• Journal of Microbiology and Biotechnology
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• 제14권4호
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• pp.863-867
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• 2004

$\alpha$-Galactosidase from A. oryzae DR-5 was induced in the presence of melibiose, raffinose, galactose, and locust bean galactomannan. The enzyme was purified to homogeneity by precipitation with acetone followed by ion-exchange chromatography using DEAE-Sephacel. The purified enzyme showed a single band in both nondenaturing-PAGE and SDS-PAGE. The enzyme was a glycoprotein in nature by activity staining. The molecular weight of the purified enzyme was 93-95 kDa by SDS-PAGE. The enzyme exhibited the optimum pH and temperature at 4.7 and $60^\circ{C}$, respectively. $\alpha$-Galactosidase activity was strongly inhibited by $Ag^{2+}, Hg^{2+}, Cu^{2+}$, and galactose. EDTA, 1,10-phenanthraline, and PMSF did not inhibit the enzyme activity, whereas N-bromosuccinimide completely inhibited enzyme activity. Investigation by TLC showed complete hydrolysis of stachyose and raffinose in soymilk in 3 h at pH 5.0 and $50^\circ{C}$.

• Ecology and Resilient Infrastructure
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• 제7권2호
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• pp.134-144
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• 2020

In-situ stabilization is a remediation method using amendments to reduce contaminant availability in contaminated soil. We tested the effects of two amendments (furnace slag and red mud) on the availability of toxic trace elements (TTEs) and soil enzyme activities (dehydrogenase, phosphatase, and urease). The application of amendments significantly decreased the availability of TTEs in soil (p < 0.05). The decreased availability of TTE content in soils was accompanied by increased soil enzyme activities. We found significant negative relationships between the TTE content assessed using Ca(NO₃)_2^-, TCLP, and PBET extraction methods and soil enzyme activities (p < 0.01). Soil enzyme activities responded sensitively to changes in the soil environment (pH, EC, and availability of TTEs). It could be concluded that soil enzyme activities could be used as bioindicators or ecological indicators for soil quality and health in environmental soil monitoring owing to their high sensitivity to changes in soil.

• Journal of Applied Biological Chemistry
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• 제43권4호
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• pp.240-245
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• 2000

Two genes encoding maltooligosyltrehalose synthase (SaMTS) and maltooligosyltrehalose trehalohydrolase (SaMTH) were isolated from a hyperthermophilic microorganism, Sulfolobus acidocaldarius (ATCC 49462). ORFs of the SaMTS and SaMTH genes are 2,163 and 1,671 bp long and encode 720 and 556 amino acid residues, respectively. A bifunctional fusion enzyme (SaMTSH) was constructed through the gene fusion of SaMTS and SaMTH. Recombinant SaMTS, SaMTH, and SaMTSH fusion enzyme were overexpressed in E. coli BL21. SaMTS and SaMTH produced trehalose and maltotriose from maltopentaose in a sequential reaction. SaMTSH fusion enzyme catalyzed the sequential reaction in which the formation of maltotriosyltrehalose was followed by hydrolysis leading to the synthesis of trehalose and maltotriose. The SaMTSH fusion enzyme showed the highest activity at pH 5.0-5.5 and $70-75^{\circ}C$. SaMTS, SaMTH, and SaMTSH fusion enzyme were active in soluble starch, which resulted in the production of trehalose.

• 한국식품영양과학회지
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• 제27권4호
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• pp.596-602
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• 1998

Two kinds of sweet potato puree were prepared with Benihayato cultivar of yellow sweet potato with or without $\alpha$-amylase enzyme treatment. Chemical and rheological properties of enzyme-treated puree were different from those of control puree. Reducing sugar content and iodine value increased by $\alpha$-amylase enzyme treatment, while alcohol insoluble solids and viscosity decreased by enzyme treatment. However, the changes of carotenoid content were not significantly different. Hunter-b-values(yellowness) were 27.19 and 23.54 for no enzyme-treated puree(NTP) and enzyme-treated puree(ETP), respectively. Hunter-a values(redness) were 2.24 and 6.05 for NTP abd ETP, respectively. Content of total carotenoid of canned puree heated at 13$0^{\circ}C$ for 30 min decreased by 59 percents.

