• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.9 no.5
• /
• pp.50-59
• /
• 2006

This study was initiated to investigate soil chemical properties under different soil systems. Data such as soil acidity(pH), electrical conductivity(EC), organic matter content(OMC), and cation exchange capacity(CEC) were analyzed with samples from multi-layer, USGA, and mono-layer systems. N, P, K and micronutrients were also measured. Multi-layer system was built up to 60-cm depth with rootzone layer, intermediate layer and two drainage layers. USGA system 45 centimeters deep was constructed with rootzone layer, intermediate layer and drainage layer. Mono-layer system, however, was made only with a 30-cm rootzone layer. Differences were observed in soil pH, EC, OMC, CEC and micronutrients. Soil pH was acceptable for turfgrass growth a year after establishment, being 5.5 to 6.5 in the study. Differences were greatly observed for EC among soil systems. Values of EC for multi-layer, USGA, and mono-layer systems were 39.79, 31.26 and 103.54 uS/em, respectively. The increase rate was approximately 4 to 8 times greater with mono-layer system than those with other two systems. Therefore, it was necessary to avoid micronutrient deficiency such as Fe, Mn etc. through an effective management program in mono-layer system because of its faster potential feasibility of salt accumulation. The greatest OMC was associated with USGA system, being 0.97% which was 11% over that of the other systems. Slight differences were observed for CEC among them. Mono-layer system produced 1.45 me/100g, 10.3% and 8.9% lower in CEC than those of multi-layer and USGA system, respectively. Micronutrients such as Fe, Zn, and Mn etc. were below the level required for turf growth, regardless of soil systems. It was considered that one year after turf establishment was not enough to build up micronutrients in sand-based soil systems to the normal level for a turf growth. These results demonstrate that intensive management program including grow-in concept fertilization should be integrated into sand-based soil systems, even after a year in establishment. Regular nutrient monitoring by soil analyses is a strong necessity to decide the kinds and amount of fertilizer. Also, strategic management program must be selectively employed according to sports turf soil systems.

• Journal of Nutrition and Health
• /
• v.41 no.2
• /
• pp.135-140
• /
• 2008

Cigarette smoke (CS) induces oxidative and nitrosative stress to the respiratory tract (RT) via both oxidants contained in CS and by CS-induced activation of RT inflammatory-immune pro-oxidant processes. CS exposure has been associated with reduced levels of plasma micronutrient antioxidants, in part due to an increased utilization and turnover of alpha-tocopherol (AT). It has been suggested that gamma-tocopherol (GT) may have an expanded spectrum of antioxidant activation compared to alpha-tocopherol (AT). In order to investigate effects of high GT supplementation as compared to AT, C57 BL/6 mice were fed control AT (35 mg/kg diet) or high GT (1,000 mg/kg diet) diet for 8-10 weeks and then exposed to 60 $mg/m^3$ CS, 6 hr/day for 3 days. AT and GT levels and their metabolites were measured at endpoints. High GT supplementation significantly reduced AT levels in plasma, liver and lung compared to AT. CS increased levels of AT and GT in plasma and lung of control AT group but decreased GT levels in lung of high GT supplemented group. Moreover, CS significantly decreased GT metabolite, gamma-CEHC. The results suggest that high GT supplementation have selective modulation of concentrations of vitamin E and its metabolite in plasma and lung but not in liver against in vivo CS exposure.

