title: Isolation of a lipase-secreting yeast for enzyme production in a pilot-plant scale batch fermentation.
abstract: The production of lipase by twenty-nine yeasts isolated from the phylloplane of Hibiscus rosa-sinensis was evaluated. The highest lipase producers were Pseudozyma hubeiensis HB85A, Debaryomyces occidentalis-like HB83 and Cryptococcus sp. HB80. P. hubeiensis HB85A batch fermentations were carried out in a bioreactor and lipase production improved 3.2-fold as compared to flask submerged cultures. The production process was significantly reduced from 48 h (in flasks) to 18 h (in the bioreactor). The better hydrolytic activity was achieved with C16 p-nitrophenyl ester. Maximal activity was observed at pH 7.0, the optimum temperature was 50 degrees C at pH 7.0 and the enzyme was stable at 30 and 40 degrees C. The lipolytic activity was stimulated by Mg(2+), K(+) and Ba(2+) salts and EDTA and slightly inhibited by Ca(2+) salts. Non-ionic detergents such as Triton X-100, Tween 80 and Tween 20 strongly stimulated lipase activity, whereas SDS inhibited it. The lipase was stable in iso-octane and hexane at 80%.
authors.affiliation: Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Rio Grande do Sul, Brazil.
authors.forename: Roberta
authors.initials: R
authors.lastname: Bussamara
authors.forename: Alexandre Meneghello
authors.initials: AM
authors.lastname: Fuentefria
authors.forename: Eder Silva
authors.initials: ES
authors.lastname: de Oliveira
authors.forename: Leonardo
authors.initials: L
authors.lastname: Broetto
authors.forename: Michaela
authors.initials: M
authors.lastname: Simcikova
authors.forename: Patrícia
authors.initials: P
authors.lastname: Valente
authors.forename: Augusto
authors.initials: A
authors.lastname: Schrank
authors.forename: Marilene Henning
authors.initials: MH
authors.lastname: Vainstein
mesh_terms: D001420:Bacteria, Aerobic / Q000145:classification / Q000302:isolation & purification* / Q000378:metabolism*; D019149:Bioreactors / Q000382:microbiology*; D005285:Fermentation; D008049:Lipase / Q000302:isolation & purification* / Q000378:metabolism*; D010865:Pilot Projects; D013045:Species Specificity
chemical_list: D008049:Lipase