• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.6
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• pp.625-635
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• 1990

The purpose of this study was focused on investigation of biochemical properties of amylases in germinating corn(Zea mays L.) the amylase(I), (II) and (III) from germinating corn seeds were partially purified by ammonium sulfate precipitation, DEAE-Sephadex A-50 ion exchange column chromatography and Sephadex G-100 gel filtration. The last step was effective for separation of the corn amylases to a homogeneous slate. the purified amylase(I) was identified as a kind of $\alpha$-amylase from the fact that 5％ starch solution was hydrolysed into mainly maltose and maltotetrose by it, and amylase(II) and amylase(III) were enzymes producing maltotetrose as main product. The molecular weight and specific activity of the amylase(I), (II) and (III) were determined to be 54,000 and 70.47 unit/mg, 39,000 and 62.98 unit/mg, and 51,000 and 80.39 unit/mg, respectively. It showed a tendency to increase the amylases activities in presence of Ba, Ca, Co and Fe groups, but inhibits in that of Ag, Sn, Hg and Zn groups, and amylase(I), (II) and (III) remained stable at pH 5-6 and 2$0^{\circ}C$ for 40 days in containing of 1 mM CaCl$_2$. The optimum pH and optimum temperatures were pH 6, pH 5 and pH 6 and 35$^{\circ}C$, 55$^{\circ}C$ and 55$^{\circ}C$, respectively. These results suggest that the amylase(I), (II) and (III) were different amylases.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.8
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• pp.1045-1050
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• 2006

Optimum operation condition for pilot scale of alkaline processing for fish muscle was investigated by measuring protein solubility, yield, texture, and water-holding capacity. Recovered protein yield was 33.2% for whole fish and 61.8% for minced muscle. Optimum homogenized speed and time, using industrial scale homogenizer, were 3,000 rpm and 5 min, respectively. Limited centrifugal force of continuous cylinder type was 4,000 rpm for recovering soluble protein, and 2,000 rpm for recovering precipitated proteins. The pH control agents such as citric acid, sodium phosphate and calcium oxide decreased the breaking force and deformation of recovered protein gel. The breaking force and deformation of the recovered proteins were high compared to conventional surimi. The breaking force and deformation were decreased by addition of salt, starch and bovine plasma proteins. Whiteness of recovered protein gel was lower than that of conventional surimi. Alkaline processing greatly decreased nitrogen content and chemical oxygen demand in waste water. The results suggest that alkaline processing has a potential as industrial production for recovering the proteins from fish muscle.

• Journal of Life Science
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• v.20 no.5
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• pp.683-690
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• 2010

The yeast strains of Saccharomyces diastaticus produce one of three isozymes of an extracellular glucoamylase I, II or III, a type of exo-enzyme which can hydrolyse starch to generate glucose molecules from non-reducing ends. These enzymes are encoded by the STA1, STA2 and STA3 genes. Another gene, sporulation-specific glucoamylase (SGA), also exists in the genus Saccharomyces which is very homologous to the STA genes. The SGA has been known to be produced in the cytosol during sporulation. However, we hypothesized that the SGA is capable of being secreted to the extracellular region because of about 20 hydrophobic amino acid residues at the N-terminus which can function as a signal peptide. We expressed the cloned SGA gene in S. diastaticus YIY345. In order to compare the biochemical properties of the extracellular glucoamylase and the SGA, the SGA was purified from the culture supernatant through ammonium sulfate precipitation, DEAE-Sephadex A-50, CM-Sephadex C-50 and Sephadex G-200 chromatography. The molecular weight of the intact SGA was estimated to be about 130 kDa by gel filtration chromatography with high performance liquid chromatography (HPLC) column. Sodium dedecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis showed it was composed of two heterogeneous subunits, 63 kDa and 68 kDa. The deglycosylation of the SGA generated a new 59 kDa band on the SDS-PAGE analysis, indicating that two subunits are glycosylated but the extent of glycosylation is different between them. The optimum pH and temperature of the SGA were 5.5 and $45^{\circ}C$, respectively, whereas those for the extracellular glucoamylase were 5.0 and $50^{\circ}C$. The SGA were more sensitive to heat and SDS than the extracellular glucoamylase.

