• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.3
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• pp.441-452
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• 1996

The effects of chlorophyll, tocopherols($\alpha$-tocopherol, ${\gamma}$-tocopherol and $\delta$-tocopherol), carotenoids ($\beta$-carotene and lutein), light sources, light intensities and strage temperatures on the photooxidative stability of soymilk were studied by measuring TBA value and depleted headspace oxygen(DHO) of soymilk. The samples were stored in the light storage box for 6 days and evaluated for the photooxidative stabilities. As the concentrations of chlorophyll increased, TBA value and DHO of the sample increased significantly(p<0.05), indicating chlorophyll acting as a photosensitizer. However, as the concentrations of tocopherols ($\alpha$-tocopherol, ${\gamma}$-tocopherol and $\delta$-tocopherol) and carotenoids ($\beta$-carotene and lutein) increased, TBA values and DHO of the samples decreased significantly(p<0.05). The light screening effects of carotenoids on DHO in the samples were not significantly different from the control at p>0.05. Therefore, there was no light screening effects of carotenoids on the oxidative stability of soymilk. The results indicate that tocopherols and carotenoids reduce the photooxidative stability of soymilk. $\delta$-Tocopherol was the most effective in photosensitized oxidation followed by ${\gamma}$-and $\alpha$-tocopherols in the order of increasing stability. $\beta$-Carotene was significantly(p<0.05) more effective than lutein in minimizing the chlorophyll-sensitized photooxidation of soymilk. Visible light was more effective than UV light in decreasing the photooxidative stability of soymilk. Therefore, photooxidation of soymilk containing chlorophyll is mainly due to photosensitized oxidation rather than photolysis reaction. As the intensities of fluorescence light increased, TBA values and DHO of the samples increased significantly at P<0.05. However, as the storage temperatures increased, TBA values and DHO of soymilk did not change significantly at p>0.05.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.197-202
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• 1996

The effects of erythrosine on the oxidative stability of cholesterol in an aqueous model system were studied by depleted headspace oxygen and cholesterol oxidation products (COP). As the oncentration of erythrosine was increased, headspace oxygen depletion, 7-COP and total COP increased during storage at $25^{\circ}C$ for 50 hours under the fluorescent light. As the intensity of fluorescent light was increased, amounts of headspace oxygen depleted and COP formed in an aqueous cholesterol dispersion containing erythrosine also increased. Addition of ${\alpha}-,\;{\delta}-$, mixed-tocopherol and ${\beta}-carotene$ resulted in the enhanced oxidative stability of an aqueous cholesterol dispersion containing erythrosine during the fluorescent light storage.

• Journal of the East Asian Society of Dietary Life
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• v.7 no.4
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• pp.460-467
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• 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 Life Science
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• v.5 no.2
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• pp.70-75
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• 1995

The effect of lipoxygenase (LOX) on the oxidation and co-oxidation of lipid fraction was studied in the model system of rainbow trout. For the reaction in model system 1 g of lipid fraction and 50mL of enzyme extract(LOX, 140 unit in 50mL phosphate buffer solution at pH 7, 4)), which were obtained from rainbow trout, were homoginized in the presence of Tween 20 and kept at 23$\circ$C for 3 days. The activity of LOX was decreased to 43% of initial level during the reaction in the model system. The initial composition of rainbow trout lipid was showed to be consisted of trigliceride(TG;82%) and free fatty acid(FFA;0.1%), while this converted to 59% of TG and 20% of FIFA, respectively after reaction in model system. Change of fatty acid composition was also observed and the content of linoleic acid, one of the major fatte acids, was decreased to 13% from 54% in the content of total fatty acids after reaction. The carotenoids in rainbow trout were composed of 0.4% $\alpha$-carotene, 1.6% $\beta$ -carotene, 80% canthaxanthin, 7% lutein and 11% zeaxanthin, thus the canthaxanthin was the major component. This canthaxanthin was the most degraded carotenoid by lipoxygenase catalyzed co-oxidation during the reaction. On the other hand the tocopherol isomers found in the rainbow trout were $\alpha$ and $\beta$ -tocopherol, and $\alpha$-tocopherol had a higher degradation rate by the lipoxygenase catalyzed co-oxidation than of $\beta$-tocopherol in the reaction of model system.

