• Title/Summary/Keyword: $D_{50}$

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Antioxidant and Tyrosinase Inhibitory Activities of Dicaffeoylquinic Acid Derivatives Isolated from Gnaphalium Affine D. DON (떡쑥 추출물로부터 분리된 Dicaffeoylquinic Acid 유도체들의 항산화 및 타이로시네이즈 저해 활성)

  • Im, Na Ri;Kim, Hae Soo;Ha, Ji Hoon;Noh, Geun Young;Park, Soo Nam
    • Applied Chemistry for Engineering
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    • v.26 no.4
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    • pp.470-476
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    • 2015
  • In this study, three dicaffeoylquinic acids (DCQAs) isolated from Gnaphalium affine D. DON. extracts were structurally identified and evaluated for their antioxidant activities, cellular protective effects, and tyrosinase inhibitory activities. The ethyl acetate fraction of G. affine was chromatographed, which yielded 3 DCQA derivatives of 1-3 : 3,5-dicaffoylquinic acid (3,5-DCQA, 1), 4,5-dicaffeoylquinic acid (4,5-DCQA, 2), 1,5-dicaffoylquinic acid (1,5-DCQA, 3). The structure of each compounds was determined using $^1H$ NMR and MS analyses. Compounds of 1-3 showed strong free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activities ($FSC_{50}=3.70$, 5.80, and $5.50{\mu}M$, respectively) compared to those of a commonly used lipophilic antioxidant, (+)-${\alpha}$-tocopherol ($21.90{\mu}M$). Cellular protective effects of 1-3 compounds on the $^1O_2$ sensitized photohemolysis of human erythrocytes were similar to (+)-${\alpha}$-tocopherol. 1-3 compounds also exhibited higher tyrosinase inhibitory effects ($IC_{50}=0.15$, 0.16, and 0.13 mM) compared to arbutin (0.33 mM), known as a skin-whitening agent. These results indicate that three DCQA derivatives may be applied as an antioxidant and a skin whitening agent in food or cosmetic industries.

Effects of Rice Added with Mulberry Leaves and Fruit on Blood Glucose, Body Fat and Serum Lipid Levels in Rats (뽕잎오디쌀이 흰쥐의 혈당농도와 체지방 및 혈청지질 분획에 미치는 영향)

  • Han, Chan-Kyu;Kim, Sung-Soo;Choi, Sang-Yoon;Park, Ju-Hun;Lee, Bog-Hieu
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.38 no.10
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    • pp.1336-1341
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    • 2009
  • This study was performed to investigate the effects of rice added with mulberry leaves and fruit on blood glucose, body fat and serum lipid levels in Sprague-Dawley male rats for 4 weeks. Mulberry rice diet was prepared with mixture of 50% of purified AIN-diet and 50% of formulated rice consisting of soybean, barley, polished rice, black rice, uncleaned rice bud, mulberry leaves and fruit. The experimental animals were fed the mulberry rice diet (group A) and the purified AIN-diet (group B, diabetic control) for 4 weeks in rats injected with streptozotocin. In terms of observing hypolipidemic effect of mulberry rice, rats were fed either high-fat diet (13% fat) with additional lard, corn oil, cholesterol to AIN-diet (group C, control) or mulberry rice diet mixed with high fat diet (group D) for 4 weeks. Blood glucose level at the 4th week of group A had increased 5 mg/dL compared with that of day 0, while group B increased 51 mg/dL. However, the glucose levels of the groups A and B at the final day were 156 mg/dL (12.4% decrease compared with B) and 178 mg/dL, respectively. As for hypolipidemic effect, weight gain and body fat were 8% lower in the group D and serum triglyceride level also 19% lower in the group D compared with those of group C (p<0.05).

Application of Response Surface Analysis for Predicting Moisture Content of Binary Mixture (다중 회귀분석에 의한 이상혼합물(二相混合物)의 수분함량 예측)

  • Yoon, Heeny H.N.;Kim, H.;Shin, Y.D.;Yoo, M.Y.
    • Korean Journal of Food Science and Technology
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    • v.18 no.2
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    • pp.82-87
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    • 1986
  • The water sorption isotherms of binary mixtures, prepared by corn starch and isolated soybean protein (ISP) or casein, were measured and analyzed. Simple equations to predict moisture content from knowledge of composition and water activity of the mixture were derived by applying Response Surface Analysis. Comparison between predicted and experimental moisture content for 13 combinations of corn starch-lSP mixture at the range of $a_w$ 0.25-0.87 resulted in a maximum error of only 6.06% and an absolute mean error of 2.60%, and for the mixture of corn starch-casein the error was -4.39% and 2.12%, respectively. The agreement between experimental and predicted water sorption isotherms was shown to be 'highly acceptable' for the binary mixtures of 50% corn starch-50% ISP and 50% corn starch -50% casein.

