• 대한지역사회영양학회지
• /
• 제13권2호
• /
• pp.276-287
• /
• 2008

Diabetic mellitus in an older population is associated with increased basal oxidative stress and free radical accentuated by hyperglycemic challenge. Enhanced free radical in diabetic elderly can cause the oxidative damage and such damage can be protected by antioxidant defense system. It is believed that vitamin C, A and E are the most abundant and effective antioxidants in human plasma. The purpose of this study was to determine the antioxidant status in Korean diabetic elderly using the case-control study. The antioxidant status was examined by determining plasma levels of antioxidant vitamins (vitamin C, A, E, ${\beta}$-carotene), total antioxidant status (TAS) and thiobarbituric acid reactive substance (TBARS) and intakes of vitamin C, A, ${\beta}$-carotene and retiol. Fasting glucose and HbA1c levels and serum lipid profiles (triglyceride (TG), total cholesterol, HDL-cholesterol and LDL-cholesterol) were also determined. Diabetic subjects were 122 elderly persons over 60 years old, visiting public health center, and control subjects were 96 healthy elderly persons living in Ulsan, Korea and they were matched by age, gender, smoking and drinking status. The diabetic and control subjects were divided into sub-groups according to the status of using diet therapy and vitamin supplement. The subjects were interviewed to collect data on their general characteristics, disease history, vitamin supplement, diet therapy and health-related habits by questionnaires. Their dietary intakes were obtained by means of semi-quantitative food frequency questionnaires (SQFFQ). Fasting plasma glucose and HbA1c levels were significantly higher in diabetes than in control subjects, and plasma total cholesterol level of diabetes was not significantly different from that of control subjects. However serum HDL cholesterol level of diabetes was significantly lower and serum TG level of diabetes was significantly higher than those of control group. The average vitamin A and ${\beta}$-carotene intakes of diabetes were significantly higher than those of control subjects. There was no significant difference in plasma vitamin C, ${\beta}$-carotene, and TBARS levels between two groups, but plasma vitamin A, E and TAS levels were significantly higher in diabetes than those in control group. Plasma vitamin A and TAS levels of diabetic subjects using diet therapy were higher than those of control using diet therapy, and plasma vitamin E, ${\beta}$-carotene and TAS levels of diabetic subjects using vitamin supplements were significantly higher than those of controls using vitamin supplements. These results suggested that diabetic mellitus could enhance antioxidant defences against reactive oxygen species and interest in healthy eating such as consumption of more antioxidant nutrients.

• 한국응급구조학회지
• /
• 제10권1호
• /
• pp.51-60
• /
• 2006

Background: The toxicity of paraquat has been known to be caused by oxygen free radicals which leads to the lipid peroxidation and multiple organ failure. High dose vitamin C has been known to be a effective antioxidant activities against the paraquat intoxication. This study was designed to evaluate the effect of regular injection of high dose vitamin C on liver damage in paraquat poisoned rat model. Method: Fifty five rats of Sprague-Dawley strain were divided into three groups: control group, only intraperitoneally injected saline; paraquat group, single dose intraperitoneally injected paraquat(24.5%, 40 mg/kg) and every 8 hours injected saline; paraquat and vitamin C group, single dose intraperitoneally injected paraquat(24.5%, 40 mg/kg) and every 8 hours injected vitamin C(72 mg/kg). Rats were sacrificed on the 12 hours, 1st day, 2nd day, 4th day, 7th day after injection and liver tissue was obtained. H&E(Hematoxylin & Eosin) stain and Masson's trichrome stain for collagen fiber detection were undertaken. The results were observed using the microscope. Results: 1. There were no differences between control and experimental group at the 12hours after regular injection of high dose vitamin C. 2. There were significantly decreased liver damage in experimental group in the 1st day after regular injection of high dose vitamin C. 3. There were significantly increased recovery of liver damage with time in experimental group after regular injection of high dose vitamin C. Conclusion: These results suggest that regular injection of high dose vitamin C is effective in decreasing liver damage in paraquat intoxication.

