• Preventive Nutrition and Food Science
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• v.14 no.3
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• pp.260-264
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• 2009

A high-performance liquid chromatography method was applied to determine the contents of tocopherols in edible oils using a LiChrosorb DIOL HPLC column and hexane fortified with 0.1% acetic acid in an isocratic mode. The validation of the method included tests for linearity, sensitivity, accuracy, precision, and recovery. All calibration curves showed good linear regression ($r^2$>0.9995) within the tested ranges. The established method offered good precision and accuracy with overall intra-day and inter-day variations of 0.94$\sim$4.27 and 1.77$\sim$ 4.88%, respectively. The tocopherol recoveries ranged from 91.44$\sim$108.90%. Subsequently, the method was successfully applied to qualitatively and quantitatively determine the total contents of $\alpha$, $\gamma$, and $\delta$-tocopherols in 12 selected refined edible oils, showing a range of 0.92 to 188.71 mg/100 g.

• Journal of Applied Biological Chemistry
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• v.42 no.2
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• pp.66-70
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• 1999

Effects of the enhanced level of L-ascorbic acid (AA) on the water deficit-induced oxidative damage were studied in rice (Oryza sativa L.) seedlings. The seedlings sprayed with 20 to 80 mM L-galactono-${\gamma}$-lactone (GL), a putative precursor of AA, showed 2 to 5-fold higher levels of AA compared with controls. Pretreatment of the seedlings with GL prior to water stress imposition caused virtually no effect on dehydration of tissues during water deficit but substantially mitigated oxidative injury, as accessed by 2-thiobarbituric acid-reactive substances, ${\alpha}$-tocopherol, chlorophylls and ${\beta}$-carotene. Proline accumulation during water stress was also significantly lowered in the treated seedlings. In a complementary experiment, AA retarded photodegradation of ${\alpha}$-tocopherol in isolated thylakoids far more efficiently than glutathione. GL in itself did not show any noticeable reactivity toward ${\alpha}$-tocopheroxyl radical. The results demonstrate the antioxidative function of AA in rice seedlings encountering water-limited environments, suggesting a critical role of AA as a defense against oxidative stress in plants.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1096-1099
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• 2009

This study investigated change in the chemical components and antioxidant activity of ramie (Boehmeria nivea) leaves (RL) for the development of functional foods. Proximate compositions of protein, crude ash, and crude fat were 24.49, 11.41, and 4.89%, respectively. Contents of minerals of calcium (Ca), potassium (K), magnesium (Mg), and iron (Fe) were 1,874, 1,433, 362, and 16 mg/100 g, respectively. ${\alpha},\;{\beta}$, and ${\gamma}$-Tocopherol contents were 9.79, 0.18, and 1.44 mg/100 g, respectively. Linoleic and linolenic acid contents were higher than those of palmatic and stearic acid. Total phenolic and flavonoids contents showed the high level of 149 and 49 mg/g. The $IC_{50}$ values of 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl, and superoxide radical scavenging of RL extracts were 688, 424, and $596{\mu}g/mL$, respectively, while the radical scavenging values by butylated hydroxylanisole (BHA) were 92, 58, and $98{\mu}g/mL$, respectively. Thus, RL has the potential to be used as a healthy and functional food ingredient.

• 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.

• Korean journal of food and cookery science
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• v.14 no.4
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• pp.375-379
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• 1998

Some Physico-chemical properties of korean red pepper seed oil were evaluated to find available method to utilize red pepper seeds used as useful cooking oil resources. Samples of red pepper seeds used as oil meterials were native, improved species and they were named such as NS (native spicies dried under sunlight), IS (improved spicies dried under sunlight), NF (native spicies dried by heating), and IF(improved spicies dried by heating), respectively. Moisture, ash, crude protein and crude fat contents of all red pepper seeds were 6.6%∼7.7%, 3.3∼3.5%, 18.25∼19.4% and 26.8∼27.5% in all samples, showing the specially high crude fat and crude protein content in NS. Capsaicin contents in crude red pepper seed oils were shown from 0.06 to 0.08% but after refining process, capsaicin contents were mostly tossed as 0∼0.006%. The types of tocopherol found in crude and refined red pepper seed oils were ${\gamma}$-, ${\alpha}$-, $\delta$-analogues, the amount of total tocopherol in IF was 2.10 mg/g oil which were the highest value of all red pepper seeds. In all red pepper seeds oils main fatty acids were linoleic acid (68∼70%), palmitic acid (14∼16%), oleic acid (10∼11%), and linolenic acid were extemely small amounts. The specific gravity (SG) 0.916∼0.919, refractive index (RI) 1.4724, acid value (AV) 0.26∼0.36, peroxide value (POV) 0.73∼1.19 and Iodine value (IV) 134.35∼134.92 were measured in all red pepper seed oils.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1259-1266
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• 1998

