• Journal of Environmental Science International
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• v.1 no.2
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• pp.145-155
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• 1992

The effect of various supplies of lead singly and in combination with aluminium on growth and chlorophyll biosynthesis was investigated in 7-day-old Vigna anguluris seedlings. Expose to 50 $\mu$N Pb or more drastically reduced root elongation rate. Significant depressions in root growth was observed within 1 day and no recovery of growth was seen over the duration of treatment period. Root elongation decreased depending on the Pb concentrations. Root growth inhibition was stronger than shoot growth inhibition. The initiation of lateral roots appeared to be more sensitive to Pb than the growth of main roots. Inhibition of root and shoot elongation by Pb was lessened by combined exposure of Pb and Al, suggesting that the presence of AA reverse the inhibitory effect of Pb alone. With the histochemical sodium rhodizonate method the rate of Pb uptake was dependent on the Pb concentration and exposure time of the roots to Pb salts. Pb was first deposited on the root surface and then translocated radially in the root cap cells. During a longer Pb administration (up to 72 h) Pb penetration was nonuniform, with accumulation within the cortex or endodermis. There was drastic reduction in chlorophyll content by Pb. The Pb inhibition of chlorophyll synthesis was concentration dependent. 5-Aminolevulinic acid dehydratase (ALAD) activity exhibited distinct inhibition from control. Reduction in chlorophyll content was accompanied by proportional changes in ALAD activity. Chlorophyll content and ALAD activity were less affected by combined exposure of Pb and Al, suggesting that Al has a protective effect against the inhibiting action of Pb on photosynthetic activity.

• Korean Journal of Plant Resources
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• v.18 no.3
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• pp.441-449
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• 2005

Photo system II (PSII) is one of the two photosynthetic reaction centers in the chloroplast of higher plants. The chlorophyll a/b-light harvesting complex serves primarily as an antenna for PSII. We isolated a cDNA that encodes a chlorophyll a/b-binding protein (Cab) from Panax ginseng. The small subunit consists of 935 nucleotides long and has an open reading frame of 795 bp with the deduced amino acid of 265 residues (pI 5.63), 28.6 kDa. The deduced amino acid sequence matched to the previously reported Cab genes. Their degree of amino acid identity ranged from 68 to $92\%$. Phylogenetic analysis based on the amino acid residues was showed that the ginseng Cab gene was grouped with P. persica (AAC34983), A. thaliana (AAD28771), G. hirsutum (CAA38025), G. max (AAL29886), and V. radiate (AAF89205).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.61 no.4
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• pp.270-276
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• 2016

The objective of this study was to find a rapid determination of the hot air stress in maize (Zea mays L.) leaves using a portable chlorophyll fluorescence imaging instrument. To assess the photosynthetic activity of maize leaves, an imaging analysis of the photochemical responses of maize was performed with chlorophyll fluorescence camera. The observed chlorophyll imaging photos were numerically transformed to the photochemical parameters on the basis of chlorophyll a fluorescence. Chlorophyll a fluorescence imaging (CFI) method showed that a rapid decrease in maximum fluorescence intensity ($F_m$) of leaf occurred under hot air stress. Although no change was observed in the maximum quantum yield ($F_v/F_m$) of the hot air stressed maize leaves, the other photochemical parameters such as maximum fluorescence intensity ($F_m$) and Maximum fluorescence value ($F_p$) were relatively lowered after hot air stress. In hot air stressed maize leaves, an increase was observed in the nonphotoquenching (NPQ) and decrease in the effective quantum yield of photochemical energy conversion in photosystem II (${\Phi}PSII$). Thus, NPQ and ${\Phi}PSII$ were available to be determined non-destructively in maize leaves under hot air stress. Our results clearly indicated that the hot air could be a source of stress in maize leaves. Thus, the CFI analysis along with its related parameters can be used as a rapid indicating technique for the determining hot air stress in plants.

• Journal of Life Science
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• v.7 no.4
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• pp.297-308
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• 1997

Role of plant hormones on the leaf senescence of Phaseolus vulgaris were investigated by measuring the disassembly of chlorophyll-protein complexes in detached leaves treated with NAA, GA$_{3}$ , or BA. The loss of chlorophyll that was characteristic of leaf senescence induced disassembly of chlorophyll-protein complexed. During dark-induced senescence, PSI complex was rapidly degraded after the early stage, whereas RC-Core3 was slightly increased until the middle stage and slowly decreased thereafter. And gradual degradation of trimeric LCHII progressed after the late stage of senescence. Exogenous application of NAA and GA$_{3}$ had little or no effect in protecting disassembly of chlorophyll-protein complexes during leaf senescence compared to control. However exogenous BA application strongly leaves. In the simultaneous treatment of plant hormones and light, BA application under illumination of light was most effective in the stability of chlorophyll-protein complexes, particularly PSI, LHCII, RC-Core2, RC-Core3 and SC-1. these results suggest, therefore, that simultaneous application of BA and light induced synergistic effect on the stability off chlorophyll-protein complexes during leaf senescence.

