• Korean Journal of Microbiology
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• v.46 no.1
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• pp.93-95
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• 2010

White rot fungi which have lignin degrading enzymes show high degrading activity to diverse recalcitrant compounds such as polycyclic aromatic compounds, dyes, explosives and endocrine disrupting chemicals. We have examined decolorizing activity of dyes by Phlebia tremellosa and two transformants which had genetically transformed using laccase or manganese peroxidase (MnP) gene. In case of methyl green, wild type strain showed 50% decolorization while laccase transformant (TF2-1) and MnP transformant (T5) showed more than 90% decolorization on day 3. Remazol brilliant blue R(RBBR) was decolorized up to 85% by two transformants while the wild type showed 67% decolorization on day 3. Transformants TF2-1 and T5 both showed increased laccase and MnP activity respectively during the whole growing phase.

• Journal of Mushroom
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• v.17 no.4
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• pp.185-190
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• 2019

Pleurotus ostreatus No.42, known as the ligninolytic basidiomycetes, showed production of MnP and Lac, but did not show any LiP acitivity in static culture, grown in GPYW liquid medium. Maximum production of MnP (80U/flask) was observed on day 11 of culturing in this medium. Chromatographic purification of MnP included the use of Sepharose CL-6B and Mono-Q. The major MnP isozyme purified by column chromatography was observed to be a 36.4 KDa (single band on SDS PAGE). The 19-amino acid sequence from the N-terminal was determined by protein sequencing to be ATCADGRTTANAACCVLFP. The N-terminal sequence of the major MnP isozyme of P. ostreatus No.42 was found to be the same as a previously reported sequence of an MnP3 isozyme from this fungus.

• The Korean Journal of Mycology
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• v.31 no.3
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• pp.181-186
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• 2003

The production of laccase by Fomitella fraxinea was studied. The addition of minerals were necessary far laccase production by Fomitella fraxinea. Jar fermentor and Air-sparging fermentor performed high productivity In laccase activity by F. fraxinea. Laccase activity reached 3,540 in 8 days (Jar fermentor) and 3,100 in 6 days (Air-sparging fermentor) respectively.

• Journal of Mushroom
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• v.16 no.4
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• pp.272-278
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• 2018

Lignin degrading enzymes from Lentinula edodes have broad substrate specificities, and therefore can degrade a variety of recalcitrant compounds. In this study, the lignolytic biodegradation was investigated in five different L. edodes fungi (Chunbaegko, Sanjo 303ho, Poongnyunko, Baekhwahyang, and Soohyangko). The fungi were evaluated for their ability to decolorize Remazol Brilliant Blue R (RBBR) in malt extract broth medium. Sanjo 303ho, Poongnyunko, Baekhwahyang, and Soohyangko rapidly decolorized RBBR within 7 days. The activities of manganese peroxidase (MnP) and laccase were determined in the absence and presence of lignin. Poongnyunko displayed the highest ligninolytic activity on day 7 of incubation (2,809 U/mg and 2,230 U/mg for MnP and laccase, respectively).

• Journal of Mushroom
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• v.20 no.1
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• pp.29-33
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• 2022

In this study, five different Lentinula edodes cultivar (Chamaram, Sanbaekhyang, Sanjo 713ho, Sanjo 715ho, Sanjo 718ho) were evaluated for their ability to decolorize Remazol Brilliant Blue R (RBBR) in MEB medium, respectively. Chamaram and Sanjo 713ho decolorized RBBR rapidly in MEB medium within 3 and 5 days. The activities of manganese peroxidase (MnP) and laccase were determined on the MEB medium with and without lignin. Sanjo 713ho resulted the highest ligninolytic enzyme activities on incubation day 1, indicating of 1,213 U/mg of MnP activity and 1,421 U/mg of laccase activity.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.29 no.2
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• pp.83-90
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• 1997

