• 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 Microbiology and Biotechnology
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• v.14 no.6
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• pp.1190-1195
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• 2004

In recent years, there has been an intensive research on decolorization of dye and textile wastewater by various fungal strains. In this study, the decolorization ability of three commercial dyes, acid yellow 99, acid blue 350, and acid red 114, were investigated using 10 fungal strains. Among the fungal strains tested, Trametes versicolor KCTC 16781 completely decolorized all dyes in both solid and liquid experiments, and was also able to decolorize the mixture of those three dyes in liquid experiments. The secretion of the ligninolytic enzymes into the extracellular medium during decolorization by T versicolor KCTC 16781 was also studied. No lignin peroxidase activity was detected, and manganese peroxidase and laccase activities were investigated.

• Microbiology and Biotechnology Letters
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• v.27 no.6
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• pp.477-483
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• 1999

For Trametes sp. CJ-105, a kind of white-rot fungi which was collected from the mountain of Korea and was proven to be effective in decolorizing a wide range of structurally different synthetic dyes, the optimum conditions for mycelial growth and laccase(E.C. 1.10.3.2) production were investigated. Among various carbon sources, glucose showed the highest potential for the mycelial growth and laccase production, the optimum concentration being 2% glucose. For the nitrogen source, asparagine was good for the mycelial growth, while ammonium tartrate for laccase production(optimum concentration: 0.04%). The addition of thiamine and biotin increased both th emycelial growth and laccase production. When 2,5-xylidine was added as an inducer after the first day of culture, the production of alccase was seven-times higher than that in the absence of the inducer. The optimum pH and temperature conditions for laccase production by Trametes sp. CJ-105 were pH 5.0 and $25^{\circ}C$, respectively. In the 5L fermentation, the production of laccase reached a maximum of 340U/ml at the time when the ammonium ion was being rapidly depleted.

• Journal of Mushroom
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• v.20 no.2
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• pp.86-91
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• 2022

Pleurotus eryngii, a white rot fungus, produces two extracellular lignin-degrading enzymes, laccase and manganese peroxidase (MnP). Owing to these enzymes, P. eryngii efficiently degrades synthetic chemicals such as azo, phthalocyanine, and triphenyl methane dyes. In this study, we investigated the degradation processes of four aromatic dyes, congo red (CR), methylene blue (MB), crystal violet (CV), and malachite green (MG), by P. eryngii under solid and liquid culture conditions. CR and MG were the most quickly degraded under solid and liquid culture conditions, respectively. However, compared to CR, CV, and MG, MB was not degraded well under both culture conditions. The activities of ligninolytic enzymes (laccase and MnP) were also investigated. Laccase was identified to be the major enzyme for dye degradation. A positive relationship between decolorization and enzyme activity was observed for CR, MB, and CV degradation. In contrast, decolorization of MG ensued after high enzyme activity. These results indicate that the degradation process differs between MG and the other aromatic dyes. Therefore, P. eryngii could be a potential tool for the bioremediation of synthetic aromatic dye effluent.

• Journal of the Korean Wood Science and Technology
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• v.24 no.4
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• pp.74-81
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• 1996

리그닌분해능(分解能)이 높은 균주(菌株)로 선발(選拔)된 Coriolus versicolor-13 (CV-13), LKY-7 및 LKY-12세 균주(菌株)에 대하여 균체외(菌體外) laccase 생산(生産)을 검토(檢討)하였다. Glucose-peptone broth에서 균체외(菌體外) laccase활성(活性)은 CV-13의 경우 3일 이상배양후(以上培養後)에 나타났고 LKY-7과 LKY-12균주(菌株)의 laccase 활성(活性)은 배양(培養) 2일째에 검출(檢出)되었다. 탄소원(炭素源)으로서는 maltose가 glucose와 비슷한 laccase 생산효과(生産效果)를 나타냈고 질소원(窒素源)으로서는 유기태질소(有機態窒素)가 무기태(無機態) 질소(窒素)보다 효과적(效果的)이었다. Laccase 유도물질(誘導物質)로서는 2,5-Xylidine이 가장 우수하였으며 1mM 이하(以下)의 농도(濃度)에서는 유도효과(誘導效果)가 크게 나타났으나 1.5mM 이상(以上)의 농도(濃度)에서는 laccase생산(生産)이 억제(抑制)되었고, 균사생장(菌絲生長) 초기(初期)에 첨가(添加)하는 것이 효과적(效果的)으로 나타났다. SDS-PAGE 후, CV-13 균주(菌株)의 균체외(菌體外) 단백질(蛋白質)에서는 약 69, 66, 25, 23, 19kDa 크기의 laccase band가 5개 나타났고 LKY-7 균주(菌株)에서는 27kDa과 19kDa 크기의 2개 band가, LKY-12 균주(菌株)에서는 22, 20, 17kDa 크기의 laccase band가 3개 나타났다.

