• Journal of Radiation Protection and Research
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• 제11권1호
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• pp.44-50
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• 1986

천연우라늄의 생체내 흡수 및 분포의 역학적 정보와 반응을 알기 위하여 질산우라늄을 투여하여 변동되는 조직분포 및 혈중 BUN, Creatinine, SGPT 및 SGOT의 활성도를 측정하였다. 조직중의 우라늄 함량은 방사화분석법을 이용하여 방출되는 ${\gamma}$ 에너지의 강도를 측정함으로써 조사 하였다. 이때 시간이 경과함에 따른 질산우라늄의 조직분포의 양상은 특히 폐가 다른 장기에 비하여 현저하게 축적되는 것을 관찰하였다. 한편 25 mg/kg의 질산우라늄 투여시 비효소계인 질소대사의 임상적 지표인 BUN 및 Creatinine값은 예민한 반응을 나타냈으나 효소계의 SGPT 및 SGOT의 활성도에는 큰 변화가 없었다. 1 mg/kg의 질산우라늄 투여에 의한 SGPT 및 SGOT의 활성도의 변화는 복강투여후 90분에 최고치를 나타내다가 회복되었다. 우라늄 흡수의 조직분포의 실험결과 간장 및 신장의 축적이 흡수초기에 최고치를 나타내다 다시 감소되는 결과로 미루어 보아 우라늄의 독성을 가장 크게 나타나는 결정장기(critical organ)는 신장이나 간장이 아니고 폐장임을 알 수 있었다.

• 식물조직배양학회지
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• 제22권3호
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• pp.143-148
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• 1995

벼의 뿌리조직을 기내배양하여 배발생캘러스의 형성과 식물체 재분화율의 품종간 차이 및 완숙배와 뿌리조직에서 유래된 캘러스의 현탁배양 기간별 부정배 형성정도와 식물체 재분화율 등에 대한 몇가지 실험을 수행하여 얻어진 결과를 요약하면 다음과 같다. 벼 뿌리조직으로부터 캘러스 형성 및 식물체 재분화 능력의 품종간 차이는 뚜렷하게 나타났으며, 자포니카형 품종들이 통일형 품종에 비해 캘러스의 생장량도 많고 식물체 재분화율도 높은 경향이었고, 공시품종 중 "영덕벼"의 식물체 재분화율이 13%로 가장 높았다. 뿌리 및 현미배양에서 형성된 캘러스를 고체배지에서 2 주 간격으로 7회 계대배양한 바, 계대배양 횟수가 증가됨에 따라 식물체 재분화율이 증가되었다가 5회째부터는 점차 감소하였다. 뿌리조직에서 형성된 캘러스의 현탁배양에서 모양이 둥근세포와 그들의 세포괴는 배양 24일 후에 최대치를 나타내었고 그 이후는 감소하였다. 현탁배양 기간별 뿌리조직에서 형성된 캘러스의 체세포배 형성률은 배양 90일까지는 배양기간이 길어질 수록 증가하였으나, 그 이후는 감소하였고, 식물체 재분화율도 배양기간이 길어질수록 감소하는 경향이었다.소하는 경향이었다.

• 미생물학회지
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• 제17권4호
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• pp.187-192
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• 1979

Dennis (1972) reported that Trichosporon cutaneum FRI-425 from the petioles of Pheum rhamponticum var, had showed the celluloytic activity. Chun (1977) also suggested that Trichoporon pullulons 225 isolated from the saline water of the Yeoung San River had a similar properties. However, the assay conditions for enzyme activity were not yet investigated. Thus, the present work was undertaken to examine some conditions for CMCase activity and at the same time to compare the activities of crude enzyme produce from above two species of Trichosporon pullulans. The results are as follows; 1. The maximum production of total reducing sugar by crude enzyme of Tr. pululans was after 30 minutes, whereas that of Tr. cutanuem FRI-425 was after 90 minutes. This fact showed that the reaction velocity of enzyme from Tr. pullulans 225 was more faster than that of Tr. cutaneum FRI-425. 2. Two species showed a similar trend to increase the production of reducing sugar in proportion to the increment in substrate concentration and to arrive at maximum level at lmg/ml of substrate concentration. However, Tr. pullulans 225 produced more $50{\mu}g$ of reducing sugar compared to Tr. cutaneum. 3. The optimum PH for CMCase activity is 5.0 for Tr. pullulans 225 as well as Tr. cutaneum FRI-425, and PH stability lie within the range of 6 and 8. In the activity and stability of enzyme on PH changes, enzyme of Tr. cutaneum FRI-425 was more unstable than that of TY. pullulans 225. 4. The optimum temperature for CMCase activity was $40^{\circ}C$, and enzyme activity from Tr. pullulans 225 was more sensitive to temperature changes compared with that of TY. cutaneum. The heat stability was within $40^{\circ}C$, but that was rapidly decreased above $40^{\circ}C$. In comparison of the heat stability for enzyme of Tr. cutaneum FRI-425 with that of Tr. pullulans 225 at the same temperature of $80^{\circ}C$, the former was some 10 percent more stable than the latter.