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The Burst Effect Analysis of 2.5 Gb/s TDM-PON Systems Using a SOA Link Extender (반도체광증폭기로 전송거리 확장된 2.5 Gb/s TDM-PON에서 버스트 효과에 의한 신호왜곡 분석)

  • Choi, Bo-Hun;Lee, Sang Soo
    • Korean Journal of Optics and Photonics
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    • v.23 no.1
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    • pp.6-11
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    • 2012
  • A bidirectional TDM-PON link to support 2.5 Gb/s upstream signals of 256 ONUs was considered for an extended transmission distance of 50 km. The power budget of the link was 58 dB for the upstream signal and a SOA was applied as a link extender which had a 25 dB gain. Receiver sensitivity of the upstream signal was -25 dBm for -30 dBm input power to the SOA. When the input power was -10 dBm, pulse overshooting caused by gain transient of the SOA was maximum at 45% and the signal performance degradation gave a power penalty of 1.55 dB for $10^{-12}$ BER. However the penalties diminished rapidly and became negligible as the input power went below -15 dBm. So this input power dynamic range of up to -15 dBm means that it is not positively necessary to use gain control methods for the next generation TDM-PON systems.

Association between vitamin D intake and bone mineral density in Koreans aged ≥ 50 years: analysis of the 2009 Korea National Health and Nutrition Examination Survey using a newly established vitamin D database

  • Yoo, Kyoung-Ok;Kim, Mi-Ja;Ly, Sun Yung
    • Nutrition Research and Practice
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    • v.13 no.2
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    • pp.115-125
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    • 2019
  • BACKGROUND/OBJECTIVES: Vitamin D plays an important role in skeletal growth and maintenance and in the prevention of various diseases. We investigated the relationship between vitamin D intake and bone mineral density (BMD) in Korean adults aged ${\geq}50$ years using the 2009 Korea National Health and Nutrition Examination Survey data. SUBJECTS/METHODS: This study was conducted in 1,808 subjects aged ${\geq}50$ years with BMD data in Korea. Dietary vitamin D levels were assessed by the 24-hour recall method. BMD was measured using dual-energy X-ray absorptiometry. We investigated general characteristics and the association between these characteristics, vitamin D status, and BMD. RESULTS: Vitamin D intake was significantly lower in the osteoporosis group among women (P < 0.05). Among all subjects, the higher the serum 25(OH)D concentration, the higher the whole-body total BMD (WBT-BMD), femoral total hip BMD, and femoral neck BMD (P < 0.01). In the serum vitamin D-deficient group of both the total population and women, serum 25(OH)D concentration was associated with WBT-BMD (P < 0.05). Among women with a calcium intake < 537.74 mg/day, BMD of those with a vitamin D intake > $2.51{\mu}g/day$ (average intake of women) was higher than that of women with a vitamin D intake ${\leq}2.51{\mu}g/day$ (P < 0.001). CONCLUSIONS: Korean adults should increase their BMD by increasing serum 25(OH)D concentration. Furthermore, increasing vitamin D intake could improve BMD, especially in Korean women who consume less calcium than the estimated average requirement.

Toxicokinetics of CJ-11555: Gender Difference and Minimum Accumulation

  • Kim, Il-Hwan;Noh, Hyun-Jung;Park, Jae-Mook;Kim, Deog-Yeor;Park, Jie-Eun;Lee, Sung-Hak;Kim, Taek-Rho;Kim, Jin-Wan;Kim, Young-Hoon
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.243.2-244
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    • 2003
  • Purpose: This study evaluated gender differences and extents of accumulation on chronic dose of CJ-1l555 using rats. Method: 0, 10, 50 and 200 mg/kg/day of CJ-11555 (0.5% CMC) were orally administered to rats for 28 days and observed toxicokinetic parameters. Plasma concentrations were analyzed by LC-MS/MS Result: Exposure to CJ-11555 increased with the increase in dose level for both sexes. Mean concentrations at 10 and 50 mg/kg/day were generally similar an Days 1 and 28, but were generally highter on Day 28 than on Day 1 at 200 mg/kg/day. (omitted)

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Prediction of the Noise Levels for a Plant (공장 소음도 예측)

