• 한국식품영양학회지
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• 제29권5호
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• pp.760-766
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• 2016

To increase the collagen recovery rate, bromelain (PB) and a microbial enzyme (PM) were used to treat to pork skin with single agent or combinations. The quality of collagen from the pork skin was evaluated by enzymatic treatments. The highest results for the solid contents and pork skin recovery rate obtained with the microbial-enzyme-bromelain mixtue (PMB) were 13.60% and 18.05% respectively. The result also showed that the color was affected by different types of enzyme treatments. Although PM treatment showed the highest result in the protein content of 251.30 mg/100 g, PMB treatment was the highest in the test of collagen content of 37.73 g/100 g among the treatments. However bands of the pork skin were detected widely at 130 kDa and 170 kDa ranges in SDS-PAGE. The band of PB treatment showed at the range of below 17 kDa, changed into a smaller molecular weight. The collagen content test of the pork skin by the treatments, collagen contents with combination treatment of pork skin with PMB (0.5%) resulted the highest in 43.76 g/100 g. Also the fat content at the above treatment was reduced to 11.12% compared to the other treatments. With these results of this experiment, we conclude that the enzymatic treatments were effective for the processing property of pork skin like enhancing the yield of collagen.

• Journal of Microbiology and Biotechnology
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• 제32권6호
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• pp.749-760
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• 2022

α-Galactosidase is a debranching enzyme widely used in the food, feed, paper, and pharmaceuticals industries and plays an important role in hemicellulose degradation. Here, T26, an aerobic bacterial strain with thermostable α-galactosidase activity, was isolated from laboratory-preserved lignocellulolytic microbial consortium TMC7, and identified as Parageobacillus thermoglucosidasius. The α-galactosidase, called T26GAL and derived from the T26 culture supernatant, exhibited a maximum enzyme activity of 0.4976 IU/ml when cultured at 60℃ and 180 rpm for 2 days. Bioinformatics analysis revealed that the α-galactosidase T26GAL belongs to the GH36 family. Subsequently, the pET-26 vector was used for the heterologous expression of the T26 α-galactosidase gene in Escherichia coli BL21 (DE3). The optimum pH for α-galactosidase T26GAL was determined to be 8.0, while the optimum temperature was 60℃. In addition, T26GAL demonstrated a remarkable thermostability with more than 93% enzyme activity, even at a high temperature of 90℃. Furthermore, Ca²⁺ and Mg²⁺ promoted the activity of T26GAL while Zn²⁺ and Cu²⁺ inhibited it. The substrate specificity studies revealed that T26GAL efficiently degraded raffinose, stachyose, and guar gum, but not locust bean gum. This study thus facilitated the discovery of an effective heat-resistant α-galactosidase with potent industrial application. Meanwhile, as part of our research on lignocellulose degradation by a microbial consortium, the present work provides an important basis for encouraging further investigation into this enzyme complex.

• Journal of Applied Biological Chemistry
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• 제55권1호
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• pp.47-53
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• 2012

친환경 농법이 대두되면서 식물 병원균에 대한 길항능과 식물생장 촉진능을 동시에 가지는 plant growth promoting rhizobacterium (PGRP)을 이용해 식물병을 방제하는 미생물 농법이 선호되고 있다. 본 연구에서는 토양비옥도 지표효소로 알려진 5종의 토양효소활성 측정을 이용해 plant growth promoting rhizobacterium 균주인 Bacillus subtilis AH18, Bacillus licheniformis K11, Pseudomonas fluorescens 2112를 조합한 복합미생물제제와 시판중인 미생물농약, 화학농약을 처리한 고추경작지에서 토양미생물상을 분석하고 고추의 생장 및 수확량을 측정하여 메타지노믹스를 이용한 토양미생물 다양성 연구의 기초자료로 사용하고자 하였다. 토양효소활성의 측정에서 복합미생물제제 처리구가 dehydrogenase 3.5584 ${\mu}g$ TPF $g^{-1}h^{-1}$, urease 15.8689 ${\mu}g$ $NH_4{^-}N$ $g^{-1}h^{-1}$, phosphatase 0.5692 ${\mu}g$ PNP $g^{-1}h^{-1}$, ${\beta}$-glucosidase 2.4785 ${\mu}g$ PNP $g^{-1}h^{-1}$, cellulase 86.1597 ${\mu}g$ glucose $g^{-1}h^{-1}$의 수치를 나타내 타처리구보다 높은 활성을 보여 토양미생물상의 다양성이 증대됨을 확인하였다. 또한, 고추의 생장촉진도측정에서 복합미생물제제가 타처리구에 비해 주경장에서 최대 6.1%, 경경에서 최대 8.1%의 생장촉진능을 보여 복합미생물제제의 생장촉진능을 확인하였다. 생고추의 수확량 측정에서는 복합미생물제제가 무처리구를 기준으로 했을 때 14%의 수확량 증대효과를 나타내었고, 화학농약 처리구보다도 7.3%의 증대효과를 나타내어 복합미생물제제에 의한 수확량 증대효과도 확인하였다. 따라서 본 연구에 사용된 복합 미생물컨소시움제제가 고추경작지 토양의 미생물상 다양성 증가와 고추의 생장촉진 및 수확량 향상 모두에 기여함을 알 수 있었다.

