• Journal of the Korean Professional Engineers Association
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• v.17 no.1
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• pp.27-35
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• 1984

When starch is hydrolyzed either by acid or by the enzymes maltase or diastase, contained in germinating barley, a yield of 80% of maltose is obtained. Maltose is built of two molecules of ${\alpha}$-glucose, bound in the position 1:4 i.e., carbon atom 1 of one glucose molecule is bound in a glucosidic bond to carbon atom 4 of the second molecule. Until around 1960, dextrose and glucose syrups were prepared from starch exclusively by acid hydrolysis. The process was corrosive, and the dextrose yield low. It was, therefore, a great step forward when pure glucoamylase in combination with bacterial ${\alpha}$-amylase made possible a complete enzymatic hydrolysis of starch to dextrose. Today several enzymatic processes are used in the industry.

• Journal of Embryo Transfer
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• v.26 no.4
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• pp.223-227
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• 2011

The objective of this study was to compare of different isolation method of mouse preantral follicles, and to examine in vitro development of mouse preantral follicles isolated by different method. Preantral follicles were mechanically or enzymatically extracted from mouse ovaries. Mechanical isolation method used fine gauge needles and enzymatic method of isolating follicles used collagenase. The recovered preantral follicles were cultured for 10 days in alpha-minimal essential medium (${\alpha}$-MEM) + 5% FBS + Insulin-Transferrin-Selenium (ITS) + 100 mIU/ml FSH. The collected primary follicles by enzymatic treatment were higher than mechanical method. Others stage preantral follicle by mechanical isolation were higher than enzymatic method. After 10 days of culture, no statistical differences were shown in survival rates of preantral follicle among the 2 culture groups. The metaphase II rates of the oocytes were significantly higher (p<0.05) in mechanical method (17.8%) than in enzymatic method (5.1%). These results suggest that the isolation method of choice depends on the target stage preantral follicles and mechanical isolation is an optimal method of preantral folliclesin a culture of mouse preantral follicle.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.1
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• pp.115-123
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• 2001

This paper discussed the assessment of hand of cotton fabrics by enzymatic hydrolysis. The subjective hand and preference of denim fabrics finished by enzymatic hydrolysis were evaluated using the scale developed. The factors affecting consumers taste for denim fabrics were analyzed by the statistical technique. The effects of enzymatic hydrolysis on the properties of cotton fabrics were also evaluated by subjective hand measurements. The results are as follow; As the weight loss increased, evaluators thought that fabrics become finer, smoother, softer, warmer and more refined, and the sense of durability is sleeker and weaker, and the sense of weight is more flexible, flossier, lighter, softer, thinner. They didnt catch the change of moisture related properties according to the rate of weight loss. They also thought fabrics became more elastic, and less wrinklier as the weight loss increased. As the weight loss increased, the fabric was more preferred. The limited weight loss which changes the preference from \"dislike\" to \"like\" was 12.87%. The most preferred fabric was that with 12.87% of weight loss. It is supposed that the preference of fabric was related to the terms such as \"sum-se-ha-da\"(섬세하다), \"mai-ku-rup-da\"(매끄럽다), \"yoo-yon-ha-da\"(유연하다), \"too-bak-ji-an-da\"(투박하지 않다), \"chom-chom-ha-da\"(촘촘하다), \"gil-ki-da\"(질기다), \"kun-juk-goe-ri-ji-an-da\"(끈적거리지 않다), \"ku-kim-i-ka-ji-an-nun-da\"(구김이 가지 않는다).

• Journal of Microbiology and Biotechnology
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• v.2 no.3
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• pp.197-203
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• 1992

Studies of the pretreatment of chitin and its subsequent hydrolysis by Aspergillus carneus chitinase are reported. Ball milling was found to be the most effective way among the pretreatment methods tested. Data are presented describing the effect of enzyme and substrate concentrations on the rate and extent of the hydrolysis process. It was found that the successive addition of enzyme improved the saccharification yield. Significant product inhibition of the chitinase was observed when N-acetylglucosamine concentration was 3.6％ or higher. Adsorption of enzymes to the substrate occurred during a 24 hr hydrolysis period. An initial rapid and extensive adsorption occurred, followed by gradual desorption which increased during the time of reaction. Intermediate removal of the hydrolyzate and continuation of the hydrolysis by adsorbed enzyme on the residual chitin was also investigated. A total of 75.4 g/l reducing sugars, corresponding to 69.2％ saccharificaton yield (as N-acetylglucosamine) was obtained. In addition an increase in the amount of recoverable enzymes was observed under these conditions. Evidence presented here suggests that the technique, whereby the free enzymes in the recovered hydrolyzate are re-adsorbed onto the new substrate, may provide a means of recirculating the dissolved enzymes.

• Journal of Microbiology and Biotechnology
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• v.15 no.3
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• pp.537-543
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• 2005

Subtilisin (EC 3.4.21.14) is the major extracellular alkaline serine protease of Bacillus species. Previously, we found that subtilisins did not migrate in the electrophoretic field in the Laemmili buffer system due to their high pI values (over 8.8); however, it formed a 'binding mode' at the top of the separating gel [5]. Utilizing this characteristic, four subtilisins from Bacillus sp. strains (e.g., B. subtilis 168, B. subtilis KCTC 1021, B. amyloliquefaciens KCTC 3002, and Bacillus sp. DJ-1 and DJ-4) were easily and quickly identified by an over-running electrophoretic technique with a miniscale culture supernatant (less than 20 ml) without any column chromatographic steps. Two subtilisins (DJ-l and a recombinant version) from Bacillus sp. DJ-l were characterized, and the enzymatic properties were determined by SDS-fibrin zymography and densitometric analysis. Based on this observation, the recombinant pro-subtilisin DJ-l showed the same 'binding mode,' similar to native subtilisin DJ-l. On the other hand, mature subtilisin DJ -1 without pro-peptide showed no enzymatic activity.