  • 윤세철;김태구;오종민
    • Journal of the Korean Society of Safety
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    • v.15 no.3
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    • pp.88-95
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    • 2000
  • The level of noise produced by machinery and its arrangement insides a factory is indicated to be a maximum of 96.1 dB(A). The maximum level of noise from a commoner's house outside the factory is shown to be 62.9 dB(A), which exceeds 60 dB(A), the permitted limit of noise level in a time period of day. us study has predicted the level of noise reduction according to a step by step prevention plan by considering the characteristics of the causes of noise, the permitted limit of noise levels, problems and economical efficiency attendant upon the noise prevention measures. Establishing target levels of noise each of the three steps of the noise prevention plan. The predicted level of noise at the place of a commoner's house in accordance with the first step is 50.0 - 59.0 dB(A), and can satisfy the permitted limit of noise in a time period of the day. In taking prevention measures for the second step, the noise level is 50.7 - 53.6 dB(A) which is less than 55 dB(A) in a time period of the evening, the permitted limit of noise in a time period of night., and it can meet 47.4 - 50.3 dB(A) in the third step.

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The Physical Properties of Non-Circular Shaper(+Type) DTY Yarn (이형단면(+Type) DTY사의 물성변화)

  • Park, Myung-Soo
    • Fashion & Textile Research Journal
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    • v.13 no.1
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    • pp.130-134
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    • 2011
  • In the study, the physical properties of the raw sample, non-circular(+ type) DTY yarn(50d level) with absorption and quick-dry function, were examined before and after being twisted(1000T/M). The results are as follows: The shrinkage of non-cricular(+type) DTY yarn(50d/36f) at $180^{\circ}$ was about 6-7% with twisted samples, but the samples without twisting went 8 to 10%. The elongation of the non-twisted and twisted samples at $180^{\circ}$ and 30-minute treatment time reached 50% and 40%, respectively. The tenacity of non-cricular(+type) DTY yarn(50d/36f) was affected less by treatment temperature in the twisted condition.

Proton Beam Sensitivity of Basidiospore and Mycelium in Pleurotus ostreatus (느타리버섯 포자와 균사체의 양성자 빔 조사에 대한 민감도)

  • Kwon, Hye-Jin;Kong, Won-Sik
    • The Korean Journal of Mycology
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    • v.34 no.1
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    • pp.34-38
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    • 2006
  • To assess the effects of proton beam on radiation sensitivity of the basidiospore and mycelium of oyster mushroom (Pleurotus ostreatus), the $D_{10}$ values and $L_{50}$ (lethal 50%) values were analysed. By the proton beam radiation, the survival rate and germination rates increased at the dose of $10\;Gy{\sim}100\;Gy$ and then decreased significantly over 500 Gy. $L_{50}$ values of basidiospore and mycelium of Pleurotus ostreatus were over 500 Gy and 400 Gy, respectively. $D_{10}$ values were calculated from linear regression formulae ($D_{10}\;=\;-1/slope(b)$, y = a + bx) as 750 Gy and 1,250 Gy, respectively. Based on our experiment, the optimum dose of proton beam as a mutation source would be between from 500 Gy to 750 Gy for basidiospores and from 400 Gy to 1000 Gy for mycelium of oyster mushroom.

Effects of Ensiling Period and Bacterial Inoculants on Chemical Compositions and Fermentation Characteristics of Rye Silage

  • Lee, Seong Shin;Joo, Young Ho;Choi, Jeong Seok;Jeong, Seung Min;Paradhipta, Dimas Hand Vidya;Noh, Hyeon Tak;Han, Ouk Kyu;Kim, Sam Churl
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.41 no.4
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    • pp.259-266
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    • 2021
  • The present study was aimed to estimate the effect of ensiling period and bacterial inoculants on chemical compositions and fermentation characteristics on rye silage harvested at delayed stage. Rye (Secale cereale L.) was harvested after 20 days of heading stage (29.4% dry matter, DM). The harvested rye forage was applied with different inoculants following: applications of distilled water (CON), Lactobacillus brevis (LBB), Leuconostoc holzapfelii (LCH), or mixture of LBB and LCH at 1:1 ratio (MIX). Each forage was ensiled into 20 L mini bucket silo (5 kg) for 50 (E50D) and 100 (E100D) days in triplicates. The E50D silages had higher in vitro digestibilities of DM (IVDMD, p<0.001) and neutral detergent fiber (IVNDFD, p=0.013), and lactate (p=0.009), and acetate (p=0.011) than those of E100D, but lower pH, lactic acid bacteria (LAB), and yeast. By inoculant application, LCH had highest IVDMD and IVNDFD (p<0.05), while MIX had highest lactate and lowest pH (p<0.05). The CON and LCH in E50D had highest LAB and yeast (p<0.05), whereas LBB in E100D had lowest (p<0.05). Therefore, this study concluded that LCH application improved the nutrient digesbility (IVDMD and IVNDFD) of lignified rye silage, and longer ensiling period for 100 days enhanced the fermentation characteristics of silage compared to ensiling for 50 days.