• 한국식품위생안전성학회지
• /
• 제20권3호
• /
• pp.141-146
• /
• 2005

역상 컬럼을 이용하여 건강기능식품 중 클로렐라 및 스피루리나제품에 함유되어 있는 엽록소 a, b,페오포르바이드 a 및 $\beta$-카로틴의 HPLC동시분석법을 확립하였으며, 첨가농도 $50\;\mug/ml$에서 엽록소 a, b, 페오포르바이드 a 및 $\beta$-카로틴에 대한 회수율시험결과, 각각 2.8, 6.0, 10.6 및 $10.4\%$의 상대표준편차와 70.3, 71.6, 60.1 및 $90.5\%$의 회수율을 각각 나타냈다. 이때 검출한계는 $0.1\sim1.0\;\mug/ml$, 정량한계는 $0.2\sim2.0\;\mug/ml$이었으며 검량선 상관계수도 0.995 이상의 직선성을 보여주었다. 국내유통 클로렐라 및 스피루리나제품에 대한 엽록소 a, b,페오포르바이드 a및 $\beta$-카로틴의 함유량을 분석한 결과 엽록소 a $121.g\sim543$, 엽록소 b $0.6\sim160.0$, 페오포르바이드 a 및 P-카로틴 $383.6\sim1713.7mg/ml$ 수준으로 나타났다. 엽록소 b의 함유량은 클로렐라제품에서 평균 374.0 mg/100 g 으로 스피루리나제품의 평균 10.5 mg/100 g 보다 30배 이상 함유하고 있는 것으로 확인되었다. 그러나 $\beta$-카로틴의 함유량은 스피루리나제품이 평균 1335.4 mg/100 g 로 클로렐라제품의 평균 495.0 mg/100 g 보다 평균 함유량에서 2.7배 높은 것으로 나타났다. 국내 건강기능식품공전 중 클로렐라 및 스피루리나제품의 엽록소 a b, 및 페오포르바이드 항목의 규격검사를 본 연구의 동시분석법으로 개정함으로써 각 성분 함량의 정량, 분석시간의 단축 및 비용절감 둥 시험방법을 크게 개선할 수 있을 것으로 기대된다.

• 한국식품과학회지
• /
• 제33권1호
• /
• pp.33-39
• /
• 2001

이온쌍고속액체크로마토그래피를 이용하여 현재 우리나라에서 식품에 사용이 허용된 타르색소 8종과 일본등 외국에서는 허용되어 있으나 우리나라에서 허용되어 있지 않은 11종 등 총 19종의 동시 및 계통분석법을 확립하였다. HPLC에 사용한 컬럼은 Symmetry $C_18$, 이동상은 0.01 M TBA-Br이 함유된 0.025 M 초산암모늄용액-아세토니트릴-메탄올(65 : 25 : 10)과 0.01 M TBA-Br이 함유된 0.025 M 초산암모늄용액-아세토니트릴-메탄올(40 : 50 : 10)를 구배용매조성법(gradient mode)으로 사용하였다. 자외선 검출기의 파장은 동시분석의 경우 254 nm, 계통분석은 황색계통 420 nm, 적색계통 520 nm 그리고 청색 및 녹색계통은 620 nm로 설정하였다. 이때 색소들의 검출한계는 적색계통이 $0.05\;{\mu}g/g$, 황색계통은 $0.03\;{\mu}g/g$, 청색 및 녹색계통은 $0.01\;{\mu}g/g$이었다. Sep-pak $C_18$을 이용한 색소의 정제 방법은 혼합색소표준용액의 pH를 $5{\sim}6$으로 조정하고 0.1% TBA-Br을 가하여 색소를 보유시킨 다음 0.1% 염산-메탄올로 색소를 용출하여 HPLC로 분석하였다. 19종의 타르색소를 동시분석하는데 35분이, 계통분석시에는 18분 정도가 소요되었고 두 경우 모두 양호한 분리를 보였다.

• Journal of Biosystems Engineering
• /
• 제36권6호
• /
• pp.444-452
• /
• 2011

In this study the characteristics of natural ventilation of Venlo-type greenhouse with continuous roof vents were analyzed using commercial computational fluid dynamics (CFD) code. Developed CFD simulation model was verified by comparison with experimental data. Simulation errors were 1.9-46.0% for air velocity and 1.7-11.2% for air temperature at each measurement point. CFD simulations were conducted to estimate the effect of roof vents opening direction, opening angle, outside wind velocity and wind directions on ventilation rate and climate condition in greenhouse. The results of this study showed that ventilation rate of the present greenhouse was increased linearly in proportion to the increase of roof vent opening angle and outside wind velocity over 2.0 m/s. According to the analysis on the effects of different roof vent opening direction, simultaneous opening of wind and leeward vents showed the highest ventilation rate and lowest mean temperature in greenhouse.