• Journal of Korean Society of Forest Science
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• v.64 no.1
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• pp.20-25
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• 1984

The inheritance of isoenzymes in young coat tissues of trembling aspen (Populus tremuloides Michx.) was studied by electrophoretically analysing five parental clones and their full-sib progenies obtained by crossing one female clone to four male clones. The distal 2cm section of vigorous young roots of 70 seedlings per family were subjected to horizontal starch gel electrophoresis. The resulting gels were tested for activity of 7 enzyme systems. Evidences for the inheritance of isoenzymes observed indicated that the isoenzyme variants of every isoenzyme zone were under control of codominant alleles at a single locus. Chi-square test of joint segregation data of the two loci, 6-PGD-2 and PGI-2, indicated that the pair of loci was not linked.

• Journal of Life Science
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• v.23 no.6
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• pp.728-735
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• 2013

Plantago asiatica (Plantaginaceae) is a wind-pollinated plant that grows mainly on fields in East Asia. Starch gel electrophoresis was used to investigate the allozyme diversity and population structure of 18 populations of this species. Although the plantain populations were isolated and patchily distributed, they maintained a high level of genetic diversity; the average percentage of polymorphic loci was 57.1%, the mean number of alleles per locus was 2.07, and the average heterozygosity for 18 populations was 0.201. The combination of a predominant wind-pollinated, mix-mating reproduction, large population sizes, high gene flow between subpopulations, and a propensity for high fecundity may explain the high level of genetic diversity within populations. A direct gradient in overall genetic diversity is associated with latitude. Genetic diversity of P. asiatica is markedly decreased from $35^{\circ}3^{\prime}$ to high latitude and decreased from $35^{\circ}3^{\prime}N$ to low latitude, whereas there does not show a longitudinal gradient in genetic diversity.

• Journal of Korean Society of Forest Science
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• v.85 no.3
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• pp.409-415
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• 1996

Isozyme variations in 4 enzyme systems in Pinus densiflora for. multicaulis in 31 individual trees collected throughout the country were studied by starch gel electrophoresis using haploid megagametophyte tissue to compare with those of Pinus densiflora. A minimum of 7 loci were found to code for isozymes of the enzyme systems. No variation was found at locus GOT-A; at the remaining 6 variable loci(GDH-A, GOT-B, GOT-C, IDH-A, LAP-,A, LAP-B) and 2 to 4 alleles were identified. We could not find any marker alleles to distinguish Pinus densiflora for. multicaulis from Pinus densiflora at the isozymes studied here. Allele frequency distributions at each loci were almost all the same as those of P. densiflora. The percentage of polymorphic loci(99% level), the number of alleles per locus, the observed and expected heterozygosities were 85.7, 2.3, 0.165 and 0.186%, respectively. The level of genetic diversity in Pinus densiflora for. multicaulis seemed to be less than that of P. densiflora.

• Animal Systematics, Evolution and Diversity
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• v.11 no.2
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• pp.207-221
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• 1995

Electrophoretic analysis was performed to determine the interspecific genetic relationships of the genus Raja collected in Korea waters. We confirmed 5 species [Raja (Okamejei) meerdervoortii Bleeker, R.(O).acutispina Ishiyama, R.(O) kenojei Muller et Henle, Raja (Dipturus) kwangtungensis Chu, and R.(D.) pulchra Liu] inhabting in Korea. As results of starch gel electrophoresis, 24 genetic loci were obtained from 13 enzymic and non-enzymic proteins, and allele frequencies of each locus were calculated . Even thought their various dorsal color patterns, the mean genetic similarity among 4 conspecific populations of R.(O) kenojei showed highly close genetic relationships (S=0.966) R.(O) kenojei and R.(D) kwangtungensis which belong to different subgenus , revealed subspecific level of differentiation (S=0.829). R. (Diptuuus ) kwangtungensis was genetically much closer to Raja(Okamejei) species than to Raja (Dipturus) species group. R.(O) acutispina and R.(D) kwangtungensis were unrecorded species to Korea.

