• 전기의세계
• /
• v.20 no.4
• /
• pp.23-30
• /
• 1971

The photovoltaic behaviors ahve been observed with a sandwich-type cell, consisting of a junction between .betha.-carotene and stannic oxide conducting layer to provide a junction electrode. In the stannic oxide and .betha.-carotene junction it was found that its electromotive forse decreased to a value smaller than the original one. This is due to a space charge formation. Photovoltage reached approximately 40mV with an irradiation energy of 250Kcal/M$^{2}$hr. It appeared that a magnitude of the photovoltaic response was proportional to the logarithm of irradiance. The time constant of the photovoltaic effect was shown to be approximately 0.7 sec. The wavelength dependence of the photovoltaic behavior was very anomalous. It is assumed that such an anomalous photoresponse depends on a internal capacitance due to some bubble during process to make a cell.

• Journal of the Korean Chemical Society
• /
• v.20 no.6
• /
• pp.514-519
• /
• 1976

Two more major pigments, lutein and 3,3'-dihydroxy-3,4,3',4'-bisdehydro-${\beta}$-carotene, were isolated from the abdominal skin of Bombina Orientalis and their structures were established by physical and chemical properties, visible and IR spectral characteristics and chromatographic behaviors.

• Journal of the Korean Chemical Society
• /
• v.18 no.5
• /
• pp.368-372
• /
• 1974

Dark red extract of abdominal skin of Bombina Orientalis was separated and purified with TLC, PLC(preparative thin layer chromatography) and column chromatography. Through the physical and chemical properties, visible and infrared spectral characteristics the third major pigment was identified as ${\alpha}$-cryptoxanthin(3-hydoroxy-${\alpha}$-carotene)

• Journal of Plant Biology
• /
• v.16 no.1_2
• /
• pp.30-38
• /
• 1973

To study the response to plant growth by the environmental factors, the effects of application of nitrogen on changes in the yield, crude protein, amino acids, chlorophyll, carotene, total phosphorus, acid-soluble phosphorus, phospholipids, RNA, and DNA were investigated with westerworlds 9Lolium sublatum) and perennial rye-grasses (Lolium perenne). The amounts of dry weight, crude protein, amino acids, chlorophyll, carotene, total phosphorus, acid-soluble phosphorus, phospholipids, RNA and DNA of both rye-grasses increased with adequately increasing nitrogen, and reached a maximum with an adequate application of nitrogen. The relationships between yields and crude protein contents, crude protein and RNA contents, and yields and RNA contents of westerworlds and perennial rye-grasses were found to be positively correlated, respectively. Therefore, in general, the response to plant growth by the environmental factors such as nitrogen nutrient may be summarized as follows: Environmental factors\longrightarrowDNA\longrightarrowRNA\longrightarrowProtein\longrightarrowPlant growth

• Journal of Microbiology
• /
• v.41 no.3
• /
• pp.212-218
• /
• 2003

Citrus phytoene synthase (CitPsy) and ${\beta}$-carotene hydroxylase (CitChx), which are involved in caroteinoid biosynthesis, are distantly related to the corresponding bacterial enzymes from the point of view of amino acid sequence similarity. We investigated these enzyme activities using Pantoea ananatis carotenoid biosynthetic genes and Escherichia coli as a host cell. The genes were cloned into two vector systems controlled by the T7 promoter. SDS-polyacrylamide gel electrophoresis showed that CitPsy and CitChx proteins are normally expressed in E. coli in both soluble and insoluble forms. In vivo complementation using the Pantoea ananatis enzymes and HPLC analysis showed that ${\beta}$-carotene and zeaxanthin were produced in recombinant E. coli, which indicated that the citrus enzymes were functionally expressed in E. coli and assembled into a functional multi-enzyme complex with Pantoea ananatis enzymes. These observed activities well matched the results of other researchers on tomato phytoene synthase and Arabidopsis and pepper ${\beta}$-carotene hydroxylases. Thus, our results suggest that plant carotenoid biosynthetic enzymes can generally complement the bacterial enzymes and could be a means of carotenoid production by molecular breeding and fermentation in bacterial and plant systems.

• Journal of the East Asian Society of Dietary Life
• /
• v.7 no.4
• /
• pp.460-467
• /
• 1997

The purpose of this study was to diagnose nutritional status of vitamin A in female university students. Total of 59 female students in Korea National University of Education, Home Economics Education department were recruited for this study. Retinol and :t major carotenoids in serum($\beta$-carotene, u-carotene, lycopene and lutein) were analyzed by HPLC. The isocratic separation was performed in a $\mu$ Bondapak$^{TM}$ $C_{18}$ stainless steel column with a solvent system of acetonitrile : methanol=85:15. The results of analysis were as follows: The average retinol concentration of 59 female students was 25.9$\mu\textrm{g}$/100$m\ell$. According to biochemical criteria for the assessment of vitamin A status, 18 of them belong to well-nourished and 6 students belong to adequate status. On the other hand, 8 students, 3 freshmen and 5 sophomore, were in critical vitamin A status. Retinol concentrations of junior and senior students were higher than those of freshmen and sophomore (P＜0.001). The average concentrations of serum $\beta$-carotene, lycopene, and lutein were 1.9, 5.4, and 41.4$\mu\textrm{g}$/100$m\ell$, respectively. Serum $\beta$-carotene concentration of senior was significant. higher than those of freshman, sophomore and junior(p＜0.001). Lycopene concentration of freshman was significant. lower than those of the other grades and that of senior was sig, higher than those of the other grades(p＜0.05). Lutein concentrations of junior and senior were significant. higher than those of freshman and sophomore(p＜0.001). The serum $\alpha$-carotene concentrations of the students were too low to analyze.e.

