Obtenção de compostos fenólicos pelo processo biotecnológico promovido por microorganismos endofíticos e resíduos de frutas tropicais

Abstract

Endophytic microorganisms have received attention from the food, chemical and pharmaceutical industries due to the enormous potential of producing biologically active substances with antioxidant, antiallergic and anti-inflammatory activity. The application of agricultural residues in bioprocesses has been highlighted as a secondary source of energy in fermentative processes. Achachairu (Garcinia humilis), araçá-boi (Eugenia stipitata) and bacaba (Oenocarpus bacaba) are tropical exotic fruits produced in Brazil and have few scientific studies related to their characterization and the possibility of using their residues. Thus, the use of residues of these fruits becomes a viable strategy for the bioconversion of their substrates into bioactive compounds. The present work proposes the isolation of endophytic microorganisms from the cited fruits for the purpose of obtaining bioactive compounds through the process of submerged fermentation. Endophytic isolates of the three fruits were inoculated in synthetic medium (YM) to evaluate the production capacity of phenolic compounds, from the obtained results the microorganism considered most promising in the synthesis of bioactive compounds was selected, which was submitted to a new fermentation using the fruit residues (achachairu, bacaba, araçá-boi and coconut). The bacaba residue was considered the most promising to carry out the biotechnological process and through these definitions (microorganism strain and residue) two experimental designs were carried out (Plackett-Burman and DCCR) to establish the optimal condition for obtaining polyphenols, being this condition pH 8.62 and yeast extract 3.0 g/L. The identification of the isolated microorganisms was performed through the MALDI-TOF MS system. The fermentation was carried out in a bioreactor with a capacity of 5.0 L and in this condition obtained results close to that of the fermentation developed in the workbench. The phenolic compounds produced by the strain, identified as Rhodotorula glutinis, were quantified by the LC MS/MS system, whose values showed a significant increase of 94.06% and 27.81% in relation to the catechin and rutin compounds, respectively. Intracellular production of other compounds such as isohamnetin, luteonin, kaempferol and carotenoids was also observed. Thus, it was concluded that the fermentation of the bacaba residue through the microorganism Rhodotorula glutinis has the potential to obtain phenolic compounds and carotenoids concomitantly and presents a promising scope for the stimulation of new biotechnological studies from fruit residues that are still unexplored, but are capable of promoting the synthesis of compounds with high added value applicable in several industrial sectors.