Celulases para produção de etanol de segunda geração

Abstract

Ethanol produced from renewable raw materials arises as a substitute source of fossil fuels, which allows the realization of a biotechnological process with less environmental impact. The use of lignocellulosic biomass to bioproduction has become vital to the economy due to their renewable nature, abundance and low cost. The lignocellulosic residues (bagasse and straw) from the sugarcane are abundant sources of carbohydrates and their bioconversion has received great attention. Such residues are formed by: cellulose, hemicellulose and lignin. A study of the lines is the hydrolysis of the residues, which can be acid or enzyme, in order to obtain fermentable sugars. Enzymatic hydrolysis is the most used to have lower glucose degradation rates, lower formation of byproducts inhibitors and to present good yields. The conversion of cellulosic component of such waste biomass, glucose, requires the use of cellulolytic enzymes. The potential cellulases assume that the emerging industry bioenergy and bioproducts becomes a motivation for the development of improved enzyme preparations for hydrolysis of cellulose. However, a major difficulty in the implementation of a biomass bioconversion process is the high cost and low specific activity of the enzymes necessary for the saccharification of cellulose. One way to make the process economically viable immobilized cellulase is such that the catalytic properties are maintained. Immobilization is the enzyme confinement in a solid support for reuse of the biocatalyst.