• The Plant Pathology Journal
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• 제31권1호
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• pp.25-32
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• 2015

Pseudomonas coronafaciens causes halo blight on oats and is a plant quarantine bacterium in many countries, including the Republic of Korea. Using of the certificated seed is important for control of the disease. Since effective detection method of P. coronafaciens is not available yet, PCR and TaqMan PCR assays for specific detection of P. coronafaciens were developed in this study. PCR primers were designed from the draft genome sequence of P. coronafaciens LMG 5060 which was obtained by the next-generation sequencing in this study. The PCR primer set Pc-12-F/Pc-12-R specifically amplified 498 bp from the 13 strains of P. coronafaciens isolated in the seven different countries (Canada, Japan, United Kingdom, Zimbabwe, Kenya, Germany, and New Zealand) and the nested primer set Pc-12-ne-F/Pc-12-ne-R specifically amplified 298 bp from those strains. The target-size PCR product was not amplified from the non-target bacteria with the PCR and nested primer sets. TaqMan PCR with Pc-12-ne-F/Pc-12-ne-R and a TaqMan probe, Pc-taqman, which were designed inside of the nested PCR amplicon, generated Ct values which in a dose-dependent manner to the amount of the target DNA and the Ct values of all the P. coronafaciens strains were above the threshold Ct value for positive detection. The TaqMan PCR generated positive Ct values from the seed extracts of the artificially inoculated oat seeds above 10 cfu/ml inoculation level. PCR and TaqMan PCR assays developed in this study will be useful tools to detect and identify the plant quarantine pathogen, P. coronafaciens.

• 한국작물학회지
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• 제29권4호
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• pp.401-408
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• 1984

우리나라에서 고구마 장려품종인 홍미와 신미를 액아배양시 explant의 크기 NAA, BA 및 kinetin의 농도가 기관분화와 생육에 미치는 영향을 구명하고저 본 실험을 실시하였으며 실험결과를 요약하면 다음과 같다. 1. 5mm되는 explant 배양이 2mm explant 배양보다 기관분화 및 생육이 좋았으며 홍미는 MS 배양에 NAA 0.1mg/$\ell$와 kinetin 1mg/$\ell$을 조합처리할 때 신미는 MS배지에 NAA 0.1mg/$\ell$와 kinetin 1mg/$\ell$을 조합처리할 때와 kinetin 1mg/$\ell$, BA 0.1mg/$\ell$을 단독처리할 때 shoot의 분화가 좋았다. 2. 뿌리분화는 홍미와 신미가 비슷한 결과를 보였으며 NAA 0.lmg/$\ell$와 kinetin 1mg/$\ell$을 조합처이한 배지에서 뿌리수와 뿌리길이가 증가하였다. 3. BA의 농도가 증가함에 따라 비정상 식물체의 출현이 많았으며 한 개의 explant에서 여러개의 shoot의 길이가 짧았다. 4. 이차계대배양에서 shoot의 분화 및 생장은 NAA 0.1mg/$\ell$와 kinetin 1mg/$\ell$가 첨가된 배지에서 좋은 결과를 보였고 뿌리의 분화는 0.1 mg/$\ell$ BA에 첨가된 배지에서 가장 효과적이었다.

