• ALGAE
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• v.17 no.2
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• pp.89-93
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• 2002

Seasonal changes of pigment compositionin two intertidal red algae, Gloiopeltis furcata (Postels et Ruprecht) J. Agardh, and Porphyra yezoensis Ueda, were investigated. Chlorophyll α and phycoerythrin levels were high during winter, but decreased in late spring or summer, with accompanying discoloration from deep red to green or yellow. This discoloation corresponded closely to the fluctuationof phycoerythrin content. Nevertheless, photosynthesis capacity was maintained by the increasing water temperature in the field, suggesting that large amounts of phycoerythrin are not necessary for photosynthesis. Phycoerythrin conten correlated significantly with nitrogen content in both species when the nitrogen level was greater than the level of critical content (1.30% DW in G. furcata, and 2.26% DW in P. yezoensis), indicating that phycoerythrin plays a more important role in the nitrogen status as a nitrogen pool than that of nitrogen critical content. Furthermore, the dependence level of the alage on phycoerythrin as a nitrogen pool was greater in P. yezoensis than in G. furcata because of the remarkable increase of phycoerythrin content in P. yezoensis with increasing jnitrogen content.

• Proceedings of the KSRS Conference
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• v.2
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• pp.1019-1022
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• 2006

Satellite sea ice data from 1978 to the present reveal that the perennial ice (or ice that survives the summer) has been rapidly declining at almost 10% per decade. Warming due to increases in greenhouse gases in the atmosphere is now also being reflected in winter with drastic reductions in the maximum extent observed in 2005 and 2006. The retreat of the perennial ice also exposes more open water and has revealed an asymmetric distribution of chlorophyll a pigment concentration in the Arctic basin. Phytoplankton blooms are most dominant at high latitudes, partly on account of sea ice, but in the Arctic basin, it appears that pigment concentrations in the Eastern (Laptev Sea) Region are on the average three times higher than those in the Western (Beaufort Sea) Region. Such asymmetry suggests that despite favorable conditions provided by the melt of sea ice, there are other factors that affects the productivity of the region. The asymmetry is likely associated with much wider shelf areas in the East than in the West, with sea ice processes that inhibits the availability of nutrients near the surface in deep water regions, and river run-off that affects nutrient availability. The primary productivity in the pan-Arctic region have been estimated using the pigment concentrations and PAR derived from SeaWiFS data and the results show large seasonal as well as interannual variability during the 1998 to 2005 period. The data points towards increasing productivity for later years but with only 9 years of data it is too early to tell the overall effect of the sea ice retreat.

• Textile Coloration and Finishing
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• v.23 no.2
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• pp.90-99
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• 2011

The aim of this study is to develope eco-printing method using natural pigments and chitosan as a natural binder. Three chitosans with different molecular weights were employed to find appropriate conditions including chitosan concentration and pigment/binder ratio. Dye uptake, color and fastnesses of the printed fabrics were evaluated to find optimum conditions within the range of experiments carried out in this study. The effectiveness of chitosan as a printing binder was examined in comparison with color, dye uptake, and fastnesses of conventional synthetic binder and guar gum. It was found that chitosans with low or medium molecular weight were appropriate. Using low molecular weight chitosan, optimum concentrations were 1.7% for charcoal, madder and chlorophyll, whereas 2.2% for ocher, yellow soil, indigo and cochineal. Regardless of molecular weight and concentration of chitosan, the color fastnesess of fabrics printed with mineral pigments were superior to those of the fabrics printed with plant and animal pigments. As pigment/chitosan ratio became higher, rubbing fastness was decreased by 1-3 grade. The colorfastness of printed fabric with chitosan binder was similar to that with synthetic binder, which was higher than that with guar gum.

• Applied Chemistry for Engineering
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• v.26 no.5
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• pp.533-537
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• 2015

Micro-algae Chlorella vulgaris (C. vulgaris) is an important source for bio-diesel because of the high content of neutral lipids. In this study, we intended to induce mutants of C. vulgaris by UV-B irradiation. C. vulgaris was first exposed to UV-B for 1, 2, 3, 4, 5 min. As the UV-B exposure time increased, the cell viability and pigment content were decreased. Mutants of C. vulgaris were also induced through ultraviolet irradiation and two strains were selected with respect to lipid contents, where were named as 'UM10', 'UM15'. They were then cultivated in the same way as to the wild type. After 21 days of cultivation, the cell growth, dry cell weight, pigment contents, and lipid contents were measured for investigating characteristics of mutants. As a result, the cell growth and dry cell weight of both mutants increased about 1.4 and 1.5 times, respectively compared with those of wild type. In addition, chlorophyll and carotenoid contents were measured in order to investigate pigment contents in micro-algae through photosynthesis. It was shown that chlorophyll and carotenoid contents of both mutants decreased about 10% compared to those of wild type. Lipid contents in UM10 and UM15 increased about 1.2 and 1.5 times, respectively compared to that of wild type.

• Journal of Photoscience
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• v.2 no.2
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• pp.103-106
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• 1995

For studying chlorophyll biosynthetic heterogeneity of plants, it is necessary to establish a technique for microassay of a putative monovinyl and divinyl protoporphyrin IX. Precise determination of the amounts of monovinyl and divinyl protoporphyrin IX is difficult with optical electronic spectroscopy even at 77$\circ$C. Such a problem could be solved by conversion of protoporphyrin IX to protoporphyrin IX dimethylester with diazomethane and subsequent Mg insertion into protoporphyrin IX dimethylester by reaction with a Grignard solution. The proportion of monovinyl and divinyl Mg-protoporphyrin IX dimethylester formed was measured instead of direct measuring that of protoporphyrin IX by low-temperature spectrofluorometry. The relative proportions of monovinyl and divinyl of protoporphyrin IX, Mg-protoporphyrin IX, and Mgprotoporphyrin IX dimethylester have not changed during the chemical conversion steps. This analysis system could be useful for the study of the monovinyl and divinyl chlorophyll biosynthetic routes in plants.

