• Journal of Photoscience
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• v.12 no.1
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• pp.33-39
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• 2005

Plants possess the ability to dissipate the excitation energy for the protection of photosynthetic apparatus from absorbed excess light. Heat dissipation is regulated by xanthophyll cycle in thylakoid membranes of chloroplasts. We investigated the mechanistic aspects of xanthophyll cycle-dependent photoprotection against low-temperature photoinhibition in plants. Using barley and rice as chilling-resistant species and sensitive ones, respectively, chilling-induced chlorophyll fluorescence quenching, composition of xanthophyll cycle pigments and mRNA expression of the zeaxanthin epoxidase were examined. Chilled barley plants exhibited little changes in chlorophyll fluorescence quenching either of photochemical or non-photochemical nature and in the photosynthetic electron transport, indicating low reduction state of PS II primary electron acceptor. In contrast to the barley, chilled rice showed a marked decline in those parameters mentioned above, indicating the increased reduction state of PS II primary electron acceptor. In addition, barley plants were shown to have a higher capacity to elevate the pool size of xanthophyll cycle pigments in response to cold stress compared to rice plants. Such species-dependent regulation of xanthophyll cycle activity was correlated with the gene expression level of cold-induced zeaxanthin epoxidase. Chilled rice plants depressed the gene expression of zeaxanthin epoxidase, whereas barley increased its expression in response to cold stress. We suggest that chilling-induced alterations in the pool size of xanthophyll cycle pigments related to its capacity would play an important role in regulating plant's sensitivity to chilling stress.

• Korean Journal of Poultry Science
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• v.30 no.3
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• pp.177-182
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• 2003

This study was carried out to investigate the influence of dietary xanthophylls supplementation on the antioxidant and color properties of broiler meat. After raised for 6 weeks, broilers were slaughtered and stored at 3$^{\circ}C$ for 9 days. Experimental treatments were divided into lutein, canthaxanthin, astaxanthin and capsanthin. The supplementation level was adjusted to 30 ppm. The pH values of the thigh was higher(P<0.05) than those of the breast. No differences in pH values were shown among xanthophylls treatments. Xanthophylls supplementation to chick inhibited the formation of TBARS(Thiobarbituric acid reactive substance) and POV(lipid peroxide) of broiler meat during storage. At 9 day storage, the TBARS and POV of xanthophylls treatment decreased as compared to the control(P<0.05). The broiler meats fed astaxanthin had antioxidant effects in both breast and thigh. Dietary xanthophyll supplementation to chick decreased the CIE L(lightness) and increased a(redness) values of broiler meats fed canthaxanthin increased(P<0.05) during storage. These results indicated that broiler meats fed xanthophylls had dark-red color and antioxidant effect during refrigerated storage.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2002.11a
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• pp.87-89
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• 2002

This study was designed to investigate the antioxidant effects of dietary xanthophylls supplementation in broiler breast and thigh meat homogenates during incubation at 37$^{\circ}C$ for 0, 2, 4, 8, 16 hours respectively. Experimental treatments were divided into control, lutein, canthaxanthin, astaxanthin and capxanthin fed meats. The supplementation levels of to chicks were adjusted to 30 ppm in feeds. The 30 ${\mu}$M FeCl$_3$ and 100 ${\mu}$M ascorbic acid were added to meat homogenates in order to catalyze lipid oxidation. In breast meat homogenates, the TBARS(O.D) of all treatments at 2 hour was significantly(p〈0.05) increase. In thigh meat homogenates, the highest TBARS(O.D) value of all treatments appeared at 16 hour incubation and TBARS(O.D) value of all treatments was significantly(p〈0.05) lower than that control during incubation time. The TBARS(O.D) of lutein treatment in breast meat homogenate at 8 hour and 16 hour were significantly(p〈0.05) lower than those of treatments. Also, astaxanthin treated in thigh meat homogenate of the 2 hour and 4 hour and lutein treatment in thigh meat homogenate at 8 hour and 16 hour were significantly(p〈0.05) lower than other treatments. In conclusion, dietary xanthophyll treatments in breast and thigh meat homogenates showed more antioxidant effect to lipid oxidation than control. Especially, lipid oxidation inhibited significantly in lutein fed breast meat, and lutein and astaxanthin fed thigh meat homogenates.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.1 no.2
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• pp.73-79
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• 1968