• Journal of agriculture & life science
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• v.45 no.2
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• pp.1-7
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• 2011

Three evergreen ground-cover species were tested and evaluated for cold acclimation with different lights in central Korea to enrich the varieties of ground cover plants for over-wintering. Nandina domestica which recently started to be planted in central Korea had high chlorophyll unit with shade condition in both locations, Banpo and Gwacheon during winter. Light condition had no influence on chlorophyll unit in Banpo after April, meanwhile full sun condition decreased chlorophyll unit significantly in Gwacheon, which is exposed to cold wind from north. Ophiopogon japonicas had more than double chlorophyll unit in shade condition compared to that in full light condition in both investigation areas in February. In addition, higher value of L and b in shade condition had been maintained than in full sun condition throughout investigation period. However, leaves in Gwacheon were de-colorized in full sun condition after over-wintering. Pachysandra terminalis had more higher chlorophyll unit in shade condition compared to in full sun condition in both investigation areas in February. But light conditions had not effect the difference of chlorophyll unit of Gwacheon in April. Therefore, The present results suggest that evergreen ground covers with shade condition would be used as landscape materials in the capital area.

• Journal of Ecology and Environment
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• v.47 no.3
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• pp.103-116
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• 2023

Background: This study analyzed the physiological adaptations of a woody plant, Vitex rotundifolia, in Goraebul coastal sand dunes from May to September 2022. Environmental factors and physiological of plants growing under field and controlled (pot) conditions were compared. Results: Photosynthesis in plants growing in the coastal sand dunes and pots was the highest in June 2022 and July 2022, respectively. Chlorophyll fluorescence indicated the presence of stress in the coastal sand dune environment. The net photosynthesis rate (P_N) and Y(II) were highest in June in the coastal sand dune environment and July in the pot environment. In August and September, Y(NPQ) increased in the plants in the coastal sand dune environment, showing their photoprotective mechanism. Chlorophyll a and b contents in the pot plant leaves were higher than those in the coastal sand dune plant leaves; however, chlorophyll-a/b ratio was higher in the coastal sand dune plant leaves than in the pot plant leaves, suggesting a relatively high photosynthetic efficiency. Carotenoid content in the coastal sand dune plant leaves was higher in August and September 2022 than that in the pot plant leaves. Leaf water and soluble carbohydrate contents of the coastal sand dune plant leaves decreased in September 2022, leading to rapid leaf abscission. Diurnal variations in photosynthesis and chlorophyll fluorescence in both environments showed peak activity at 12:00 hour; however, the coastal sand dune plants had lower growth rates and Y(II) than the pot plants. Plants in the coastal sand dunes had higher leaf water and ion contents, indicating that they adapted to water stress through osmotic adjustments. However, plants growing in the coastal sand dunes exhibited reduced photosynthetic activity and accelerated decline due to seasonal temperature decreases. These findings demonstrate the adaptation mechanisms of V. rotundifolia to water stress, poor soils, and high temperature conditions in coastal sand dunes. Conclusions: The observed variations indicate the responses of the V. rotundifolia to environmental stress, and may reveal its survival strategies and adaptation mechanisms to stress. The results provide insights into the ecophysiological characteristics of V. rotundifolia and a basis for the conservation and restoration of damaged coastal sand dunes.

• Journal of Korea Water Resources Association
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• v.57 no.1
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• pp.9-19
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• 2024

As using public monitoring data, analysing a trends of water quality change, establishing a criteria to determine abnormal status and constructing a regression model that can predict Chlorophyll-a, an indicator of eutrophication, was studied. Accordingly, the three freshwater lakes were selected, approximately 20 years of water quality monitoring data were analyzed for periodic changes in water quality each year using regression analysis, and a method for determining abnormalities was presented by the standard deviation at confidence level 95%. By calculating the temporal change rate of Chlorophyll-a from irregular observed data, analyzing correlations between the rate and other water quality items, and constructing regression models, a method to predict changes in Chlorophyll-a was presented. The results of this study are expected to contribute to freshwater lake water quality management as an approximate water quality prediction method using the statistical model.

