• Korean Journal of Plant Tissue Culture
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• v.25 no.4
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• pp.283-288
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• 1998

The bialaphos is a potent inhibitor of glutamine synthease in higher plants and is used as a non-selective herbicide. We have used the bialaphos resistant gene(Bar) encoding for an acetyltransferase isolated from Streptomyces hygroscopicus SF1293. Callus derived from mature seeds of rice(Oryza sativa L. cv. Dong Jin) were co-cultivated with Agrobacterium tumefaciens EHA101 carring a plasmid pGPTV-HB containing genes for hygromycin resistance (HygR) and Bar. Transgenic plants showing in vitro resistance to 50 mg/L hygromycin and 10 mg/L bialaphos were obtained by using a two-step selection/regeneration procedure. Transformation efficiency of rice was about 30% which was as high as reported in other dicotyledons. Progenies ($\textrm{T}_{1}$ generation) derived from primary transformant of 17 lines were segregated with a 3 resistant : 1 sensitive ratio in medium containing hygromycin and bialaphos. Stable integration of Bar gene into chromosomal DNA was proven by Southern blot analysis of genomic DNA isolated from $\textrm{T}_{2}$ progenies. Transgenic plants ($\textrm{T}_{3}$) grown in the field were resistant to bialaphos (Basta) at a dosage lethal to wild type plants.

• Korean Journal of Plant Tissue Culture
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• v.25 no.3
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• pp.207-217
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• 1998

Total of 78 strains were characterized based on the morphological characteristics of colonies isolated on Schroth, and New & Kerr's media for selection of hypervirulent wild-type Agrobacterium spp from galls, hairy root-like process and soil of Populus, Malus, Salix and Diopyros in Korea. Among them, 48 strains were able to induce tumors in carrot disc. Hypervirulent A. tumefaciens SP101 and SM042 were identified as biotype 1 and biotype 2, respectively, These strains formed fast growing, larger tumors as compared to those induced by other strains. The binary vector pGA643 with kanamycin resistant gene was mobilized from E. coli MC100 into A. tumefaciens strain SM042 isolated from soil, and/or disarmed vector PC2760 using a triparental mating method with E. coli HB101/pRK2013, and transconjugants, A. tumefaciens SM643 and PC643 were obtained in minimal media containing kanamycin and tetracycline. Tobacco tissues were cocultivated with conjugant Agrobacterium and then transferred to selective medium with 2,4-D and kanamycin to induce the transformants. Calli were formed more efficiently in cocultivation with A. tumefaciens SM643 than that with A. tumefaciens PC643. Most of calli transformed with A. tumefaciens PC643 were friable and regenerated into normal plantlets, while the calli transformed with A. tumefaciens SM643 were compact, hard, and mixed with friable calli. The friable calli formed normal shoots, while compact calli did not form shoots but only grew to typical compact tumor calli. When the shoots formed directly from tobacco stems without callus induction after transformation by A. tumefaciens SM643 with wild-type Ti-plasmid, normal transformed plants can be induced without using disarmed Ti-plasmid.

• Korean Journal of Plant Tissue Culture
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• v.28 no.2
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• pp.103-108
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• 2001

The in vitro plantlets of cassava (Manihot esculenta Crantz cv. MColl 22) could be regenerated from nodal explant cultures in a liquid MS basal medium containing 0.01 mg/L zeatin for 2 weeks. The plantlets of 1.5∼2.5 cm in shoot length were transplanted to a glass bottle containing fine sand and acclimated under non-sterile conditions after excising their intact roots by: 1) prune leaving roots base of 1∼1.5 cm; 2) complete removal of roots; and 3) cutting off the rooting zone. The majority of in vitro-formed intact roots continued growth after transferred to soil, and all of the damaged roots stopped further growth. The plantlets with excised roots began to develop new roots within 7∼10 days after being transferred to a glass bottle, and a few of the pruned roots developed lateral roots from the remaining portion. Pruning and removal of in vitro roots resulted in a high survival rate (>87%), and did not significantly affect ex vitro root regeneration and acclimation, but the plantlets in which the rooting zone had been cut-off showed 73% survival rate. Pruning or removal of in vitro roots before transfer of plantlets is recommended for useful method of commercial micropropagation because of easier handling and high survival rate of plantlets.

