Produção de amilase por Aspergillus flavus isolado a partir da mandioca (Manihot esculenta)

Abstract

In the last four decades thanks to the advancement of biotechnology the enzyme industry has had a rapid and rapid development reaching the threshold we know today. As for amylases, these are among the major classes of industrial enzymes having approximately 25% of the world market for enzymes. Amylolytic enzymes are widely used in biotechnology applications ranging from the food industry, fermentation, textile, paper, among others. Several microbial amylases are diponivies commercially and are used in the hydrolysis of starch, which is a homopolysaccharide formed by glucose units linked by glycosidic bonds. It consists of two polysaccharides, amylose and amylopectin; amylases act to break the glycosidic bonds present in the amylose and amylopectin chains. The objective of this study was the production of amylolytic enzymes from filamentous fungi, through fermentation in the liquid state, aiming at the potential use in biotechnological processes. The amylolytic activity was determined by the method based on the color intensity variation of the iodo-starch complex, called the dextrinizing activity (FUWA, 1954). For dosing, pH 6 and temperature at 50 ° C were used, which parameters were defined as being the ones that the amylases under study had their maximum activity, which was 79.2 U / mL. It was also possible to determine the MichaelisMenten KM constant and the Vmax value, which were 37.2 mg / mL for KM and 4.0 mg / mL for KM, ml / min. for Vmax. As for the identification of the selected isolate, both the morphology and molecular analysis resulted in the Aspergillus flavus species. In the molecular identification, two regions of the DNA were analyzed in the ITS and RSU regions, both with 100% for the species in question.