• Forest Science and Technology
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• 제13권4호
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• pp.158-163
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• 2017

We examined the activities of lignin-degrading enzymes of the mycelium of cauliflower mushroom (Sparassis latifolia). Three different strains of S. latifolia collected from several sites in Korea and one crossbred strain were cultured on potato dextrose broth (PDB) and Kirk's medium in order to study the activities of their ligninolytic enzymes. Mycelial growth reached maximum levels between 14 and 21 days after inoculation and pH increased by 0.12 units over 35 days. Laccase activity began increasing after 14 days on both types of media. Manganese peroxidase (MnP) activity followed a trend similar to that of laccase on Kirk's medium, but not on PDB. The activity of lignin peroxidase (LiP) differed from that of other enzymes; its activity decreased by half after 14 days on PDB but remained constant on Kirk's medium over 35 days. The total protein concentration increased considerably after 14 days and peaked at 21 days on PDB. A similar maximum was attained on Kirk's medium. In contrast, the residual glucose increased rapidly at 14 days on Kirk's medium, while increasing gradually up to 28 days on PDB. This study indicates that S. latifolia is more similar to white rot fungi than to other brown rot fungi.

• Biotechnology and Bioprocess Engineering:BBE
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• 제8권2호
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• pp.130-134
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• 2003

A visual method for the selective screen Eng of lignin degrading enzymes, produced by white rot fungi (WRF), was investigated by the addition of coloring additives to solid media. Of the additives used in the enzyme production media, guaiacol and RBBR could be used for the detection of lignin peroxidase (LiP), manganese peroxidase (MnP) and lactase. Syringaldazine and Acid Red 264 were able for the detection of both the MnP and lactase, and the LiP and laccase, respectively, and a combination of these two additives was able to detect each of the ligninases produced by the WRF on solid media.

• Mycobiology
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• 제39권1호
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• pp.64-66
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• 2011

Most fungi possess several hydrogen peroxide-generating enzymes, glucose oxidase and pyranose oxidase. Pyranose oxidase can use glucose as its substrate to generate hydrogen peroxide. White rot fungi, which degrade diverse recalcitrant compounds, contain lignin-degrading enzymes, and lignin peroxidase and manganese peroxidase require hydrogen peroxide for their enzymatic reactions. In this study, we isolated a cDNA fragment of pyranose oxidase from Phlebia tremellosa using PCR and examined its expression under the degradation conditions of diethylphthalate (DEP). Pyranose oxidase expression was enhanced up to 30% by the addition of DEP, and this result supports the possible involvement of pyranose oxidase in the degradation of recalcitrant compounds.

• KSBB Journal
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• 제17권1호
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• pp.14-19
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• 2002

본 연구의 목적은 회전생물반응기에 고정화한 P. chrysosporium IFO 31249를 이용하여 LiP 생산의 최적 조건을 조사하는 것이다. 회전생물반응기에서 batch culture시 최대 LiP 활성도는 300 U/L이었다. LiP 생산의 최적 조건은 드림의 회전 속도는 1 rpm, 담체 충진율은 20%이었다. MnP 생산을 위한 $MnSO_4$$\cdot$$H_2O$ 의 최적 농도는 50 ppm이었다. 그리고 산소의 충분한 공급은 LiP 생산의 가장 중요한 인자이었다. 또한 LiP 및 MnP의 생산에 있어 repeated-batch culture가 3번이나 가능하였다.

• 미생물학회지
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• 제44권3호
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• pp.199-202
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• 2008

리그닌을 분해하는 백색부후균의 하나인 기계충버섯(Irpex lacteus)은 다양한 난분해성물질에 대한 분해능이 매우 높다. 그러나 이 균은 다양한 배양조건에서도 리그닌 분해효소의 하나인 laccase 활성이 매우 낮다. 난분해성 물질들에 대한 분해능을 향상시키기 위하여 laccase 활성을 증가시키고자 아교버섯의 laccase cDNA를 발현벡터로 구축하여 기계충버섯에 형질전환 방법으로 도입하였다. 항시 발현되는 glyceraldehyde-3-phosphate dehydrogenase 유전자의 프로모터와 재조합된 laccase 유전자는 생성된 형질전환체에서 배양초기인 생장기에서 강하게 발현되었으며, 생성된 형질전환체가 내분비장애물질의 하나인 비스페놀 A (BPA) 분해능은 물론 에스트로겐 활성 제거에 있어서도 더 우수하였다.

