• Korean Journal of Plant Tissue Culture
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• v.22 no.2
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• pp.71-76
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• 1995

The effects of light on the activities of several antioxidative enzymes, catalase (CAT), superoxide dismutase(SOD), ascorbate oxidase(AO), and peroxidase(POD) were examined in the hairy root cultures of Phytolacca esculenta van Houtte induced by Agrobacterium tumefaciens $A_4$T. Activities of CAT, SOD, and AO were significantly decreased with incresing light intensity (500-2,000 lx). The activity of AO under high light condition (2,000 lx)was decreased by 92% compared to the dark condition. The activities of glutathoine peroxidase (GPO), ascorbate peroxidase (APO) and general POD were increased under lower light intensify below 500 lx. The activity of GPO under 2,000 lx was decreased by 85% compared to the dark condition. The activities of antioxidative enzymes were more decreased in blue light (400-500nm). The activities of antioxidative enzymes in blue light intensity were increased in lower light intensity below 30 lx, but decreased 21-70% under 200 lx. The activity of AO was decreased by 70% under 200 lx with increasing blue light intensity. Our results suggest that the activities of antioxidative enzymes in hairy roots might be inhibited by endogenous oxidants generated under the high blue light conditions.

• Applied Biological Chemistry
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• v.38 no.5
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• pp.414-421
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• 1995

In order to establish informations important to the measurement of lipoxygenase (LOX) activity, providing conditions most favorable for its action and determining factors that inhibit activity, the influence of extraction buffer, substrate, pH, storage, temperature, NaCl, $CaCl_2$, other cations and antioxidants on LOX activity, and localization of LOX in cucumber tissues were carried out. The most favored substrate for LOX was linolenic acid followed by linoleic and arachidonic acids. LOX activity in both peel and mesocarp tissue extracts was maximum at pH 5.5 and relatively stable at $40^{\circ}C\;and\;50^{\circ}C$ temperature. The condition of 0.2 M NaCl with pH 5.0 was observed to provide optimum LOX stability. The enzyme activity was reduced by addition of cations, $Mn^{2+},\;Cu^{2+}\;or\; Al^{3+}$, except $Ca^{2+}$ which stimulated activity of LOX. Butylated hydroxy anisole (BHA) and propyl gallate decreased LOX activity with increasing concentration. Cucumber peel had higher activity than other tissues, locule or mesocarp, of cucumber.

• Microbiology and Biotechnology Letters
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• v.44 no.3
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• pp.376-382
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• 2016

The amylolytic enzyme activities of nuruks collected or produced in this study were examined. A maximum α-amylase activity of 24,747.1 ± 777.7 units/mg protein was obtained for a nuruk incubated at a relative humidity of 40% at 30℃. A nuruk matured at a relative humidity of 50% at 25℃ showed the highest glucoamylase acitivity. Among the 98 fungal strains isolated from the nuruk exhibiting the highest amylolytic enzyme activities, 26 strains of Aspergillus oryzae and 18 strains of Rhizopus oryzae were identified. Rhizopus oryzae MBF345 showed an α-amylase activity of 36,724.9 ± 10.2 units/mg protein and a glucoamylase activity of 4,911.8 ± 48.1 SP. These values were 1.7-fold and 1.4-fold greater, respectively, than those of the control strain. Strain MBF345 was deposited as KCTC46312 in the Korean Culture Type Collection.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.4
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• pp.760-763
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• 2001

Five commercial salt-fermented shrimps contained 29.8~48.3% of salt 3.5%~7.3% of total nitrogen and 0.3~0.7g/100g of amino-nitrogen respectively. The average peptide length(APL) of five commercial salt-fermented shrimps ranged from 10.1 to 15.0. Sample B and E showed longer APL than the others with the values of 15.0 and 14.4 respectively. Protease activity showed the large differences in five samples from 17 unit to 232 unit ; sample C showed the highest protease activity with 232 unit while sample D and E were relatively lower with 17 unit and 18 unit respectively. The chitinase activities which can hydrolyze chitin the one of components on outer layer of shrimp ranged from 14.4 unit to 171 unit. Sample E had the highest chitinase activity as 171 unit but sample B showed the lowest activity with 14.4 unit. Chitooligosaccharides of five commercial salted-fermented shrimps were consisted of monoglucosamine diglucosamine and triglucosamine.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.3
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• pp.448-452
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• 2000

실험동물에서 곰피로부터 분리한 phlorglucinol은 acetaminophen의 투여로 현저히 증가된 간조직에 있어서 지질과선화의 함량을 억제하였다. Acetaminophen 투여에 따른 간 cytochrome P-450, aminopyrine N-deme-thylase 및 aniline hydroxylase 활성변동은 관찰할 수 없었다. 곰피 성분 투여군은 glutathione S-transferase의 활성에서는 대조군의 수준에는 미치지 않으나 효소의 활성이 acetaminophen 단독 투여군보다 현저히 증가되었다. 그리고 간조직중 glutathione의 함량은 phlorglucionl을 전처리군에서 acetaminophen 단독 투여군보다 증가되었다. Glutathione reductase 활성에서는 acetaminophen 투여군은 대조군보다 활성이 감소되었으며, 성분으로 전처리한 군은 acetaminophen 단독 투여군보다 증가 되었다. 따라서 곰피에서 분리한 페놀성화합물인 phloroglucinol은 acetaminophen 투여로 증가되던 지질과 산화함량을 감소시키며, acetaminophen 대사효소활성에서는 glutathione S-transferase의 활성이 증가되어 acetaminophen 의 대사를 촉진시키는 것으로 추정된다.