• Korean Journal of Food Science and Technology
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• v.47 no.1
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• pp.1-5
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• 2015

This study aimed to simultaneously determine various carotenoids from different colored paprika using an ultra performance liquid chromatograph (UPLC) equipped with a HSS T3 column. Analysis was performed at 450 nm using gradient conditions with acetonitrile/methanol/methylene chloride (65/25/10) and distilled water. We improved the peak resolution and performed carotenoid analysis within 30 min. We qualitatively analyzed 11 carotenoids (neoxanthin, capsorubin, violaxanthin, capsanthin, zeaxanthin, lutein, ${\alpha}$-cryptoxanthin, ${\beta}$-cryptoxanthin, lycopene, ${\alpha}$-carotene, and ${\beta}$-carotene). For the validation of UPLC methods, we validated the precision and accuracy of capsanthin. Capsanthin showed good linearity ($R^2$=0.9998) in the concentration range of $1-200{\mu}g/mL$ with 2.4 and $7.2{\mu}g/mL$ of limit of detection (LOD) and limit of quantification (LOQ), respectively. The relative standard deviation (RSD) for intra- and inter-day precision was less than 3.83%. Recovery was in the range of 91.86-99.87%. We quantitatively analyzed carotenoid contents from 8 different colored paprika (red, orange, yellow, and green). The most abundant carotenoids were capsanthin in red paprika, and zeaxanthin in orange, yellow, and green paprika.

• Applied Biological Chemistry
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• v.29 no.3
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• pp.260-265
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• 1986

Thermal degradation of ${\beta}-carotene$, major carotenoid present in cured tobacco leaves, were carried out at $400,\;600,\;and\;800^{\circ}C$ which are similar to temperatures existing in the combustion zones of cigarettes, and subsequent volatile degradation products were analyzed by combined gas chromatography-mass spectrometry. The volatile compounds identified from degradation products included 36 aromatic hydrocarbons, 10 ${\beta}-ionone-related$ compounds which have trimethylcyclohexane ring, and 7 others. Of these, 37 compounds including ${\beta}-cyclogeraniol$ had not been previously reported in the literature as thermal degradation products of ${\beta}-carotene$. The major compounds of degradation products at $400\;and\;600^{\circ}C$ were ${\beta}-xylene,\;{\alpha}-terpinene,\;{beta}-cyclocitral,\;ionene\;(1,2,3,4-tetrahydro-1,1,6-trimethyl\;naphthalene),\;{\beta}-ionone$, and dihydroactinidiolide. The major compounds at $800^{\circ}C$ were the above six compounds plus toluene.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.880-886
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• 1999

The present study was attempted to investigate the contents of antioxidant nutrients in green juice of Angelica keiskei, kale, carrot, celery, cucumber. All 5 green juice were found to contain antioxidant nutrients such as ${\beta}-carotene$, vitamin E, vitamin C, Se, Cu, Mn, Zn and phenols. ${\beta}-carotene$ contents of carrot, kale, Angelica keiskei, celery and cucumber juice were 5909.0, 3285.3, 1398.4, 176.7 and 61.4 mg/l00 g, respectively. ${\alpha}-tocopherol$ contents of 5 green juices were $0.04{\sim}1.41$ mg/l00 g. Kale juice had highest ${\alpha}-tocopherol$ and celery juice contained lowest, kale juice also contained highest vitamin C (105.1 mg/l00 g) and Angelica keiskei, cucumber, celery and carrot had vitamin C contents of 31.4, 9.3, 7.5 and 5.2 mg/l00 g, respectively. Angelica keiskei had highest amount of antioxidant minerals among the sample such as Cu (0.40 mg/l00 g), Mn (0.5 mg/l00 g), Zn (0.24 mg/l00 g), Se $(0.61\;{\mu}g/kg)$. Kale was the second best source of antioxidant minerals which were Cu (0.45 mg/l00 g), Mn (0.22 mg/l00 g), Zn (0.24 mg/l00 g), Se $(0.33\;{\mu}g/kg)$. However, celery and cucumber were poor in antioxidant minerals. Total phenolic contents of 5 green juices were $0.01\;{\sim}0.05%$, kale juice also had highest total phenolics among the samples.

