DETERMINATION OF THE PRODUCTION OF LIPASE BY ASPERGILLUS NIGER IN DIFFERENT CULTURE MEDIUM

Emerson Santos (UNESP); Carolina Manzato Seraphim (UNIARA); Rosemeire Cristina Linhari Rodrigues Pietro (UNESP)

Among the hydrolytic enzymes of interest there are the lipases (glycerol ester hydrolase EC. 3.1.1.3), which are versatile biocatalysts capable of catalyzing different reactions, both in water and in organic media with restricted water content. In their natural environment these enzymes have the function of catalyzes the hydrolysis of triacylglycerides to the corresponding fatty acids and glycerol. Besides metabolic functions, the lipases play an important role in biotechnology, especially in the oil industry and food, and organic synthesis of compounds. In this work were evaluated 2 culture media, as described in literature, for the production of lipase. For this was used an industrial strain of Aspergillus niger grown in solid medium plate containing the potato dextrose agar. After 10 days, it was incubated in 250 mL Erlenmeyer flasks containing 100 mL of culture medium. The incubation occurred in shaker with orbital rotation of 180 rpm and 28^o  C of temperature. After the incubation period, the enzyme extract was filtered to remove biomass. The enzyme activity was measured using the p-nitrophenylpalmitate (pNPP) as substrate. One unit of enzyme activity was expressed as the amount of enzyme required to liberate 1 mmol of r-nitrophenol per minute of reaction. The concentration of proteins was also determined using Lowry method. The results showed that the medium that have higher production showed specific activity 2.75 higher than the second. The main difference between them was the use of olive oil as enzyme inducer in the medium with increased production and Tween 80 in the second medium. Moreover, the medium with best production it was used sucrose as carbon source while the another glucose was utilized. The results are very important because it seeks the improvement of the production of lipases in industrial scale.
Support: FAPESP