• 유통과학연구
• /
• 제13권3호
• /
• pp.79-91
• /
• 2015

Purpose - First, the study identifies and analyzes consumer preferences with regard to health foods and supplements. Second, it identifies and analyzes consumer preferences with regard to the properties of Vitamin C supplements. Third, in order to provide a basic data for the development of Vitamin C supplements and to measure how consumers value the properties of different Vitamin C products, a consumer survey was conducted through the choice-based conjoint model. Based on the results, the research estimates consumers' relative product-related priorities as well as price levels and willingness to pay (WTP) for different product types, and makes suggestions regarding consumer-oriented new product development and progressive directions for the successful launch of health foods and supplements. Research design, data, and methodology - This study aims to define the attributes of health foods and supplements based on several characteristics including their natural ingredients, product price, product originality, natural ingredient content, and additional functional ingredients, and makes suggestions regarding strategic market pricing and product development for health foods and supplements according to customer attitudes and characteristics. The research used choice-based conjoint analysis methodology based on the Multinomial Logic Model and collected 94 questionnaires filled out by users of Korean Vitamin C supplements. Results - Product price is the most influential factor among the five analyzed properties. When consumers buy Vitamin C products, the relative significance level of four of the examined properties is as follows: 40.9% for product price, 23.3% for product originality, 21.9% for natural ingredient content, and 13.9% for additional functional ingredients. Vitamin C content is excluded as it is not a statistically significant factor. It is interesting that supplement manufacturers and retailers consider Vitamin C content to be very important whereas consumers do not regard it as an important factor at the time of purchase. The results for the marginal willingness to pay (MWTP) for each property of Vitamin C supplements show that consumers are willing to pay an additional 11,146 Korean won for a 50% increase in the natural ingredient content. With regard to product originality, consumers are willing to pay an additional 11,301 Korean won for products manufactured in Europe than for products manufactured in China. Moreover, consumers show a greater preference for products manufactured in Korea than in Europe. However, consumers are not willing to pay more for additional Vitamin C or additional functional ingredients added to Vitamin C products. Conclusions - According to the results of consumer research on Vitamin C supplements, which represent a popular health food supplement in Korea, most Korean health food and supplement companies are not consumer- or market-oriented when developing new products. Companies gather information from either R&D specialists or sales managers and their opinions are highly reflected in new product development. The study's results will help companies recognize the importance of understanding consumers' unmet needs in advance to develop new products in the future.

• IMMUNE NETWORK
• /
• 제9권5호
• /
• pp.147-152
• /
• 2009

Ascorbate (vitamin C) is a cofactor for a number of metabolic enzymes and is an indisputable essential vitamin C for humans. However, the potential of ascorbate as an anticancer agent has been a topic of controversy. A number of previous reports have addressed both positive aspects and limitations of ascorbate in cancer therapy. In this review, we briefly summarize the potential antitumor effects of ascorbate and its prospects for clinical use.

• Toxicological Research
• /
• 제20권3호
• /
• pp.187-193
• /
• 2004

This study aimed to determine the association of maternal oxidative stress and adverse pregnancy outcome with serum vitamin C concentration and a myeloperoxidase (MPO) genetic polymorphism during pregnancy. We investigated 450 pregnant women who visited Ewha Womans University Hospital for prenatal care during gestational weeks 24～28. During the second trimester, we measured serum vitamin C levels and urinary 8-hydroxyde-2'-deoxyguanosine (8-OHdG) and malondialdehyde (MDA) as an oxidative stress biomarker. We determined the presence of a maternal MPO polymorphism (G-to-A substitution at nucleotide 463) using a PCR-RFLP assay. We compared the level of oxidative stress and birth weight with the vitamin C concentration and the presence of the MPO polymorphism. The mean level of maternal oxidative stress tended to be higher and the birth weight lower for MPO type A/A than for types A/G and G/G. Vitamin C levels above the 75 percentiles were associated with reduced concentrations of urinary MDA and 8-OHdG but increased birth weight. Our data demonstrate that oxidative stress and neonatal birth weight are associated with the MPO genetic polymorphism, with the association modified by the maternal vita-min C levels.

• 한국가금학회지
• /
• 제29권2호
• /
• pp.135-140
• /
• 2002

비타민 C 첨가가 산란계의 생산성과 난각의 품질에 미치는 영향을 측정하기 위하여 사양실험을 실시하였다. 71주령된 산란계(ISA-Brown) 800수를 공시하여 LG 비타민 C를 각각 0, 3, 10, 50, 100 ppm, flee ascorbic acid 100 ppm, Rovimix stay C-35 100 ppm, vitamin C 50 ppm + Zn chelate (100 ppm in Zn)를 첨가한 8처리구에 5반복, 반복당 20수씩 2수용 케이지에 수용하여 난괴법으로 배치하였다. 사양실험은 5월 중순에 시작하여 4주간 실시하였으며, 이 기간 중 평균온도는 23,8$^{\circ}C$(오후 5:00 기준)이었다. 비타민 C의 첨가시 대조구에 비해 산란을, 난중 및 난각 품질의 개선효과는 없었다. 비타민 C첨가구들 중 100 ppm의 LG 비타민 C 첨가구, Rovimix stay C-35 첨가구, LG 비타민 C 50 ppm+zn chelate 첨가구의 산란율이 대조구에 비해 낮았으며, 난중은 대조구와 LG 비타민 C 100 ppm 첨가구가 가장 높았다. 50, 100 ppm LG 비타민 C 첨가와 Rovimix stay C-35첨가는 연파란율을 증가시켰다. 난각두께는 LG 비타민 C 첨가구 모두 대조구와 차이가 없었다 이상의 결과를 종합해 볼 때 외기 온도가20-$26^{\circ}C$인 환경하에서는 산란계 사료에 3-100 ppd수준의 비타민 C첨가는 산란계의 생산성 개선에 유의한 영향을 주지 못하였다.

