Produção, caracterização e purificação parcial de quitinase produzida por Streptomyces sp. DPUA1581

Abstract

Sustainability is a theme that has been raised steadily in recent years, the production and use of enzymes in an efficient alternative recycling of industrial and agricultural waste. The chitinase acts in the hydrolysis of chitin, the substance can be found in large quantities in the shells of crustaceans. The objective of this research was to select Streptomyces spp. with the greatest potential in the production of chitinase, to characterize the crude and partially purified. For selection we used 30 strains of Streptomyces spp. isolated from lichen in the Amazon region. Parameters such as pH and temperature optima, stability to pH and temperature from the crude enzymatic extract. Partial purification of the enzyme was performed by precipitation in ammonium sulfate in the range of 0-80% and the electrophoresis profile by SDS-PAGE. Streptomyces sp. DPUA1581 chitinase produced by submerged fermentation with 1% of chitin, agitation 150 rpm, at 28 °C for 96 hours. The enzyme characterization showed the best activity in sodium phosphate buffer 100 mM, pH 7.0 and was stable after 180 minutes in all pHs tested. The optimum temperature was 80 °C chitinase, remained stable between 30 and 100 °C for 180 minutes. The activity was enhanced in the presence of Fe2+ (134%), Mn2+ (71%) and the anionic surfactant SDS (59%), however, Pb2+ (99%) and EDTA (62%) inhibited the enzyme function. After fractionation with ammonium sulfate showed the enzymatic extract purification factor equal to 7 and 108% yield. The chitinase produced by Streptomyces sp. DPUA1581 under the conditions described in this work, has a great industrial viability, demonstrating catalytic activity even when subjected to high temperatures for prolonged periods.