• Preventive Nutrition and Food Science
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• v.6 no.1
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• pp.51-56
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• 2001

This study was carried out to evaluate whether antioxidant nutrient suppplementation with $\alpha$-tocopherol, vitamin C, $\beta$-carotene, and selenium reduces the lipid peroxide levels and increases the antioxidative enzyme activities in patients with coronary hart disease. Eighty nine patients participated in a randomized, double-blind, placebo-controlled trial. The antioxidant group (45 patients) was given daily doses of $\alpha$-tocopherol (400 IU), vitamin C (50 mg), $\beta$-carotene (15 mg), and selenium (50 $\mu\textrm{g}$) and forty four patients received a placebo. Thirty eight subjects (84.4%) of the antioxidant group and thirty nine subjects (88.6%) of the placebo group completed the three-month supplementation. Serum levels of tocopherol, vitamin C and $\beta$-carotene significantly increased in the antioxidant group compared with the baseline (p<0.05). Thiobarbituric acid-reactive substances(TBARS) decreased significantly (0.6 nmol MDA/mL) in the antioxidant group compared with that (0.09 nmol MDA/mL) in the placebo group (p=0.03). However, antioxidant supplementation did not affect the level of oxidized-LDL measured as autoantibodies against oxidized-LDL. The superoxide dimutase activity in red blood cells increased in the antioxidant group compared with the baseline (p<0.05). However, glutathione peroxidase activities did not change after supplementation in both groups, and catalase activity significantly decreased in the placebo group (p<0.05). These results suggest that antioxidant supplementation for 3 months with $\alpha$-tocopherol, vitamin C, $\beta$-carotene and selenium in patients with coronary heat disease may be partially protective against oxidative stress.

• Journal of Life Science
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• v.29 no.2
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• pp.231-238
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• 2019

This study evaluated the antioxidant activity of the extract and fractions of Alnus firma. Alnus firma had the highest total phenolic content ($452.80{\pm}7.01{\mu}g$ gallic acid equivalents/mg) in a methanol (MeOH) fraction and the highest total flavonoid content ($112.29{\pm}11.14{\mu}g$ rutin equivalents/mg) and antioxidant capacity ($936.23{\pm}0.07{\mu}g$ ${\alpha}$-tocopherol equivalents/mg) in an ethylacetate (EA) fraction. The antioxidant activities of various solvent extract fractions of Alnus firma were evaluated using various antioxidant assays, including ${\beta}$-carotene-linoleate assay, reducing power assay, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay, metal chelating activity assay, superoxide anion radical scavenging assay, and lipid peroxidation inhibition assay using the ferric thiocyanate method. These activities were compared with those of ascorbic acid, butylated hydroxyanisole (BHA), gallic acid (GA), butylated hydroxytoluene (BHT), and ${\alpha}$-tocopherol. First, at a $250{\mu}g/ml$ concentration, the EA and MeOH fractions of A. firma showed 92.43% and 89.20% DPPH radical scavenging activity, respectively. Second, $50{\mu}g/ml$ of the EA fraction exhibited 72.49% superoxide anion radical scavenging activity, a little greater than the same dose of GA (60.88%). Finally, 0.5 and 1 mg/ml of the EA fraction showed 73.45% and 73.29% inhibition of peroxidation in the ${\beta}$-carotene-linoleic acid system, respectively. The decreasing order of reducing power was EA fraction > n-butanol (BuOH) fraction > dichloromethane (DCM) fraction > n-hexane (HX) fraction. The results obtained in the present study indicated that Alnus firma can be used as an easily accessible potential source of natural antioxidants.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.4
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• pp.680-686
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• 1996

Investigations were conducted on the effects of different blanching solutions and time on tile quality of carrot juice to minimize undesirable changes in color, taste and flavor of raw carrot. Juice yields were 65.9% in raw juice(RJ), 51.7~55.3% in juice by blanching in water(JBIW) and 44.6% in juice by blanching in acetic acid solution(JBIA). pH of JBIW was 6.12~6.37, similar to RJ, while that of JBIA was 4.85. Soluble solid was in the decreasing order of RJ, JBIW and JBIA. Turbidities of JBIW for 1 min and JBIA for 5 min after 3 day storage at $4^{\circ}C$ were maintained by 94% compared to the original juice. Only 44~46% of $\beta-carotene$ was extracted from carrots during pressing, and f-carotene was extracted to a greater extent than $\alpha-carotene.$ Sensory evaluation indicated that JBIW for 1 min was superior to nth and commercially available juice in overall acceptance.