• Nutrition Research and Practice
• /
• v.10 no.1
• /
• pp.56-66
• /
• 2016

BACKGROUND/OBJECTIVES: Despite successes recorded in combating iodine deficiency, more than 2 billion people are still at risk of iodine deficiency disorders. Rural landlocked and mountainous areas of developing countries are the hardest hit, hence the need to explore and advance novel strategies such as biofortification. SUBJECTS/METHODS: We evaluated adoption, purchase, and consumption of iodine biofortified vegetable legumes (IBVL) using the theory of protection motivations (PMT) integrated with an economic valuation technique. A total of 1,200 participants from three land-locked locations in East Africa were recruited via multi-stage cluster sampling, and data were collected using two, slightly distinct, questionnaires incorporating PMT constructs. The survey also elicited preferences for iodine biofortified foods when offered at a premium or discount. Determinants of protection motivations and preferences for iodine biofortified foods were assessed using path analysis modelling and two-limit Tobit regression, respectively. RESULTS: Knowledge of iodine, iodine-health link, salt iodization, and biofortification was very low, albeit lower at the household level. Iodine and biofortification were not recognized as nutrient and novel approaches, respectively. On the other hand, severity, fear, occupation, knowledge, iodine status, household composition, and self-efficacy predicted the intention to consume biofortified foods at the household level; only vulnerability, self-efficacy, and location were the most crucial elements at the school level. In addition, results demonstrated a positive willingness-to-pay a premium or acceptance of a lesser discount for biofortification. Furthermore, preference towards iodine biofortified foods was a function of protection motivations, severity, vulnerability, fear, response efficacy, response cost, knowledge, iodine status, gender, age. and household head. CONCLUSIONS: Results lend support for prevention of iodine deficiency in unprotected populations through biofortification; however 'threat' appraisal and socio-economic predictors are decisive in designing nutrition interventions and stimulating uptake of biofortification. In principle, the contribution is threefold: 1) Successful application of the integrated model to guide policy formulation; 2) Offer guidance to stakeholders to identify and tap niche markets; 3) stimulation of rural economic growth around school feeding programmes.

• Korean Journal of Soil Science and Fertilizer
• /
• v.43 no.6
• /
• pp.937-944
• /
• 2010

Cu and Zn can be accumulated in plastic film house soils by long-term application of livestock manure or compost. The mobility and bioavailability of Cu and Zn accumulated in soils are strongly influenced by their chemical or geochemical species in soils. In order to assess the accumulation, mobility, and bioavailability of Cu and Zn in plastic film house soils, we determined their geochemical species using a sequential extraction, grouped into three pods: the total pool, the potentially mobil pool, and the mobil pool. Total contents of Cu and Zn, ranged from 14.9 to 53.1 mg $kg^{-1}$ for Cu and from 55.4 to 169 mg $kg^{-1}$ for Zn, lied by far below the soil contamination standards, but exhibited little accumulation compared with their geogenic concentrations. Mobile contents of Cu and Zn and their percentage of total contents were strongly affected by soil pH in addition to total contents and soil organic matter. Mobile contents of Cu, ranged from <0.01 to 1.71 mg $kg^{-1}$, showed their minimum between pH 5.0 and 6.0 and increased above pH 6.0 to 8.0. In contrast, mobile contents of Zn, varied from <0.01 to 12.4 mg $kg^{-1}$, showed their minimum above pH 7.0 and increased strongly with decreasing pH below 5.5~6.0. Potentially mobile and total contents of Cu and Zn rose with ascending soil organic matter. To assess ecological and toxic effects of Cu and Zn in soils, mobile and potentially mobile contents, as bioavailable and potentially bioavailable pools, should be considered more important than total contents.