• Korean Journal of Plant Resources
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• v.32 no.5
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• pp.415-422
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• 2019

Rhodosporidium toruloides has been known as an in vitro model of fat metabolism. The purpose of this study is to identify the triglyceride inhibitory effects of hot water extracts from beetroot using R. toruloides. The triglyceride content of oleaginous yeast cultured from YPD culture medium were regulated by treatment of beet root hot water and ethanol extract, respectively. In addition, the number of cells in the oleaginous yeast was 10.48, 8.46, 12.40, 12.80 and $8.24{\times}10^3cell/mL$. The treatment of hot water extract of beet root increased total lipid content of oleaginous yeast in dose dependently. Moreover, the triglyceride content of oleaginous yeast was decreased by hot water extract of beet root extract, respectively. The fat droplet in the oleaginous yeast decreased according to the concentration of hot water extracts from beetroot. The ratio of increase in the number of cells in the oleaginous yeast were increased dose-dependently by treatment of hot water extract from beetroot compared with control group. The free fatty acid and total carotenoid contents were increased concentration-dependently by treatment of hot water extracts from beetroot. These study results indicate that hot water extracts from beetroot has a triglyceride inhibitory effects.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.1
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• pp.15-24
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• 2005

Enterobacter intermedium oxidizes glucose to gluconic acid and sequentially converts gluconic acid to 2-ketogluconic acid (2-KGA) under aerobic condition. Shaking incubation of E. intermedium in a broth medium containing 22.5 g glucose, 8.2 g gluconic acid and 40 g rock phosphate per liter resulted in $1028mg\;L^{-1}$ soluble phosphate. The culture broth was used as phosphate bio-fertilizer (PBF) in this experiment. To evaluate PBF produced by E. intermedium on lettuce growth, five treatments (PBF1/3, PBF2/3, PBF3/3, BP, and MF) were used. In MF and BP treatments, $P_2O_5$ 5.9 kg of mineral fertilizer per 10a was added, while in PBF1/3, PBF2/3, and PBF3/3 treatments, culture broth containing one third, two third, and same amount of soluble $P_2O_5$ 5.9 kg per 10a was applied, respectively. At 20, 35, and 50 days after transplanting of lettuce, plant growth components, biomass, enzyme activities and soil chemical properties were analyzed. Dehydrogenase activity and available phosphate concentration of rhizosphere in phosphate bio fertilizer treatments (PBF1/3, PBF2/3, PBF3/3) were generally higher compared to MF and BP treatments. Soil biomass in PBF3/3 treatment was significantly higher than MF and BP treatments at early growth stage. However, there was no significant difference among all treatments with time. Plant fresh weights in PBF1/3, PBF2/3, and MF treatments were better than those in BP and PBF3/3 treatments. However, in PBF2/3 treatment the highest fresh weight was discovered where alkaline phosphatase activity was generally higher than other treatments at 35 and 50 days. Enhancement of lettuce growth at 35 and 50 days in PBF2/3 treatment was associated with greater phosphate uptake in lettuce tissue. As regarding all results, PBF showed better lettuce growth compared to mineral phosphate fertilizer where PBF2/3 treatment resulted in increase of lettuce fresh weight by 23% and phosphate uptake by 50%.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.4
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• pp.235-244
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• 2004