• Applied Biological Chemistry
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• v.44 no.2
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• pp.73-80
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• 2001

Factors such as temperature $(20,\;60^{\circ}C)$), pH (4.5, 7.0), gaseous phase $(N_2,\;0_2)$, and light (0 lux, 5,000 lux), antioxidants and packaging conditions were investigated to study the effects of above factors on the chlorophyll components in spinach during storage. Regardless of other factors, as the storage temperature increased from $20^{\circ}C$ to $60^{\circ}C$ and pH decreased from 7.0 to 4.5, the contents of chlorophyll a and chlorophyll b in spinach decreased significantly (P<0.05). The amounts of chlorophyll a and chlorophyll b in spinach stored in nitrogen gas were significantly (P<0.05) lower than those in sample in oxygen phase. As the light intensity increased from 0 lux to 5,000 lux during storage, the contents of chlorophyll a and chlorophyll b in spinach significantly (P<0.05) decreased. The antioxidants reduced the degradation of chlorophyll a in a model system during dark storage by minimization of free radical oxidation. The effectiveness of antioxidants decreased as following orders; ${\alpha}-tocopherol$>ascorbic acid>${\beta}-carotene$>catechin>quercetin>rutin>kaempherol>caffeic acid>chlorogenic acid>p-coumaric acid>ferulic acid. The degradation of chlorophyll a in a model system during light storage was minimized by antioxidants due to the reduction of singlet oxygen oxidation. The antidiscoloring potential of antioxidants decreased as following orders; ${\beta}-carotene$>${\alpha}-tocopherol$>ascorbic acid>catechin>quercetin>rutin>kaem-pherol>caffeic acid>chlorogenic acid>p-coumaric acid>ferulic acid. The amounts of chlorophyll a and chlorophyll b in freeze dried spinach packed with polyethylene bag were significantly (P<0.05) lower than those in non-packed freeze dried spinach. The package of spinach in polyethylene bag with the combination of antioxidants could be used to minimize the degradation of chlorophyll components in spinach during storage.

• Journal of Korean Society of Forest Science
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• v.76 no.1
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• pp.11-16
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• 1987

With the purpose of pursuing the increase and decrease of chlorophyll a and chlorophyll b caused by application of the simulated acid rain treatment on Pinus koraiensis seedlings and Ligustrum obtusifolium cuttings, the experimental design of randomized block arrangement with three replications was implemented in the experimental field of Yesan National Agricultural Junior College, during the growing season of 1985. Pinus koraiensis seeds stratified in cool and moist condition were sown on pots, and in case of Ligustrum obtusifolium, C1/1 cuttings were potted for experimental use in the early spring. The regime of artificial acid rain, based upon precipitation frequency and density, was simulated from the learning of climatological data averaged from 30 years records. The spray of acid water containing pH values of 4.0 and 2.0 was initiated from the 1st of May and ended on the 31st of August. As control, ground water was also treated at the same time. To analyse the chlorophyll content, those leaves looking representative and unaffected by other harmful agents were sampled on the 18th of September, and UV-visible spectrophotometer was used. With decrease in pH values of acid rain, the content of chlorophyll a and chlorophyll b decreased in both species. The decrease in chlorophyll a could be confirmed through statistical significance, but not in chlorophyll b. And when we discussed the chlorophyll decrease index which was explained in detail in the paper, an attention might be given to similarly decreasing values in both chlorophyll a and chlorophyll b, according as pH levels of acid rain decreased. The ratios of chlorophyll a to chlorophyll b in both species were not affected by different pH leaves of acid rain.

• Korean Journal of Food Science and Technology
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• v.41 no.6
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• pp.700-705
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• 2009

Several studies have demonstrated that chlorophyll has many beneficial properties, including anti-inflammatory, anti-tumor, and antioxidant properties. Chlorophyll has been also shown to have an excellent chemopreventive potential against skin tumor. Its preventive mechanism against skin tumor, however, has not been examined in detail. Furthermore, the effects of chlorophyll on UVB-induced cellular responses have not been investigated. Solar UV radiation, in particular its UVB component, is the primary cause of many adverse biological effects, which is responsible for the photoaging and skin cancer. We investigated the preventive effects of chlorophyll a on UVB-mediated responses in human immortalized HaCaT kerationocytes and normal human fibroblast. We found that treatment of chlorophyll a markedly inhibited UVB-induced generation of reactive oxygen species and lipid peroxidation. Chlorophyll a also prevented UVB-induced MMP-1 expression and MMP-2 activation and increased Type I pN collagen synthesis. These results suggest that chlorophyll a is a potent candidate for the prevention and treatment of UVB-induced skin cancer and photoaging.