The resolving capacities of xanthophyll pigments on thin-layers of Silica Gel, Hyflo super-Cel, and Micro-Cel C with varying concentrations of acetone in petroleum ether as the developing solvent were compared. The results showed that the resolving capacity of Micro-Cel C thin-layer was superior to others and satisfactory for the separation of leaf carotenoids in clearly separated six bands; carotenes, lutein-zeaxanthin, antheraxanthin, violaxanthin, an unidentified band, and neoxanthin, when it was developed with $13\%$ acetone-petroleum ether solution for 15 to 20minutes in an unsaturated chamber. Adhension of Micro-Cel C to glass was adequate without binder. Calcium sulfate used as a binder appeared to inactivate the resolving capacity of Micro-Cel C. Removing an about 0.2cm-wide layer on bo side of thin-layer slide helped to prevent 'edge effect' which gave tailing and faster solvent ascending along the side than the center. An adequate thickness of thin-layer was obtained when a 3 ml aliquot of the suspension in which l0g powdered Micro-Cel C was suspended in 75 ml distilled water was coated on a $2\times20cm$ glass slide.

• Journal of Photoscience
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• v.5 no.1
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• pp.17-22
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• 1998

Changes of chlorophyll fluorescence and xanthophyll cycle pigment contents in maize leaves were investigated dunng desiccation in darkness or in the light. In darkness, a drastic dehydration of detached maize leaves down to 50% relative water content (RWC) affected photochemical efficiency of photosystem II (Fv/Fm) and pht)tochemical quenching (qP) only slightly. In contrast, desiccation in the light with a moderate intensity led to a pronounced reduction in Fv/Fm with a Fo quenching when RWC was greater than 70%. This reduction in Fv/Fm could be recovered in darkness under hutrod condition. In leaves with RWC below 70%, significant reduction in Fv/Fm was accompanied by an increase of Fo, which could not be reversed within 5 h in darkness under humid condition. The nonphotochemical quenching increased during desiccation in the light with a concomitant rise in zeaxanthin at the expense of violaxanthin. Pretreatment with dithiothreitol (DTT), an inhibitor of zeaxanthin synthesis, inhibited the development of nonphotochemical quenching and prevented the xanthophyll interconversion during desiccation in the light. These results suggest that even light with a moderate intensity becomes excessive under dehydration and zeaxanthin-associated photoprotection of photosynthetic apparatus against photodamage is involved, but the protection is not complete against severe desiccation.

• Korean Journal of Weed Science
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• v.31 no.4
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• pp.323-329
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• 2011

We investigated photodynamic stress-induced antioxidant responses in transgenic rice overexpressing Bradyrhizobium japonicum 5-aminolevulinic acid synthase (ALA-S) coding sequence lacking plastidal transit sequence. High light of $350{\mu}mol\;m^{-2}\;s^{-1}$ decreased the quantum yield in the transgenic lines, C4 and C5, compared to that of wild-type line. By contrast, non-photochemical quenching (NPQ) levels of C4 and C5 under high light were higher than those of the transgenic lines under low light of $150{\mu}mol\;m^{-2}\;s^{-1}$ as well as wild-type line under low and high light. Greater levels of NPQ in the transgenic lines exposed to high light were in a close correlation with increases in the xanthophyll pigment, zeaxanthin. Under high light, levels of neoxanthin, violaxanthin, lutein, and ${\beta}$-carotene in the transgenic lines were lower than those in wild-type line. Taken together, nonphotochemical energy dissipation and photoprotectant xanthophyll pigments play a critical role to deal with the severe photodynamic damage in the transgenic rice plants, although they could not overcome the photodynamic stress, leading to severe photobleaching symptoms.

• Journal of Microbiology and Biotechnology
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• v.13 no.2
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• pp.165-174
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• 2003

Xanthophylls are oxygenated carotenoids that serve a variety of functions in photosynthetic organisms and are essential for survival of the organism. Within the last decade, major nor advances have been made in the elucidation of the molecular genetics and biochemistry of the xanthophyll biosynthesis pathway. Microalgae, yeast, or other microorganisms produce some of the xanthophylls that are being commercially used due to their own color and antioxidant properties. Currently, only a few microalgae are being considered or already being exploitd for the production of high-value xanthophylls. However, new developments in molecular biology have important implications for the commercialization of microalgae, and make the genetic manipulation of the xanthophyll content of microalgae mure attractive for biotechnological purposes. Accordingly, the current review summarizes the general properties of xanthophylls in microalgae and the recent developments in the biotechnological production of xanthophylls.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2002.05a
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• pp.125-125
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• 2002

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2002.05a
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• pp.126-126
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• 2002

• Proceedings of the Zoological Society Korea Conference
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• 1999.10b
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• pp.223.1-223
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• 1999

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