STANDARDIZATION OF THE CULTIVATION OF THE ISOLATED FILAMENTOUS FUNGUS A4 FOR LIPASE PRODUCTION / PADRONIZAÇÃO DO CULTIVO DO FUNGO FILAMENTOSO ISOLADO A4 PARA A PRODUÇÃO DE LIPASES

Abstract

Lipases are produced by microorganisms to form an important biotechnological group of enzymes with different properties and specificities. Among the lipase-producing microorganisms are the filamentous fungi, which are abundant and widespread in nature. Because of their catalytic versatility, lipases are highly commercialized, being applied mainly in the production of detergents, food, animal feed, paper and cellulose, pharmaceutical and biodiesel industries. This work sought to select a filamentous fungus that produces lipases and optimize the conditions for cultivation so as to increase lipolytic activity. Initially, 21 filamentous fungi were grown in a solid medium for lipases for four days in a bacteriological incubator at 30 oC. The fungus with the largest halo representing lipase activity was incubated in five different submerged media at 30 oC for eight days, and the lipase activity of crude extracellular enzyme extracts was evaluated every 24 hours. After defining the culture medium, its composition was varied, analyzing different sources of nitrogen, salt solutions, the influence of the initial pH of the medium and the carbon source. The isolated fungus, identified as A4, exhibited promising lipase synthesis in Khanna submerged culture medium containing urea, peptone and KNO 3 as the nitrogen source, Vogel salts solution, initial pH of 4.5 and cotton oil as a carbon source. This work demonstrated the importance of standardizing chemical conditions for the growth and production of lipases from filamentous fungi, thereby contributing to a greater understanding of the lipases produced by the selection of the fungus with a potential for enzyme production.