PRODUÇÃO E CARACTERIZAÇÃO DA AMILASE PRODUZIDA POR Rhizopus oryzae ISOLADO DE BANCADA LATERÍTICA

Abstract

Amylases are highly used in industry because of its cost of production and biochemical characteristics. It requires studies that search for filamentous fungal strains focused on production of thermotolerant amylases is desires to increase in industrials applications that request high temperatures. In the present study was isolated filamentous fungi from ironstone outcrops soil, with potential for amylase production. Of the 34 fungi was evaluated and the isolate 21, molecularly identified as Rhizopus oryzae, showed potential for amylase production. After performing the optimization of the amylolytic production of isolated R. oryzae, the highest amylase production obtained was 21.30 U/g of dry substrate of the wheat bran, supplemented with ((NH₄)₂SO₄, MgSO₄*7H₂O e NaNO3) in 55% moisture, at 30°C for 48 hours, increasing of 47.4% compared with initial production. The biochemical characterization of the enzyme produced by isolated R. oryzae show optimal enzymatic activity at pH 5.0 to 75°C with 62,57 U/g of amylolytic activity, residual activity higher than 80% of the enzyme was observed between temperatures from 30°C to 50°C after 1 hour of incubation, and residual activity higher than 65% at pHs range 4.5-9.0 after 24 h of incubation. These characteristics turn this strain of Rhizopus oryzae promising for industrial application in processes that require amylases thermostable. The use of filamentous fungi from the soil of iron outcrops producing amylolytic enzymes is recent and may offer new possibilities for the production and application of enzymes with desirable characteristics for the industry.