• Journal of Nutrition and Health
• /
• 제15권3호
• /
• pp.202-211
• /
• 1982

A modification of a microbiological assay of vitamin $B_{12}$ was made and used to determine the vita­min levels during kimchi fermentation. A cyanide-buffer solution of pH 6.0 replaced the metabisufite-buffer specified in the A.O.A.C. method. The vitamin $B_{12}$ activity was decreased by blending kimchi samples for 5 minutes and retained the activity by steaming for 10 minutes before blending. The alkali hydrolysis of kimchi at pH 12.0 for 30 minutes at $121^{\circ}C$ was sufficient to destroy the vitamin $B_{12}$ and permit the detection of analogs with the same assay organism. Vitamin $B_{12}$ reached a maximum of 47ng/100g during the fermentation of kimchi ${15}\;4^{\circ}C.$ Inoculation of the kimchi with Propionibacterium shermanii (ATCC 13673) increased the vitamin production to a maximum of 102ng/100g at 1 week of fermentation. Soy flour (0.5%) or beef extract (0.05%), which were regarded as protein sources, added to the inoculated kimchi further increased the vitamin $B_{12}$ activity to 197 and 203ng/100g.

• 한국식생활문화학회지
• /
• 제36권6호
• /
• pp.571-582
• /
• 2021

This study investigates the relationship between vitamin C intake and obesity prevalence among Korean adults. Based on data of the Korean National Health and Nutrition Examination Survey (2016-2017), a total of 1,356 participants were included in this analysis. Increasing the dietary vitamin C intake resulted in a significantly decreased occurrence of BMI obesity prevalence (p for trend=0.0194) and WC obesity prevalence (p for trend=0.0452). Moreover, increasing the dietary vitamin C intake of Korean adults having a high frequency of eating breakfast resulted in significantly decreased BMI obesity prevalence (p for trend=0.0406) and WC obesity prevalence (p for trend=0.0432). Among the Korean adults who ate out frequently, decreased BMI obesity prevalence was determined with increased intakes of dietary vitamin C (p for trend=0.0193) and total vitamin C (food and dietary supplements) (p for trend=0.0429), whereas significant decrease in WC obesity prevalence was observed with increased dietary vitamin C intake (p for trend=0.0484). Our results provide conclusive evidence that consumption of dietary vitamin C is associated with obesity prevalence in Korean adults, according to their habits of eating breakfast and frequency of eating out.

