• Journal of Plant Biology
• /
• v.39 no.1
• /
• pp.31-40
• /
• 1996

The physiological and biochemical characterizations of the ethylene-related mutants in Arabidopsis thaliana - ethylene overproducing mutant (eto1-l) and ethylene insensitive mutants (etrl-3, ein2-l) - were detailed in this studies. Two or three week.old mature rosette leaves (before bolting) were used as the plant materials. Ethylene productions of eto1-l, etrl-3, and ein2-l mutants were about 200%, 400%, and 450% compared to that of wild type, respectively. ACC synthase and ACC oxidase activities of eto1-l mutant were similar to those of wild type. ACC content and ACC N-malonyltransferase activity, however, were 4.5 times and 3 times higher than those of wild type, respectively. SAM synthetase activity increased by 50% in eto1-l mutant plant. These results indicated that the alteration in the eto1-l mutant occured before the step of the conversion of SAM to ACe. In etrl-3 and ein2-l mutants, ACC synthase activities increased, but ACC oxidase activities decreased. ACC content and ACC N-malonyltransfcrase activity were 2 times higher than those of wild type. SAM synthetase activity in etrl-3 is similar to those of wild type, while it increased by 73% in ein2-l. These results showed that the block in ethylene action affected the autoregulation of ethylene biosynthesis, so that ACC synthase activity was not autoinhibited and ACC oxidase activity was not auto stimulated by ethylene. When the leaf tissues were used for in vitro kinase assay, a cytosolic protein (approximately 36 kDa) was phosphorylated only in eto1-l and ein2-l mutants.utants.

• Reproductive and Developmental Biology
• /
• v.39 no.1
• /
• pp.13-21
• /
• 2015

The importance of genetic resource preservation has been highlighted in the literature as a means of maintaining genetic diversity. Investigations for hematologic values and the differential count of white blood cell count (WBC) for Korean indigenous cattle (KIC) and endangered indigenous cattle (EIC) are rarely performed. Therefore, the objective of this study was to investigate the hematologic values of total 40 EIC (White, Black, Mini cattle) and 35 KIC as control by analysis of hematologic characteristics. As a result, the mean values of RBC and platelet of EIC were significantly decreased by age (p<0.05). The mean values of RBC, HCT, MCV and MCHC between EIC and KIC of the same age (2~3 years) showed the statistical significance (p<0.05). Also, in the WBC of EIC, the mean values were decreased according to the age from $13.9{\times}10^3/{\mu}L{\sim}12.7{\times}10^3/{\mu}L$ under 1 year to $9.1{\times}10^3/{\mu}L{\sim}11.5{\times}10^3/{\mu}L$ over 2 years respectively. In the differential count of WBC of EIC (White, Black, Mini cattle), it showed generally the rates of 40.2%, 52.2%, 49.0% lymphocyte and 27.2%, 33.9%, 32.0% segmented neutrophil from 2~3 years respectively. Result of this study will be used for establishing reference range for blood analysis in EIC such as white, black and mini cattle. This study reported hematological values which could serve as baseline information for comparison in conditions of nutrient deficiency, physiological and health status of endangered Korean native cattle. In addition, this study provides a valuable resource for further investigations of the preservation of rare genetic stocks underlying traits of interest in cattle.

• Journal of the Korean Applied Science and Technology
• /
• v.33 no.4
• /
• pp.647-657
• /
• 2016

In this study, the antioxidative effects and active component analysis of 50% ethanol extract, ethyl acetate fraction and aglycone fraction obtained from Prunella vulgaris L. were investigated. The free radical scavenging activities ($FSC_{50}$) was investigated at 50% ethanol extract ($15.25{\mu}g/mL$), ethyl acetate fraction ($8.68{\mu}g/mL$), and aglycone fraction ($8.25{\mu}g/mL$) respectively. Reactive oxygen species (ROS) scavenging activities ($OSC_{50}$) in $Fe^{3+}-EDTA/H_2O_2$ system using the luminol-dependent chemiluminescence assay was investigated at 50% ethanol extract ($4.68{\mu}g/mL$), ethyl acetate fraction ($1.00{\mu}g/mL$), and aglycone fraction($1.02{\mu}g/mL$) respectively. In the cellular protective effect against $^1O_2$ induced cellular damage of human erythrocytes, extract/fractions of P. vulgaris L. were increased in a concentration dependent manner($1{\sim}25{\mu}g/mL$). Especially, ${\tau}_{50}$ of aglycone fraction at concentrations of $25{\mu}g/mL$ showed the most protective effects at 337.9 min. It's showed nine times higher (+)-${\alpha}$-tocopherol (${\tau}_{50}=38.7min$) as typical antioxidant in the $^1O_2$-induced photohemolysis of human erythrocytes. TLC and HPLC were used to analyse active components in the ethyl acetate fraction and aglycone fraction of P. vulgaris L. In ethyl acetate fraction, caffeic acid, rosmarinic acid, quercetin 3-${\beta}$-D-glucoside, rutin, kaempferol-3-O-rutinoside, astragalin (kaempferol-3-O-glucoside) were identified. In aglycone fraction, caffeic acid, rosmarinic acid, quercetin, kaempferol were identified. These results indicated that extract/fraction of P. vulgaris L. is may be used in cosmetics industry as natural antioxidants by quenching and/or scavenging $^1O_2$ and other ROS, and protecting cellular membranes.