In this study, we compared the levels of methylotrophic bacterial community diversity in the leaf samples of 19 rice cultivars collected from three regions of Korea. Nineteen pink pigmented isolates showing characteristic growth on methanol were obtained. Physiological and biochemical characters of each isolate were examined according to methods described in Bergey's Manual of Systematic Bacteriology. When phylotypes were defined by performing numerical analysis of 37 characteristics, four distinct clusters were formed. The two reference strains, Methylobacterium extorquens AM1 and Methylobacterium fujisawaense KACC10744 were found to group under cluster IV and cluster III respectively. Cluster I diverged on the basis of nitrate reduction and four isolates showed tolerance upto 0.5 M NaCl concentrations. Two strains in cluster I and III were found to possess methane utilizing properties. Most of the isolates in all the four clusters utilized monosaccharides, disaccharide and polyols as carbon source. When the isolates were subjected for indole-3-acetic acid (IAA) analysis in the presence of L-tryptophan, only 8 isolates exhibited IAA production. In addition, the nitrogen source in the medium was found to influence the IAA production. Addition of $(NH_4)_2SO_4$ in the medium led to a 2 to 30 fold increase in the indole synthesis. However, $KNO_3$, $NH_4NO_3$ and $NH_4Cl$ substitution did not significantly stimulate the synthesis of IAA in the growth medium. Result of gnotobiotic root elongation assay significantly increased roots and shoots lengths, and number of lateral roots, which is mediated by IAA production in the culture medium. The rice seedlings primary roots from seeds treated with methylotrophic isolates were on average 27 to 56% longer than the roots from seeds treated with the uninoculated seeds. In addition, application of different high concentrations of authentic IAA ($400g\;mL^{-1}$) to roots of rice seedlings inhibited root growth. However, the IAA concentration from 10 to $200g\;mL^{-1}$, IAA promoted root growth of rice seedlings. These results suggest that bacterial IAA plays a major role in the development of the host plant root system.

• Applied Biological Chemistry
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• v.37 no.3
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• pp.182-188
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• 1994

Similar to the $^{42}K$ uptake, $^{86}Rb$ uptake by the roots of Hordeum distichum grown in the hydroponic culture was negatively correlated with the concentration of K supplied previously, showing that $^{86}Rb$ can be used for the K-bioassay. $^{86}Rb$ having longer half life (18.86 day) than $^{42}K$ (12.36 hr) allowed the use of larger number of root samples. $^{86}Rb$ uptake of 3 years old Citrus unshiu Marc. grown in water culture decreased drastically with the increase of K concentration of the culture solution, thus demonstrating that the nutrition status of K for citrus trees can be diagnosed by K-bioassay using $^{86}Rb$ tracer. $^{86}Rb$ uptake by the excised roots of Hordeum distichum grown in the pot with different K fertilizations was well correlated with the exchangeable K in soil. The amount of exchangeable K in soil for the optimal plant growth can be determined by its relationship. $^{42}K$ and $^{86}Rb-uptake$ by the Hordeum distichum roots were markedly inhibited by $5{\times}10^{-3}\; M$ KCN in the bioassay solution, indicating that uptake is energy-dependent. There was no significant relationship between K content in citrus leaves and K concentration in the water-culture medium. It is concluded that K-bioassay is a potentially useful tool for determining of K requirement in citrus trees.

• Journal of Bio-Environment Control
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• v.27 no.1
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• pp.1-6
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• 2018

Also, t-cincreaseisdecreasein order In hydroponics, the accumulation of inorganic ions in the root zone are closely related to the irrigation volume. Therefore, the effects of irrigation volume on the growth and yield of tomatoes are very signigicant. This study was conducted to investigate the effect of irrigation volume on inorganic ions of root zone in hydroponic culture using coir substrate. The irrigation volume was adjusted to 4 levels depending on the integrated solar radiation for each growth period. The drainage ratio was calculated by daily amount of irrigation and drainage. The higher irrigation volume is, drainage ratio and water absorption tended to increase. But, the water absorption in the treatment of high irrigation volume was decreased in February and March compared to the treatment of medium high irrigation volume. By calculating monthly average irrigation volume and the drainage ratio, 120 to 1$40J/cm^2$ in January, 100 to $120J/cm^2$ in February, 80 to $100J/cm^2$ in March, 70 to $90J/cm^2$ in April and 60 to $75J/cm^2$ in May was detected as appropriate irrigation volume ranges which drainage ratio was 20-30%. The higher irrigation volume, the lower the concentration of ions decrease, which could prevent the accumulation of nutrients in the root zone. However, due to the characteristics of the coir substrate that absorbs ions, concentration of ions was significantly high when the drainage ratio was 20-30%. However, concentrations of P and K were sometimes lower in the drainage than that of irrigation water regardless of the treatment. Mg and S were the most highly accumulated ions even in the treatment of high irrigation volume. In low radiation season, there was no difference in the ion concentration in the drainage depending on the irrigation volume. In high radiation season, the lower irrigation volume, resulted to the higher ion concentration in the drainage. After March, it was difficult to prevent the increase of ions concetration in the drainage by only adjusting irrigation volume. Thus, it is necessary to decrease the EC of irrigation solution to prevent the accumulation of nutrients in the root zone.

