BACKGROUND/OBJECTIVES: Citrus and its peels have been used in Asian folk medicine due to abundant flavonoids and usage of citrus peels, which are byproducts from juice and/or jam processing, may be a good strategy. Therefore, the aim of this study was to examine antioxidant and anti-inflammatory effects of bioconversion of Jeju Hallabong tangor (Citrus kiyomi ${\times}$ ponkan; CKP) peels with cytolase (CKP-C) in RAW 264.7 cells. MATERIALS/METHODS: Glycosides of CKP were converted into aglycosides with cytolase treatment. RAW 264.7 cells were pre-treated with 0, 100, or $200{\mu}g/ml$ of citrus peel extracts for 4 h, followed by stimulation with $1{\mu}g/ml$ lipopolysaccharide (LPS) for 8 h. Cell viability, DPPH radical scavenging activity, nitric oxide (NO), and prostagladin $E_2$ ($PGE_2$) production were examined. Real time-PCR and western immunoblotting assay were performed for detection of mRNA and/or protein expression of pro-inflammatory mediators and cytokines, respectively. RESULTS: HPLC analysis showed that treatment of CKP with cytolase resulted in decreased flavanone rutinoside forms (narirutin and hesperidin) and increased flavanone aglycoside forms (naringenin and hesperetin). DPPH scavenging activities were observed in a dose-dependent manner for all of the citrus peel extracts and CKP-C was more potent than intact CKP. All of the citrus peel extracts decreased NO production by inducible nitric oxide synthase (iNOS) activity and $PGE_2$ production by COX-2. Higher dose of CKP and all CKP-C groups significantly decreased mRNA and protein expression of LPS-stimulated iNOS. Only $200{\mu}g/ml$ of CKP-C markedly decreased mRNA and protein expression of cyclooxygenase-2 in LPS-stimulated RAW 264.7 cells. Both 100 and $200{\mu}g/ml$ of CKP-C notably inhibited mRNA levels of $interleukin-1{\beta}$ ($IL-1{\beta}$) and IL-6, whereas $200{\mu}g/ml$ CKP-C significantly inhibited mRNA levels of $TNF-{\alpha}$. CONCLUSIONS: This result suggests that bioconversion of citrus peels with cytolase may enrich aglycoside flavanones of citrus peels and provide more potent functional food materials for prevention of chronic diseases attributable to oxidation and inflammation by increasing radical scavenging activity and suppressing pro-inflammatory mediators and cytokines.

BACKGROUND/OBJECFTIVES: The present study was conducted to examine the inhibitory effect of loquat leaves on MDA-MB-231 cell proliferation and invasion. MATERIALS/METHODS: Female athymic nude mice were given a subcutaneous (s.c.) inoculation of MDA-MB-231 cells and randomly grouped to receive a s.c. injection of either 500 mg/kg ethanol, water extract or vehicle five times a week. Tumor growth, mitotic rate and necrosis were examined. MDA-MB-231 cells were cultured with DMSO or with various concentrations of loquat water or ethanol extract. Proliferation, adhesion, migration, invasion and matrix metalloproteinase (MMP) activity were examined. RESULTS: Tumor growth of xenograft nude mouse was significantly reduced by loquat extracts. The results of mitotic examination revealed that loquat extracts reduced tumor cell division. Both ethanol and water extracts significantly inhibited MDA-MB-231 cell proliferation. The protein expression of ErbB3 was significantly down-regulated by loquat leaf extracts. Loquat leaf extracts increased apoptosis of MDA-MB-231 cells following 24 hour incubation and the ethanol extract was more potent in inducing apoptosis than the water extract. Furthermore, loquat extracts inhibited adhesion, migration and invasion of MDA-MB-231 cells. MMP activity was significantly inhibited by loquat extracts. CONCLUSION: Our results show that extracts of loquat inhibit the growth of tumor in MDA-MB-231 xenograft nude mice and the invasion of human breast cancer cells, indicating the inhibition of tumor cell proliferation and invasion.

BACKGROUND/OBJECTIVES: Bone formation and bone resorption continuously occur in bone tissue to prevent the accumulation of old bone, this being called bone remodeling. Osteoblasts especially play a crucial role in bone formation through the differentiation and proliferation. Therefore, in this study, we investigated the effects of Scytosiphon lomentaria extract (SLE) on osteoblastic proliferation and differentiation in MC3T3-E1 cells. MATERIALS/METHODS: A cell proliferation assay, alkaline phosphatase (ALP) activity assay, alizarin red staining and protein expression analysis of osteoblastic genes were carried out to assess the osteoblastic proliferation and differentiation. RESULTS: The results indicated that treatment of SLE promoted the proliferation of MC3T3-E1 cells and improved ALP activity. And, SLE treatment significantly promoted mineralized nodule formation compared with control. In addition, cells treated with SLE significantly upregulated protein expression of ALP, type 1 collagen, bone morphogenetic protein 2, runt-related transcription factor 2, osterix, and osteoprotegerin. CONCLUSIONS: The results demonstrate that SLE promote differentiation inducement and proliferation of osteoblasts and, therefore may help to elucidate the transcriptional mechanism of bone formation and possibly lead to the development of bone-forming drugs.

