• Journal of Life Science
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• v.8 no.4
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• pp.410-415
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• 1998

Procine pepsin hydrolysis of hexapeptide L-S-pNF-Nle-A-OMe in the presence of dipeptide L-L generates a new peak on HPLC analysis of reaction mixtures that is not seen when enzyme is incubated with either peptide alone. The peaks can be detected spectroscopically at either 214 or 254 nm, the latter consistent with a new peptide containing the p-nitro-F residue. The data suggest acyl transpeptidation between E(L-S-pNF) and L-L to form L-S-pNF-L-L. Consistent with this inference are (1) the ability of L-L-NH$_{2}$ and inability of Boc-L-L to undergo a similar transpeptidation reaction, and (2) the data from electrospray mass spectrum. This synthesis requires that Nle-A-L-OMe be released before L-S-pNF, an order opposite to that proposed on the basis of product inhibition kinetics. Consistent with this inference are reciprocal solvent isotope effects ; normal isotope effects of 1.736$\pm$0.121 on the formation of Nle-A-L-OMe and 2.281$\pm$0.184 in the formation of L-S-pNF, coupled to an inverse isotope effects of 0.576$\pm$0.045 on the formation of L-S-pNF-L-L. Because transpeptidation precedes faster in D$_{2}$O, the isotopically-sensitive step must occur after release of Nle-A-L-OMe. Isotopically-enhanced transpeptidation is consistent with the Uni-Bi iso memchanism postulated on the basis of an isotope effects on Vmax but not on Vmax/Km$^{1)}$ and confirmed by isotope effects on the onset of inhibition by pepstatin$^{2)}$.

• Korean Journal of Plant Tissue Culture
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• v.21 no.5
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• pp.281-286
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• 1994

The hormonal regulation of organ differentiation was investigated in the tissue culture of sweet potato. Embryogenic callus was induced from shoot tips cultured on MS medium supplemented with 1 mg/L 2,4-D. When embryogenic callus was transferred to medium containing 0.1 mg/L GA$_4$, it proliferation was stimulated. The callus gave rise to plantlets when cultured on medium containing 0.1 mg/L BA. Addition of 0.1 mg/L jasmonic acid or 0.01 mg/L brassinolide to medium was effective for the development of healthy normal plantlets.

• Korean Journal of Plant Tissue Culture
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• v.25 no.4
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• pp.267-271
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• 1998

Cotyledon explants of lettuce were cocultured with Agrobacterium tumefaciens LBA4404::pBKS-GR1 harboring glutathione reductase(GR) gene in MS medium supplemented with 0.1 mg/L NAA and 1.0 mg/L 2ip for 48 hr. These explants were transferred to MS medium supplemented with 0.1 mg/L NAA and 1.0 mg/L 2ip, 50 mg/L kanamycin, and 500 mg/L carbenicillin. After 4 weeks of subculture, kanamycin-resistant shoots were obtained on selection medium. Leaves of putative transformants survived on selection medium containing 100 mg/L kanamycin. Incoporation of the GR gene into lettuce was confirmed by PCR analysis of genomic DNA. Southern blot analysis showed that ECL-labeled GR gene was hybridized to the expected amplified genomic DNA fragment of about 1.8 kb from transgenic lettuce. The presence of mRNA in transgenic lettuce was confirmed by RT-PCR with total RNA of transgenic lettuce. In progeny test of transformants, R$_1$ seeds were resistant to kanamycin (200mg/L) on MS medium.

• Bulletin of the Korean Chemical Society
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• v.4 no.2
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• pp.92-95
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• 1983