• Journal of Applied Biological Chemistry
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• 제58권3호
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• pp.209-218
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• 2015

Fructooligosaccharides have been mainly produced by microbial fructosyltransferases (FTase) enzymes. The present work focuses on the optimization of medium composition and cultivation parameters affecting FTase produced by Penicillium aurantiogriseum AUMC 5605 in shake flask cultivation. FTase production was optimized in two steps using DeMeo's fractional factorial design. A 1.46-fold increase in FTase production (105.4 U/mL) was achieved using the optimized culture medium consisting of (g/L): sucrose, 600; yeast extract, 10; $K_2HPO_4$, 5; $MgSO_4{\cdot}7H_2O$, 0.5; $(NH_4)_2SO_4$, 1.0 and KCl, 0.5. The obtained results showed that the maximum FTase enzyme activity was produced at initial cultivation pH values ranging from 6.0-6.5, at agitation speed of 200 rpm and using vegetative fungal cells as inoculum. Moreover, results showed that optimization of medium composition and some cultivation parameters resulted in an increase of about 93.7% in the enzyme activity than the nonoptimized cultivation conditions after 96 h of cultivation. Additionally, maximum production and specific production rates recorded 2340 U/L/h and 102 U/L/h/g cells, respectively.

• Journal of Ecology and Environment
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• 제33권3호
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• pp.223-228
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• 2010

Soil microbes perform crucial roles in the nutrient cycles of forest ecosystems, by effecting the decomposition of organic matter. Enzyme activities have been used to evaluate decomposition rates, as well as microbial activities. The principal objectives of this study were to determine the activities of different soil enzymes, to compare enzyme activities at different elevations, and to elucidate the most important controlling variables for enzyme activities. We conducted a field survey at three sites in Mt. Jumbong on a monthly basis from May, 2004 to September, 2005. Enzyme activities did not change substantially over different seasons. However, the spatial differences were distinct; the lowest elevation site evidenced the lowest levels of enzyme activity. Soils at the lowest elevation were nutrient-depleted soils, and enzyme activities appeared to be affected by precipitation and temperature. However, enzyme activities in fertile soils at high elevations were associated with nutrients and organic matter. The enzyme activities detected in this study differed significantly at the three elevations, and their controlling variables also evidenced different factors.

• KSBB Journal
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• 제17권4호
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• pp.381-387
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• 2002