BACKGROUND/OBJECTIVE: We examined the hypoglycemic and anti-hyperlipidemic effect of yeast hydrolysate (YH) enriched with Cyclo-His-Pro (CHP) in the C57BL/6J ob/ob mouse model. MATERIALS/METHODS: Mice were separated into 4 groups (8 mice/group) on the basis of blood glucose and body weight: WT control, lean mice given vehicle; ob/ob control, ob/ob mice given vehicle; YH-1, ob/ob mice given 0.5 g/kg of YH; YH-2, ob/ob mice given 1 g/kg of YH. YH in saline or vehicle was administered orally in the same volume every day for 3 weeks. RESULTS: Mice treated with YH (0.5 and 1 g/kg) for 3 weeks displayed a significant reduction in overall body weight gain and perirenal and epididymal adipose tissue weight compared to the ob/ob control group. Additionally, high-density lipoprotein (HDL) cholesterol, glucose, and atherogenic indexes were significantly decreased in the blood of YH-1 and YH-2 groups compared to the ob/ob control. In ob/ob mice, YH administration significantly improved glucose tolerance and blood insulin levels. These data indicate that YH treatment produces potent hypoglycemic and anti-hyperlipidemic effects by controlling body weight, fat mass, blood lipid, insulin levels, and glucose tolerance. CONCLUSION: YH could potentially be used as a treatment option for diabetes and hyperlipidemia. The CHP-enriched YH may be a promising strategy in the development of hypoglycemic peptide nutraceuticals.

BACKGROUND/OBJECTIVES: Energy production and the rebuilding and repair of muscle tissue by physical activity require folate and vitamin $B_{12}$ as a cofactor. Thus, this study investigated the effects of regular moderate exercise training and durations of acute aerobic exercise on plasma folate and vitamin $B_{12}$ concentrations in moderate exercise trained rats. MATERIALS/METHODS: Fifty rats underwent non-exercise training (NT, n = 25) and regular exercise training (ET, n = 25) for 5 weeks. The ET group performed moderate exercise on a treadmill for 30 min/day, 5 days/week. At the end of week 5, each group was subdivided into 4 groups: non-exercise and 3 exercise groups. The non-exercise group (E0) was sacrificed without exercising and the 3 exercise groups were sacrificed immediately after exercising on a treadmill for 0.5 h (E0.5), 1 h (E1), and 2 h (E2). Blood samples were collected and plasma folate and vitamin $B_{12}$ were analyzed. RESULTS: After exercise training, plasma folate level was significantly lower and vitamin $B_{12}$ concentration was significantly higher in the ET group compared with the NT group (P < 0.05). No significant associations were observed between plasma folate and vitamin $B_{12}$ concentrations. In both the NT and ET groups, plasma folate and vitamin $B_{12}$ were not significantly changed by increasing duration of aerobic exercise. Plasma folate concentration of E0.5 was significantly lower in the ET group compared with that in the NT group. Significantly higher vitamin $B_{12}$ concentrations were observed in the E0 and E0.5 groups of the ET group compared to those of the NT group. CONCLUSION: Regular moderate exercise training decreased plasma folate and increased plasma vitamin $B_{12}$ levels. However, no significant changes in plasma folate and vitamin $B_{12}$ concentrations were observed by increasing duration of acute aerobic exercise.

BACKGROUND/OBJECTIVES: Despite the importance of a low-iodine diet (LID) for thyroid cancer patients preparing for radioactive iodine (RAI) therapy, few studies have evaluated dietary intake during LID. This study evaluated the amount of dietary iodine intake and its major food sources during a typical diet and during LID periods for thyroid cancer patients preparing for RAI therapy, and examined how the type of nutrition education of LID affects iodine intake. SUBJECTS/METHODS: A total of 92 differentiated thyroid cancer patients with total thyroidectomy were enrolled from Seoul National University Hospital. All subjects completed three days of dietary records during usual and low-iodine diets before $^{131}I$ administration. RESULTS: The median iodine intake was $290{\mu}g/day$ on the usual diet and $63.2{\mu}g/day$ on the LID. The major food groups during the usual diet were seaweed, salted vegetables, fish, milk, and dairy products and the consumption of these foods decreased significantly during LID. The mean energy intake on the LID was 1,325 kcal, which was 446 kcal lower than on the usual diet (1,771 kcal). By avoiding iodine, the intake of most other nutrients, including sodium, was significantly reduced during LID (P < 0.005). Regarding nutritional education, intensive education was more effective than a simple education at reducing iodine intake. CONCLUSION: Iodine intake for thyroid cancer patients was significantly reduced during LID and was within the recommended amount. However, the intake of most other nutrients and calories was also reduced. Future studies are needed to develop a practical dietary protocol for a LID in Korean patients.

