• Journal of Microbiology and Biotechnology
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• 제16권2호
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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.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권2호
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• pp.96-99
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• 2006

In this study, we have attempted to determine the optimum concentration of inducers responsible for efficient laccase production by the white-rot fungus, Trametes sp. Variations in laccase activity were investigated with changing concentrations of 2,5-xylidine, syringaldazine, ABTS, and guaiacol. Enhancement of peak laccase activity was achieved via the combination of 2,5-xylidine with ABTS, syringaldazine, or guaiacol, resulting in increases of up to 359, 313, and 340%, respectively, as compared to control values. Among the tested inducers, the addition of 0.1mM of ABTS coupled with 1.0mM of 2,5-xylidine in the medium after 24 h of cultivation proved optimal with regard to laccase enzyme production.

• 한국미생물·생명공학회지
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• 제42권3호
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• pp.225-231
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• 2014

마늘낙엽버섯(Marasmius scorodonius)에 대하여 리그닌 분해 여부를 조사한 결과, 본 균주는 laccase를 생산하는 백색부후균으로 확인되었다. 마늘낙엽버섯 균사체로부터 laccase를 생산하기 위한 최적배지조건을 조사한 결과, 다양한 합성 배지 중에서 YM (1% dextrose, 0.5% malt extract, 0.3% yeast extract) 배지가 가장 높은 laccase 활성을 나타내었다. 또한 YM 배지의 조성 중에서 탄소원과 질소원을 각각 1% galactose와 0.4% yeast extract로 대체하였을 때 가장 높은 효소활성을 나타내었다. 본 균주는 최적배지조건에서 $25^{\circ}C$로 15일 동안 배양하였을 때 효소의 활성이 최대치에 도달함을 확인하였다. 균사체 배양 상등액을 Native-PAGE로 전기영동한 후 활성염색을 수행한 결과, 분자량 약 60-70 kDa 사이에서 laccase 활성을 가지는 2개의 밴드를 확인하였으며, 효소의 최적 pH와 온도는 각각 pH 3.4과 $75^{\circ}C$이었다.

• Journal of Microbiology and Biotechnology
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• 제26권9호
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• pp.1570-1578
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• 2016

Commercial application of laccase is often hampered by insufficient enzyme stocks, with very low yields obtained from natural sources. This study aimed to improve laccase production by mutation of a Coriolopsis gallica strain and to determine the biological properties of the mutant. The high-yield laccase strain C. gallica TCK was treated with N-methyl-N-nitro-N-nitrosoguanidine and ultraviolet light. Among the mutants isolated, T906 was found to be a high-production strain of laccases. The mutant strain T906 was stabilized via dozens of passages, and the selected ones were further processed for optimization of metallic ion, inducers, and nutritional requirements, which resulted in the optimized liquid fermentation medium MF9. The incubation temperature and pH were optimized to be 30℃ and 4.5, respectively. The mutant strain T906 showed 3-times higher laccase activity than the original strain TCK under optimized conditions, and the maximum laccase production (303 U/ml) was accomplished after 13 days. The extracellular laccase isoenzyme 1 was purified and characterized from the two strains, respectively, and their cDNA sequence was determined. Of note, the laccase isoenzyme 1 transcription levels were overtly increased in T906 mycelia compared with values obtained for strain TCK. These findings provide a basis for C. gallica modification for the production of high laccase amounts.

• 한국균학회지
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• 제31권3호
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• pp.181-186
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• 2003

담자균류 80여종에서 laccase 고생산 균주(Fomitella fraxinea; 장수버섯)를 선발하고, F. fraxinea를 이용한 리그닌 분해효소의 생산 및 효소의 대량생산 조건을 검토하였다. 먼저 배지 조성에 따른 생산성을 조사한 결과 Cu등의 무기물의 첨가 유무에 따라 생산되는 효소가 달랐다. 무기물이 첨가되지 않은 배지(Medium I)에서는 manganese peroxidase가 생산되었고, 무기물이 첨가된 배지(Medium II)에서는 laccase가 생산되었는데 플라스크 배양 18일째에는 5.43 U/ml, 20일째에는 5.56 U/ml의 효소활성이 나타났다. 배양방법에서 영양이 충분한 조건에서는 정치배양보다는 진탕배양(120 rpm)에서 효소의 활성이 높았다. 이 균주를 이용한 laccase 대량생산 실험에는 jar fermentor, balloon type bioreactor, air-sparging fermentor를 이용하였다. laccase는 jar fermentor와 air-sparging formentor에서 3,540 U/ml(8일), 3,100 U/ml(6일)의 생산성을 나타내었다. Balloon type bioreactor는 균사의 생장은 좋았지만 효소는 생산되지 않았다. F. fraxinea를 사용하여 air-sparging fermentor로 scale up하여 laccase의 대량생산을 할 수 있다고 판단된다.

