title: Enhancement of PVA-degrading enzyme production by the application of pH control strategy.
abstract: In batch culture for Poly(vinyl alcohol) (PVA)-degrading enzyme (PVAase) production by a mixed culture, higher pH (pH 7.5) was favorable for PVAase production at the prophase of cultivation, but lower pH (pH 7.0) was favorable at the anaphase. This situation was caused by the fact that the optimum pH for different key enzymes [PVA dehydrogenase (PVADH) and oxidized PVA hydrolase (OPH)] production is various. The activity and average specific production rate of PVADH reached the highest values at constant pH 7.5, whereas those of OPH appeared at pH 7.0. A two-stage pH control strategy was therefore developed and compared for its potential in improving PVAase production. By using this strategy, the maximal PVAase activity reached 2.05 U/ml, which increased by 15.2% and 24.2% over the fermentation at constant pH 7.5 and 7.0.
authors.affiliation: The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China.
authors.forename: Min
authors.initials: M
authors.lastname: Li
authors.forename: Dongxu
authors.initials: D
authors.lastname: Zhang
authors.forename: Guocheng
authors.initials: G
authors.lastname: Du
authors.forename: Jian
authors.initials: J
authors.lastname: Chen
mesh_terms: D001419:Bacteria / Q000254:growth & development* / Q000378:metabolism*; D003470:Culture Media / Q000737:chemistry*; D004798:Enzymes / Q000378:metabolism*; D005285:Fermentation; D006863:Hydrogen-Ion Concentration; D011142:Polyvinyl Alcohol / Q000378:metabolism*
chemical_list: D003470:Culture Media; D004798:Enzymes; D011142:Polyvinyl Alcohol