• Journal of Microbiology and Biotechnology
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• 제22권3호
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• pp.311-315
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• 2012

A novel ${\beta}$-proteobacterium, designated BXN5-$27^T$, was isolated from soil of a ginseng field of Baekdu Mountain in China, and was characterized using a polyphasic approach. The strain was Gram-staining-negative, aerobic, motile, non-spore-forming, and rod shaped. Strain BXN5-$27^T$ exhibited ${\beta}$-glucosidase activity that was responsible for its ability to transform ginsenoside $Rb_1$ (one of the dominant active components of ginseng) to compound Rd. Phylogenetic analysis based on 16S rRNA gene sequences showed that this strain belonged to the family Comamonadaceae; it was most closely related to Ramlibacter henchirensis $TMB834^T$ and Ramlibacter tataouinensis$TTB310^T$ (96.4% and 96.3% similarity, respectively). The G+C content of the genomic DNA was 68.1%. The major menaquinone was Q-8. The major fatty acids were $C_{16:0}$, summed feature 4 (comprising $C_{16:1}$ ${\omega}7c$ and/or iso-$C_{15:0}$ 2OH), and $C_{17:0}$ cyclo. Genomic and chemotaxonomic data supported the affiliation of strain BXN5-$27^T$ to the genus Ramlibacter. However, physiological and biochemical tests differentiated it phenotypically from the other established species of Ramlibacter. Therefore, the isolate represents a novel species, for which the name Ramlibacter ginsenosidimutans sp. nov. is proposed, with the type strain being BXN5-$27^T$ (=DSM $23480^T$ = LMG $24525^T$ = KCTC $22276^T$).

• Journal of Microbiology and Biotechnology
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• 제20권10호
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• pp.1386-1392
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• 2010

A bacterial strain designated GR5$^T$, previously isolated from a freshwater culture pond in Taiwan while screening for bacteria for antimicrobial compounds, was characterized using a polyphasic taxonomic approach. Strain GR5$^T$ was found to be Gram-negative, aerobic, greenish-yellow colored, rod-shaped, and motile by means of a single polar flagellum. Growth occurred at $10-40^{\circ}C$ (optimum, $35^{\circ}C$), pH 7.0-8.0 (optimum pH 8.0), and with 0-2.0% NaCl (optimum, 0.5-1.0%). The major fatty acids were $C_{16:1}{\omega}7c$(36.3%), $C_{16:0}$(16.6%), $C_{12:0}$ 3-OH (12.5%), and $C_{18:1}{\omega}7c$(9.1%). The major respiratory quinone was Q-8, and the DNA G+C content of the genomic DNA was 51.9 mol%. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain GR5$^T$ belongs to the genus Rheinheimera, where its most closely related neighbors are Rheinheimera texasensis A62-14B$^T$ and Rheinheimera tangshanensis JA3-B52$^T$ with sequence similarities of 98.1% and 97.5%, respectively, and the sequence similarities to any other recognized species within Gammaproteobacteria are less than 96.5%. The mean level of DNA-DNA relatedness between strain GR5$^T$ and R. texasensis A62-14B$^T$, the strain most closely related to the isolate, was $26.5{\pm}7.6%$. Therefore, based on the phylogenetic and phenotypic data, strain GR5$^T$ should be classified as a novel species, for which the name Rheinheimera aquatica sp. nov. is proposed. The type strain is GR5$^T$ (=BCRC 80081$^T$=LMG 25379$^T$).

• 대한화학회지
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• 제5권1호
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• pp.42-47
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• 1961

