Improvement of Yarrowia lipolytica lipase production by fed-batch fermentation.

Two different types of fed-batch fermentation were investigated to improve production yields of the Lip2 extracellular lipase in Y. lipolytica mutant-strain LgX64.81 grown in a 20l bioreactor. Compare to batch cultures, culture feeding with the complete medium led to a 2-fold increased lipase production (2016 +/- 76 U ml(-1)) whereas addition of a combination of glucose and olive oil led to a 3-fold increase. The high level of lipase production obtained on glucose media with Y. lipolytica LgX64.81 could be related to its phenotype, i.e., a lower sensibility to glucose catabolite repression due to a modification in the level of HXK1 expression.