Surface adhesion fermentation for lipase production by mucor griseocyanus

摘要

The lipase production by Mucor griseocyanus was evaluated using surface adhesion fermentation. Plastic particles, covered with fungal biomass, were produced in the first experimental step. Erlenmeyer flasks (250 ml) were used with whey as culture medium, polystyrene foam as support for fungal growth, and olive oil as inducer for lipase activity. Kinetics were monitored during 72 h of culture time. In a second experimental step, an airlift bioreactor was packed with the plastic particles covered withfungal biofilm and used for production of lipases in batch conditions employing whey supplemented with olive oil. Evaluation of operational conditions indicated that the maximum level of activity was obtained at 60 C and at pH 6.0. It was demonstrated that the fungus grown by adhesion on plastic particles produced the highest activity level (133 U L"1) at 60 h, however, fungal biofilms obtained at 72 h of surface adhesion fermentation had a lipolytic activity at 94 U L~(-1). For this reason, under theseculture conditions, the fungal particles were produced and then packed into the airlift bioreactor where the lipase activity was enhanced. Two sequential batches were evaluated using the same particles of polystyrene foam covered by fungal biomass. Thefungal covered particles can be used and reused to produce lipases.