• 한국식품영양학회지
• /
• 제23권1호
• /
• pp.30-38
• /
• 2010

Aflatoxin은 Aspergillus 속 곰팡이로부터 생성되며, 사람에게 있어서 간독성 및 간암을 유발하는 잠재력을 가진 곰팡이 독소이며, 지질과산화 반응은 aflatoxin $B_1$에 의한 세포 산화적 손상 시 발생하는 주요 현상 중의 하나이다. 방사선은 수술, 항암약물요법과 더불어 임상 시 중요한 치료 방법이나, 정상세포에 방사선을 조사하였을 때 반응성이 높은 활성산소와 과산화라디칼($OH^*$)을 생성하여 세포막의 불포화 지방산을 지질 과산화물로 변성시켜 세포 산화적 손상을 일으킨다. 본 연구는 곡류를 주식으로 하는 우리나라 사람들의 경우, aflatoxin $B_1$에 노출되기 쉽고 이들 중 일부는 위, 간, 담도 암과 같은 상복부 암으로 진단되어 간을 포함하는 부위에 대해 방사선 치료를 받을 수 있는 경우를 생각하여 흰쥐에게 aflatoxin $B_1$을 투여하거나 방사선과 aflatoxin $B_1$을 병합 처리하여 vitamin C가 간독성 유발요인과 연관된 간 기능 효소들의 변화와 전자현미경 실험에 의한 형태학적 관찰을 알아보고자 시행되었다. X-ray 조사는 실험기간 내 단 1회로 실험사육기간 첫 일에 조사하였고, X-ray 조사 후 vitamin C를 투여하였으며 vitamin C 투여 1시간 후 $AFB_1$을 투여하였다. Vitamin C와 AFB은 모두 복강투여로 실험 사육 첫 일부터 1회 시작하여 3일에 한번씩, 5회 반복 투여 하였으며 실험동물 사육기간은 총 15일로 하였다. GOT, ALK phatase, LDH는 유의적인 차이는 없으나 $AFB_1$을 투여한 2군에 비해 2군에 vitamin C를 투여한 3군이, 방사선과 $AFB_1$ 병합 처리한 4군에 비해 4군에 vitamin C를 투여한 5군이 각각 감소하는 경향이었다. 간 기능 효소 중 GPT는 대조군에 비해 $AFB_1$을 투여한 2군은 유의적인 차이가 없었으나 증가하였으며, 특히 2군에 비해 2군에 vitamin C를 투여한 3군은 수치가 p<0.001 수준에서 현저히 감소하였다. TEM을 이용한 간세포의 형태에서는 $AFB_1$ 단독 처리군의 세포(G2)는 세포의 핵과 핵막이 팽창되어 있으며, 소포체가 긴 막대 모양에서 원형으로 변형되어 나타나고, 미토콘드리아는 크리스테(cristae)가 분열되어 속이 빈 형태를 보여주고 있으나 여기에 vitamin C를 투여한 3군의 세포(G3)에서는 핵은 아직 약간 팽창된 모양을 하고 있으나 핵막의 모양이 거의 정상으로 되었으며, 소포체와 미토콘드리아도 거의 정상 모양을 회복하고 있다. X선 조사와 $AFB_1$ 병합 처리군인 4군의 세포(G4)는 조직의 상당한 파괴가 관찰되었으며, 여기에 vitamin C를 투여한 5군의 세포(G5)는 정상적이지는 않으나 파괴 정도가 덜 한 것을 볼 수 있었다. 이로써 $AFB_1$ 단독 투여군인 2군, 방사선과 $AFB_1$ 병합 처리한 4군에 각각 vitamin C를 혼합 투여한 3군과 5군에서 핵과 핵막 등이 정상에 가깝게 회복된 현상은 vitamin C의 항산화력에 의해 세포막 표면에 형성된 틈이나 팽창 상태가 가역적이고 반복적인 결합이 유도되어 핵과 핵막이 많이 회복된 것을 확인할 수 있었다.

• Journal of Nutrition and Health
• /
• 제55권5호
• /
• pp.523-532
• /
• 2022

비타민 C는 체내에서 중요한 항산화제 역할을 한다. 그러나 비타민 C와 다양한 대사 질환과의 관련성은 보고되었지만, 비타민 C의 섭취량, 체내 저장량, 항산화를 비롯한 체내 기능 사이의 관계를 용량-반응 관계를 연구한 것은 거의 없다. 따라서 비타민 C의 섭취 기준은 비타민 C 섭취량이 혈장 농도와 백혈구들의 포화도의 변화에 미치는 정도와, 이것이 항산화 능력과 대사성질환의 위험도에 미치는 영향을 고려하여 설정하였다. 2020 한국인 비타민 C 섭취 기준을 설정할 때 그 기준은 2015년의 설정 기준에서 변한 것은 없지만 연령별 표준체중의 변경을 반영하여 다시 계산하여 개정하였다. 2017년 이후부터 건강기능식품을 섭취하는 사람들이 증가하면서 비타민 C를 평균섭취량보다 적게 섭취하는 성인은 약 10%였으나, 청소년과 노인기에서는 평균섭취량보다 적게 섭취하는 비율이 높은 것으로 나타났다. 반면에 비타민 C 보충제의 섭취량이 증가하고 있어서 비타민 C의 섭취가 과잉인 사람들의 비율도 증가하고 있다. 흡연자나 대사질환 등 만성 질환을 가진 사람들에서 비타민 C의 필요량 증가에 대한 별도의 기준을 정하는 것이 필요하다는 의견도 있지만, 이것을 뒷받침할 만한 과학적 근거가 부족하여 기준을 설정하지는 않았다. 결과적으로 추후 한국인을 대상으로 한 흡연자, 대사질환 환자에서 비타민 C의 섭취 기준을 설정에 관련된 연구와, 보충제로 인한 비타민 C의 과잉 섭취와 다른 영양소와의 상호 작용 등에 대한 연구가 필요하겠다.