To clarify the values and varieties of the buckwheats as a dietary source of nutritional and functional components, thirteen different samples of buckwheat were analyzed for this investigation. Six developed seeds were given by RDA, Korea or RDA branch of Kangwondo, and seven land race seeds were collected from a farmhouse. Amino acid analysis showed that glutamate, arginine and asparagine were major amino acids, whereas tryptophan, methionine and cysteine were minor ones of buckwheat. In addition, tryptophan content of buckwheat cultivars from Korea was 195 mg% on average. The content of rutin tended to be higher in developed cultivars than land races. On the other hand, the contents of phytic acid in buckwheats were in the range of 7.0 to 13.6 mg/g. In the tocopherol homologues of the buckwheats analyzed by HPLC, mean ${\gamma}-tocopherol$ contents were 6.16 mg/100 g with the actual range of $4.67{\sim}8.58\;mg/100g$, whereas ${\beta}-form$ was very low or zero. There were a big variations in the iron content of the buckwheats of the minerals. SDS-PAGE showed that total proteins from buckwheats exhibited a relatively similar electrophoretic patterns on the whole. The results show that CV Suwon 1 has good quality, judged from the distribution of the components of buckwheats analyzed.

• Nutrition Research and Practice
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• v.10 no.1
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• pp.33-41
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• 2016

BACKGROUND/OBJECTIVES: Diabetes mellitus (DM) is a major chronic disease which increases global health problems. Diabetes-induced renal damage is associated with inflammation and fibrosis. Alpha (AT) and gamma-tocopherols (GT) have shown antioxidant and anti-inflammatory effects in inflammation-mediated injuries. The primary aim of this study was to investigate effects of AT and GT supplementations on hyperglycemia induced acute kidney inflammation in alloxan induced diabetic mice with different levels of fasting blood glucose (FBG). MATERIALS/METHODS: Diabetes was induced by injection of alloxan monohydrate (150 mg/kg, i.p) in ICR mice (5.5-week-old, male) and mice were subdivided according to their FBG levels and treated with different diets for 2 weeks; CON: non-diabetic mice, m-DMC: diabetic control mice with mild FBG levels (250 mg/dl ${\leq}$ FBG ${\leq}$ 450 mg/dl), m-AT: m-DM mice fed AT supplementation (35 mg/kg diet), m-GT: m-DM mice with GT supplementation (35 mg/kg diet), s-DMC: diabetic control mice with severe FBG levels (450 mg/dl < FBG), s-AT: s-DM mice with AT supplementation, s-GT: s-DM mice with GT supplementation. RESULTS: Both AT and GT supplementations showed similar beneficial effects on $NF{\kappa}B$ associated inflammatory response (phosphorylated inhibitory kappa B-${\alpha}$, interleukin-$1{\beta}$, C-reactive protein, monocyte chemotactic protein-1) and pre-fibrosis (tumor growth factor ${\beta}$-1 and protein kinase C-II) as well as an antioxidant emzyme, heme oxygenase-1 (HO-1) in diabetic mice. On the other hands, AT and GT showed different beneficial effects on kidney weight, FBG, and oxidative stress associated makers (malondialdehyde, glutathione peroxidase, and catalase) except HO-1. In particular, GT significantly preserved kidney weight in m-DM and improved FBG levels in s-DM and malondialdehyde and catalase in m- and s-DM, while AT significantly attenuated FBG levels in m-DM and improved glutathione peroxidase in m- and s-DM. CONCLUSIONS: the results suggest that AT and GT with similarities and differences would be considered as beneficial nutrients to modulate hyperglycemia induced acute renal inflammation. Further research with careful approach is needed to confirm beneficial effects of tocopherols in diabetes with different FBG levels for clinical applications.