The addition products of glutathione to ${\beta}$ -nitrostyrene derivatives were synthesized. ${\beta}$ -Nitrostyrene (1a), p-methyl-${\beta}$-nitrostyrene (1b), 3,4,5-trimethoxy-${\beta}$-nitrostyrene (1c), o-, m- and p-chloro-${\beta}$-nitrostyrene (1e, 1f, 1g) and o-, m- and p-methoxy-${\beta}$-nitrostyrene (1h, 1i, 1j) undergo addition reactions with glutathione to form S-(2-nitro-1-phenylethyl)-L-glutathione (5a), S-[2-nitro-1-(p-methyl)phenylethyl]-L-glutatione (5b), S-[2-nitro-1-(3', 4', 5'-trimethoxy)phenylethyl]-L-glutathione (5c), S-[2-nitro-1-(o-chloro)phenylethyl]-L-glutathione (5e), S-[2-nitro-1-(m-choro)phenylethyl]-L-glutathione (5f), S-[2-nitro-1-(p-chloro)phenylethyl]-L-glutathione (5g), S-[2-nitro-x-(o-methoxy)-phenylethyl]-L-glutathion e(5h), S-[2-nitro-x-(m-methoxy)phenylethyl]-L-glutathion e (5i), and S-[2-nitro-1-(p-methoxy)phenylethy])-L-glutathione (5j), respectively. The structure of adducts were identified by UV and IR-spectra, molecular weight measurement, and elemental analysis.

• Korean Journal of Microbiology
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• v.35 no.3
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• pp.237-241
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• 1999

Phenolic resin wastewater contained 41,000 mglI phenol, 2,800 mg/l fonualdehyde and various chlorinated phenolic compounds. Candida tropicalis PW-51 isolated [rom the natural enVlfooment was able to degrade 1,000 mg/l phenol in the presence of 100 mglI formaldehyde, but it took much time to degrade phenol with the increase of formaldehyde in phenolic resin wastewater. %en the phenolic resin wastewater was diluted to 1/40, the initial concentration of phenolic compounds (phenols) was 882 mglI and degraded to 81 mglI by C tfVpicalis PW-51 in batch culture. In a continuous biological treatment, the phenolic resin wastewater was diluted to 40 (745 mglI), 20 (1,356 mglI), or 10 (2,875 mglI) times. The removal efficiency of phenols in 1/40- and lI20-diluted phenolic resin wastewater was about 92%, but the phenols in 1!1O-diluted wastewater were not degraded. The remained phenols in wastewater were absorbed by a mixture of activated carbon and rice bran (1:1, v:v) in the process of absorption which was connected to the biological treatment. The total removal efficiency of phenols in 1!40~ and l/20-diluted phenolic resin wastewater was 99.9%.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.7
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• pp.1119-1125
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• 2004

The effect of hemicellulose extracted from soy fiber on the level of blood glucose and serum cholesterol in the streptozotocin-induced diabetic rat were investigated. The experimental plots were divided to cellulose group (control, 0.5％ hemicellulose group (H-l) and 1％ hemicellulose group (H-2) group. The groups were fed for 6 weeks, then fed for 1 week more after streptozotocin injection. Food intakes, weight gain and food efficiency ratio of H-2 group were higher, while water intakes and liver weight were lower than those of control and H-l group. The content of blood glucose and urine glucose were 212.8 mg/dL, 0.97 mg/dL in the control group, 160.5 mg/dL, 0.53 mg/dL in the H-l group, 141.0 mg/dL, 0.35 mg/dL in the H-2 group, respectively. There was no significantly difference in the content of neutral lipid, while the content of total serum cholesterol was 101.6 mg/dL in the control group, 73.8-78.4 mg/dL in the hemicellulose groups. The content of serum HDL-cholesterol in the all experimental groups showed no significantly difference showing 39.8-44.7 mg/dL. HTR and atherogenic index were 0.44 and 1.27 in the control group, but 0.54 and 0.46-0.85 in the hemicellulose groups, respectively.

• Horticultural Science & Technology
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• v.34 no.2
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• pp.249-256
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• 2016