• 한국생물공학회:학술대회논문집
• /
• 2005.04a
• /
• pp.152-156
• /
• 2005

In this study, we tried to optimize the composition of medium and culture conditions for the total avermectin and avermectin B1 production from S. avermitilis, which is a natural producer of avermectin family. Among various carbon and organic nitrogen sources tested, fructose and malt extract were most effective on avermectin production. Next addition of polyethylene glycol and $K_{2}HPO_{4}$ in medium significantly improved the intracellular contents of avermectin. Thus the optimized medium composition was 50 g/L fructose, 30 g/L malt extract, 5 g/L casamino acid, 2.5 g/L PEG 3,350, and 1 g/L $K_{2}HPO_{4}$, which increased the avermection production from10 to 478 mg/L. The contents of avermectin B1 complex was about 50% of the total amount of avermectin.

• Journal of Environmental Health Sciences
• /
• v.24 no.3
• /
• pp.131-136
• /
• 1998

Attached algal community and several physico-chemicai characters were investigated at Seokjong hot spring in Chollabukdo in February and in April, 1997. The results of physico-chemicai factors are as follows : water temperatures were varied from 6.5$^{\circ}$C to 32.0$^{\circ}$C; pH range was 6.9 to 7.7; The levels of electric conductivity were 105 $\mu$mhos/cm to 477 $\mu$mhos/cm; chemical oxygen demand(COD) range was 1.5 mg/l to 21.2 mg/l; ammonia concentration was 0.20 mg/l to 8.74 mg/l; nitrate concentrations were 0.36 mg/l to 2.43 mg/l; phosphate concentration was N.D. to 0.52 mg/l; sulfur concentration was 14.6 mg/l to 66.1 mg/l. Attacched algal species were identified. Totally, 63 taxa were classified and composed of 4 phylum, 4 class, 10 order, 17 family and 31 genera. The total biomass of attacched algae was $1.036 \times 10^{7}$ cells/l that composed of $5.39 \times 10^{6}$ cells/l of blue-green algae, $4.05 \times 10^{6}$ cells/l of diatom and $0.93 \times 10^{6}$ cells/l of green algae. The succession of dominant species was Synechocystis thermalis. This could be due to the thermal wastewaters. in biotic indices tests, the values of dominance index(DI) were 0.33 to 0.67 in winter, 0.18 to 0.68 in spring. The values of diversity index(H') were 1.44 to 2.69 in winter, 1.62 to 2.89 in spring. And the values of eveness index (J) were 0.31 to 0.61 in winter, 0.37 to 0.65 in spring.

• Journal of Microbiology and Biotechnology
• /
• v.25 no.3
• /
• pp.358-365
• /
• 2015

ε-Poly-L-lysine (ε-PL) is a homopolymer of L-lysine molecules connected between the epsilon amino and alpha carboxyl groups. This polymer is currently used as a natural preservative in food. Insufficient biomass is a major problem in ε-PL fermentation. Here, to improve cell growth and ε-PL productivity, various nitrogen-rich nutrients were supplemented into flask cultures after 16 h cultivation, marking the onset of ε-PL biosynthesis. Yeast extract, soybean powder, corn powder, and beef extract significantly improved cell growth. In terms of ε-PL productivity, yeast extract at 0.5% (w/v) gave the maximum yield (2.24 g/l), 115.4% higher than the control (1.04 g/l), followed by soybean powder (1.86 g/l) at 1% (w/v) and corn powder (1.72 g/l) at 1% (w/v). However, supplementation with beef extract inhibited ε-PL production. The optimal time for supplementation for all nutrients examined was at 16 h cultivation. The kinetics of yeast-extract-supplemented cultures showed enhanced cell growth and production duration. Thus, the most commonly used two-stage pH control fed-batch fermentation method was modified by omitting the pH 5.0-controlled period, and coupling the procedure with nutrient feeding in the pH 3.9-controlled phase. Using this process, by continuously feeding 0.5 g/h of yeast extract, soybean powder, or corn powder into cultures in a 30 L fermenter, the final ε-PL titer reached 28.2 g/l, 23.7 g/l, and 21.4 g/l, respectively, 91.8%, 61.2%, and 45.6% higher than that of the control (14.7 g/l). This describes a promising option for the mass production of ε-PL.