• Journal of agriculture & life science
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• v.45 no.4
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• pp.121-133
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• 2011

Effects of roasting on vitamin E content, color, microstructure and moisture of peanuts, and vitamin E content in peanut oils prepared from the roasted peanuts were investigated. Runner-type peanuts were roasted at 140, 150, and $160^{\circ}C$ for 10-20 min. As roasting temperature and time increased, the CIELAB $L^*$ value of peanuts decreased while $a^*$ and $b^*$ values increased, resulting in formation of the golden brown color of roasted peanuts. Moisture ratio (M/Mo) and color $b^*$ value of peanuts roasted at 140 to $160^{\circ}C$ showed a correlation of $b^*=21.61\;(M/Mo)^2-40.62\;(M/Mo)+34.12$ ($R^2=0.9123$). Overall changes in the tocopherol contents of peanuts and peanut oils were significantly affected by roasting temperature and time (p<0.05). Roasting at $140^{\circ}C$ caused a slight increase in the levels of tocopherols of peanuts over roasting time up to 20 min (p<0.05). There was no significant change in the tocopherol levels of peanuts during roasting at $150^{\circ}C$ for 20 min (p>0.05). At $160^{\circ}C$, the levels of tocopherols significantly decreased during the initial 10 min of roasting (p<0.05) while there was no extended loss after 10 min, resulting in about 5, 12, 20, and 10% losses of ${\alpha}$-, ${\beta}$-, ${\gamma}$- and ${\delta}$-T, respectively. After 20 min, total tocopherols decreased by 18%. However, tocopherol contents of pressed peanut oils significantly decreased at all roasting temperatures (p<0.05). After roasting peanuts at $160^{\circ}C$ for 20 min, about 84% of initial ${\alpha}$-T in peanut oils was retained. ${\alpha}$-T was the most stable to roasting while ${\gamma}$-T was the least. Swollen epidermal cells on the inner surface and broken cell walls of parenchyma tissue of peanut cotyledon were observed in peanuts after roasting at $160^{\circ}C$ for 15 min. Severe changes in microstructure of peanut by roasting would contribute to vitamin E stability because of exposure of oil droplets in peanuts to oxygen.

• Journal of the Korean Applied Science and Technology
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• v.33 no.3
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• pp.560-567
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• 2016

Acid-activated clays (SUPER-DC, DC-A3, and P1) are used for the bleaching of cold-pressed rapeseed oil. In this study we tested the bleaching performance of cold-pressed rapeseed oil according to the different reaction time (20, 40, 60, 80 min) and temperature (40, 80, $120^{\circ}C$). Oil color (lightness, redness, yellowness), pigments (chlorophyll A and carotenoid content) and quality properties (fatty acid composition, tocopherols (${\alpha}$, ${\beta}$, ${\gamma}$, ${\delta}$), and plant sterols (${\beta}$-sitosterol, campesterol, stigmasterol) content) were analyzed. The results showed that bleaching of cold-pressed rapeseed oil with 2% acid-activated clays at $40^{\circ}C$ for 20 min, brightness (L) increased, but redness (a) and yellowness (b) decreased. Bleaching of cold-pressed rapeseed oil with 2% DC-SUPER at $40^{\circ}C$ removed chlorophyll A and carotenoids pigments significantly. In addition, about 50% of total tocopherol content in cold-pressed rapeseed oil was reduced by bleaching. Originally total tocopherol content was 46.62mg/100g in cold-pressed rapeseed oil. But after bleaching, total tocopherol content was 12.67mg/100g (20 min bleaching), 15.31mg/100g (40 min bleaching), and 13.56mg/100g (60 min bleaching). However plant sterols content in cold-pressed rapeseed oil remained unchanged by bleaching. Overall, acid-activated clays were useful for the bleaching of pigmented rapeseed oil.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.11
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• pp.4601-4607
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• 2014

Red rice contains pharmacological substances including phenolics, oryzanol, tocotrienol and tocopherol. Recently, red rice extract has been employed as a source of antioxidants for inhibition of tumor growth. This study was carried out to evaluate the anti-invasion effects of red rice extract fractions on cancer cells. It was found that at $100{\mu}g/ml$ of crude ethanolic extract (CEE), hexane fraction (Hex) and dichloromethane fraction (DCM) could reduce HT1080 and MDA-MB-231 cancer cell invasion. Hex and DCM revealed higher potency levels than CEE, whereas an ethyl acetate fraction (EtOAc) had no effect. Gelatin zymography revealed that Hex decreased the secretion and activity of matrix metalloproteinase-2 and -9 (MMP-2 and-9). In contrast, the DCM fraction exhibited slightly effect on MMPs secretion and had no effect on MMPs activity. Collagenase activity was significantly inhibited by the Hex and DCM fractions. High amounts of ${\gamma}$-oryzanol and ${\gamma}$-tocotrienol were found in the Hex and DCM fractions and demonstrated an anti-invasion property. On the other hand, proanthocyanidin was detected only in the CEE fraction and reduced MDA-MB-231 cells invasion property. These observations suggest that proanthocyanidin, ${\gamma}$-oryzanol and ${\gamma}$-tocotrienol in the red rice fractions might be responsible for the anti invasion activity. The red rice extract may have a potential to serve as a food-derived chemotherapeutic agent for cancer patients.