Produção de amilase em farelo de milho por fermentação semissólida.

Abstract

The acceptance of enzymes by the feed industry has been increasing because of the increase of knowledge about its functions and properties. The main purpose of using enzymes in the diet of the birds and to improve the efficiency of poultry production through better use of the ration, by increasing the digestibility of the food to reduce the loss of nutrients by feces, and it is possible the use of alternative foods without affecting the performance of these animals. This work's purpose was produce fungal amylolytic enzymes by fermentation process in semi-solid state (SSF), using as agent the fungus Aspergillus niger mutant CCT 0916, applying as substrate corn bran, waste processing industrial dry corn, consisting of bark, and germ portions of grits (a small fraction of the endosperm), aiming observe the potential of this substratum as enzyme producer and their action to hydrolyze com bran to be used in animal ration. Was used as tool the methodology of factorial experimental design 22, in order to verify the effects of moisture and concentration parameters of the nitrogen source in the fermentation process. Was accomplished the physic-chemical characterization of the substratum in order to know important parameters for the SSF process such as: particle size, pH, ash, moisture, ° Brix, reducing sugars, starch, cellulose, protein and pectin. The kinetic monitoring show that the best amylase's production conditions were reached in 52 hours of fermentarion with initial moisture conditions of 41% (b.u) and without the nitrogen source addition, obtaining an enzyme activity of 346.83 U / g of fermentative environment. The response surface revealed the bigger activity values were obtained when decreasing the initial moisture independent of the concentration of nitrogen. The study of the hydrolysis of com bran with the enzyme extract has shown that the enzymes perform breaking the polymer chain of starch, making it a less complex structure, having a potential supplementation in the diets of monogastric animals by better availability of nutrients in the ration.