• Journal of Plant Biology
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• 제35권3호
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• pp.229-235
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• 1992

담배 식물체에서 Arabidopsis thaliana에 존재하는 3가지 다른 엽록소 a/b 결합 단백질 (cab) 유전자 promoter들의 발현을 조사하였다. 이들 promoter의 활성은 이들 promoter에 결합된 reporter gene의 식물인 CAT (chloramphenicol acetyltransfer-ase)의 활성으로 측정하였다. 담배엽에서 cab promoter의 활성은 cab1, cab2, cab3의 순이었고, 이들 잎에서 유도한 callus나 shoot에서도 동일한 양상을 보였다. 이들 3가지 promoter의 발현은 상부엽에서 하부엽보다 높은 활성은 보였으며 개체간의 높은 변이폭은 뿌리내리기를 통하여 무성증식된 식물체를 사용하여 줄일 수 있었다. 이들은 또한 기관 특이성을 보여 줄기 보다 잎에서의 활성이 높았고 뿌리에서는 거의 발현되지 않았다. 그러나 cab1 promoter의 경우, 다른 두 cab promoter들과는 다르게, 잎에 대한 줄기에서의 상대적인 활성이 높았으며, CAT 활성을 단위 단백질당을 표시하는 대신 단위 엽록소당 활성으로 나타내었을 때 줄기와 잎에서 활성의 차이가 관찰되지 않았다. 즉 cab2와 cab3는 광합성 기관 특이성을 보이는 반면 cab1의 경우는 이러한 특이성을 나타내지 않았다. 이러한 현상은 잎에서 유도한 shoot가 줄기와 잎으로 분화되는 과정에서도 관찰되었다.

• 한국수산과학회지
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• 제35권4호
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• pp.327-335
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• 2002

Effects of available food on growth of commercially cultured Pacific oysters, Crassostrea gigas in Goseong Bay on the south coast were studied using a numerical model. levels of total protein, carbohydrate and lipid in particulate organic matter in the water column as well as chlorophyll a concentration were determined for estimating total available food for oyster growth. Environmental parameters including water temperature, salinity and total suspended solid were also monitored for the model. Oyster growth was also monitored by means of measuring shell length and tissue wet weight increase on a monthly basis. Simulation results from the numerical model indicated that chlorophyll a is not a good representative of available food for the oysters in Goseong Bay. In contrast, available food in the water column measured by filtration of the organic particles and analyzed in terms of total lipids, carbohydrates and protein was well matched with simulated oyster growth in the Bay which is similar to observed growth. The model also suggested that oysters have relatively low retention efficiency of $50\%$ or less. This result indicates that oysters in the bay utilize only a part of food particle available in the water column, as reported in other studies.

• Plant Resources
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• 제8권3호
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• pp.202-208
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• 2005

Osmotic stress is one of major limiting factors in crop production. In particular, seasonal drought often causes the secondary disease in the field, resulting in severe reduction in both quality and productivity. Recent efforts have revealed that many genes encoding protein kinases play important roles in osmotic stress signal transduction pathways. Previously, the AtSIK (Arabidopsis thaliana Stress Inducible Kinase) mutants have shown to enhance tolerance to abiotic stresses, accompanying with higher expression of abiotic stress-related genes than did the wild-type plants. In this study, we have transformed potato (cv. Taedong Valley) with the AtSIK expression cassette. Both PCR and RT-PCR using AtSIK-specific primers showed stable integration and expression of the AtSIK gene in individual transgenic lines, respectively. Foliar application of herbicide ($Basta^{(R)}$) at commercial application rate (0.3% (v/v)) revealed another evidence of stable gene introduction of T-DNA which includes the bar gene for herbicide resistance. Overexpression of the AtSIK gene under dual CaMV35S promoter increased sensitivity to salt stress (300 mM NaCl), which was demonstrated by the reduction rate of chlorophyll contents in leaves of transgenic potato lines. These results suggest that possible increase of osmotic tolerance in potato plants may be achieved by antisense expression of AtSIK gene.