• 한국식품영양과학회지
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• 제6권1호
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• pp.27-33
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• 1977

The alkaline protease was isolated from the culture of Penicillium species (P-46) grown in the wheat bran media. The crude purification of this enzyme was carried out by extraction with distilled water and precipitated with 0.7-saturated ammonium sulfate, then dialysis for 3days. The activity of this enzyme was determined by Folin's colorimetric method. The results were as follows; 1. The optimum pH and temperature of this enzyme were pH 8.4 and $45^{\circ}C$. 2. This enzyme was stable at pH $7.0{\sim}9.0$. 3. This enzyme was not inactivated by treatment in lower temperature than $30^{\circ}C$. 4. The activity of this enzyme was strongly inhibited by $Hg^{++}$ and $Cu^{++}$, but slightly by $Ag^+$ 5. This enzyme was not inhibited by cystein, thiourea, ${\varepsilon}-aminocaproic$ acid, 2, 4-DNP, EDTA but strongly inhibited by PCMB.

• Journal of Ginseng Research
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• 제14권1호
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• pp.21-26
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• 1990

The chemical composition and stabilities of the purified ginseng invertase were investigated. The purified enzyme was found to be a glycoprotein composed of 80.2% protein and 19.7% total sugar. The protein component of the enzyme was composed of acidic amino acid (9.3%), basic amino acid (48.9%), nonpolar amino acid (21.4%), polar amino acid (20.4%) and 6.1% S-containing amino acid. It showed especially high contents of histidine and serine. The enzyme was inactivated almost completely by the treatment with some proteases (papain, pepsin. trypsin, pancreatin and microbial alkaline pretense) and protein denatllrants (8M urea and 6M guanidine-HC1), bolt not with glyrosidase (${\alpha}$-amylase, ${\beta}$-amylase. glcoamylese and cellullase). btonosaccharides sllch as glilrose, fructose, galactose and mannose did not exert any influence on the enzyme activity. The activity of the enzyme was inhibited by Ag+, Mn2+, Hg2+, Zn2+ and Al3+, whereas Ca2+, Mg2+, Ba2+ and Fe3+ gave rather activating effects on the enzyme activity. The enzyme was relatively stable in the VH range of VH 6 and 8, and at the temperatures below 35$^{\circ}C$.

• International Journal of Industrial Entomology and Biomaterials
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• 제27권2호
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• pp.322-325
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• 2013

In the present study, we report that the selection of operation mode is important to take the full advantage of nanofibrous membrane in enzyme immobilization. Silk fibroin nanofibrous membrane has been prepared by electrospinning, and a-chymotrypsin was immobilized as a model enzyme. When the immobilized enzyme was operated in the membrane reactor mode, the Michaelis constant, Km, was lower and the Vmax was higher compared to the batch reactor mode. No concentration gradient was observed in the membrane reactor mode and the immobilized enzyme was stable even after 7 times of re-use. Our results suggests that the enzyme immobilized nanofibrous membrane should be operated in the membrane reactor mode rather than in the bath reactor mode.

• 대한화장품학회지
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• 제26권1호
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• pp.81-92
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• 2000

Development of stabilized enzyme was attempted for cosmetic applications. Papain, a proteolytic enzyme, was stabilized through conjugation with a soluble carbohydrate biopolymer, SC-glucan$^{TM}$ . With a novel structure of the conjugation site, stability of the enzyme was significantly enhanced such that more than 90% of the initial activity retained after a month storage at 45$^{\circ}C$, while no activity were detected in native enzyme or enzyme simply mixed with SC-glucan$^{TM}$ after the storage. Conjugation with SC-glucan$^{TM}$ not only extended the half-life of the enzyme on storage at higher temperature, but was also found to protect enzymes against some components contained in cosmetic products for skin care. Cosmetic lotion containing 1 % papain conjugate was more effective and less irritative in exfoliating stratum corneum of human skin than the lotion containing 5% lactic acid, one of the current popular exfoliating agents.gents.

