Produção de etanol de segunda geração em cultura única do fungo endofítico Botrytis sp tendo como substrato o papel filtro

Abstract

The development of new technologies for the production of ethanol from the great availability of lignocellulosic materials, second generation ethanol, is very important due to the climatic problems that occur worldwide and the growth of the country's economy, it shows to be promising due to the use of available and low-cost biomass in the transformation into na energy product with a low level of environmental pollution. In addition to being able to benefit the ethanol production chain, with possibilities even for international commercialization. Aiming at a system that uses the available biomass together with microorganisms for cheapness and simplicity in the production of second generation ethanol. The fungus Botrytis sp proved to be attractive for the production of second generation ethanol due to the ability to degrade cellulosic matter, producing fermentable sugars and ethanol in a single stage of cultivation. Initially, the fungus was grown in a medium with chopped filter paper (20 g / L) in English potato broth (200 g / L) (BP medium) at room temperature and 113 rpm, to evaluate the production of ethanol in 4 weeks. However, the fungus was shown to have a slow fermentation process, producing low concentrations of ethanol in mild conditions. In order to advance this topic and make the production of second generation ethanol more efficient, it was recommended to study the conditions and parameters of crops. In this way, the following checks were made to identify the best condition: need for supplementation of salts in the medium, closed or semi-open system, possibility of a second fermentation with commercial yeast Saccharomyces cerevisiae from the culture broth (at 35 ° C, without stirring, closed, for 48 h) and temperature influence at 35 ° C, all were done in BP medium at 160 rpm for 10 days. Analyzes of alcohol content and total reducing sugar were made using spectrophotometric methods. The best result was in the BP medium without salt supplementation, closed, at 35 ° C and 160 rpm, producing 2,841 g / L of ethanol. The possibility of a second fermentation with yeast was satisfactory, generating a maximum average concentration of 3.66 g / L of ethanol from the hydrolyzed broth fermented by Botrytis sp under the conditions “closed, without salts, at room temperature, 160 rpm”, however , the best fermentative yield with 95.52% was with a second fermentation of the fermented hydrolyzate from Botrytis sp in the same condition, however "semi-open".