• KSBB Journal
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• v.21 no.2
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• pp.85-89
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• 2006

Typical property of the white-rot fungi is their ability to degrade lignin and other aromatic compounds with non-specific extracellular enzyme. In this work, the modification of the strain(Funalia trogii ATCC 200800) and the culture condition was performed to enhance enzyme productivity. Single cell was separated by the protoplasts formation and several putative laccase and manganese peroxidase inducers were tested. By adopting the modified strain, enzyme productivity increased comparing with that of the original strain. Extracellular enzyme formation was highly stimulated by the addition of copper and various aromatic compounds in the glucose-based culture medium.

• Journal of Microbiology
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• v.42 no.1
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• pp.37-41
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• 2004

The textile industry wastewater has been decolorized efficiently by the white rot fungus, Irpex lacteus, without adding any chemicals. The degree of the decolorization of the dye effluent by shaking or stationary cultures is 59 and 93%, respectively, on the 8th day. The higher level of manganese-dependent peroxidase (MnP) and non-specific peroxidase (NsP) was detected in stationary cultures than in the cultures shaken. Laccase activities were equivalent in both cultures and its level was not affected significantly by the culture duration. Neither lignin peroxidase (LiP) nor Remazol Brilliant Blue R oxidase (RBBR ox) was detected in both cultures. The absorbance of the dye effluent was significantly decreased by the stationary culture filtrate of 7 days in the absence of Mn (II) and veratryl alcohol. In the stationary culture filtrate, three or more additional peroxidase bands were detected by the zymogram analysis.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.163-163
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• 2005

• Proceedings of the Microbiological Society of Korea Conference
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• 2005.05a
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• pp.216.4-216
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• 2005

• Journal of Microbiology and Biotechnology
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• v.10 no.6
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• pp.737-752
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• 2000

Wood-rotting basidiomycetous fungi are the most efficient degraders of lignin on earth. The white-rot fungus Phanerochaete chrysosporium has been used as a model microorganism in the study of enzymology and its application. Because of the ability of the white-rot fungus to degrade lignin, which has an irregular structure and large molecular mass, this fungus has also been studied in relation to degrading and mineralizing many environmental pollutants. The fungus includes an array of enzymes, such as lignin peroxidase (LiP), manganese-dependent peroxidase (MnP), cellobiose:quinone oxidoreductase, and $H_2O_2$-producing enzymes and also produces many other components of the ligninolytic system, such as veratryl alcohol (VA) and oxalate. In addition, the fungus has mechanisms for the reduction of degradation intermediates. The ligninolytic systems have been proved to provide reductive reactions as well as oxidative reactions, both of which are essential for the degradation of lignin and organopollutants. Further study on the white-rot fungus may provide many tools to both utilize lignin, the most abundant aromatic polymer, and bioremediate many recalcitrant organopollutants.

• Journal of Photoscience
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• v.9 no.2
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• pp.430-432
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• 2002

The changes in expression of copper-zinc superoxide dismutase (CuZn-SOD), manganese superoxide dismutase (Mn-SOD) and glutathione peroxidase (GPX) in light-damaged rat retinas were examined. Sprague-Dawley rats (male, 6-weeks-old) were maintained on a cyclic photoperiod (12 hours light and 12 hours darkness) for 2 weeks. The illumination intensity during the light period was 80 lux. To induce light damage to the retina, a high-intensity illumination (3000-lux) was applied to the animals for 24 hours. After light exposure, the animals were returned to cyclic lighting. Eyes were enucleated 12 and 24 hours after light exposure started or 1,3, and 7 days after light exposure ended. Eyes were fixed and embedded in paraffin wax. Tissues were cut into 4${\mu}{\textrm}{m}$-thick sections. Sections were immunostained using antibody against CuZn-SOD, Mn-SOD, GPX and 8-hydroxy-deoxyguanocine (8-OHdG) as oxidative stress marker. 8-OHdG was observed in the outer nuclear layer (ONL) and retinal pigment epithelium (RPE) during light exposure. In light-damaged retinas CuZn-SOD labeling was up regulated in the ONL and RPE. Mn-SOD labeling was up regulated in rod inner segments (RIS) during light exposure and that in the RPE was up regulated after exposure. GPX labeling was observed in rod outer segments (ROS) during light exposure. GPX labeling was also observed in the RPE during and after light exposure. All three enzymes were observed in the outer retina, which suffered light damage, but occurred in defferent layers except within the RPE, in which case all three were expressed. These enzymes may play complementary roles as protective factors in light-damaged retinas.