본 연구의 목적은 기존의 단일 균주보다 두 종의 서로 다른 균주를 복합시켰을 때 두 균주간의 상호 보완적인 면을 이용하여 효소생산을 극대화하기 위함이며, 다음과 같은 결론을 얻었다. 실험에서 사용된 T viride와 FB01는 최적 PH와 온도가 비슷하여 혼합배양이 가능하였으며, 이들의 복합균주를 개발하는데 성공하였다. 즉 두 균주는 회분배양 하였을 때, 서로의성장속도에 차이가 있었기 때문에 두 균주의 생장균형을 유지하기 위해 접종시기를 조절할 필요가 있었다. 접종시기를 변화시킴으로서 두 균주간의 상호작용으로 인해 단일 균주일때보다 CMCase, $\beta$-glucosidase 및 avicelase의 활성이 우수했으며 또한 계대배양을 통한 두 균주의 활성유지에 관한 실험에서는 pH 조절을 통해 $\beta$-glucosidase 활성이 최고 3.2배까지증가함을 알 수 있었다. 따라서 배양액내에서 초기 pH의 영향은 생산된 cellulase complex의 다양한 구성요소의 상대적인 농도를 결정하는 실질적인 요인으로 판명된다. pH 4.5에서의 enzyme activity는 12.5 U/mL CMCase, 2.46 U/mL If-glucosidase, 0.93 U/mL avicelase였으며 개발당시의 복합균주활성인, 2.04 U/ml CMCase, 0.78U/ml $\beta$-glucosidase, 0.2 U/mL avicelase과 비교할 때 각각 6, 3.2, 4.7배의 높은 활성을 보였다. 복합균주의 탄소원으로 볏짚을 이용했을 때 복합균주에 의한 효소생산이 단일 균주인 T. virile나 FB01보다 훨씬 높게 나타났으며, 이때의 볏짚의 최적 농도는 5%(w/v)였다. 이러한 배양조건에서 복합균주를 장기적으로 계대배양하면서 효소의 생산성 향상과 복합균주의 안정성을 관찰할 필요가 있다고 사료된다.

• Journal of Microbiology and Biotechnology
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• 제14권1호
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• pp.56-61
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• 2004

A plasmid pSDK-l containing the Escherichia coli phosphofructokinase-l gene (pfkA) was constructed, and transferred into extremely acidophilic Acidithiobacillus thiooxidans Tt-7 by conjugation with the aid of plasmid RP4 at a frequency of $10^{-5}$ per recipient. This plasmid was stable in A. thiooxidans. The pfkA gene from E. coli could be expressed in this obligately autotrophic bacterium, but the enzyme activity (21.6 U/g protein) was lower than that in E. coli (K12: 85.9 Dig protein; DF1010 carrying plasmid pSDK-l: 96.6 U/g protein). In the presence of glucose, the Tt-7 transconjugants consumed glucose, leading to a better growth yield.

• Molecular & Cellular Toxicology
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• 제1권3호
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• pp.189-195
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• 2005

Industrial development has increase consumption of crude oil and environmental pollution. A large number of microbial lipolytic enzymes have been identified and characterized to date. To development for a new lipase with catalytic activity in degradation of crude oil as a microbial enzyme, Acinetobactor sp. B2 was isolated from soil samples that were contaminated with oil in Daejon area. Acinetobactor sp. B2 showed high resistance up to 10 mg/mL unit to heavy metals such as Ba, Li, Al, Cr, Pb and Mn. Optimal growth condition of Acinetobactor sp. B2 was confirmed $30^{\circ}C$. Lipase was purified from the supernatant by Acinetobactor sp. B2. Its molecular mass was determined to the 60 kDa and the optimal activity was shown at $40^{\circ}C$ and pH 10. The activation energies for the hydrolysis of p-nitrophenyl palmitate were determined to be 2.7 kcal/mol in the temperature range 4 to $37^{\circ}C$. The enzyme was unstable at temperatures higher than $60^{\circ}C$. The Michaelis constant $(K_{m})\;and\;V_{max}$ for p-nitrophenyl palmitate were $21.8{\mu}M\;and\;270.3{\mu}M\;min^{-1}mg\;of\;protein^{-1}$, respectively. The enzyme was strongly inhibited by $Cd{2+},\;Co^{2+},\;Fe^{2+},\;Hg^{2+},\;EDTA$, 2-Mercaptoethalol. From these results, we suggested that lipase purified from Acinetobactor sp. B2 should be able to be used as a new enzyme for degradation of crude oil, one of the environmental contaminants.

• 미생물과산업
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• 제12권2호
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• pp.36-39
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• 1986

• 한국환경생물학회:학술대회논문집
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• 한국환경생물학회 2004년도 학술대회
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• pp.105-105
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• 2004