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

• Nutrition Research and Practice
• /
• v.16 no.sup1
• /
• pp.113-125
• /
• 2022

In the current years, it has now become necessary to establish standards for micronutrient intake based on scientific evidence. This review discusses issues related to the development of the 2020 Dietary Reference Intakes for Koreans (KDRI) for magnesium (Mg), zinc (Zn), and copper (Cu), and future research directions. Following issues were encountered when establishing the KDRI for these minerals. First, characteristics of Korean subjects need to be applied to estimate nutrient requirements. When calculating the estimated average requirement (EAR), the KDRI used the results of balance studies for Mg absorption and factorial analysis for Zn, which is defined as the minimum amount to offset endogenous losses for Zn and Mg. For Cu, a combination of indicators, such as depletion/repletion studies, were applied, wherein all reference values were based on data obtained from other countries. Second, there was a limitation in that it was difficult to determine whether reference values of Mg, Zn, and Cu intakes in the 2020 KDRI were achievable. This might be due to the lack of representative previous studies on intakes of these nutrients, and an insufficient database for Mg, Zn, and Cu contents in foods. This lack of database for mineral content in food poses a problem when evaluating the appropriateness of intake. Third, data was insufficient to assess the adequacy of Mg, Zn, and Cu intakes from supplements when calculating reference values, considering the rise in both demand and intake of mineral supplements. Mg is more likely to be consumed as a multi-nutrient supplement in combination with other minerals than as a single supplement. Moreover, Zn-Cu interactions in the body need to be considered when determining the reference intake values of Zn and Cu. It is recommended to discuss these issues present in the 2020 KDRI development for Mg, Zn, and Cu intakes in a systematic way, and to find relevant solutions.

• Journal of Nutrition and Health
• /
• v.41 no.7
• /
• pp.634-664
• /
• 2008

This study investigated the effects of the nutrition education on body weight, visceral fat and diet quality in the postmenopausal women. The subjects (n = 101) were randomly divided into two groups: Nutrition education + Exercise (NEE) group (n = 51) and Exercise only (EO) group (n = 50). Nutrition education was consisted of counseling in portion control, food selection for low carbohydrate, high fiber food items and for the improvement in micronutrient intakes and diet quality. After 6 months, the reduction in the body weight and visceral fat area was significantly greater in the NEE than in the EO group. The NEE subjects were further divided into two groups according to the amount of visceral fat area reduction; high visceral fat area loss (HVL) group with a visceral fat area reduction 2.35% or greater and low visceral fat area loss (LVL) group with a reduction less than 2.35%. In the HVL group, the reduction in body weight, BMI, percent body fat, waist to hip ratio and visceral fat area was significantly greater than that in the LVL group. We observed a significant increase in the serum HDL-cholesterol level and a decrease in systolic blood pressure, fasting blood sucrose, total and LDL-cholesterol levels in the HVL group compared to the LVL group. The energyadjusted protein, fiber, calcium, vitamin $B_6$, vitamin C, vitamin E intakes were significantly increased in the HVL compared to LVL group. The index of nutritional quality (INQ) and mean adequacy ratio (MAR) were also increased in the HVL group compared to the LVL group. These results show that our nutrition education program was an effective intervention measure for the reduction of body weight and visceral fat, blood pressure, glucose and lipid levels in the blood and also for the improvement of nutrient intake and diet quality in postmenopausal women who are overweight.

• Journal of Nutrition and Health
• /
• v.36 no.8
• /
• pp.801-810
• /
• 2003

Chronic alcoholism is considered a common cause of malnutrition. Especially, micronutrient deficiency may playa critical role in the incidence of alcoholic liver diseases. This study was conducted to investigate the effect of folate deficiency and ethanol consumption on cholesterol metabolism and the antioxidative system in rats. Plasma concentration of total cholesterol was increased by ethanol administration in folate-fed rats. HDL-cholesterol tended to be higher in the folate-fed group, but it was not significant. The plasma and hepatic levels of malondialdehyde were increased after chronic ethanol feeding, but dietary folate depressed the plasma malondialdehyde content of rats. Ethanol or folate feeding did not significantly change alcohol dehydrogenase activity. But folate feeding increased catalase activity in ethanol-fed rats. There was no significant change in superoxide dismutase activity among the experimental groups. Glutathione peroxidase activity tended to decrease by chronic ethanol feeding, but dietary folate did not affectthe glutathione peroxidase activity of chronic ethanol-fed rats. Glutathionine-S-transferase activity was not affected by ethanol feeding or folate deficiency. The plasma and hepatic levels of retinol decreased after chronic ethanol feeding. The hepatic level of retinol significantly decreased in ethanol-fed rats by folate deficiency. The plasma level of $\alpha$-tocopherol tended to be low in the folate deficient group with ethanol feeding, but there was no difference among the experimental groups in the hepatic level of $\alpha$-tocopherol. These results demonstrate that chronic ethanol consumption changes the plasma cholesterol metabolism and antioxidative system of rats, and optimal folate feeding in ethanol-fed rats exerts protective effects to some extent.