• Journal of the Korean Wood Science and Technology
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• v.35 no.2
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• pp.85-95
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• 2007

Manganese dependent peroxidase (MnP) is the most ubiquitous enzyme produced by white-rot fungi, MnP is known to be involved in lignin degradation, biobleaching and oxidation of hazardous organopollutants. Bjerkandera fumosa is a nitrogen-unregulated white-rot fungus, which produces high amounts of MnP in the excess of N-nutrients due to increased biomass yield. The objective of this study was to optimize the MnP production in N-sufficient cultures by varying different physiological factors such as Mn concentration, culture pH, and incubation temperature. The growth of fungus was optimal in pH 4.5 at $30^{\circ}C$, $N_2$-unregulated white-rot fungus produces high amounts of MnP in the excess N-nutrients. The fungus produced the highest level of MnP (up to $1000U/{\ell}$) with $0.25g/{\ell}$ asparagine and $1g/{\ell}$ $NH_4Cl$ as N source at 1.5 mM $MnCl_2$ concentration, pH value of 4.5 at $30^{\circ}C$. Purification of MnP revealed the existence of two isoforms: MnPl and MnP2. The molecular masses of the purified MnPl and MnP2 were in the same range of 42~45 kDa. These isoforms of B. fumosa strictly require Mn to oxidize phenolic substrates. Concerned to kinetic constants of B. fumosa MnPs, B. fumosa has similar Km value and Vmax compared to the other white-rot fungi.

• Journal of Microbiology and Biotechnology
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• v.16 no.2
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• pp.226-231
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• 2006

Several white-rot fungi are able to produce extracellular lignin-degrading enzymes such as manganese peroxidase (MnP), lignin peroxidase (LiP), and laccase. In order to enhance the production of laccase and MnP using Trametes versicolor KCTC 16781 in suspension culture, the effects of major medium ingredients, such as carbon and nitrogen sources, on the production of the enzymes were investigated. The decolorization mechanism in terms of biodegradation and biosorption was also investigated. Among the carbon sources used, glucose showed the highest potential for the production of laccase and MnP. Ammonium tartrate was a good nitrogen source for the enzyme production. No significant difference in the laccase production was observed, when glucose concentration was varied between 5 g/l and 30 g/l. As the concentration of nitrogen source increased, a lower MnP activity was observed. The optimal C/N ratio was 25 for the production of laccase and MnP. When the concentrations of glucose and ammonium tartrate were simultaneously increased, the laccase and MnP activities increased dramatically. The maximum laccase and MnP activities were 33.7 U/ml at 72 h and 475 U/ml at 96 h, respectively, in the optimal condition. In this condition, over 90% decolorization efficiency was observed.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3173-3179
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• 2010

New complex $[Mn(II)H_{1.5}L]_2[Mn(II)H_3L]_2(ClO_4)_5{\cdot}3H_2O$ (1), where $H_3L$ is tris {2-(4-imidazolyl)methyliminoethyl} amine (imtren), has been prepared by reacting manganese(II) perchlorate hexahydrate with the imtren ligand in methanol. X-ray crystallographic study revealed that the imtren ligand hexadentately binds to Mn(II) ion through the three Schiff-base imine N atoms and three imidazole N atoms with a distorted octahedral geometry, and the apical tertiary amine N atom of the ligand pseudo-coordinates to Mn(II), forming overall a pseudo-seven coordination environment. The hydrogen-bonds between imidazole and imidazolate of $[Mn(II)H_{1.5}L]^{0.5+}$ complex ions are extended to build a 2D puckered network with trigonal voids. $[Mn(II)H_3L]^{2+}$ complex ions constitutes another extended 2D puckered layer without hydrogen bonds. Two layers are wedged each other to constitute overall stack of the crystal. Peroxidase activity of complex 1 was examined by observing the oxidation of 2,2'-azinobis(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS) with hydrogen peroxide in the presence of complex 1. Generation of $ABTS^{+{\cdot}}$ was observed by UV-vis and EPR spectroscopies, indicating that the complex 1, a fully-coordinated mononuclear Mn(II) complex with nitrogen-only ligand, has a heme-independent peroxidase activity.

• The Korean Journal of Mycology
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• v.26 no.1 s.84
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• pp.8-15
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• 1998

The present research was undertaken to investigate the activity of ligninolytic enzymes and the decolorization capability of some dyes with Irpex zonatus BN2, isolated from nature and identified. For the assay of enzyme activities, the isolate did not produce lignin peroxidase (LiP) and veratryl alcohol oxidase (VAO), but laccase and manganese dependent peroxidase (MnP). While the activity for MnP was low $(61.6\;nmol/mg{\cdot}protein)$, its laccase activity was very high $(1185.9\;nmol/mg{\cdot}protein)$. Moreover, laccase had appeared earlier than MnP. When the isolate was incubated with each dye for 10 days, the decolorization rates of azo dyes, such as orange II, orange G, tropaeolin O and congo red were 98.0%, 97.4%, 99.0% and 95.3%, respectively. In case of heterocyclic dyes, eosin Y, toludine blue, methyl blue and azur B were 97.4 %, 98.7%, 99.9% and 94.0% respectively. Finally the results of triphenylmethane dye such as basic fuchsin, malachite green and crystal violet were 98.5%, 95.7% and 99.4%, respectively. The results suggest that laccase of Irpex zonatus BN2 should be played an important role in the decolorization of the dyes.