title: An enhanced process for the production of a highly purified extracellular lipase in the non-conventional yeast Yarrowia lipolytica.
abstract: Yarrowia lipolytica LgX64.81 is a non-genetically modified mutant that was previously identified as a promising microorganism for extracellular lipase production. In this work, the development of a fed-batch process for the production of this enzyme in this strain was described. A lipolytic activity of 2,145 U/mL was obtained after 32 h of batch culture in a defined medium supplemented with 10 g/L of tryptone, an enhancer of lipase expression. To maximize the volumetric productivity, two different fed-batch strategies had been investigated. In comparison to batch process, the intermittent fed-batch strategy had not improved the volumetric lipase productivity. In contrast, the stepwise feeding strategy combined with uncoupled cell growth and lipase production phases resulted in a 2-fold increase in the volumetric lipase productivity, namely, the lipase activity reached 10,000 U/mL after 80 h of culture. Furthermore, this lipase was purified to homogeneity by anion exchange chromatography on MonoQ resin followed by gel filtration on Sephacryl S-100. This process resulted in an overall yield of 72% and a 3.5-fold increase of the specific lipase activity. The developed process offers a great potential for an economic production of Lip2 at large scale in Y. lipolytica LgX64.81.
authors.affiliation: Unité de Fermentation, Institut Pasteur de Tunis, 13, place Pasteur, BP 74, 1002, Tunis Belvédère, Tunisia.
authors.forename: Saoussen
authors.initials: S
authors.lastname: Turki
authors.forename: Atef
authors.initials: A
authors.lastname: Ayed
authors.forename: Néjib
authors.initials: N
authors.lastname: Chalghoumi
authors.forename: Frederic
authors.initials: F
authors.lastname: Weekers
authors.forename: Philippe
authors.initials: P
authors.lastname: Thonart
authors.forename: Héla
authors.initials: H
authors.lastname: Kallel