• 한국식품과학회지
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• 제40권3호
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• pp.303-310
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• 2008

아보카도 오일의 산업적인 이용성을 증가시키고, 안정성을 향상시키기 위해 분무건조기술을 이용하여 아보카도 오일의 캡슐화 연구를 수행하였다. 캡슐화된 샘플내의 오일과 오일자체만을 4, 25, $60^{\circ}C$ 온도의 암조건에서 8주 동안 저장하여 TBA값을 측정한 결과, 캡슐 속의 오일이 대조군과 비교하였을 때 산화에 더 안정하였다. 대조군의 TBA 형성은 저장기간이 길어질수록 증가하고 5주째에 급격하게 증가하였다. 그러나 캡슐화된 샘플 내에서의 TBA 값은 대조군보다 낮은 값을 나타내었다. 캡슐화된 샘플의 TBA 값은 아보카도 오일내의 MDA형성을 저지시켜 산화작용을 효과적으로 억제하였다. 분무 건조된 분말의 가운데서는 단백질의 함량이 커질수록 그 안정성이 감소하는 경향을 나타내었다. 클로로필 안정성을 60oC의 저장조건에서 비교한 결과 캡슐화된 시료 내에서 안정성을 보여주었다. 저장된 샘플 내 오일의 색도를 측정한 결과, 통계적인 유의성을 관찰할 수는 없었으나, 전체적으로 L값은 감소하고 a값은 증가하며, b값은 감소하는 경향을 나타내었다. 결론적으로 TBA 값 및 클로로필 함량, 색도의 실험결과에 의하면 아보카도 오일의 캡슐화가 산화를 억제하고 관능적인 특성을 향상시키는데 효과적인 수단임을 나타낸다.아보카도 오일의 산업적인 이용성을 증가시키고, 안정성을 향상시키기 위해 분무건조기술을 이용하여 아보카도 오일의 캡슐화 연구를 수행하였다. 캡슐화된 샘플내의 오일과 오일자체만을 4, 25, 60oC 온도의 암조건에서 8주 동안 저장하여 TBA값을 측정한 결과, 캡슐 속의 오일이 대조군과 비교하였을 때 산화에 더 안정하였다. 대조군의 TBA 형성은 저장기간이 길어질수록 증가하고 5주째에 급격하게 증가하였다. 그러나 캡슐화된 샘플 내에서의 TBA 값은 대조군보다 낮은 값을 나타내었다. 캡슐화된 샘플의 TBA 값은 아보카도 오일내의 MDA형성을 저지시켜 산화작용을 효과적으로 억제하였다. 분무 건조된 분말의 가운데서는 단백질의 함량이 커질수록 그 안정성이 감소하는 경향을 나타내었다. 클로로필 안정성을 $60^{\circ}C$의 저장조건에서 비교한 결과 캡슐화된 시료 내에서 안정성을 보여주었다. 저장된 샘플 내 오일의 색도를 측정한 결과, 통계적인 유의성을 관찰할 수는 없었으나, 전체적으로 L값은 감소하고 a값은 증가하며, b값은 감소하는 경향을 나타내었다. 결론적으로 TBA 값 및 클로로필 함량, 색도의 실험결과에 의하면 아보카도 오일의 캡슐화가 산화를 억제하고 관능적인 특성을 향상시키는데 효과적인 수단임을 나타낸다.

• 한국작물학회지
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• 제67권2호
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• pp.77-84
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• 2022

