• Journal of Nutrition and Health
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• v.55 no.2
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• pp.201-210
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• 2022

Vitamin A (Vit A) is a lipid-soluble vitamin required for diverse normal body functions, including good vision, reproduction, growth, development, and cellular differentiation. The therapeutic effects of Vit A have been demonstrated for the treatments of inflammation, low immunity, and cancer. The present review discusses the scientific evidence for establishing the 2020 Dietary Reference Intakes for Koreans (KDRI) for Vit A, issues caused by unit change of Vit A, and suggestions for the 2025 KDRI revision. Due to the changes in the standard bodyweight observed in several age groups, the 2020 KDRI had minor revisions as compared to the 2015 KDRI. In the 2015 KDRI, the Vit A unit has changed from retinol equivalent (RE) to retinol activity equivalent (RAE) and the activity of carotenoids became half with RAE compared to RE due to this unit change. Since the Vit A intake of Koreans relies heavily on plant-based carotenoids, the dietary intake of Vit A in Koreans as determined by considering the RAE was much lower than values obtained with RE. The analysis for Vit A intake by the Korean National Health and Nutrition Survey only reflects intakes of retinol and beta-carotene. Thus, it would be necessary to include the consumption of other provitamin A, such as alpha-carotene and beta-cryptoxanthin. Moreover, assessing the amounts of Vit A in foods should be customized to Korean diets since there are seasonal variations in the carotenoid concentration of plants. Moreover, other factors such as age- and sex-specific intake data and considerations of baseline micronutrient status, body mass index, and dietary patterns should be considered for developing more precise KDRI. In particular, the Vit A requirement needs to be met by consuming diverse foods, including animal foods.

• Journal of Nutrition and Health
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• v.45 no.5
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• pp.452-461
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• 2012

There is increasing evidence that dietary factors in plant-based diets are important for the prevention of chronic disease. Especially, phytonutrients in fruits and vegetables have been recognized as major contributors for the decreased level of oxidative stress. In this study, the effect of switching the dietary habit to high consumption of fruits and vegetables were evaluated on the parameters of serum antioxidant status in healthy high school students. Forty one students participated in a randomized controlled trial and were assigned to the control group (n = 18) or the intervention group (n = 23). The intervention group was provided for 8 weeks with the main food source being whole grain and vegetables. Anthropometric measurements, blood parameters and dietary intakes were measured, and compared before and after study. After 8 weeks, weight and BMI were significantly decreased in the intervention group (p = 0.000). The serum diacron reactive oxygen metabolites (d-ROMs) test resulted in a significantly decreased level only in the intervention group (p < 0.05) after 8 weeks, but serum biological antioxidant potential (BAP) was increased significantly in both groups (p < 0.001). Intake of energy, total fat, cholesterol and sodium in the intervention group were significantly decreased after 8 weeks (p < 0.05). Also, the intervention group had significantly increased vitamin and phytonutrient intakes of all-trans-${\beta}$-carotene, ${\alpha}$-carotene, ${\alpha}$-tocopherol, ascorbic acid, and total phenols (p < 0.05). Overall, the results of this study suggest that whole grain, fruits, and vegetables supplementation showed improvement of the adolescent health.

• Food Science and Biotechnology
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• v.18 no.3
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• pp.630-635
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• 2009

This study was performed to analyze various antioxidants, to evaluate the antioxidative activities, and to measure the protective effect for gap junction intercellular communication (GJIC) to assess the functional potency of the cherry tomato. The ascorbic acid, lycopene, and ${\beta}-carotene$ were measured at $503.4{\pm}9.6$, $39.7{\pm}1.5$, and $7.4{\pm}0.3$ mg/100 g d.w., and ${\alpha}-$, ${\beta}+{\gamma}-$, ${\delta}-tocopherol$ contents were measured at $8.3{\pm}0.1$, $1.7{\pm}0.0$, and $0.1{\pm}0.0$ mg/100 g d.w., respectively. Cherry tomato extract using hexane/acetone/EtOH (2:1:1, CTE) exhibited a ABTS radical scavenging activity with an $IC_{50}$ value of $48.83{\pm}0.30\;{\mu}g/mL$. The cherry tomato protected against the inhibition of GJIC induced by $H_2O_2$ in WB-F344 rat liver epithelial cells, and the reduction in phosphorylated Cx43 was most clearly correlated with the concentration of CTE. These results demonstrated that the cherry tomato harbors a wealth of potent antioxidants and might be protect human body against the inhibition of the GJIC by toxic components.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.15 no.5
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• pp.396-404
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• 2022

Chrysanthemum coronarium L. contains various antioxidants such as beta-carotene, vitamins A and C, and polyphenols, and is known to have anti-inflammatory effects. Under the assumption that the PDRN contained in the extract can mediate the anti-inflammatory response, the mouse macrophages, RAW264.7 cells, were stimulated with LPS to induce the conversion to inflammatory cells, and then the addition of PDRN extracted from the extract was effective in inhibiting inflammation. It was analyzed whether there was The gene expression of IL-1β and TNF-α was used as an anti-inflammatory index, and the relative expression levels of each gene were confirmed by RT-PCR. As a result, RT-PCR confirmed the effect of PDRN-induced inhibition of inflammation in both IL-1β and TNF-α genes. Therefore, based on this study, it is considered to be a precedent data that can be developed as a treatment for inflammatory diseases, and it will be helpful in research and development of a treatment that can improve the anti-inflammatory mechanism.