A titration of a small amount of iron with standard potassium ferrocyanide using potassium thiocyanate as indicator has been studied. A sample solution containing $0.1{\sim}1.0$ mg. $Fe^{3+}$ in 60 ml. is pipeted into 100 ml. Erlenmyer flask and the pH of the solution is adjusted to $1.5{\sim}3.0$ with 0.1 N or 1 N $HNO_3$ and $NH_4OH.$ To this solution one ml. of 1 M KCNS solution as indicator is added. The solution colored by iron thiocyanate complex is titrated with 1/200 M or 1/400 M standard solution of potassium ferrocyanide from a 5 ml. micro-buret. Near the end point, when the color of sample changes from deep red to green, about 20 ml. of ether is added and shake the flask vigorously. The red color is extracted to the ether layer. To settle the ether layer a few drops of ethanol is added and then standard solution is added dropwise and shake vigorously. The end point is reached when the color of the ether layer disappears owing to the quantitative formation of $Fe_4[Fe(CN)_6]_3.$ In this titration, 0.lmg. of $Fe^{3+}$ can be determined within 1.0% of titration error, provided the following optimum conditions, i.e., pH $1.5{\sim}3.0$, final concentration of KCNS indicator; $0.01{\sim}0.02M$, at room temperature. The titration found to be interfered by the presence of slightly soluble salts, stable complex forming ions and the ions which would be reduced by ferrocyanide or oxidized by ferric ion.

• Journal of Microbiology and Biotechnology
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• 제22권12호
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• pp.1621-1628
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• 2012

The agar-degrading bacterium GNUM-1 was isolated from the brown algal species Sargassum serratifolium, which was obtained from the West Sea of Korea, by using the selective artificial seawater agar plate. The cells were Gram-negative, $0.5-0.6{\mu}m$ wide and $2.0-2.5{\mu}m$ long curved rods with a single polar flagellum, forming nonpigmented, circular, smooth colonies. Cells grew at $20^{\circ}C-37^{\circ}C$, between pH 5.0 and 9.0, and at 1-10% (w/v) NaCl. The DNA G+C content of the GNUM-1 strain was 45.5 mol%. The 16S rRNA sequence of the GNUM-1 was very similar to those of Alteromonas stellipolaris LMG 21861 (99.86% sequence homology) and Alteromonas addita $R10SW13^T$(99.64% sequence homology), which led us to assign it to the genus Alteromonas. It showed positive activities for agarase, amylase, gelatinase, alkaline phosphatase, esterase (C8), lipase (C14), leucine arylamidase, valine arylamidase, ${\alpha}$-chymotrypsin, acid phosphatase, naphthol-AS-BI-phosphohydrolase, ${\alpha}$-galactosidase, ${\beta}$-galactosidase, ${\beta}$-glucosidase, catalase, and urease. It can utilize citrate, malic acid, and trisodium citrate. The major fatty acids were summed feature 3 (21.5%, comprising $C_{16:1}{\omega}7c/iso-C_{15:0}$ 2-OH) and C16:0 (15.04%). On the basis of the variations in many biochemical characteristics, GNUM-1 was considered as unique and thus was named Alteromonas sp. GNUM-1. It produced the highest agarase activity in modified ASW medium containing 0.4% sucrose, but lower activity in rich media despite superior growth, implying that agarase production is tightly regulated and repressed in a rich nutrient condition. The 30 kDa protein with agarase activity was identified by zymography, and this report serves as the very first account of such a protein in the genus Alteromonas.

• 아시안잔디학회지
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• 제11권4호
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• pp.311-320
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• 1997

This study was carried out to induce and maintain callus from 59 zoysiagrass lines, to know the effective disinfestation method for zoysiagrass stolon as explant and the difference in the response of callus induction among 59 lines, and to investigate the effect of medium, growth regulators, light, temperature, stolon part and internode position on callus induction and emhryogenic callus(E.C.) formation. The treatment of 0.lmg/L $HgCl_2$for 15 min resulted in no contamination and the highest callus induction(46.6%). Callus was induced from the 59 zoysiagrass lines. The callus growth of Z. japonica and Z. sinica was generally better than Z. matrella Ten cell lines whose callus and stolon grow fast in culture and in field, respectively were selected to he used for breeding. Callus induction was the most effective at 2.0mg /L of both 2, 4-D and picloram in MS medium. MS medium was the best for callus induction and growth while LS medium was the best for embryogenic callus and shoot formation. Callus induction and growth was better at 28, 31$^{\circ}C$. than 25$^{\circ}C$. and dark condition was better than light condition in MS me-dium containing 2mg/L 2,4-D. While callus induction was better with node part as explant than with internode part, callus growth and embryogenic callus formation was better with internode part. In 'Japonica 1', the first internode was the most effective in callus induction, but third internode was the best in '$M_2$ X $S_2$'.