일품등 9품종을 대상으로 경북 남부 평야지역 봄 가뭄 대응 벼 품종별 재배안정성을 평가하기 위해 분얼초기 인위적으로 수분 부족 스트레스를 유도한 결과는 다음과 같다. 1. 일품등 9품종 대상으로 수분 부족 스트레스에 따른 결과는 평균적으로 관행대비 출수기는 약10일 빠르고 쌀수량은 약 18.6% 감소, 담백질 함량은 20.2% 증가, 식미치는 8.3% 감소하였다. 2. 본 연구에서 수량에 가장 영향을 미치는 인자는 2차 지경 분화기에 가장 영향을 받는 영화수와 천립중으로 나타났다. 3. 잎마름이 50%에 도달할때까지 소요일수가 가장 긴 품종은 새누리, 가장 짧은 품종은 대보였다. 4. 재관개 후에도 대보와 삼광은 수량감소가 가장 컸을뿐 아니라 F_V/F_M 관행 초기값으로 회복하지 못하여 가뭄의 광생리학적 지표의 가능성을 확인하였다. 따라서 경북 남부 평야지역에서는 봄 가뭄 대응 내건성 벼 품종은 새누리와 하이아미가 가장 적합하고 내건성이 약한 품종들은 재관개 후에도 광합성 효율이 낮아 수량감소로 이어져 이러한 결과에 따라 관행대비 쌀 수량감소율과 단백질 함량이 낮고 식미치가 높은 품종으로 새누리, 하이아미가 내건성 적합품종으로 선발되었다.

• 생명과학회지
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• 제16권3호
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• pp.510-515
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• 2006

담배에서 기내 생장, 엽록소 및 광합성 효소인 rubisco와 rubisco activase에 미치는 벤질 아데닌(BA)의 영향을 연구하였다. 여러 농도의 BA 처리 후 11주에 2 ${\mu}M$의 농도에서 기내 생장과 엽록소의 함량이 가장 현저하였다. Rubisco의 함량은 BA의 농도가 증가함에 따라 같이 증가하여 2 ${\mu}M$에서 가장 높았으나, 이후 농도의 증가에 따라 감소함으로서 억제 현상을 보였다. Rubisco의 활성 또한 함량과 같은 현상을 나타냈다. 이 결과들은 rubisco의 활성이 함량과 연관되어 있음을 의미한다. Rubisco에 대한 이러한 효과가 rubisco activase와 관련되어 있을 것이라는 가정하에 이 효소의 함량과 활성을 측정한 결과, 2 ${\mu}M$ BA에서 가장 증가하였다. 이러한 결과들을 종합하면 BA에 의한 rubisco의 활성화 효과는 rubisco activase와 관련되어 있음을 보여준다.

• Journal of Photoscience
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• 제7권2호
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• pp.39-44
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• 2000

To examine the chilling tolerance lipids, we compared the chilling susceptibility of photosystem II of wild type tobacco plants with that of transgenic tobacco plants, in which the sensitivity to chilling had been enhanced by genetic modification of fatty acid unsaturation of chloroplast membrane lipids. The transgenic tobacco plants were found to contain reduced levels of unsaturated membrane fatty acids by being tansformed with cDNA for glycerol-3-phosphate acyltransferase from squash. For the purpose of studying on the functional integrity of photosystem II during low-temperature photoinhibition, the photochemical efficiency was measured as the ration of the maximun fluorescence of chlorophyll (Fv/Fm) of photosystem II. In parallel with an investigation on the transgenic plants, susceptibility of chilling-resistant species, such as spinah and pea, and of chilling-sensitive ones, such as squash and sweet potato, to low-temperature photoinhibition was also compared in terms of room temperature-induced chlorophyll fluorescence from photosystem II. When leaf disks from the two genotypes of tobacco plants were exposed to light at 5$^{\circ}C$, the transgenic plants showed more rapid decline in photochemical activity of photosysytme II than wild-type plants. When they were pretreated with lincomycin, an inhibitor of chloroplast-encoded protein synthesis, the extent of photoinhibition was even more accelerated. More impottantly, they showed a comparable extent of photoinhibition in the presence of lincomycin, making a clear contrast to the discrepancy observed in the discrepancy observed in the absence of lincomycin. Restoration of Fv/Fm during recovery from low-temperature photoinhibition occurred more slowly in the transgenic tobacco plants than the wild-type. These findings are discussed in relation to fatty acid unsaturation of membrane phosphatidylglycerol. It appears that the ability of plants to rapidly regenerate the active photosystem II complex from might explain, in part, why chilling-resistant plants can toleratlow-temperature photoinhibition.