• Advances in Traditional Medicine
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• v.8 no.3
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• pp.266-278
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• 2008

Erythrina stricta, a deciduous tree widely used traditionally in indigenous system of medicine for various ailments such as rheumatism, fever, leprosy, epilepsy etc. The leaves of Erythrina stricta was extracted with ethanol (70%) and used for the evaluation of various in vitro antioxidant assays which includes H - donor activity, nitric oxide scavenging, superoxide anion scavenging, reducing ability, hydroxyl radical, hydrogen peroxide scavenging, total phenolic content, total flavonoid content, total antioxidant activity by thiocyanate and phosphomolybdenum method, metal chelating, $\beta$-carotene bleaching, total peroxy radical assays. The pro-oxidant activity was measured using bleomycin-dependent DNA damage. Ex vivo models like lipid peroxidation and erythrocyte haemolysis were also used to study the antioxidant property of the extract. The various antioxidant activities were compared with suitable standard antioxidants such as ascorbic acid, butylated hydroxyl toluene, $\alpha$-tocopherol, curcumin, quercetin and Trolox. The generation of free radicals viz. $O_2^{{\cdot}-}$, $OH^{\cdot}$, $H_2O_2$, $NO^{\cdot}$ and peroxyl radicals were effectively scavenged by the ethanolic extract of Erythrina stricta. In all the methods, the extract offered strong antioxidant activity in a concentration dependent manner. The total phenolic content, flavonoid content and total antioxidant activity in Erythrina stricta were determined as microgram (g) pyrocatechol, quercetin and $\alpha$-tocopherol equivalent/mg respectively. The extract did not exhibit any prooxidant activity when compared with ascorbic acid. The results obtained in the present study clearly indicates that Erythrina stricta scavenges free radicals and reduces lipid peroxidation, ameliorating the damage imposed by oxidative stress in different disease conditions and serve as a potential source of natural antioxidant.

• Nutrition Research and Practice
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• v.1 no.1
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• pp.70-73
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• 2007

This study was conducted to determine the nutritional characteristics of horsemeat and bone meal in comparison with those of beef and pork presented by Dietary Reference Intakes For Koreans. Longissimus muscle and large metacarpal bone samples were collected from 20 fattened Jeju horses. Muscle samples were subjected to proximate analysis, assays for fatty acid profile and minerals, and bone samples to mineral assays. Horsemeal had similar levels of protein (21.1 vs 21.0 or 21.1%) and lower levels of fat (6.0 vs 14.1 or 16.1%) compared with beef or pork, respectively. Horsemeat had much higher levels of palmitoleic (8.2 vs 4.4 or 3.3%) and $\alpha-linolenic$ (1.4 vs 0.1 or 0.6%) acids than beef or pork, respectively. Linoleic acid was much higher in horsemeat (11.1%) and pork (10.1%) than in beef (1.6%). PUFA:SFA and n-6:n-3 ratios in horsemeat were 0.29 and 10.2, respectively. There were no big differences in mineral contents between horsemeat, beef and pork. For daily recommended mineral intakes of male adults (Dietary Reference Intakes For Koreans), phosphorus, sodium, potassium, iron, zinc and copper can be provided up to 24, 2.5, 6.7, 21, 26 and 40%, respectively, by 100 g raw horsemeat, but calcium and manganese levels are negligible. Horse cannon bone had much higher mineral contents especially in calcium (10,193 mg/100 g), phosphorus (5,874 mg/100 g) and copper (0.79 mg/100 g). Thiamin, riboflavin, niacin and retinol contents were 0.20, 0.21, 1.65 mg/100 g and $30{\mu}g/100g$, respectively. But ascorbic acid and beta-carotene were not detected. Our data demonstrated that higher levels of palmitoleic and $\alpha-linolenic$ acid in horsemeat than in beef and pork may be beneficial for human health. Horsemeat and bone meal are a good source of some minerals and vitamins.

• Journal of Nutrition and Health
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• v.43 no.6
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• pp.628-637
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• 2010