• Archives of Pharmacal Research
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• v.16 no.4
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• pp.271-275
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• 1993

In order to prepare a novel human insulin analogue suhbstituted with homoserine at B$^{30}$ / position, (B$^{30}$ /-homoserine) human insulin, a synthetic gene was designed by linking directly a gene for B chain with that for A chain. This gene was constructed by enzymatic joining of 10 different synthetic oligonucleotides, and then inserted at the polylinker region of pUC19 plasmid. To achieve a high level of gene expression, the gene fusion technique region of pUC19 plasmid. To achieve a high level of gene expression, the gene fusion technique was employed using amino terminal regions of lacZ gene up to Clal or hpal, and either of them has been located under tac promoter. The chemical induction of these fused genes by isopropyl-.betha.-D-thiogalactopyranoside (IPTG) gave a satisfactory level of expression in Escherichia coli harboring the ocnstructed plasmids. It was observed that the fused gene product as a single chain insulin precusor was produced more than 30% of total cell protein of E. coli as a form of inclusion body.

• Food Science of Animal Resources
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• v.24 no.4
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• pp.411-415
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• 2004

The transparisation technology for milk and milk products could be applied widely and very importantly to various determination because transparisation can economize the cost and increase with precision in the milk payment system. Component of butanone or Triton in transparisation solvent would inhibit the growth of bacteria and method. Enzymatic determination of leucocytes were proposed to evaluate milk quality as mastitis in the milk payment system, this can be easily applied to simplify automation of the determation with the lowest investment cost in milk pay system. The significance of this technique, it can be used in the quality control of raw milk and milk products, milk payment system, and programming of national dairy project. Transparisation technology is used in somatic cell counting by enzymic methods. The range of deviation for this method is 16％ in 74 samples. But the deviation is increased to 20％ when the Infoss method is used. It is affected by the percentage of epithelial cells and white blood cells in somatic cells from different animals and the stages of aging. NAgase activity has an obvious correlation with white-blood cells in milk. In the case of mastitis the white-blood cells is 90-95％ in somatic cells in milk, it is showing greater precision in measuring the state of mastitis. In conclusion the enzymic method of somatic cell counting is a relatively simple and easy method of measurement and can be easily practiced. And the importance of this method is also worth utilizing for indirect counting of Somatic cells by use of synthetic substrates to NAgase. In the future, with the further development of the research in this field, it will b possible to automatize the measurement.

• Korean Journal of Microbiology
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• v.24 no.2
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• pp.79-85
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• 1986

We have determined the sequence of $tRNA^{Arg}$ of A. nidulans partially by enzymatic rapid RNA sequencing technique. The sequence was 5'GGCCGGCUGGCCCAAXUGGCAAGGXUCUGAXUACGAAXCAGGAGAUUGCACXXXXXGAGCXXUXXGUCGGUCACCA3' The cloverleaf structure was made from above data. As a result, the anticodon sequence was identified as ACG. This result was confirmed with charging test. The complete sequence was proposed by supplementing the DNA sequence to and by assigning the position of minor bases to this RNA sequence.

• BMB Reports
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• v.33 no.1
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• pp.43-48
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• 2000

4-Aminobutyrate aminotransferase is a key enzyme of the 4-aminobutyric acid shunt. It converts the neurotransmitter 4-aminobutyric acid to succinic semialdehyde. In order to study the structural and functional aspects of catalytically active Cys residues of pig brain 4-aminobutyrate aminotransferase, we purified the active form in E. coli by coproduction of thioredoxin. The structural arrangement for functional requirements of a dimeric protein using a bifunctional sultbydryl reagent was then characterized, and the spatial proximity between the essential SH groups and a cofactor (pyridoxal-5'-phosphate) binding site was determined. The bifunctional sultbydryl reagent DMDS reacted with the enzyme at the ratio of one molecule per enzyme dimer. This resulted in an approximately 50% loss of enzymatic activity. The spatial proximity of the distance between the essential SH groups and the cofactor-binding site was determined by the energy transfer measurement technique. The result (approximate 20 ${\AA}$) suggested that cross-linking of two sulfhydryl groups with DMDS is not near a PLP binding site.

• Journal of Chest Surgery
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• v.21 no.2
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• pp.231-239
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• 1988

Currently numerous methods are in use for myocardial hypothermia as a myocardial preservation modality for cardiac operation. During cardiac ischemia after crystalloid cardioplegia[4C GIK solution], topical cold saline[Group I, a=9], topical ice slush[Group II, n=9] and topical ice chip[Group III, a=10] have been compared for myocardial surface cooling in the isolated rat heart model of cardiopulmonary bypass. During postischemic period, hemodynamic functions[aortic flow, coronary flow, peak aortic pressure and heart rate], biochemical enzymatic activities and cellular injuries with electron microscope were evaluated in this isolated rat heart perfusion model. Postischemic aortic flow, cardiac output and peak aortic pressure in Group I and Group II recovered better than Group III.[p< 0.05] Postischemic creatine kinase and lactate dehydrogenase leakages in Group II and Group III increased more than Group l and postischemic mitochondrial swelling in Group III was more severe than Group I, and Group II.[p< 0.05] These results suggest that topical cold saline was the better method than topical ice slush or topical ice chip as a myocardial preservation modality in the isolated rat heart model of cardiopulmonary bypass.