• Animal Systematics, Evolution and Diversity
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• v.13 no.3
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• pp.233-246
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• 1997

A genetic analysis using starch gel electrophoresis was performed to clarify the degrees of genetic differentiation and the phylogenetic relationships among four species of the genus Corbicula (Bivalvia, Corbiculidae). The average genetic similarity coefficients among the populations of each species on C. fluminea, C. leana and C. colorata were very closed (Rogers' S$\geq$0.970), whereas the other C. japonica was separated into two genetic groups (S=0.873) with distinct allelic difference at the Gpl locus. Thuefore additional taxonomic studies are needed on this species. On the other hand, these four species were well distinguished from each other genetically with distinct allelic differences at 4 to 9 loci. The genetic similarity coefficients (S) between C. leana and C. colorata, C. fluminea and C. leana, and C. fluminea and C. colorata were 0.737, 0.689, and 0.594, respectively. In particular, the average genetic similarity coefficients between these three species (inhabiting in freshwater) and the other C. japonica (inhabiting in brackishwater) were notably lower (S=0.370).

• Korean Journal of Veterinary Research
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• v.34 no.3
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• pp.487-492
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• 1994

The study was conducted to investigate the phenotypes of blood proteins, hemoglobin and albumin, of 104 German shepherds in Dag-gu, Yae-chum Kim-hae and Kwang-ju area by the starch gel electrophoresis. The results obtained were summarized as follows: 1. The hemoglobin phenotypes were observed three(HbBB, HbBb and Hbbb). Fast migrating bands were same and slow migrating bands were divided by heavy(HbBB), light(HbBb) and non-stained(Hbbb). The frequencies of appearance in HbBB, HbBb and Hbbb were 17.31%, 51.92% and 30.77%, respectively. 2. The hemoglobin phenotypes were controlled by two allelic genes, $Hb^b$ and $Hb^B$. The gene frequencies were calculated at 0.567 in $Hb^B$ and 0.433 in $Hb^A$. 3. The albumin phenotypes were observed three(AlbFF, AlbSS and and AlbFS), which were divided by fast migrating band(AlbFF), slow migrating band(AlbSS) and mixed migrating band(AlbFS). The frequencies of appearance in AlbFF, AlbFS and AlbSS were 5.77%, 28.85% and 65.38%, respectively. 4. The albumin phenotypes were controlled by two alleic genes, $Alb^F$ and $Alb^S$. The gene frequencies were calculated at 0.202 in $Alb^F$ and 0.798 in $Alb^S$.

• Journal of Microbiology and Biotechnology
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• v.24 no.2
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• pp.254-263
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• 2014

Enteromorpha polysaccharides (EP) extracted from green algae have displayed a wide variety of biological activities. However, their high molecular weight leads to a high viscosity and low solubility, and therefore, greatly restrains their application. To solve this problem, bacteria from the surface of Enteromorpha were screened, and an Alteromonas macleodii strain B7 was found to be able to decrease the molecular weight of EP in culture media. Proteins harvested from the supernatant of the A. macleodii B7 culture were subjected to native gel electrophoresis, and a band corresponding to the Enteromorpha polysaccharide lyase (EPL) was detected by activity staining. The enzyme identity was subsequently confirmed by MALDI-TOF/TOF mass spectrometry as the putative ${\alpha}$-amylase reported in A. macleodii ATCC 27126. The amylase gene (amySTU) from A. macleodii B7 was cloned into Escherichia coli, resulting in high-level expression of the recombinant enzyme with EP-degrading activity. AmySTU was found to be cold-adapted; however, its optimal enzyme activity was detected at $40^{\circ}C$. The ${\alpha}$-amylase was highly stable over a broad pH range (5.5-10) with the optimal pH at 7.5-8.0. The highest enzyme activity was detected when NaCl concentration was 2%, which dropped by 50% when the NaCl concentration was increased to 16%, showing an excellent nature of halotolerance. Furthermore, the amylase activity was not significantly affected by tested surfactants or the presence of some organic solvents. Therefore, the A. macleodii strain B7 and its ${\alpha}$-amylase can be useful in lowering EP molecular weight and in starch processing.