• Korean Journal of Plant Taxonomy
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• v.43 no.3
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• pp.181-187
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• 2013

Genetic variation in Asaum misandrum, a woodland herb in Korea, was investigated based on allozyme analysis with starch gel electrophoresis. All of previously reported populations in Korea were sampled and seven loci from six enzymes were analyzed. Overall genetic variation of A. misandrum population showed considerably high levels of genetic variation within the species (A = 2.05, P = 71.4, $H_E$ = 0.294). A positive $F_{IS}$ value of A. misandrum indicated overall deficiency of heterozygotes, and a low $F_{ST}$ value (0.112) meant very little differentiation among populations. Factors contributing to the high levels of genetic diversity found within populations of A. misandrum include population maintenance via wide distribution range from Korea to Japan and primarily outcrossing breeding system. Although it showed moderate genetic diversity level, most habitats of the species were scattered and discontinuous. Besides, low numbers of individuals were found in the most habitats and individuals are collected frequently from the wild due to the unique shape of the flowers as well as the rarity of the species. Thus, there is a need to set up a reasonable conservation strategies including the maintenance mechanism of genetic diversity of A. misandrum.

• Korean Journal of Agricultural and Forest Meteorology
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• v.3 no.1
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• pp.30-36
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• 2001

Schisandra nigra Max. has been cultivated far a medical use as well as food. It is an endemic species which has a unique habitat at the altitude of 600-1,400 m in Cheju island. In this study, three natural populations of S. nigra were investigated by using of starch-gel electrophoresis to determine the extent and distribution of genetic diversity. Except 2 monomorphic locus (Mdh-2 and Pgi-1), 4 of the 6 isozyme locus (Idh, Mdh-2, Mnr, and Pgi-2), verified from 4 isozymes, revealed polymorphism in the three populations of S. nigra. The mean number of allele per locus was 1.7 and the percentages of polymorphism loci were 38.9% at 95% level and 50% at 99% level respectively. The observed and estimated heterozygosities were 0.141 and 0.147 respectively. Although plants which were in the face of crisis and distributed in the restricted area, have been known to the very low degree of genetic variation, S. nigra showed higher genetic variation than others. Genetic variation was mostly allocated within population and individuals than that among populations. The result of Wright's F analysis estimates of $F_{IT}$ and $F_{IT}$ showed that S. nigra population revealed Hardy-Weinberg steady state.

• Korean Journal of Agricultural Science
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• v.15 no.2
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• pp.153-163
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• 1988

This experiment was carried out to obtain the thermophilic fungus producing amylase and to investigate properties of the amylase. The selected strain, L-11 was obtained from soil in the vicinity of a hot spring and identified as Mocor sp.. And then the conditions for enzyme production in wheat bran cultures and properties of the crude enzyme were investigated. Furthermore, the enzyme was purified and the characteristics of purified enzyme were studied. The results obtained were as follows: 1. On the wheat bran medium added 80-100% water, amylase was effectively produced by the selected strain, L-11 for 48 hrs incubation at $50^{\circ}C$. 2. When the crude enzyme solution of the strain L-11 was passed through DEAE-Sephadex A-50 column chromatography, two peaks having amylase activity were obtained, and one peak was that of the main enzyme (enzyme of B peak). 3. The purified enzyme (enzyme of B peak) was recognized as single protein band on polyacrylamide disc gel electrophoresis. 4. In the hydrolysis reaction of soluble starch by the enzyme of main amylase, oligosaccharides produced at early stage were maltose and maltotriose mainly and procedure of the reaction maltose amount of maltose and glucose was increased. 5. The strain L-11 was recognized as a special strain producing ${\alpha}-amylase$ mainly and scarcely glucoamylase. 6. The optimum pH, optimum temperature, pH stability, and temperature stability of ${\alpha}-amylase$ were pH 4.0, $60-65^{\circ}C$, pH 4.0-9.0, and below$70^{\circ}C$.

• The Korean Journal of Mycology
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• v.6 no.2
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• pp.1-10
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• 1978

In de novo biosynthesis of the extracellulor enzymes-proteinsaes, alpha and gluc-amylases during the synchronized differentiation of Aspergillus niger in submerged culture and surface liquid culture were investigated. Gluc-amylase was synthesized in the stage of presporulation in which phialide formation is involved. Proteinase was synthesized both in the stages of conidiophore formation and presporulation. Alpha-amylase was synthesized during presporulation and sporulation stages, the activity of enzyme lasted for seven days on surface liquid culture. It seemed that the synthesis was occured in de novo partly repressed by the catabolite, and its nature was found to be constitutive since it is produced in non-starch medium. Polyacrylamide gel electrophoresis have shown that presporulating and sporulating body produced diverse types of the proteins whereas the earlier stages of vegetative body showed simpler profiles. The uptake of C-14 uracil into RNA and C-14 glutamate into protein were shown to be vigorous in presporulating body rather than those in sporulating body. Coincidence of alpha-amylase biosynthesis in de novo and sporulation may be significant in the study of differentiation in which gene expression is involved.

• Journal of Korean Society of Forest Science
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• v.58 no.1
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• pp.1-7
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• 1982

Megagametophyte and embryo tissue of Pinus densiflora were subjected to study the inheritance of glutamate-oxalate transaminase(GOT) and leucine aminopeptidase(LAP), and linkage relationship among isozyme loci coding both enzymes by starch gel zone-electrophoresis. Four zones of activity were observed for GOT. No variation was found in the fastest migrating zone (GOT-A). Electrophoretic phenotypes of the other two zones (GOT-B and GOT-C) showed 1:1 segregation ration, suggesting that each zone is controlled by a single locus. Foru and three alleles were identified at both loci respectively. The isozyme pattern of the fourth zone(GOT-D), migrated cathodally, coincided precisely with that of GOT-C. Whether the two zones are controlled by the same locus or by two tightly linked loci remained unknown. In all three variant GOT zones, heterozygoes embryos produced triple band patterns, indicating that GOT isozyme in Pinus densiflora is a dimer. Two zones of activity stained for LAP were found. The segregation of the two zones (LAP-A and LAP-B) suggested that tow loci control each of both isozymes. Two and three alleles were identified at both loci. GOT-B and LAP-B were found to be tightly linked, showing an average recombination frequency of 12.5 percent. Slight deviation from independent assortment was observed between GOT-B and GOT-C, with recombination frequency of 41 percent.