• Journal of the Korean Wood Science and Technology
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• v.23 no.4
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• pp.27-32
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• 1995

To understand whether ligninolytic enzyme catalyze polymerization or depolymerization of the high molecular weight (HMW) lignin, the action of laccase and Mn-peroxidase (MnP) towards commercial ligninsulfonates (LS) was examined in various conditions of pH and cosubstrates. Polymerization occurred when LS was incubated with laccase at pH 6.0. In contrast, the high molecular weight portions were significant1y reduced at pH 4.5, especially when glucose was added. When LS was treated with MnP at pH 4.5, compounds of low molecular weight were produced. In particular, when cellobiose was added to Mn-P reaction mixture, the breakdown of LS was observed. In conclusion, degradation of LS by laccase and MnP occurred primarily at pH 4.5 where-as polymerization of LS was dominant at pH 6.0. Color index, however, was not greatly changed in the degradation mixtures of LS.

• Clean Technology
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• v.10 no.3
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• pp.131-137
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• 2004

Due to the low biodegradability of dyes, conventional biological wastewater treatment systems are inefficient in treating textile wastewater. In this study, white rot fungus, Trametes versicolor KCTC 16781, were investigated for the decolorization of Reactive black 5 solutions. This fungus was able to degrade the dye solutions by the ligninolytic enzymes (laccase and MnP) produced. The enzyme activity remained constant until the end of reaction. The combined process of biological treatment and ceramic membrane showed better efficiency for decolorization and TOC removal than each single process.

• Mycobiology
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• v.44 no.4
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• pp.260-268
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• 2016

Regulation of alkaline-resistant laccase from Perenniporia tephropora KU-Alk4 was proved to be controlled by several factors. One important factor was the initial pH, which drove the fungus to produce different kinds of ligninolytic enzymes. P. tephropora KU-Alk4 could grow at pH 4.5, 7.0, and 8.0. The fungus produced laccase and MnP at pH 7.0, but only laccase at pH 8.0. The specific activity of laccase in the pH 8.0 culture was higher than that in the pH 7.0 culture. At pH 8.0, glucose was the best carbon source for laccase production but growth was better with lactose. Low concentrations of glucose at 0.1% to 1.0% enhanced laccase production, while concentrations over 1% gave contradictory results. Veratryl alcohol induced the production of laccase. A trace concentration of copper ions was required for laccase production. Biomass increased with an increasing rate of aeration of shaking flasks from 100 to 140 rpm; however, shaking at over 120 rpm decreased laccase quantity. Highest amount of laccase produced by KU-Alk4, 360 U/mL, was at pH 8.0 with 1% glucose and 0.2 mM copper sulfate, unshaken for the first 3 days, followed by addition of 0.85 mM veratryl alcohol and shaking at 120 rpm. The crude enzyme was significantly stable in alkaline pH 8.0~10.0 for 24 hr. After treating the pulp mill effluent with the KU-Alk4 system for 3 days, pH decreased from 9.6 to 6.8, with reduction of color and chemical oxygen demand at 83.2% and 81%, respectively. Laccase was detectable during the biotreatment process.

• 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 Mushroom
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• v.10 no.2
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• pp.74-82
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• 2012

Sixty strains of Pleurotus ostreatus, white-rot fungi, were screened for production ability of their lignocellulolytic enzymes to selectively wood degradation. That results were shown that all of screened strains were produced lignocellulolytic enzymes on 2nd screening liquid culture medium. However, cellulase activity of selected six strains of P. ostreatus was low in avicel-yeast-peptone liquid culture medium. In the case of xylan degrading enzyme, No. 6 and No. 38 strains produced a xylanase(above 1.0U/ml) and a 1,4-${\beta}$-xylosidase (above 0.15 U/ml). Examination of the ligninolytic enzyme profiles of selected thirteen strains of the P. ostreatus, in the presence of Remazol Brilliant Blue R(RBBR), were observed that laccase(Lac) activity were earlier reached maximum level(0.8-2.0 U/ml) and then Mn-dependent peroxidase (MnP) were reached maximum level(0.5-1.5 U/ml) in glucose-yeast-peptone(GYP) medium. On the other hand, activity of lignin peroxidase(LiP) was not detected in this medium. I selected the No. 42 strain of P. ostreatus produced high levels of Mn-dependent peroxidase and laccase based on the screening method.