HIGHLIGHTS

• Multiple forms of lipases can exhibit different properties and applications.

• Mycelium-bound lipases can be helpful for the oleochemical industry.

• All of the multiple forms of lipase were studied and presented hydrolysis activity.

• Partial biochemical characterization of multiple forms of lipases was realized.

• Trichoderma koningii was suggested as a good producer of mycelium-bound lipases.

Abstract

The total cost of processes that use lipases can be reduced by using the mycelium or not purified crude extract with lipolytic activity. These catalysts can be used without complex purification and can show desirable properties to emerging applications like hydrolysis and biotransformation of vegetable oils. To explore the potential of multiple forms of lipases (produced by the same filamentous fungus species), this work investigated intracellular and extracellular lipases produced by Trichoderma koningii (intracellular lipases were never studied), Penicillium spp. F02 (isolated from industrial grease trap) and Aspergillus niger. For this, batch fermentations were conducted for 96h using olive oil as a carbon source. The submerged culture was interrupted with vacuum filtration to isolate the mycelium and crude extract. The lipolytic activities were determined by the hydrolysis method of olive oil. The best results were obtained for intracellular activity with T. koningii (81.5 U/g of dry biomass) and for extracellular activity with A. niger (10.6 U/mL of crude extract). Both were attained in 96h of fermentation. T. koningii showed an accumulation of intracellular lipases and a depreciated extracellular activity in the initial 24 hours, which can be reasonable indications that there is strong retention of lipases in the mycelium. Statistical analysis within the range of 37°C to 44°C associated with pH from 7.8 to 8.0 favored the activity of lipases from T. koningii. All these findings are promising for future studies in the enzymatic synthesis of biodiesel with lipases (intracellular and extracellular) from T. koningii.

Keywords:
Hydrolysis; FFA; Mycelium-bound lipases; Crude extract lipases; Response surface methodology