BACKGROUND/OBJECTIVES: The anti-obesity effect of quercetin-rich onion peel extract (OPE) was suggested in rats, but information from human studies is limited. This study aimed to investigate the effects of OPE on the body composition of overweight and obese subjects. MATERIALS/METHODS: In this 12-week, randomized, double-blind, placebo-controlled study, parallel clinical trials were performed in overweight and obese Korean subjects. Randomly assigned subjects were instructed to take daily either the placebo (male, 6 and female, 30) or OPE capsules containing 100 mg of quercetin (male, 5 and female, 31). Body composition was measured by using bioimpedance and dual-energy X-ray absorptiometry (DXA). Resting energy expenditure (REE) and respiratory quotient (RQ) were evaluated by using indirect calorie measurement methods. Fasting blood levels of glucose, insulin, lipids, and leptin were determined. RESULTS: Quercetin-rich OPE supplementation significantly reduced the weight and percentage of body fat as measured by DXA (P = 0.02). These effects were not shown in the control group. Levels of blood glucose (P = 0.04) and leptin (P = 0.001 for placebo, P = 0.002 for OPE) decreased in both groups. Significant increases in REE and RQ were observed in both groups (P = 0.003 for placebo, P = 0.006 for OPE) and in the OPE group alone (P = 0.02), respectively. CONCLUSIONS: Quercetin-rich OPE supplementation changed the body composition of the overweight and obese subjects. This result suggests a beneficial role of the anti-obesity effect of OPE human subjects.

BACKGROUND/OBJECTIVES: Supplementation with n-3 polyunsaturated fatty acids (PUFAs) has been shown to generally decrease levels of innate immune markers and inflammatory cytokines, but the specific associations between blood levels of PUFAs and those of innate immune markers have not been investigated. Thus, the present study was conducted to test the hypothesis that innate immune markers as well as cytokines are negatively associated with n-3 PUFAs but positively associated with n-6 PUFAs in healthy adults. MATERIALS/METHODS: One hundred sixty-five healthy Korean adults aged 25-70 years old were included in this cross-sectional study. RESULTS: Serum levels of n-3 PUFAs, such as 18:3n3, 20:5n3, 22:5n3, and 22:6n3 were negatively correlated with eosinophil and basophil counts and $TNF-{\alpha}$, $IFN-{\gamma}$, IL-4, and IL-10 levels. Multivariate analysis also showed that serum levels of n-3 PUFAs were negatively associated with monocyte, eosinophil, and basophil counts and $TNF-{\alpha}$, $IFN-{\gamma}$, IL-4, and IL-12 levels. Additionally, the ratio of 20:4n6 to 20:5n3 was positively correlated with eosinophil counts and associated with $TNF-{\alpha}$, $IFN-{\gamma}$, and IL-4 levels. However, NK cell activity was not associated with serum fatty acid composition. CONCLUSIONS: Innate immune markers such as eosinophil, monocyte, and basophil counts were inversely associated with serum levels of n-3 PUFAs, but were positively associated with the 20:4n6/20:5n3 ratio in this population.

BACKGROUND/OBJECTIVES: The purpose of this study is to analyze daily kimchi, vegetable and fruit consumption by general characteristics and vegetable and fruit consumption from 1998 to 2012 by the Korean population based on the data of the KNHANES (Korea National Health and Nutrition Examination Survey). SUBJECTS/METHODS: This study is based on the 1998-2012 KNHNES. Analysis data on 54,700 subjects aged 19 years and older were obtained from health behavior interviews and the 24-hour dietary recall method. RESULTS: Daily kimchi consumption and portion size of kimchi decreased significantly from 1998 to 2012 (adjusted P for trend < 0.0001). Meanwhile, daily consumption of both non-salted vegetable and fruit with and without kimchi did not significantly change between 1998 and 2012. Reduced consumption of kimchi, non-salted vegetable, and fruit was observed for both genders as well as daily meal episodes and cooking locations. Male and female subjects with insufficient non-salted vegetable and fruit intake were increased 1.4 times and 1.3 times, respectively, in 2012 than 1998. All subjects consumed at least 400 g/day of non-salted vegetable, fruit, and kimchi in each survey year, although they consumed insufficient amounts (< 400 g/day) of non-salted vegetable and fruit without kimchi. CONCLUSIONS: Since Koreans generally consume high amounts of fermented vegetables, including kimchi, total vegetables and fruit. Consumption of these foods by the Korean adult population reached 400 g, which is the recommended intake of the WCRF/AICR. Based on this result, it is necessary to promote consumption of kimchi in the Korean population and research the development of low sodium kimchi in the future.