An unbleached hardwood kraft pulp was bleached in vitro with partially purified manganese peroxidase (MnP) from the fungus Phanerochaete sordida YK-624 without the addition of MnSO$_4$ in the presence of oxalate, malonate or gluconate known as manganese chelator, When the pulp was treated without the addition of MnSO$_4$, the pulp brightness increased by about 10 points in the presence of 2 mM oxalate, but the brightness did not significantly increase in the presence of 50 mM malonate. Residual MnP activity decreased faster during the bleaching with MnP without MnSO$_4$ in the presence of malonate than in the presence of oxalate. Oxalate reduced MnO$_2$ which already existed in the pulp or was produced from $Mn^{2+}$ by oxidation with MnP and thus supplied $Mn^{2+}$ to the MnP system. Thus, bleaching of hardwood kraft pulp with MnP, using manganese originally existing in the pulp, became possible in the presence of oxalate, a good manganese chelator and reducing reagent. Properties of partially purified MnPs from liquid cultures of white rot fungi, Ganoderma sp. YK-505, Phanerochaete sordida YK-624 and Phanerochaete chrysosporium were compared. MnP from Ganoderma sp. YK-505 was superior to MnPs from P. sordida YK-624 and P. chrysosporium in stabilities against high temperature and high concentration of $H_2O$$_2$. The MnP from Ganoderma sp. YK-505 differed in pH-activity profile from other MnPs. These data suggest that MnP from Ganoderma sp. YK-505 has different structure from those of other fungi. Bleaching of hardwood kraft pulp using the MnP from ganoderma sp. YK-505 is now in progress.

• 한국균학회소식:학술대회논문집
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• 2014.05a
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• pp.43-43
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• 2014

White rot fungi have been useful source of enzymes for the degradation of environmental pollutants including polycyclic aromatic hydrocarbons (PAHs) and synthetic dyes. PAHs are widespread organic compounds present in fossil fuels and are routinely generated by incomplete fuel combustion. PAHs are some of the major toxic pollutants of water and soil environments. Synthetic dyes are major water-pollutants, which are toxic to organisms in water environments and interfere photosynthesis of water plants. Removal of PAHs and synthetic dyes has been of interests in the environmental science especially in the environmental microbiology. Mushrooms are fungal groups that function as primary degraders of wood polyphenolic lignin. The ligninolytic enzymes produced by mushroom, including manganese peroxidase, lignin peroxidase, and laccase, mediate the oxidative degradation of lignin. The catalytic power of these enzymes in the degradation of aromatic ring compounds has been sought for the degradation of various organic compounds. In this project, we have screened 60 wild mushroom strains for their degradation activity against two representative PAHs, naphthalene and anthracene, and five aromatic dyes, including alizarin red S, crystal violet, malachite green, methylene blue, rose bengal. The degradation of PAHs was measured by GC while the decolorization of dyes was measured by both UV spectrophotometer and HPLC. As results, 9 wild mushroom strains showed high activity in degradation of PAHs and textile dyes. We also describe the secretive enzyme activities, the transcription levels, and cloning of target genes. In conjunction with this, activities of degradative enzymes, including laccase, lignin peroxidase, and Mn peroxidase, were measured in the liquid medium in the presence of PAHs and dyes. Our results showed that the laccase activity was directed correlated with the degradation, indicating that the main enzyme acts on PAHs and dyes is the laccase. The laccase activity was further simulated by the addition of $Cu^{2+}$ ion. Detailed studies of the enzyme system should be sought for future applications.

• Journal of Ginseng Research
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• v.41 no.3
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• pp.307-315
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• 2017

