic fungi fermentation broth, since presented a greater pre-concentration compared to the usual technique (liquid-liquid extraction), use of small amount of sample and low consumption of organic solvents.