• Journal of Microbiology and Biotechnology
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• v.11 no.6
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• pp.928-933
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• 2001

Approximately 0.1 mg/ml of polyvinyl alcohol (PVA) was degraded by the growing cell, Brevibacillus laterospours, for 30 h, and 0.2 mg/ml of PVA was degraded by the cell-free extract that was isolated from Brevibacillus laterosporus. Approximately $0.29{\mu}g$/ml of acetic acid was produced from PVA by using the cell-free extract as a catalyst for 40 min. $V_{max}\;and\;K_m$ value of purified PAV-degradation enzyme was 3.75g/l and 2.75 g/l/min in reaction with EDTA and 3.99 g/l and 2.98 g/l/min in reaction without EDTA, respectively. Molecular weight of the purified enzyme determined by SDS-PAGE was 63,000 Da. Alcohol dehydrogenase and aldehyde dehydrogenase activities were qualitatively detected on a native acrylamide gel by an active staining method, indicating the existence of the metabolic pathway to use PVA as a substrate.

• 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.

• The Korea Journal of Herbology
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• v.23 no.4
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• pp.9-19
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• 2008

Objectives: In this study the authors investigated effects of the ethanolic extract of Rhodjola Rosea(HKC) on fatigue and hypothalamic IEG expression in rat forced swimming(FS) model. Methods: Sprague-Dawley rats were administered HKC extract(25 mg/100g, p.o.) for 3 days prior to FS, some rats underwent 10 min FS and others exhaustive forced swimming(EFS). In addition, other rats were administered extract at different times after EFS over 3 consecutive days. Results: When HKC administered before 10 mins of FS, serum actate dehydrogenase(LDH) and creatine phosphokinase(CPK) activities were significantly lower than control group. When HKC administered prior to EFS, blood lactate was significantly lower versus control group. When HKC was administered after EFS, blood lactate(at 6 and 24 hours after EFS) were significantly lower and serum LDH, CPK activities(at 24 hours after EFS) were significantly lower versus control group. When HKC was administered after EFS, c-Fos positive neurons in hypothalamic periventricular area(PVA), medial part(mPVN) and anterior hypothalamic nucleus caudal part(AHC) were significantly lower at 24 hours after EFS than in control group. HSP-72 positive neuron numbers in hypothalamus were significantly lower at 24 hours after EFS than in control group. Finally, when HKC was administered prior to 10 mins FS, HIF-$1{\alpha}$ expression in the gastrocnemius muscle was significantly increased. Conclusions: These results suggest that HKC extract has an anti-fatigue effect, and it reduces neuronal cell stress responses induced by physical stress by having a beneficial effect on lactate metabolism.