• Journal of Korean Society of Forest Science
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• v.78 no.4
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• pp.333-344
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• 1989

The objectives of this study were to investigate the growth of Gyrophora esculanta and to establish a method of tissue culture of the plant. The results obtained were as follows : 1. The Gyrophora esculanta was found growing mostly on the rock slopes of 722 m to 1915 min elevation on mountains in Korea. 2. Trees growing in the vicinity of the G. esculanta were mainly Quercus spp., Pinus thunbergii, Acer spp. and Lespedeza spp, Especially Quercus spp. was found growing in all of the study site. 3. The average Length of the rock slopes with G. esculanta growing on was 14 m and their aspects were mostly south. 4. The G. esculanta were found growing on rocks of Crystalline Schist, Quartz, Liparite, Granite, ete. Particularly they were mostly found on granites. The gradient of the rock slopes was in the range of 22-90 degrees. 5. The mean number of individuals of G. esculanta per one rock slope ranged from 14 at Mt. Bukhan to 70 at Mt. Jrri. Their mean diameter ranged from 1.8cm at Mt. Munsu to 4.6cm at Mt, Sokri. 6. The average percentage of G. esculanta with fruit body was 17.6%. The highest value was found at Mt. Cheonhwang (24.0%). 7. When the 100 segments of rhizoid of Gyrophora esculanta cultured in Detmer's medium supplemented with kinetine 5mg/l and 2, 4-D 3mg/l, n callus of microspore origins were induced from about 20% of the segments. As the induced n callus was transplanted on the six different types of rocks, it was observed that the juvenile G. esculanta grew best on granite and the development rate of G. esculanta on the granite was about 55%.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.31 no.1 s.49
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• pp.97-102
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• 2005

One of the key molecules involved in skin moisture is hyaluronan (hyaluronic acid, HA) with its associated water of hydration. The predominant component of the ECM (extracellular matrix) of skin is HA. It Is the primordial and the simplest of the GAGs (glycosaminoglycans), a water-sorbed macromolecule In extracellular matrix, Included between the vital cells of epidermis. In the skin, HA was previously thought to derive extlusively from dermis. But, recent studies revealed that HA could be synthesized in epidermis. Flavonoids are polyphenolic compounds that is found mainly in foods of plant origin. Kaempferol was known to increase glutathione synthesis in human keratinocyte. And quercetin blocked PPAR-meidated keratinocyte differentiation as lipoxygenase inhibitors. In this study, we sought to evaluate the effect of flavonid, kaempferol and quercetin on production HA in keratinocyte. We examined the changes of three human hyaluronan synthase genes (HASI, HAS2, HAS3) expression by semi-quantitative RT-PCR when kaempferol or quercetin was added to cultured human keratinocytes. We found that these flavonoids slightly upregulated HAS2, HAS3 mRNA after 24 h. And we investigated the effect on HA production by ELISA. When we evaluated the level of HA in culture medium after 24 h incubation. We found enhanced accumulation of HA in the culture medium. Although the effects of above flavonoids are less than retinoic acid, the data indicate that kaempferol, quercetin can dose-dependently increase the level of HA in epidermis cell line. It suggested that flavonoid, kaempferol, and quercetin increased production of HA in skin and it helped to elevate skin moisture and improve facial wrinkle.