• 한국해양학회지
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• v.30 no.6
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• pp.529-536
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• 1995

A picophytoplankton has been isolated from the western channel of the Korea Strait. The cell was isolated by dilution method. It is about 2 ${\mu}m$ in diameter and has smooth surface. Organelles of nucleus, chloroplasts, mitochondrion, Golgi body, pyrenoids, vacuoles and lipid bodies are identified. Pigments are composed of chlorophyll a and chlorophyll b, ${\beta}$-carotene and other xanthophylls. Based on the ultrastructural features and pigment composition, it may belong to chlorococcalean picoplankton.

• Journal of Photoscience
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• v.1 no.1
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• pp.47-52
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• 1994

Effects of HgCl$_2$-treatment on electron transport, chlorophyll a fluorescence and its quenching were studied using isolated barley (Hordeum vulgare L. cv. Albori) chloroplasts. Depending on the concentration of HgCI$_2$, photosynthetic oxygen-evolving activities of photosystem II (PS II) were greatly inhibited, whereas those of photosystem I (PS I) were slightly decreased. The inhibitory effects of HgCl$_2$ on the oxygen-evolving activity was partially restored by the addition of hydroxyamine, suggesting the primary inhibition site by HgCl$_2$2-treatment is close to the oxidizing site of PS tl associated with water-splitting complex. Addition of 50 $\mu$M HgCI$_2$ decreased both photochemical and nonphotochemical quenching of chlorophyll fluorescence. Especially, energy dependent quenching (qE) was completely disappeared by HgCl$_2$-treatment as observed by NH$_4$CI treatment. In the presence of HgCI$_2$, F'o level during illumination was also increased. These results suggest that pH gradient across thylakoid membrane can not be formed in the presence of 0 $\mu$M HgCl$_2$. In addition, antenna pigment composition might be altered by HgCl$_2$-treatment.

• Journal of Ginseng Research
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• v.32 no.4
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• pp.347-356
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• 2008

Forest-grown American ginseng (Panax quinquefolius L.) is exposed to daily and seasonal light variations. Our goal was to determine the effect of understory light changes on the maximum quantum yield of photosystem II, expressed as $F_v/F_m$, and photosynthetic pigment composition of two-year-old plants. Understory light photon flux density and sunfleck durations were characterized using hemispherical canopy photography. Our results showed that understory light significantly affected the $F_v/F_m$ of American ginseng, especially during the initial development of the plants when light levels were the highest, averaging 28 mol $m^{-2}d^{-1}$. Associated with low $F_v/F_m$ during its initial development, American ginseng had the lowest levels of epoxidation state of the xanthophyll cycle of the season, suggesting an active dissipation of excess light energy absorbed by the chlorophyll pigments. As photon flux density decreased after the deployment of the forest canopy to less than 10 mol $m^{-2}d^{-1}$, chlorophyll a/b decreased suggesting a greater investment in light harvesting pigments to reaction centers in order to absorb the fleeting light energy.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.3
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• pp.183-188
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• 2001

The deposition behavior and photoelectric response characteristics of chlorophyll a(Chl a) monolayers and multilayers were investigated under various film fabrication conditions. Chl a LB films were deposited onto quartz and pretreated ITO glass substrates under several fabrication conditions, including surface pressure and number of layers. The absorption spectra of Chl a in a solution state and solid-like state (LB films) were fairly consistent with each other, and two absorption peaks were found at 678 and 438nm, respectively. The prepared Chl a LB films were set into an electrochemistry cell equipped with a Pt plate as the counter electrode, and the photoelectric response characteristics were obtained and analyzed relative to the light illumination. By considering the resulting photocurrents, the optimal fabrication conditions for Chl a LB films were determined as 20mN/m of surface pressure and 20 layers. The action spectrum of the Chl a LB films was obtained in the visible region, and was found to be in good agreement with the absorption spectrum. The possible application of the proposed system as a constituent of an artificial color recognition device was suggested based on combining with the photoelectric conversion property of another light-sensitive biological pigment.

• Proceedings of the KSRS Conference
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• 1998.09a
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• pp.95-100
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• 1998

The purpose of this study is to describe the change of the spring bloom and oceanographic condition. The variation of pigment concentration derived from the satellite ocean color data has been analyzed. According to the movement of blooming area, blooming was very concerned with a rising trend of sea surface temperature and a supply of nutrients. A nutrient rich water carried by the Oyashio encounters with the warm Core ring, where mixings and blooms are observed. We examined the correlation by using the satellite observations of the temperature and chlorophyll-a for the spring seasons (May, June, July) of 1998 the off Sanriku area (38-43N, 141- l50E). Using the SeaWiFS data, we process the data into the level-3, which contains the geophysical value of chlorophyll-a. And chlorophyll-a data is mapped for the water between 110E and 160E, and 15N and 52N with a 0.08 * 0.05 degree grid for each image. And Sea Surface Temperature (SST) data is produced using the AVHRR onboard the NOAA. The SST is derived by the MCSST. Then, the data is mapped for the water as much as chi-a data. And these gridded image was made by detection of each water masses, which are Kuroshio Extension, the warm-core ring and the Oyashlo Intrusion, etc., using those satellite images to determine short term change. Off Sanriku is a place where warm-water pool and the Oyashio at-e mixed. When warm streamer has intruded in cold water, the volume of phytoplankton increases at the tip of warm streamer. Warm water streamer was trigger of occurring blooming. And also, SeaWiFS images provided as much information for the studies of chlorophyll-a concentrations in the surface.