• Journal of Nutrition and Health
• /
• v.42 no.8
• /
• pp.691-701
• /
• 2009

This study was conducted to evaluate the dietary quality of school-aged children from low-income families in comparison with those from higher income families. The socio-demographic and anthropometric data and one day 24-hour recall dietary intake data of 1,782 school-aged children were used for analysis from the data of 2001 National Health and Nutrition Survey. The children whose family had monthly household income 120% or lower than the 2001 Minimum Cost of Living were classified into Low Income Group (LIG), and the others were classified into Higher Income Group (HIG). The consumption levels of the food groups of the Korean Food Guide as well as the general nutritional status based on their weight and height, energy and nutrient intake were compared between LIG and HIG in elementary (n = 989), middle (n = 432), and high (n = 361) school-aged children, respectively. LIG tended to have lower weight, height, and BMI than HIG, but the difference was significant only in the weight and the BMI of the middle school-aged children. The energy intake of LIG didn't differ from that of HIG, but LIG consumed a higher percentage of energy from carbohydrate and a lower percentage of energy from fat than HIG. Some micronutrient intake was lower in LIG than HIG in case of the elementary and the middle school-aged children. The average numbers of servings of milk dairy products and fruits consumed by LIG were significantly lower than those consumed by HIG in the elementary and the middle school-aged children, and they were less than the respective recommended serving. The average number of servings of meat fish egg beans consumed by LIG was lower than that consumed by HIG in the middle and the high school-aged children, and it was also less than the recommended serving. The results suggested that the diet of children from low-income families should be intervened by strategies different from the other children in order to improve the consumption level of milk dairy products, fruits, and meat fish egg beans.

• Journal of Food Hygiene and Safety
• /
• v.25 no.3
• /
• pp.269-277
• /
• 2010

Selenium is an essential micronutrient for normal body function and functions as an essential constituent of selenoproteins. This study was carried out to investigate effect of selenium on the formation of colonic aberrant crypt foci (ACF) and tumor formation in a mouse model. Five-week old ICR mice were acclimated for one week and fed different selenium diet (0.02, 0.1, and 0.5 ppm) for 12 weeks. Animals received three intraperitoneal injections of azoxymethane (10 mg/kg B.W. in saline for 3 weeks), followed by 2% dextran sodium sulfate in the drinking water for a week. There were four experimental groups, including a normal control group and three different selenium levels groups. After sacrifice, the total numbers of aberrant crypt (AC) and ACF were measured in the colonic mucosa after methylene blue staining. The number of tumors was noted for tumor incidence. Liver selenium concentration was measured using ICP-AES method. Gutathione peroxidase (GPx) activity was determined using a GPx assay kit in the liver and colon. TUNEL assay and proliferating cell nuclear antigen (PCNA) staining were performed to examine the cell apoptosis and cell proliferation, respectively. Immunohistochemistry of $\beta$-catenin was also performed on the mucous membrane tissue of colon. The activity of GPx in the liver and colon was decreased in the selenium-deficient diet group while it was increased in the selenium-overloaded diet group. Apoptotic positive cells were increased in the selenium-overloaded diet group but decreased in the selenium-deficient diet group. PCNA staining area was decreased in the selenium-overloaded diet group. In addition, the $\beta$-catenin protein level in the selenium-deficient diet group was increased but decreased in the selenium-overloaded diet group. These results indicate that dietary selenium might exert a modulating effect on colon cancer by inhibiting the development of ACF and colon tumor formation in this mouse model.