• Journal of Microbiology
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• 제43권3호
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• pp.301-307
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• 2005

The feasibility of laccase production by immobilization of Pleurotus ostreatus 1804 on polyurethane foam (PUF) cubes with respect to media composition was studied in both batch and reactor systems. Enhanced laccase yield was evidenced due to immobilization. A relatively high maximum laccase activity of 312.6 U was observed with immobilized mycelia in shake flasks compared to the maximum laccase activity of free mycelia (272.2 U). It is evident from this study that the culture conditions studied, i.e. biomass level, pH, substrate concentration, yeast extract concentration, $Cu^{2+}$ concentration, and alcohol nature, showed significant influence on the laccase yield. Gel electrophoretic analysis showed the molecular weight of the laccase produced by immobilized P. ostreatus to be 66 kDa. The laccase yield was significantly higher and more rapid in the packed bed reactor than in the shake flask experiments. A maximum laccase yield of 392.9 U was observed within 144 h of the fermentation period with complete glucose depletion.

• 한국미생물·생명공학회지
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• 제45권4호
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• pp.330-342
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• 2017

Statistical design of experiments was employed to optimize the media composition for the production of laccase from Bacillus sp. PK4. In order to find the key ingredients for the best yield of enzyme production from the selected eleven variables viz yeast extract, glucose, zinc sulphate, copper sulphate, potassium chloride, magnesium sulphate, calcium chloride, ferrous sulphate, sodium chloride, potassium dihydrogen phosphate ($KH_2PO_4$) and dipotassium hydrogen phosphate ($K_2HPO_4$), Plackett-Burman design was applied. The $MgSO_4$, $FeSO_4$, and $CuSO_4$ showed positive estimate, and their concentration optimized further. The steepest ascent method and Box-Behnken method revealed that 1.5 mM $MgSO_4$, 0.33 g/l $FeSO_4$ and 1.41 mM $CuSO_4$ were optimal for the laccase production by Bacillus sp. PK4. This optimization strategy leads to enhancement of laccase production from 2.13 U/ml to 40.79 U/ml. Agro-wastes residues replace the carbon source glucose in the optimized media namely sugarcane bagasse, wheat bran, rice husk, and groundnut shell, among these groundnut shells (117 U/ml) was found to enhance the laccase production significantly. The laccase produced by Bacillus sp. PK4 was found to have the potential to degrade persistent organic pollutant benzo[a]pyrene.

• 한국미생물·생명공학회지
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• 제37권1호
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• pp.62-68
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• 2009

소나무잔나비버섯(Fomitopsis pinicola) 균사로부터 laccase를 생산하기 위한 최적 배양조건을 조사하였다. 합성 배지 중 MCM이 가장 높은 laccase활성을 나타내었으며, MCM의 조성을 2% dextrose, 0.4% peptone, 0.05% $NaH_2PO_4{\cdot}H_2O$, 0.05% $CaCl_2$로 각각 대체하였을 때 효소활성이 가장 우수하였다. 따라서 F. pinicola로부터 laccase를 생산하기 위한 최적 배지조건은 2% dextrose, 0.4% peptone, 0.05% $NaH_2PO_4{\cdot}H_2O$, 0.05% $CaCl_2$이다. 이상의 배지를 사용하여 $25^{\circ}C$에서 8일 동안 배양하였을 때 효소의 활성이 최대에 도달함을 확인하였다. ABTS를 기질로 사용한 activity staining을 통해 소나무잔나비버섯 균사체의 laccase 활성의 분자량이 43-55 kDa임을 확인하였으며, 배양액 중의 최적 pH와 온도는 각각 pH 3.0과 $80^{\circ}C$이었다.

• 한국균학회지
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• 제13권2호
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• pp.111-114
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• 1985

The production of lac case by the funguson various media was studied. The characteristics of the enzyme were also studied regarding to the optimum pH, stability, Km value, and inactivation. The maximum activity of laccase reached the 40 days of incubation and the barley straw extract appeared to be a strong inducer for laccase. The enzyme showed stability at wide range of pH with optimum pH of 6.6. Temperature stability of the enzyme was high. Laccase was not inactivated by the organic solvents used for the precipitation. The enzyme, how­ever, was completely inactivated by trichloroacetic acid and sodium azide.

• Journal of the Korean Wood Science and Technology
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• 제24권4호
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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.