• Journal of Nutrition and Health
• /
• v.43 no.5
• /
• pp.443-452
• /
• 2010

Elevated plasma concentration of total homocysteine (ptHcy) is known as an independent risk factor of cardiovascular disease (CVD) and oxidative stress is also commonly implicated in CVD. An association between ptHcy and oxidative stress has recently been suggested. The study objective is to examine the relationship between ptHcy and oxidative stress markers in 103 healthy college students (62 males and 41 females). Plasma levels of ptHcy, oxidative stress markers (conjugated diene, erythrocyte catalase, TRAP, lymphocyte DNA damage), antioxidant vitamins ($\alpha$-tocopherol, $\gamma$-tocopherol, carotenoids), and lipid parameters (total cholesterol, triglyceride, HDL cholesterol) were determined. The results show that the concentration of ptHcy was significantly higher in male subjects ($22.17\;{\pm}\;2.14\;{\mu}mole/L$) than in female subjects ($12.28\;{\pm}\;0.45\;{\mu}mole/L$). There was a negative association between ptHcy and plasma ${\beta}$-carotene in male subjects (p $lt; 0.05), but no correlation between ptHcy and other plasma antioxidant vitamin levels in either gender. However, there were the negative correlations between ptHcy and plasma ${\alpha}$-carotene or ${\beta}$-carotene, and a positive correlation between ptHcy and lymphocyte DNA damage. A significantly low level of ${\alpha}$-carotene or ${\beta}$-carotene was found in male subjects with elevated ptHcy (${\geq}\;15\;{\mu}mol/L$), as compared to those with lower plasma homocysteine. These study results confirmed the views on the association between plasma homocysteine and oxidative stress markers in humans and support the hypothesis that homocysteine promotes the oxidative environment by counteracting the antioxidant defense mechanism.

• Journal of Microbiology and Biotechnology
• /
• v.30 no.6
• /
• pp.868-877
• /
• 2020

Bicarbonate has been considered as a better approach for supplying CO₂ to microalgae cells microenvironments than gas bubbling owing to cost-effectiveness and easy operation. However, the β-carotene production was too low in Dunaliella salina cultivated with bicarbonate in previous studies. Also, the difference in photosynthetic efficiency between these two carbon sources (bicarbonate and CO₂) has seldom been discussed. In this study, the culture conditions, including NaHCO₃, Ca²⁺, Mg²⁺ and microelement concentrations, were optimized when bicarbonate was used as carbon source. Under optimized condition, a maximum biomass concentration of 0.71 g/l and corresponding β-carotene content of 4.76% were obtained, with β-carotene yield of 32.0 mg/l, much higher than previous studies with NaHCO₃. Finally, these optimized conditions with bicarbonate were compared with CO₂ bubbling by online monitoring. There was a notable difference in F_v/F_m value between cultivations with bicarbonate and CO₂, but there was no difference in the F_v/F_m periodic changing patterns. This indicates that the high concentration of NaHCO₃ used in this study served as a stress factor for β-carotene accumulation, although high productivity of biomass was still obtained.

• Korean Journal of Food Science and Technology
• /
• v.24 no.1
• /
• pp.37-41
• /
• 1992

Starch solid system was used to investigate the effects of lipoxygenase, linoleic acid and water activity on the oxidation of ${\beta}-carotene$ or ${\alpha}-tocopherol$. ${\beta}-carotene$ or ${\alpha}-tocopherol$ was co-oxidized severely with linoleic acid by lipoxygenase, and these were reduced to 19% and 5% of initial concentration, respectively, after 2 days storage at $a_w$ 0.72 in the system. The concentration of ${\beta}-carotene$ and the destruction rates were linearly correlated. However, the ${\beta}-carotene$ was very stable in the system without linoleic acid and lipoxygenase. The oxidation products of ${\alpha}-tocopherol$ were considered as ${\alpha}-tocopheryl$ quinone and ${\alpha}-tocopheryl$ dimer, and the level of ${\alpha}-tocopherol$ quinone increased as the reaction time increased.

• Journal of Nutrition and Health
• /
• v.33 no.2
• /
• pp.158-166
• /
• 2000

The effects of smoking and physical exercise on the plasma concentrations of lipid-soluble antioxidants were investigated in 62 healthy males, aged 34-65 years. Current smokers (n=21) and ex-smokers(n=16) had significantly lower plasma levels of carotenoids ($\alpha$-carotene, $\beta$-carotene, cryptoxanthin and lycopene), $\alpha$-tocopherol and ${\gamma}$-tocopherol than non-smokers (n=25). Plasma concentrations of retionl and ubiquinone (coenzyme Q10) were lower among ex-smokers and current smokers than among non-smokers, but the differences were not statistically significant. Regular physical exercise was associated with increased plasma levels of lipid-soluble antioxidants. Plasma concentrations of crytoxanthin, retinol and ubiquinone were significantly elevated in the group engaging in moderate amounts of exercise (more than 20 minutes per day) compared to the group engaging in small amounts of exercise (less than 10 minutes per day). Plasma $\alpha$-carotene, $\beta$-carotene, lycopene levels in the subjects were affected more by smoking than by exercise. However, plasma levels of cryptoxanthin, retinol and ubiquinone in the subjects were affected more by exercise than by smoking. These findings suggest than smoking may cause a decrease in plasma lipid-soluble antioxidants during neutralization of reactive oxygen species present in cigarette smoke and that poor exercise habits may accelerate this imbalance of oxidant/antioxidant homeostasis in middle-aged Korean men.