BACKGROUND/OBJECTIVES: A healthy diet has been reported to be associated with physical development, cognition and academic performance, and personality during adolescence. This study was performed to investigate the relationships among milk consumption and academic performance, learning motivation and strategies, and personality among Korean adolescents. SUBJECTS/METHODS: The study was divided into two parts. The first part was a survey on the relationship between milk consumption and academic performance, in which intakes of milk and milk products and academic scores were examined in percentiles among 630 middle and high school students residing in small and medium-sized cities in 2009. The second part was a survey on the relationships between milk consumption and learning motivation and strategy as well as personality, in which milk consumption habits were collected and Learning Motivation and Strategy Test (L-MOST) for adolescents and Total Personality Inventory for Adolescents (TPI-A) were conducted in 262 high school students in 2011. RESULTS: In the 2009 survey, milk and milk product intakes of subjects were divided into a low intake group (LM: ${\leq}60.2g/day$), medium intake group (MM: 60.3-150.9 g/day), and high intake group (HM: ${\geq}151.0g/day$). Academic performance of each group was expressed as a percentile, and performance in Korean, social science, and mathematics was significantly higher in the HM group (P < 0.05). In the 2011 survey, the group with a higher frequency of everyday milk consumption showed significantly higher "learning strategy total," "testing technique," and "resources management technique" scores (P < 0.05) in all subjects. However, when subjects were divided by gender, milk intake frequency, learning strategy total, class participation technique, and testing technique showed significantly positive correlations (P < 0.05) in boys, whereas no correlation was observed in girls. Correlations between milk intake frequency and each item of the personality test were only detected in boys, and milk intake frequency showed positive correlations with "total agreeability", "organization", "responsibility", "conscientiousness", and "intellectual curiosity" (P < 0.05). CONCLUSION: Intakes of milk and milk products were correlated with academic performance (Korean, social science, and mathematics) in Korean adolescents. In male high school students, particularly, higher milk intake frequency was positively correlated with learning motivation and strategy as well as some items of the personality inventory.

BACKGROUND/OBJECTIVES: Obesity, which is a known risk factor for many chronic diseases, has also been associated with vitamin D deficiency. This study explored the relationship between serum 25-hydroxy-vitamin D [25(OH)D] concentrations and adiposity measures in a general Korean population using the most recent, nationally representative survey data. SUBJECTS/METHODS: The study sample consisted of 4,771 Korean adults (${\geq}19years$) who participated in the fifth Korean National Health and Nutrition Examination Surveys. Serum 25(OH)D was determined by radioimmunoassay. Body mass index (BMI), waist circumference (WC) and total body fat content were measured as adiposity measurements. Total body fat content was measured by dual-energy X-ray absorptiometry. RESULTS: The serum 25(OH)D level was significantly higher in men than in women. Serum 25(OH)D concentration was positively correlated with energy intake, and it was negatively correlated with total body fat content (P < 0.0001) and percentage body fat (P < 0.0001) after adjustment for age in both sexes, while was inversely correlated with BMI only in women. In multivariable regression analysis, serum 25(OH)D was inversely associated with the total body fat content after adjustment for age, BMI, education, region, smoking, alcohol consumption, physical activity, and energy intake only in men (P = 0.0047). However, the serum 25(OH)D concentration was not associated with WC or BMI, indicators of adiposity after adjustment for potential risk factors. CONCLUSIONS: Serum 25(OH)D concentration was independently associated with the total body fat content in a general Korean population, but it may be not associated with the indicators for estimating adiposity, such as WC or BMI.

