• Applied Science and Convergence Technology
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• v.26 no.6
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• pp.157-163
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• 2017

Immobilized enzymes have become the subject of considerable interest due to their excellent functional properties such as reusability, cost-effectiveness, and optimality during the past decades. Enzyme immobilization technology is not only used in industrial processes, but also a component technology of products for medical diagnostics, therapy, food industry, bio energy, and biomaterial detection. In this review, new methods for enzyme immobilization are introduced, and the advantages and disadvantages of a variety of techniques in enzyme immobilization will be also discussed.

• YAKHAK HOEJI
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• v.38 no.1
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• pp.12-19
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• 1994

Capsaicin(8-methyl-N-vanillyl-6-nonenamide) is the principal pungent component of Capsicum fruits. This work is directed to the capsaicin-hydrolyzing enzyme playing a key role in the rate limiting and critical step of capsaicin metabolism. In order to get precise information on the enzyme's subcellular location, rat liver homogenate was divided into six subcellular fractions by differential centrifugation technique: crude nuclear pellet, PNS(post nuclear supernatant) fraction, lysosomal pellet, cytosol, Tris wash fraction, micrisomes. Capsaicin-hydrolysing enzyme activity was analysed by high performance liquid chromatography(HPLC). This enzyme was found at the highest specific activity in the microsomal fraction and co-distributed with marker enzymes of the endoplasmic reticulum, NADPH-cytochrome c reductase and nucleoside diphosphatase. This is compatible with the result of ninhydrin color reaction of vanillylamine, primary metabolite of capsaicin hydrolysis, on thin layer chromatography(TLC). This enzyme is most active at pH $8.0{\sim}9.0$. Definite subcellular location of this enzyme will make it easy to proceed with further study.

• Microbiology and Biotechnology Letters
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• v.23 no.1
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• pp.24-30
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• 1995

The effects of amino acids in growth media on the biosynthesis of Serratia marcescens biodegradative threonine dehydratase activity were examined. The enzyme activity was decreased by 44 and 34% by 10 mM isoleucine and valine, respectively, whereas it was increased approximately by 20% by 10 mM threonine. Among several metabolites tested, pyruvate increased the enzyme activity by 60% at 5 mM, but decreased the enzyme activity approximately by 20 to 70% above 20 mM. The enzyme activity was increased by 64% by 5 mM glyoxylate, whereas it decreased the enzyme activity approximately by 40 to 70% above 20 mM glyoxylate. The thiamine, monopyrrole derivative, also increased the enzyme activity by 84% at 50 $\mu $g/ml, but did not affected the enzyme activity above 300 $\mu $g/ml. cAMP increased the enzyme activity by 58% at 0.5 mM, but decreased the enzyme activity by 15% at 2 mM. These data suggested that the biosynthesis of Serratia marcescens biodegradative threonine dehydratase is regulated by concentrations of pyruvate, glyoxylate and cAMP.

• Korean Journal of Organic Agriculture
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• v.5 no.2
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• pp.141-152
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• 1997

This experiment was conducted to know the effects of foliar applicated bio-enzyme on the early growth of cucumber and red pepper seedlings. Bio-enzyme was manufactured by the culture and proliferation of Bacillus genus and foliar applicated by the concentration of 0.075, 0.15, 0.3 g.$\ell$-1. Foliar application of bio-enzyme had great influenced to the early growth both cucumber and red pepper seedlings. Optimum concentrations of bio-enzyme applicated for the growth of plant height were determined as of 0.075 g.$\ell$-1 in cucumber but in red pepper seedlings 0.15g.$\ell$-1 was more favored. However, foliar application of 0.15g.$\ell$-1 of bio-enzyme was recommended for both cucumber and red pepper seedlings. Especially, leaf area and total dry weight which are main indices of good seedling were highest in the plot of standard concentrations(0.15g.$\ell$-1)of bio-enzyme.

• Journal of the Korean Wood Science and Technology
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• v.27 no.4
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• pp.65-71
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• 1999

This study was carried out to investigate the effect of xylanase pretreatment of the unbleached hardwood kraft pulp during the conventional Chlorine-Extraction- Hypochlorite (CEH) bleaching on pulp property. Optimum bleaching condition was evaluated by using Novozym produced from the fungus Humicola insolens. Also the effect of chelating agent prior to enzyme treatment was analyzed. The kappa number of enzymatic bleached pulp at the enzyme charge 10 IU/ml was slightly similar to that of bleached pulp without enzyme. By enzyme treatment, the chlorine charge in conventional CEH bleaching process of hardwood KP could be reduced by 17%, while no adverse effect on pulp yield and strength was. The optimum condition for enzyme pretreatment was 10 IU/ml xylanase charge, 3 to 4 hrs treatment, and 2% pulp consistency. In sugar composition in the enzyme pretreated pulp, arabinose and mannose were not much different, but more xylose was retained. This high content of hemicellulose in pulp seems to play an important role in pulp properties. The pulp pretreatment by chelating agent prior to enzyme treatment could improve the enzyme activity and enhance the bleaching effect at 0.2% diethylenetriamine pentaacetic acid (DTPA) charges.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.3
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• pp.534-539
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• 1997