• Journal of Microbiology and Biotechnology
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• 제22권2호
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• pp.239-243
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• 2012

Degradation of butylbenzyl phthalate (BBP) by the white rot fungus Pleurotus ostreatus and the activities of some degrading enzymes were examined in two different media containing 100 mg/l of the compound. P. ostreatus pre-grown for 7 days in complex YMG medium was able to completely degrade BBP within an additional 24 h but degraded only 35 mg/l of BBP in 5 days of incubation in minimal medium. Fungal cell mass in the culture in YMG medium was higher in the presence than in the absence of BBP. The esterase activity of the fungal culture in YMG medium was higher than that in minimal medium and increased with the addition of BBP. On the contrary, laccase activity was higher in minimal medium and it did not increase upon the addition of BBP. General peroxidase activity increased for a few days after the addition of BBP to both media. The degradation of BBP and its metabolites by P. ostreatus thus may be attributed mostly to esterase rather than lignin-degrading laccase. In addition, the activities of the enzymes involved in BBP degradation and their changes varied significantly in the different media and culture conditions.

• Journal of Microbiology
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• 제45권3호
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• pp.213-218
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• 2007

Trametes versicolor has a lignin degrading enzyme system, which is also involved in the degradation of diverse recalcitrant compounds. Manganese-dependent peroxidase (MnP) is one of the lignin degrading enzymes in T. versicolor. In this study, a cDNA clone of a putative MnP-coding gene was cloned and transferred into an expression vector (pBARGPE1) carrying a phosphinothricin resistance gene (bar) as a selectable marker to yield the expression vector, pBARTvMnP2. Transformants were generated through genetic transformation using pBARTvMnP2. The genomic integration of the MnP clone was confirmed by PCR with bar-specific primers. One transformant showed higher enzyme activity than the recipient strain did, and was genetically stable even after 10 consecutive transfers on non-selective medium.

• Journal of Animal Science and Technology
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• 제57권7호
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• pp.23.1-23.6
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• 2015

Cellulose degrading bacteria from koala faeces were isolated using caboxymethylcellulose-Congo red agar, screened in vitro for different hydrolytic enzyme activities and phylogenetically characterized using molecular tools. Bacillus sp. and Pseudomonas sp. were the most prominent bacteria from koala faeces. The isolates demonstrated good xylanase, amylase, lipase, protease, tannase and lignin peroxidase activities apart from endoglucanase activity. Furthermore many isolates grew in the presence of phenanthrene, indicating their probable application for bioremediation. Potential isolates can be exploited further for industrial enzyme production or in bioremediation of contaminated sites.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2011년도 춘계학술발표회 논문집
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• pp.81-91
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• 2011

Current fuel ethanol research and development deals with process engineering trends for improving biotechnological production of ethanol. Recently, a large amount of studies regarding the utilization of lignocellulosic biomass as a good feedstock for producing fuel ethanol is being carried out worldwide. The plant biomass is mainly composed of cellulose, hemicellulose and lignin. The main challenge in the conversion of biomass into ethanol is the complex, rigid and harsh structures which require efficient process and cost effective to break down. The isolation of microorganisms is one of the means for obtaining enzymes with properties suitable for industrial applications. For these reasons, crude cultures containing cellulosic biomass degrading microorganisms were isolated from rice field soil, cow farm soil and rotten rice straw from cow farm. Carboxymethyl cellulose (CMC), xylan and Avicel (microcrystalline cellulose) degradation zone of clearance on agar platefrom rice field soil resulted approximately at 25 mm, 24 mm and 22 mm respectively. As for cow farm soil, CMC, xylan and Avicel degradation clearancezone on agar plate resulted around at 24mm, 23mm and 21 mm respectively. Rotten rice straw from cow farm also resulted for CMC, xylan and Avicel degradation zone almost at 24 mm, 23 mm and 22 mm respectively. The objective of this study is to isolatebiomass degrading microbial strains having good efficiency in cellulose hydrolysis and observed the effects of different substrates (CMC, xylan and Avicel) on the production of cellulase enzymes (endo-glucanase, exo-glucanase, cellobiase, xylanase and avicelase) for producing low cost biofuel from cellulosic materials.

• 미생물학회지
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• 제46권1호
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• pp.93-95
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• 2010

리그닌 분해효소 군을 가진 백색부후균들은 다핵방향족 화합물을 포함하여 염료와 폭약 및 내분비장애 물질의 분해 등 다양한 난분해성 물질을 분해할 수 있다. 리그닌 분해효소 중 laccase와 manganese peroxidase (MnP)를 각각 발현하는 벡터를 국내에서 분리한 백색부후균류의 하나인 아교버섯(Phlebia tremellosa)에 형질전환 방법으로 도입시킨 형질전환체를 사용하여 염료의 탈색능력을 분석하였다. Methyl green의 경우 3일 후 약 50%의 탈색을 보인 야생형에 비하여 laccase 형질전환체(TF2-1)와 MnP 형질전환체(T5) 모두 90% 이상의 탈색을 보였다. Remazol brilliant blue R (RBBR)에서는 야생형이 약 67%의 탈색을 보인 반면 두 가지 형질전환체들은 약 85%의 탈색을 보였다. 각각의 형질전환체들은 laccase와 MnP의 활성 및 유전자 발현도 활발한 것으로 확인되었다.