BACKGROUND/OBJECTIVES: Curcumin, an active ingredient in turmeric, is highly consumed in South Asia. However, curry that contains turmeric as its main spice might be the major source of curcumin in most other countries. Although curcumin consumption is not as high in these countries as South Asia, the regular consumption of curcumin may provide a significant health-beneficial effect. This study evaluated whether the moderate consumption of curry can affect blood glucose and lipid levels that become dysregulated with age. SUBJECTS/METHODS: This study used data obtained from the Korea National Health and Nutrition Examination Survey, conducted from 2012 to 2013, to assess curry consumption frequency as well as blood glucose and blood lipid levels. The levels of blood glucose and lipids were subdivided by age, sex, and body mass index, and compared according to the curry consumption level. The estimates in each subgroup were further adjusted for potential confounding factors, including the diagnosis of diseases, physical activity, and smoking. RESULTS: After adjusting for the above confounding factors, the blood glucose and triglyceride levels were significantly lower in the moderate curry consumption group compared to the low curry consumption group, both in older (> 45) male and younger (30 to 44) female overweight individuals who have high blood glucose and triglyceride levels. CONCLUSIONS: These results suggest that curcumin consumption, in an ordinary diet, can have health-beneficial effects, including being helpful in maintaining blood glucose and triglyceride levels that become dysregulated with age. The results should be further confirmed in future studies.

BACKGROUND/OBJECTIVES: This study measured the effects of a taste education program developed in Korea on food neophobia and willingness to try novel foods in school children. SUBJECTS/METHODS: One-hundred and twenty school children (aged 7-9 years) residing in Seoul participated in 12 sessions of a taste education program for 3 months. The Korean taste education program was adapted from "Les classes du gout" by J. Puisais and modified to suit a Korean education environment. The study subjected school children to pre- and post-programs on food neophobia and willingness to try novel foods (WTNF), in addition to children's food neophobia in their parents. A total of 101 survey data were analyzed using SPSS 18.0. RESULTS: Regarding the effects of taste education, scores of food neophobia significantly decreased (P < 0.01) in the posttest, mean (m) score ($4.10{\pm}1.19$) decreased compared to the pretest ($4.39{\pm}1.00$), and WTNF significantly increased (P < 0.001) in the pretest (m) score ($0.48{\pm}0.33$) compared to the pretest ($0.32{\pm}0.34$). This result indicates verification of the study hypothesis. CONCLUSIONS: Food neophobia scale (FNS), an index that measures personal food preference [1,2], showed a very weak correlation with behavioral willingness to taste novel foods (WTNF). Therefore, it is expected that the two scales measure different things. However, considering that the traits of food neophobia are not easily changed, the taste education program was administered in a remarkably effective manner.

BACKGROUND/OBJECTIVES: The purpose of this study was to find out the level of knowledge on sugar-related nutrition among mothers with preschool children. SUBJECTS/METHODS: The study conducted a survey on 350 mothers whose children attended daycare. The dietary lives of the children and the nutritional knowledge of the mothers on sugar were checked. In order to analyze results, SPSS 18.0 was used. ANOVA and t-test were also performed to analyze recognition and educational needs. RESULTS: When the degree of nutritional knowledge was measured and analyzed, the results showed about 11 average points out of 15. The higher a group's nutritional knowledge, the better the dietary habits and activities were and the activities were more ccommon. The group with a low level of nutritional knowledge consumed more foods with high sugar content, but this difference was not statistically significant. Also the children from the group of mothers that provided nutritional education to their children were more likely to engage in better dietary habits and activities. CONCLUSIONS: 66.5% respondents did not know about policies to reduce sugar consumption, but most indicated that education on reducing sugar consumption is needed. Therefore, a government-driven search for efficient methods to campaign and publicize sugar reduction is needed in order to continuously provide appropriate education.

BACKGROUND/OBJECTIVES: The current South Korean government policy on food irradiation technology should be reformed based on an in-depth investigation of the communications aspect, because the issue is no longer of a technological nature, given the proven safety and efficacy of the processes. SUBJECTS/METHODS: The target population of the education program consisted of elementary, middle, and high school students attending 310 schools in South Korea (2013: 63 schools, 2014: 104 schools, 2015: 143 schools). Data subjected to analysis were 13,327 pre-education and 12,641 post-education questionnaires received from 7,582 elementary, 2,671 middle, and 3,249 high school students who participated in the education program from May 2012 to April 2015 (n = 12,831), after the exclusion of inadequately filled-in questionnaires. RESULTS: Analysis of the three-year educational effect trend was conducted by comparing levels of variables before and after food radiation education. The analysis yielded the finding that the post-education levels were significantly higher for all variables. That is, for interest in education, perception (necessity, safety, subjective knowledge, and information acquisition), objective knowledge, and attitude, with the sole exception of objective knowledge in 2013. CONCLUSIONS: Given that post-education levels of perception, knowledge, and attitude concerning irradiated foods increased considerably compared to pre-education levels, behavior change should be induced by providing continuous education to enhance, these primary variables.