• Phonetics and Speech Sciences
• /
• v.11 no.4
• /
• pp.81-87
• /
• 2019

The purpose of the current study is to investigate the realization of speech rhythm in English as spoken by Korean learners of English. The study particularly aims to examine the rhythm metrics of English read speech by learners who speak Busan or the South Kyungsang dialect of Korean. Twenty-four learners whose L1 is Busan Korean and eight native speakers of English read a passage wherein five sentences were segmented and labeled as vocalic and intervocalic intervals. Various rhythm metrics such as %V, Varcos, and Pairwise Variability Indexes (PVIs) were calculated. The results show that Korean learners read English sentences with significantly more vocalic and consonantal intervals at a slower speech rate than native English speakers. The analyses of rhythm metrics revealed that when the speech rate was not normalized, Korean learners' English showed more variability in the length of consonantal and vocalic intervals. However, speech-rate-normalized rhythm metrics for vocalic intervals indicated that Korean learners transferred their L1 rhythmic structures (a syllable-timed language) into their L2 speech (a stress-timed language). Overall, the results suggest that Korean learners' English reflects the rhythmic characteristics of their L1. The effect of the learners' L1 dialect on the realization of L2 speech rhythm is also speculated.

• Korean Journal of Environmental Biology
• /
• v.32 no.1
• /
• pp.16-25
• /
• 2014

To identify distribution of epilithic diatom assemblages and the relationship between diatoms and water chemistry, samples were collected twice a year from 2008 to 2012, from at 6 streams in Jeju Island, South Korea. A total of 171 diatom taxa were identified, and Achnanthes lanceolata, Gomphonema pumilum, Melosira varians, Navicula minima and Nitzschia palea were dominantly observed. BOD ranged 0.0~1.6 mg $L^{-1}$, TN 0.230~13.240 mg $L^{-1}$ (average 4.432 mg $L^{-1}$), TP 0.020~0.316 mg $L^{-1}$ (average 0.092 mg $L^{-1}$), and N/P rate ranged 2.5~178.5. Average of epilithic algal chlorophyll-a and AFDM were 1.1 ${\mu}gcm^{-2}$ and 0.6 mg $cm^{-2}$, respectively. According to BOD standard, the water qualities of study area sites were at 'Good' level. However, the healthiness levels assessed from DAIpo and TDI were 'Fair' to 'Poor'.

• Animal Systematics, Evolution and Diversity
• /
• v.7 no.1
• /
• pp.65-72
• /
• 1991

The interspecific relationships of the genus Leucophenga, L.concilia, L.maculata, L.orientalis , and L.quinquenmaculipennis were investigated by soluble proteins analysis. the electrophoretic banding patterns of the four species analyzed by SDS-PAGE were scanned by densitormeter. The soluble protein patters of L.maculata and L.concilia by SDS-PAGE appeared similarly and on the other hand, those of L.quinquemaculipennis had a different forms from three other species. The genetic distance among the four species of TDE analysis was calculated by formula of the Aquadro and Avis(1981) . The genetic distance between L.maculata and L.concilia was 0.393 , the lowest of all and between L.maculata and L.quinquemaculipennis was 0.496, the highest of all. The dendrogram was established using UPGMA method based on genetic distance obtained by TDE analysis. Clustered patterns as follows ; first, L.maculata and L.concilia were clustered, and L.orientalis and L. quinquemaculipennis followed the firstone in order. In consequence, it seems that the interspecific relationship of L.quinquemaculipennis was farther from the other three species, while that of L.maculata and L.concilia was closer than that of L.orientalis.

• Microbiology and Biotechnology Letters
• /
• v.27 no.4
• /
• pp.327-332
• /
• 1999

A highly productive fed-batch fermentation process was developed for the production of L-ornithine by using a new stabilized strain, Breviabcterium ketoglutamicum BK52. Fed-batch cultures with a continuous feeding of the complex medium were conducted on various operating conditions. The optimal concentration of phosphate in the complex medium was 2.1g/L. The optimal feeding rate of L-arginine was 0.028g/L/hr. The optimal feeding point of the complex medium was determined to be at 40 OD of the cell mass. The final L-ornithine concentrations within 64hrs of cultivation in 5 and 50 liter fermenters were 73g/L and 71g/L, respectively. The maximum overall L-ornithine productivity was 1.14g/L/hr which was about 2 times higher than that of the conventional fed-batch culture with intermittent feeding. The overall productivity of the fermentation system is remarkably improved by employing the optimized conditions, and it offers a significant potential for industrial application.