title: Effect of forced aeration on citric acid production by Aspergillus sp. mutants in SSF.
abstract: Citric acid (CA) is one of the most important products of fermentation in the world. A great variety of agro-industrial residues can be used in solid state fermentation. Aspergillus niger parental strain (CCT 7716) and two strains obtained by mutagenesis (CCT 7717 and CCT 7718) were evaluated in Erlenmeyer flasks and glass columns using citric pulp (CP) as substrate/support, sugarcane molasses and methanol. Best results using glass columns (forced aeration) were found in the fourth day of fermentation: 278.4, 294.9 and 261.1 g CA/kg of dry CP with CCT 7716, CCT 7718 and CCT 7717, respectively. In Erlenmeyer flasks (aeration by diffusion) CA reached 410.7, 446.8 and 492.7 g CA/kg of dry CP with CCT 7716, CCT 7718 and CCT 7717, respectively. The aeration by diffusion improved CA production by the three strains. A data acquisition system specially developed for biotechnological processes analysis was used to perform the respirometric parameters measurement.
authors.affiliation: Bioprocess Engineering and Biotechnology Department, Federal University of Paraná (UFPR), Curitiba, PR, Brazil, cristinelabor@gmail.com.
authors.forename: Cristine
authors.initials: C
authors.lastname: Rodrigues
authors.forename: Luciana P S
authors.initials: LP
authors.lastname: Vandenberghe
authors.forename: Wilerson
authors.initials: W
authors.lastname: Sturm
authors.forename: Dario E A
authors.initials: DE
authors.lastname: Dergint
authors.forename: Michele Rigon
authors.initials: MR
authors.lastname: Spier
authors.forename: Júlio Cesar
authors.initials: JC
authors.lastname: de Carvalho
authors.forename: Carlos R
authors.initials: CR
authors.lastname: Soccol
mesh_terms: D001234:Aspergillus niger / Q000235:genetics* / Q000378:metabolism* / Q000528:radiation effects; D018533:Biomass; D019149:Bioreactors; D001709:Biotechnology; D002849:Chromatography, Gas; D019343:Citric Acid / Q000378:metabolism*; D002957:Citrus / Q000737:chemistry*; D004875:Ergosterol; D005285:Fermentation; D000432:Methanol / Q000378:metabolism; D008965:Molasses; D016296:Mutagenesis; D014466:Ultraviolet Rays
chemical_list: D019343:Citric Acid; D000432:Methanol; D004875:Ergosterol