In order to reuse enzyme efficiently, a mthod for ionic binding of fructosyltransferase to a porous carrier bearing quaternary alkyl alkanolammonium groups was investigated. The fructosyltransferase activity of the immobilized enzyme increased with increasing amount of loaded enzyme, and maximally reached 770U/g of the carrier when loaded amount of the enzyme was 18.2 mg/g carrier. The immobilized fructosyltransferase had optimum pH and temperature of 7.5 and 45$^{\circ}C$, respectively, whereas soluble enzyme had 6.5 and 55$^{\circ}C$: the Km value for the immobilized enzyme was 27.8 mM for sucrose, which was the same as that of soluble enzyme. In a batch reactor, the enzyme produced a mixture of fructooligosaccharides, mainly F$_2$G, from sucrose with the slight loss of enzyme activity during continuous operation of 12 days at 42$^{\circ}C$.

• The Korean Journal of Food And Nutrition
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• v.12 no.3
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• pp.265-270
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• 1999

The stabilization of Aspergillus sp. $\alpha$-amylase was attained by modification with periodate-oxidized sol-uble starch. The pH stability of modified enzyme was increased at pH 3~4 and 9~11 in the presence of $\alpha$-cyclodextrin($\alpha$-CD) compared with that of native enzyme. Thermal stability of the modified enzyme was increased. After treatment at 6$0^{\circ}C$ for 30min the activity remained 20% for the enzyme modified at pH 9.7 in the presence of $\alpha$-CD and tested in the presence of $\alpha$-CD 10% for the enzyme modified at pH 9.7 in the presence of $\alpha$-CD 0% for the native enzyme. The native enzyme and modified enzyme showed one peak in HPLC. The substrate specificity of the modified enzyme was not changed in HPLC analysis of reaction product.

• Journal of Pharmaceutical Investigation
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• v.19 no.2
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• pp.81-86
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• 1989

The proteolytic enzyme extracted from Neungee [Sarcodon aspratus (Berk.) S. Ito] was purified by using Tris-acryl CM-cellulose column chromatography and chromatofocusing. The specific activity of the purified enzyme increased 15.8 times as compared with that of the crude enzyme. The enzyme was homogeneous on polyacrylamide gel electrophoresis and stable at pH values ranging from 4.0 to 10.8. The enzyme activity remained unchanged when the mushroom and the purified enzyme were stored for 3 years and 6 months at 4°C, respectively. The enzyme was found to be an endogeneous protease.

• Journal of Microbiology and Biotechnology
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• v.3 no.2
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• pp.99-107
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• 1993

Two strains (No. 26 and 143) of bacteria which secrete both pectinase and raw-starch-digesting amylase simultaneously, were isolated from various domestic soil samples. The two bacteria were identified as Pasteurella ureae judging by their morphological and physiological characteristics. The optimal culture conditions for the production of raw-starch-digesting enzyme by the Pasteurella ureae 26 were using $NH_4NO_3$ as the nitrogen source at $37^{\circ}C$ with the pH of 7.5, and 15 of C/N ratio. Since the enzyme was produced only when raw or soluble starch was used as a carbon source, but not when glucose or other sugars was used, the enzyme was considered to be an inducible enzyme by starch. Thin layer chromatography of the hydrolyzed product of starch by the raw-starch-digesting enzyme of the strain No. 26 showed that glucose, maltose and other oligosaccharides were present in the hydrolyzates, and therefore the enzyme seemed to be ${\alpha}-amylase$. The enzyme had adsorbability onto raw com starch in the pH range of 3 to 9.

• Microbiology and Biotechnology Letters
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• v.28 no.1
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• pp.52-58
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• 2000

The effect of fivrinolytic enzyme produced from Bacillus subtilis K-54 on the thrombosis and stress in vivo was investigated. Each partially purified fibrinolytic enzyme of 4 protein casein unit was administered orally for 3 days before intravenously injection with collagen and epinephrine. In the mice group administered with the enzyme and increased life span of mice was observed in comparison with that of control. The result suggest that the enzyme may prevent the formation of thrombos in vivo. Administration of the enzyme did not influence to stress itself because 5-hydroxyindoleacetatic acid concentration of brain in the mice group with stress did not decreased after the administration of the enzyme. The value of lipid peroxide (LPO) of the liver and brain cells in the group treted with the enzyme was lower than that of control. However, protein degradation (PDP value showed no significant difference between treatment and control groups. In addition, the value of activated partial thromboplastin time (APTT), protrombin time (PT0 and antiplasmin in blood were higher in the stress group than that of the enzyme treated group.