• 한국수산과학회지
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• 제42권6호
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• pp.555-560
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• 2009

To identify the food characteristics of seven melania snail species in Korea, the detailed proximate, fatty/amino acid, mineral composition and chlorophyll contents were investigated. The content ranges of moisture, crude protein, crude lipid and ash were 70.1-81.0%, 11.6-16.9%, 0.4-1.6% and 1.9-3.4%, respectively. K. nadifila showed the significant mineral contents Fe, P, Ca than other species. Total Chlorophyll level was highest in K. globus ovalis ($1.2\pm0.2$ mg/g). The major fatty acids were 16:0, 22:1, 20:1, 18:1, 20:5 and 22:6 were identified as small amounts (1.0-3.3%) of total fatty acids. Citrulline was shown to be the major free amino acids (20.4-53.1%).

• Environmental Analysis Health and Toxicology
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• 제13권3_4호
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• pp.133-142
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• 1998

Effects of phosphorous (P) and methylglyoxal (MG) on the cell number, dry weight, chlorophyll content, photosynthetic and respiratory rate, phosphate uptake and protein content of green algae (Scenedesrnus obliquus) were studied. The algal cell number from the medium treated with 0.5-1.0 mM of MG at 1/2 P or 1/4 P concentration was significantly lower than those of algae treated :with full strength of phosphrous in medium. The inhibitory effect of MG on algal cell division was enhenced at low concentration of phosphorous in medium. At the beginning of logrithmic phase of algal growth, the mean dry weight of algae from the medium without MG-treatment in 1/2 P media was significantly higher than that of algae treated with MG. After logrithmic phase of growth cycle, the mean dry weight of algae from the medium with 1.0 mM of MG-treatment in 1/4 P media was significantly lower than that of algae treated with or without MG. At logrithmic phase of algal growth, there were significant differences in the chlorophyll content among all groups of tested algae with various concentrations of P and MG. At 15 days after inoculation, the mean chlorophyll content per algal cell from the media without MG-treatment in 1/2P was significantly higher than that of other cells from MG-treated media. The adverse effect of MG at concentration of 0.5-1.0mM in 1/2 and 1/4 P media on photosynthetic rate was observed. The mean photosynthetic rate of algal cell without P and MG treatment at 15 days after inoculation was significantly higher than that of MGtreated algae. After logarithmic phase, the algal cell treated with 0.5mM of MG with full strength of phosphorous showed significantly high respiratory rate than that of other cell groups. There were significant differences in mean phosphate uptake rate among all groups of Scenedesmus obliquus at logarithmic phase. At 12 days after inoculation, phosphate uptake rate per each algal cell from the basic media without MG and P treatment was rapidly reduced which shows early introduction to stationary phase.

• Biotechnology and Bioprocess Engineering:BBE
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• 제8권2호
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• pp.94-100
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• 2003

We studied the effect of cadmium on chlorophylls and rubisco activation in Canavalia ensiformis L. leaves. Chlorophyll levels were reduced by 5.0 ${\mu}$M Cd. Rubisco activity at 5.0 ${\mu}$M Cd was significantly smaller than that at no treatment. Rubisco Content showed patterns of change similar to rubisco activity. These data suggest that rubisco activity was associated with an amount of rubisco protein, and that the activation and induction of rubisco is inhibited by Cd. The degree of intensity of 50 and 14.5 kD polypeptides identified as the large and small subunit of rubisco by SDS-PAGE analysis at 5.0 ${\mu}$M Cd was significantly lower than that at control, indicating Cd had a e f-fect on both subunits. Under the assumption that effects of Cd on rubisco may be r elated to rubisco activase, in addition to, its activity and content we re determined . The rubisco activase activity at 5.0 ${\mu}$M Cd was more decreased than the control. A similar change pattern was also observed in content of rubisco activase. Remarkable differences in the intensitiy of both the 45 kD and 41 kD band were found between at control and Cd-treatment. These results suggest that the change in the levels of rubisco activase leads to a subsequent alter action of rubisco levels.