• Korean Journal of Microbiology
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• v.24 no.2
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• pp.133-140
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• 1986

Extracts of CO-autotrophically grown cells of Acinetobacter sp. 1 were shown to use thionin, methylene blue, or 2,6-dichlorophenol-indophenol, but not NAD, NADP, FAD, or FMN, as electron acceptors for the oxidation of CO under strictly anaerobic conditions. The CO dehydrogenase (CO-DH) in the thes bacterium was found to be an inducible enzyme. The enzyme activity was determined by an assay based on the CO-dependent reduction of thionin. Maximal reaction rates were found at pH 7.5 and $60^{\circ}C$, and the Arrhenius plot revealed an activation energy of 6.1 kcal/mol(25.5kJ/mol). THe $K_m$ m/ for CO was $154{\mu}M$. Known metalchelating agents tested had no effects on the CO-DH activity. No divalent cations tested affect the enzyme activity significantly escept $Cu^{2+}$ which suppressed the activity completely. The enzyme was inhibited by glucose and succinate. The same extracts catalyzed oxidation of hydrogen gas and formate with thionin as electron acceptor. The CO-DH of Acinetobacter sp. 1 was to have no immunological relationship with that of Pseudomonas carboxydohydrogena.

• Korean Chemical Engineering Research
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• v.52 no.3
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• pp.302-306
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• 2014

The present study was carried out to optimize fermentation parameters for the production of cellulolytic enzymes through solid substrate fermentation of Trichoderma reesei and Aspergillus niger grown on wheat straw. A sequential optimization based on one-factor-at-a-time method was applied to optimize fermentation parameters including temperature, pH, moisture content and particle size. The results of optimization indicated that $40^{\circ}C$, pH 7, moisture content 75% and particle size between 0.25~0.5 mm were found to be the optimum condition at 96 hr fermentation. Under the optimal condition, co-culture of T. reesei and A. niger produced cellulase activities of 10.3 IU, endoglucanase activity of 100.3 IU, ${\beta}$-glucosidase activity of 22.9 IU and xylanase activity of 2261.7 IU/g dry material were obtained. Cellulolytic enzyme production with optimization showed about 72.6, 48.8, 55.2 and 51.9% increase compared to those obtained from control experiment, respectively.

• Microbiology and Biotechnology Letters
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• v.26 no.4
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• pp.345-351
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• 1998

In an effort to develop a potent system for the production of various dp (degree of polymerization) chitooligosaccharides, 32 enzymes or microbial systems were screened for chitosanolytic acitivity using chitosan as a substrate. The efficiency of each enzyme system was evaluated by the changes of turbidity and viscosity of chitosan solution, the amount of precipitate and the reducing sugar-producing activity in the enzymatic reaction mixture. Based on these assay methods for the chitosanase activity, Bacillus sp. P2l out of 32 screened systems showed highly potent endochitosanase, which was comparable with a commercially available enzyme (E7). Chitooligosaccharides of dp 3-7 were separated by TLC as major enzymatic reaction products, suggesting that the chitosanase from Bacillus sp. P2l be endo-splitting type.

• Applied Biological Chemistry
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• v.38 no.6
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• pp.502-506
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• 1995

A Bacillus strain which produces ${\beta}-galactosidase$ with high transgalactosylation activity, was isolated from soil and tentatively designated as Bacillus sp. A1. When ${\beta}-galactosidase$ from Bacillus sp. A1 reacted with 40% (w/w) lactose, transgalactosylation ratio reached up to 90% at the 70% conversion of the initial lactose. The biosynthesis of the enzyme in Bacillus sp. A1 required lactose as an inducer and was repressed by glucose. Observing that the addition of amino acids to culture medium resulted in enhancing, to a significant extent, both the growth and the enzyme production of the strain, yeast extract and commercially available hydrolysates of protein were examined for the suitability as amino acid source. As it turned out, SMP, an enzymatic hydrolysis product of soybean protein from Fuji Oil Co.(Japan), was the most suitable for optimization of the culture medium. When Bacillus sp. A1 was cultured in the presence of 0.5% SMP and 2% lactose, the enzyme activity increased up to $1.8\;U/m{\ell}-broth$.

• Journal of the Korean Wood Science and Technology
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• v.25 no.3
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• pp.29-36
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• 1997

목재부후균으로 부터 락케이스 효소의 생산 및 유도를 위하여 여러가지 유도약품(inducer)을 사용하였다. 이들 가운데 ferulic acid, pentachlorophenol 및 2,5-xylidine이 매우 높은 락케이스 활성을 나타나게 하였으며, 거의 동일한 유도효과를 보여주었다. 이들 약품 이외에도 sinapic acid, syringic acid 및 coffeic acid 등도 높은 락케이스 활성을 주었는데, 산의 형태가 알데히드류보다도 높은 유도효과를 나타냈다. 그리고 실험한 48개 균주 가운데 38개 균주가 락케이스를 생산하였으며, 이 가운데 32균주가 ferulic acid에 의해 강한 효소유도 활성을 보였다. 이러한 결과는 지금까지 락케이스 효소의 검출이 어려웠던 Abortiporus biennis 및 Gleophyllum odoratum에서도 높은 락케이스 효소의 유도를 가능하게 하였다. 아울러 가장 높은 효소활성을 나타낸 균주로서는 Cerrena unicolor 였으며, 그 락케이스 효소활성이 무처리 및 inducer 첨가시 각각 40,000 및 60,000 nkat/l 정도였다.