• 생약학회지
• /
• 제31권4호
• /
• pp.455-458
• /
• 2000

Research on pesticide residues as endocrine disruptors in natural medicines was initiated by Korea Food & Drug Administration this year. We determined the presence and levels of certain pesticides in selected natural medicines. The natural medicines collected this year are Glycyrrhiza Root, Cinnamon Bark, Pueraria Root, Polygonatum Rhizome, Jujube, Schizandra Fruit, Lycium Fruit, Liriope Tuber, Eucommia Bark, Peony Root, Korean Angelica, Dioscorea Rhizome, Cnidium Rhizome, Cassia Seed, Platycodon Root, Comus Fruit, Mentha Herb, Epimedium Herb, Bupleurum Root, and Ginger, which have no data for pesticide residues and 192 samples of them were circulated in Korea, 28 samples were circulated in China. In order to analyze many pesticides in large number of samples we used simultaneous multi-residue analysis of pesticides by GC-ECD, which was followed by GC-MSD analysis to confirm the identity of the detected pesticide in each sample.

• 약학회지
• /
• 제31권2호
• /
• pp.82-91
• /
• 1987

The effect of neurotoxic compound 6-hydroxydopamine (6-OHDA) on the change in blood pressure and contractile response of Vas deference by centrally acting agents has been studied in normal and DOCA-salt induced hypertensive rats. The treatment of neonatal rats with 6-OHDA (2$\times$100mg, 250mg Kg$^{-1}$s.c) significantly inhibited the antihypertensive and relaxant effects of Vas deference of clonidine(100$\mu\textrm{g}$ Kg$^{-1}$iv.). The simultaneous administration of desipramine with clonidine into neonatal rats decreased the antihypertensive response of clonidine although treated did not affect the relaxative response of Vas deference. Furthermore, the antihypertensive and relaxant responses of clonidine were reduced by the neonatal rats with 6-OHDA regardless of the administration of desipramine. When neonatal rats were administered with 6-OHDA, the development of DOCA-salt hypertension was prevented. These results suggest that 6-OHDA, clonidine and desipramine hada significant effect on the development and the inhibition of central hypertension mediating the central adrenergic neuron due to their affinity to the central nervous system.

• 대한약리학회지
• /
• 제1권1호
• /
• pp.7-16
• /
• 1965

Glycyrrhizin, an active constituent of Glycyrrhiza, was chemically extracted and its hypocholesterolemic activities were studied in rats. Following were the results: 1. The Sprague Dowley rats fed with the standard diet were divided into 4 groups, $50{\sim}60$ in each, and glycyrrhizin was given in doses of 0 (control), 0.5, 1.0 and 2.0mg per 100gm body weight daily for 10, 20, 30, and 60 days. Glycyrrhizin showed more or less the hypocholesterolemic activities in all animals. All of the animal groups to which 1. 0mg and 2.0mg of glycyrrhizin were given died before 60 days, while no mortality cases was noted in the group to which 0.5mg of glycyrrhizin was given. 2. Cholesterol administration induced hypercholesterolemia in all experimental animals, however, simultaneous administration of cholesterol with 0.5mg of glycyrrhizin suppressed the rise of the total serum cholesterol levels. The former group did not survive until 56 days, while the latter did. 3. Glycyrrhizin also Suppressed the cholesterol biosynthesis and incorporation of cholesterol in the liver tissues. 4. Glycyrrhizin induced the increase of the fecal excretion of the sterol compounds.

• 대한약학회:학술대회논문집
• /
• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
• /
• pp.396.1-396.1
• /
• 2002

HPTLC(High Performance Thin Layer Choromatography) method was developed for rapid and precise analysis of Sildenafil and modified Sildenafils(Vardenafil. Homosildenafil, Tadanafil). Chromatographic conditions were Optimized for simultaneous analysis of them and each specific UV spectra were obtained. The calibration curve of Sildenafil and modified Sildenafils had a linearity in the range of 1.0 ~ 56.5 $\mu$/ml at 254nm. The Limit of Detection(LOD) and the limit of Quantification(LOQ) of Sildenafil and modified Sildenafils were 0.8$\mu$/ml and 1.0$\mu$g/ml. (omitted)

• 대한약학회:학술대회논문집
• /
• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
• /
• pp.397.2-397.2
• /
• 2002

Sildenafil citrate(SC. Viagra(equation omitted)) is the oral treatment for erectile dysfunction. Vardenafil hydrochloride. tadalafil and modified sildenafil have anti-impotent effect and have possibility to be used illegally. The aim of this study was to set up simultaneous determination method of anti-impotent drugs using TLC and HPLC. The anti-impotent drugs were extracted with 50% methanol and then diluted with mobile phase for HPLC and also extracted with developing solvents as sample solutions for TLC. (omitted)

• 대한약학회:학술대회논문집
• /
• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
• /
• pp.403.1-403.1
• /
• 2002

Combination of two or more preservatives are commonly used in cosmetic creams to prevent alteration and degradation of the product formulation. but preservatives are one of the main causes of allergic contact dermatitis from the use of cosmetics. (omitted)

• Asia Marketing Journal
• /
• 제21권3호
• /
• pp.1-20
• /
• 2019

The present study investigates how consumers' construal level affects their variety seeking behavior when choosing multiple items simultaneously. Especially the authors focus on the perceptual level at which variety seeking takes place and propose that variety seeking can take place not only at brand level but also at category or subcategory level. Categorical variety seeking refers to diversification of one's choices over multiple brands not within the same category but across multiple categories. Building on construal level theory, the authors expected that people engaging in higher-level construals tend to subcategorize the choice set and distribute their choices across more subcategories and designed four experiments to test the related hypotheses. The experimental results showed that consumers' construal level can affect the level at which variety seeking takes place and those with higher construal level tend to choose options seemingly more dissimilar to each other.