title: A mutation of Aspergillus niger for hyper-production of citric acid from corn meal hydrolysate in a bioreactor.
abstract: The properties of the screened mutants for hyper-production of citric acid induced by carbon ((12)C(6+)) ion beams and X-ray irradiation were investigated in our current study. Among these mutants, mutant H4002 screened from (12)C(6+) ion irradiation had a higher yield of citric acid production than the parental strain in a 250-ml shaking flash. These expanded submerged experiments in a bioreactor were also carried out for mutant H4002. The results showed that (177.7-196.0) g/L citric acid was accumulated by H4002 through exploiting corn meal hydrolysate (containing initial 200.0-235.7 g/L sugar) with the productivity of (2.96-3.27) g/(L∙h). This was especially true when the initial sugar concentration was 210 g/L, and the best economical citric acid production reached (187.5±0.7) g/L with a productivity of 3.13 g/(L∙h). It was observed that mutant H4002 can utilize low-cost corn meal as a feedstock to efficiently produce citric acid. These results imply that the H4002 strain has the industrial production potentiality for citric acid and offers strong competition for the citric acid industry.
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China; Key laboratory of Microbial Resources Exploition and Application, Lanzhou 730000, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Hu
authors.forename: Jing
authors.initials: J
authors.lastname: Liu
authors.forename: Ji-hong
authors.initials: JH
authors.lastname: Chen
authors.forename: Shu-yang
authors.initials: SY
authors.lastname: Wang
authors.forename: Dong
authors.initials: D
authors.lastname: Lu
authors.forename: Qing-hua
authors.initials: QH
authors.lastname: Wu
authors.forename: Wen-jian
authors.initials: WJ
authors.lastname: Li
mesh_terms: D001234:Aspergillus niger / Q000235:genetics* / Q000378:metabolism* / Q000528:radiation effects; D019149:Bioreactors / Q000382:microbiology*; D050260:Carbohydrate Metabolism / Q000502:physiology; D019343:Citric Acid / Q000302:isolation & purification / Q000378:metabolism*; D024861:Genetic Enhancement / Q000379:methods*; D006868:Hydrolysis; D009154:Mutation / Q000235:genetics; D003313:Zea mays / Q000382:microbiology*
chemical_list: D019343:Citric Acid
keywords: Aspergillus niger; Citric acid; Corn meal hydrolysate; Mutation