To determine vitamin A and E intakes and their food sources, dietary intakes were collected by three consecutive 24-hour recalls from 192 adults living in Seoul and Gyeonggi Province, Korea. The mean vitamin A, retinol and ${\beta}$-carotene intakes were $1240.1{\pm}1101.1\;{\mu}g$ retinol equivalent/day ($693.3{\pm}563.2\;{\mu}g$ retinol activity equivalent/day), $182.6{\pm}149.5\;{\mu}g$/day and $5443.3{\pm}6365.5\;{\mu}g$/day, respectively. Only 9.4% of the subjects consumed less than the Korean Estimated Average Requirement for vitamin A. The mean vitamin E intake was $6.03{\pm}2.54\;mg$ ${\alpha}$-tocopherol equivalent/day. The ${\alpha}$-tocopherol and ${\gamma}$-tocopherol intakes were $4.83{\pm}2.03$ and $5.57{\pm}3.41\;mg$/day, respectively. Most of the subjects (93.8%) consumed less than the Korean Adequate Intake for vitamin E. The major food sources of vitamin A were sweet potato, carrot, red pepper powder, spinach, and citrus fruit, and the top 30 foods provided 91.5% of total Plant foods provided 81.0% and animalderived foods 10.5% of the vitamin A intake from the top 30 foods. The major food sources of vitamin E were soybean oil, red pepper powder, Ramyeon (cup noodles), spinach, and egg. The top 30 foods provided 78.0% of total vitamin E intake. Plant foods provided 61.3% and animal-derived foods 15.9% of the vitamin E intake from the top 30 foods. In conclusion, the vitamin A intake of the Korean adults in this study was ge-nerally adequate, but the vitamin E intake of many subjects was inadequate. Therefore, nutritional education may be of benefit to Korean adults to increase their vitamin E intake.

• Journal of Nutrition and Health
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• v.49 no.4
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• pp.258-268
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• 2016

Purpose: The purpose of this study was to estimate dietary vitamin A intake and examine major food sources of vitamin A in Korean adults. Methods: Using data from the 2007~2012 Korea National Health and Nutrition Examination Survey, a total of 33,069 subjects over 19-years-old were included in this study. We estimated individual daily intakes of retinol, carotenoids such as ${\alpha}$-carotene, ${\beta}$-carotene, ${\beta}$-cryptoxanthin, lutein/zeaxanthin, and lycopene, and vitamin A by linking food consumption data with the vitamin A database of commonly consumed foods. We compared individual vitamin A intakes with the reference value of Dietary Reference Intakes for Koreans. Results: Average dietary vitamin A intakes of study subjects were $864.3{\mu}g$ retinol equivalent/day ($495.7{\mu}g$ retinol activity equivalent/day) in men and $715.0{\mu}g$ retinol equivalent/day ($403.6{\mu}g$ retinol activity equivalent/day) in women. Exactly 42.9% and 70.6% of total subjects consumed less vitamin A than the Estimated Average Requirement (EAR) based on retinol equivalent and retinol activity equivalent, respectively. The major food sources of vitamin A were Korean radish leaves, carrot, red pepper, and laver, and the top 20 foods provided about 80% of total vitamin A intake. Conclusion: This study provides basic data for estimation of vitamin A intake in Korean adults. Further research will be needed to analyze the association of insufficient or excess intakes of vitamin A and health problems in the Korean population.

• Korean Journal of Community Nutrition
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• v.11 no.2
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• pp.279-288
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• 2006

The role of free radicals in the progression of many diseases and aging has been given a great attention and total antioxidant status (TAS) has shown to be reduced with aging. The incidence of hypertension has shown to be relatively high in the aged population, and it is known to be associated with increased obesity and oxidative stress. The aim of this study was to examine the obesity indices and the total antioxidant status in hypertensive elderly (64y$\alpha$-tocopherol, $\beta$-carotene and ascorbic acid did not show their significant correlations with TAS. These results showed that the hypertensive elderly are prone to be obese and to have increased TAS. Due to unknown factors affecting TAS values, measurement of plasma TAS as a sole indicator of total antioxidant capacity is limited to fully understanding changes in the body's free radical trapping power. However, the results from the current study may suggest that hypertension and/or obesity might increase oxidative stress, followed by increased the body's total antioxidant defense system.

• Journal of Microbiology and Biotechnology
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• v.14 no.4
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• pp.715-721
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• 2004

Many food protein hydrolysates have been shown to have antioxidant activities, and recent research focuses on low molecular peptides produced during hydrolysis of food protein. Korean rice wine contains about 60-70% of protein at dry base and originates from raw materials. It has been suggested that the protein is transformed into low molecular weight peptides, and have antioxidant activity during fermentation. The objectives of this study were to evaluate the antioxidant activity of the pre-purified and purified peptides found in Korean rice wine and to identify the responsible peptides. The wine extract of Samhaeju, a traditional Korean rice wine made by low temperature fermentation, was evaporated at $35^{\circ}C$. The two methods employed in the evaluation of antioxidant activity were the DPPH radical scavenging method and the beta-carotene bleaching test. The pre-purified samples showed 808 AAC (Antioxidant Activity Coefficient) and 56.5% AOA (Antioxidant Activity), which were higher than $\alpha$-tocopherol (572 AAC and 78% AOA). The rice wine extract was separated by reversed-phase HPLC. The protective effect of the four most antioxidant active fractions were tested for t-butyl hydroperoxide induced oxidation of healthy human erythrocytes and the byproduct was determined by malondialdehyde formation. Fraction No.5 showed 35% lower MDA concentration as compared to the control. The peptides were further purified using consecutive chromatographic methods and 4 antioxidant peptides were isolated. The amino acid sequences of the peptides were identified as Ile-His-His, Val- Val-His(Asn), Leu-Val-Pro, and Leu(Val)-Lys-Arg-Pro. The AAC value of the synthetic form of the identified peptides was the highest for Ile-His-His.