Avaliação da eficiência de pré-tratamentos físicos e enzimáticos para processamento de biomassa de microalgas

Abstract

The costs involved in production processes based on microalgae are substantially high, due to the lack of appropriate technologies to have access to their fractions of proteins, carbohydrates and lipids, since the cell wall and membrane constitute a barrier to the release of these compounds. intracellular. Thus, it is necessary to improve and increase the efficiency of the cell disruption step, since this is a fundamental pre-treatment for the later stages of biomass processing. Therefore, the objective of the present work was to evaluate physical and enzymatic pre-treatments in the disruption of the cell wall of microalgae. Manual grinding, ultrasound, microwave and enzymatic hydrolysis were the treatments tested in a simple and combined way. Commercial enzymes were used in the biological pretreatment as a positive control and enzymes produced in the laboratory by the solid-state fermentation (SSF) process, where a crude cellulase extract with an activity of 0.03 U/ml by the C1 fungus (genus and species unidentified), and a crude extract of pectinases with an activity of 1.74 U/ml, produced by the fungus Aspergillus niger (MAR). The enzymatic hydrolysis of the Chlorella vulgaris biomass was carried out using a mixture of the two enzymatic types and, at least, one physical method of cell disruption. The highest efficiencies achieved ranged from 32.94 to 40.1% over a period of 1 to 2 hours. The results pointed to enzymatic hydrolysis and ultrasound as promising pre-treatment methods and demonstrated that the combination of physical and biological pre-treatments potentiates cell disruption and facilitates the exploration of products from microalgaeous biomass.