• KSBB Journal
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• v.21 no.1 s.96
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• pp.54-58
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• 2006

The purpose of this study is to search the characteristics of PVA degrading enzymes which were obtained from Microbacterium barkeri KCCM 10507 and Paenibacillus amylolyticus KCCM 10508, respectively. As a result of the PVA degrading test using crude enzymes, the activity of SAO (secondary alcohol oxidase) was maximized after 2 or 3 days from start of the test, while the activity of BDH (${\beta}$-diketone hydrolase) was gradually increased during the test. Activities of them were maintained in the presence of PVA, but as PVA was gradually degraded, their activity was decreased. PVA was inoculated again into the media, their activity was revealed. This result indicated that above two different enzymes were closely connected with PVA degradation and PVA was degraded by activity of SAO and BDH. Maximum activity of them was 1.5-1.8 unit for SAO and 1.5-2.0 unit for BDH under $35^{\circ}C$ and pH 7.8-8.8, respectively.

• Journal of Microbiology and Biotechnology
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• v.22 no.2
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• pp.220-225
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• 2012

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.