This study was performed to investigate the effect of various concentrations of Diniconazole (DC) on the growth and quality of grafted tomato (Solanum lycopersicum) seedlings cultivated during the summer season. Concentrations of DC were set to 0 (non-treatment), 5, 10 and $20mg{\cdot}L^{-1}$, were treated once 3 days after grafting. Rootstock of the seedlings was shorter in the DC $5mg{\cdot}L^{-1}$ and $10mg{\cdot}L^{-1}$ treatment compared to the non-treatment, and the scions were significantly shorter in the DC $20mg{\cdot}L^{-1}$ treatment. Seedlings were significantly shorter in the DC $20mg{\cdot}L^{-1}$ treatment compared with the non-treatment. Leaf area was lower for seedlings subjected to all treatments than for seedlings in non-treatment group, and reduction was dose dependent. In particular, the DC $20mg{\cdot}L^{-1}$ treatment inhibited both leaf and stem growth. The fresh weighs of leaves and stems of the seedlings treated with DC $5mg{\cdot}L^{-1}$ and the fresh weights of roots subjected to all treatments were significantly greater than those of the non-treatment seedlings. Dry weight per organs of the seedlings treated with DC $5mg{\cdot}L^{-1}$ was significantly greater that of the non-treatment seedlings, but the dry weight of leaves of seedling treated with DC $20mg{\cdot}L^{-1}$ was much less than that of the non-treatment seedlings. The T/R ratio of the seedlings was lower for all treatments than for the non-treatment. The relative growth rate of the seedlings was significantly lower in the DC $20mg{\cdot}L^{-1}$ treatment and, the leaf area rate of seedlings was lower in the DC $5mg{\cdot}L^{-1}$ and $10mg{\cdot}L^{-1}$ treatment than in the non-treatment. Therefore, the optimal concentration of Dinoconazole used to produce a suitable grafted tomato seedling in the summer season is $10mg{\cdot}L^{-1}$ or less.

• Journal of Bio-Environment Control
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• v.18 no.2
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• pp.124-131
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• 2009

Surfactant polyvinyl alcohol (PVA-95) 1, 2, 4mg. $L^{-1}$ and calcium lignosulfonate (CLS) 5, 25, 50, 100mg. $L^{-1}$ were treated to the nutrient solution containing 1.0mg. $L^{-1}$ selenium (Se) to evaluate Se absorption effect using small DFT apparatus. The growth of leaf lettuce and pak-choi did not show unique significance by surfactant kinds and concentration in the tested range and physiological disorder. Vitamin C in leaves of two leafy vegetables was not significantly affected by surfactants also. Among major cations K content in pak-choi was highest in Se I+PVA-95 4mg. $L^{-1}$ treatment, and high in Se I+CLS 5 mg. $L^{-1}$ treatment. Ca content in two leafy vegetables showed increasing pattern by the two kinds of surfactants. Mg content was high in Se I+CLS 25mg. $L^{-1}$ treatment compared to control. Pak-choi absorbed Se about 10 times higher than leafy lettuce. Se content in leaves of two leafy vegetables increased by the treatment of two kinds of surfactants with the exception of CLS 100mg. $L^{-1}$ treatment.

• KSBB Journal
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• v.22 no.1
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• pp.1-6
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• 2007

The optimum liquid culture conditions were investigated for cell growth and polysaccharide production from liquid culture of Lentinus edodes. In flask culture, the optimal medium compositions for the polysaccharide production contained glucose 60 g/L, yeast extract 10 g/L, $KH_2PO_4$ 2.0 g/L, and $MgSO_4{\cdot}7H_2O$ 1.0 g/L. The maximum mycelial growth and polysaccharide production were 11.01 g/L and 1.64 g/L, respectively. In bioreactor, through the variation of aeration in order to increase mycelial growth and polysaccharide production, the maximum mycelial growth and polysaccharide production were 55.9 g/L at 8th day and 7.34 g/L at 7th day of cultivation with 1.5 vvm, respectively.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.69-72
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• 2000

After 300hours cultivation Chlorella vulgaris in standard medium in which the initial cell seeding concentration of $0.7{\times}10^4ells/mL$, $1.21{\times}10^5ells/mL$ was gained but in the case of 0.30g/L of initial cell seeding concentration the maximum growth rate of $0.162g/L\;{\cdot}\;day$ was shown. In the case of the initial glucose concentration of 2.00g/L, the cell concentration was changed from initial 0.025g cells/L to 0.874g cells/L after 140hours cultivation, the specific growth rate was $0.243h^{-1}$, but 268mL of gases were formed in 72hours, and after that, hydrogen evolution was completed. Formed gases were not all hydrogen, and 19.87 mol% of hydrogen is detected by GC. Analyzing the composition of Chlorella vulgaris by elementary analysis, it is found to be $C_{1.000}\;H_{1.774}\;N_{0.125}\;O_{0.557}$, and $CO_2$ conversion rate by Chlorella vulgaris was $0.616\;cells/g\;{\cdot}\;CO_2$