• Journal of Plant Biology
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• 제25권2호
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• pp.73-81
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• 1982

The changes in activities of glyoxysomal and peroxisomal enzymes during the transition from fat degradation to photosynthesis were investigated with the cotyledns of rape (Brassica napus L.) seedlings. The development and disappearance of glyoxysomal enzyme (isocitrate lyase, EC 4.1.3.1; malate dehydrogenase, EC 1.1.1.37; catalase, EC 1.11.1.6) activities took place independently of light. It is concluded that the mobilization of storage fat is independent of photomorphogenesis. During early periods of development in the dark of light (days 1 through 3), the glyoxysomal enzyme activities were relatively high and the enzyme activities rose to a peak at 3rd day after sowing. Thereafter, the activities decreased gradually. While glyoxysomal enzyme activities were dropping, the peroxisomal enzyme (glycolate oxidase, EC 1.1.3.1) activities were increasing rapidly during the transition period in the light. Moreover, the changes of enzyme activities of the common microbody marker, catalase, indicated both functional patterns. The enzyme patterns in rape cotyledons indicate that the glyoxysomal function of microbodies is replaced by the peroxisomal function of these organelles during the transition from fat degradation to photosynthesis.

• 한국양식학회지
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• 제16권4호
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• pp.233-239
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• 2003

부화 직후부터 변태를 완료하는 58일째까지 찰가자미 자어에서 소화효소들의 활성과 성장이 조사되었다. 자어들은 먹이를 공급하지 않는 조건과 충분히 공급하는 두 가지 조건에서 사육되었고 일정한 간격으로 성장과 함께 acid phosphatase(ACPase), alkaline phosphatase (ALPase)의 비활성 및 trypsin-like enzyme과 pepsin-like enzyme의 활성 변화를 파악하였다. 절식구에서 전장의 성장은 부화 후 7일까지 빠르게 증가하였으나, 이후부터는 거의 변화가 없었고 먹이 공급구의 경우 부화시 5.13$\pm$0.18mm였던 것이 58일 후 13.43$\pm$1.40mm로 성장하였다. 절식구의 개체 당 건조 체중은 부화 직후부터 기아로 사망이 발생한 12일째까지 시간이 경과할수록 감소하였다. 먹이 공급구의 경우 난황이 흡수될 때까지는 감소하였지만, 부화 후 20일째부터 빠르게 증가하기 시작하였다. ACPase와 ALPase 비활성은 절식구의 경우 실험을 종료할 때까지 증가하였으나, 먹이공급구는 부화 후 20일까지 증가한 후 실험을 마칠 때까지 서서히 감소하였으며 두 실험구 사이에서는 유의적인 차이가 없었다. 절식구의 trypsin-like enzyme 활성은 부화 후 3일부터 증가하여 6일째에 가장 높은 활성을 나타내었으나 난황을 완전히 흡수한 이후부터는 활성이 거의 검출되지 않았다. 먹이 공급구의 경우 부화 후 3일부터 난황을 완전히 흡수할 때까지 빠르게 증가하였고,20일째 가장 높은 활성을 나타내었다. Trypsin-like enzyme 활성은 부화 후 8일부터 먹이공급구가 절식구보다 유의적으로 높게 나타났다. Pepsin-like enzyme 활성은 두 실험구 모두에서 부화 초기에는 증가하였으나, 절식구에서는 실험종료 시까지 감소하였고, 먹이 공급구는 부화 후 10일째 높은 활성을 나타낸 후 일시적으로 감소하지만 부화 후 20일째 다시 높은 활성을 나타낸 후 실험 종료 시까지 서서히 감소하였다. Pepsin-like enzyme 활성은 8일째와 10일째 절식구가 먹이공급구보다 유의적으로 높게 나타났다. 이상의 결과들을 종합해보면 ACPase, ALPase의 비활성 및 trypsin-like enzyme과 pepsin-like enzyme치 활성은 자어의 성장이나 형태 발달과 깊은 연관이 있었다. 그리고 trypsin-like enzyme과 pepsin-like enzyme의 활성은 자어의 발달 단계, 성장 및 먹이 공급 등에 영향을 받기 때문에 자어의 건강이나 성장 상태를 나타낼 수 있는 간접적인 지표로써 이용 할 수 있겠다.