Background: Red-skin root disease has seriously decreased the quality and production of Panax ginseng (ginseng). Methods: To explore the disease's origin, comparative analysis was performed in different parts of the plant, particularly the epidermis, cortex, and/or fibrous roots of 5-yr-old healthy and diseased red-skin ginseng. The inorganic element composition, phenolic compound concentration, reactive oxidation system, antioxidant concentrations such as ascorbate and glutathione, activities of enzymes related to phenolic metabolism and oxidation, and antioxidative system particularly the ascorbate-glutathione cycle were examined using conventional methods. Results: Aluminum (Al), iron (Fe), magnesium, and phosphorus were increased, whereas manganese was unchanged and calcium was decreased in the epidermis and fibrous root of red-skin ginseng, which also contained higher levels of phenolic compounds, higher activities of the phenolic compound-synthesizing enzyme phenylalanine ammonia-lyase and the phenolic compound oxidation-related enzymes guaiacol peroxidase and polyphenoloxidase. As the substrate of guaiacol peroxidase, higher levels of $H_2O_2$ and correspondingly higher activities of superoxide dismutase and catalase were found in red-skin ginseng. Increased levels of ascorbate and glutathione; increased activities of $\text\tiny L$-galactose 1-dehydrogenase, ascorbate peroxidase, ascorbic acid oxidase, and glutathione reductase; and lower activities of dehydroascorbate reductase, monodehydroascorbate reductase, and glutathione peroxidase were found in red-skin ginseng. Glutathione-S-transferase activity remained constant. Conclusion: Hence, higher element accumulation, particularly Al and Fe, activated multiple enzymes related to accumulation of phenolic compounds and their oxidation. This might contribute to red-skin symptoms in ginseng. It is proposed that antioxidant and antioxidative enzymes, especially those involved in ascorbate-glutathione cycles, are activated to protect against phenolic compound oxidation.

• Journal of Microbiology and Biotechnology
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• v.10 no.3
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• pp.344-348
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• 2000

Abstract The removal percentage (94%) of 100 ppm of pyrene in a shaken culture of white rot fungus, Irpex lacteus, was much higher than that in a static culture (37.9%). Over 90% of the pyrene disappeared with I. lacteus grown at $15-27^{\circ}C$, yet less than 50% was removed at $37^{\circ}C$. The transformation rates of pyrene ($4.5-5.0{\;}\mu\textrm{g}/ml/day$) were not very different among cultures with 5- 30% inoculum sizes, and over 90% of the 100 ppm pyrene was removed in every case during 20 days of incubation. The biodegradation of pyrene by I. lacteus was confirmed by measuring the $CO_2$ evolved from the mineralization of the added pyrene. The activity of lignin peroxidase (LiP), which is known to be involved in the biodegradation by white rot fungi, was high between 8 to 12 days of incubation. Although manganese peroxidase activity was demonstrated during the same period as LiP, its activity was quite low, and no laccase activity was detected. Even though the activity patterns of ligninolytic enzymes did not coincide with the pyrene removal, this study shows that I. lacteus has a high biodegrading capability and can be a candidate for the bioremediation of polycyclic aromatic hydrocarbon contaminants.inants.

• Journal of Microbiology and Biotechnology
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• v.17 no.7
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• pp.1147-1151
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• 2007

Biodegradation of endocrine-disrupting bisphenol A was investigated with several white rot fungi (Irpex lacteus, Trametes versicolor, Ganoderma lucidum, Polyporellus brumalis, Pleurotus eryngii, Schizophyllum commune) isolated in Korea and two transformants of T. versicolor (strains MrP 1 and MrP 13). I. lacteus degraded 99.4% of 50 mg/l bisphenol A in 3 h incubation and 100% in 12 h incubation. which was the highest degradation rate among the fungal strains tested. T. versicolor degraded 98.2% of 50 mg/l bisphenol A in 12 h incubation. Unexpectedly, the transformant of the Mn-repressed peroxidase gene of T. versicolor, strain MrP 1, degraded 76.5% of 50 mg/l bisphenol A in 12 h incubation, which was a lower degradation rate than wild-type T. versicolor. The removal of bisphenol A by I. lacteus occurred mainly by biodegradation rather than adsorption. Optimum carbon sources for biodegradation of bisphenol A by I. lacteus were glucose and starch, and optimum nitrogen sources were yeast extract and tryptone in a minimal salts medium; however, bisphenol A degradation was higher in nutrient-rich YMG medium than that in a minimal salts medium. The initial degradation of endocrine disruptors was accompanied by the activities of manganese peroxidase and laccase in the culture of I. lacteus.