• Title/Summary/Keyword: pH ranges

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The analysis of endocrine distruptors in commercial cosmetics (유통 화장품 중 내분비계 장애물질 탐색 및 규명에 관한 연구)

  • Koo, Heesoo;Na, Youngran;Lee, Seungju;Min, Sangkee;Kang, Jungmi;Jin, Sung Hyun
    • Analytical Science and Technology
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    • v.28 no.3
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    • pp.212-220
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    • 2015
  • This study aims to identify the characteristics of phthalates (DMP, DEP, DBP, DEHA, BBP, DEHP, and DNOP) and heavy metals such as lead (Pb), cadmium (Cd), and mercury (Hg) in cosmetics and their containers. Phthalates and heavy metals may be endocrine distruptors. Sixty-five cosmetics were purchased from online and offline stores in Busan. This study developed a simultaneous method for the analysis of phthalates by GC-FID. The results showed that among the 65 cosmetics, DBP, DEHP, and DEP were detected at 20.0%, 7.7%, 1.5%, respectively. The amounts of DBP and DEHP detected in 18 samples were less than 100 μg/g, which satisfies the Regulations of Cosmetic Safety Standards in Korea. In order to detect phthalates in cosmetic containers, a dissolution test was conducted by extracting solutions, such as water, n-heptane, 20% ethanol, 50% ethanol and 4% acetic acid, which were prepared with different levels of pH, alcohol content, and fat content following the Korea Standards and Specifications for Utensils, Containers, and Packaging. The results showed that DMP, DBP, DEHA, BBP, DEHP, and DNOP were not detected, DEP was detected in plastics such as PE, PP, and others, when a 50% alcohol solvent was used. Phthalates may not be detected in cosmetic containers if they are not packaged with the above 20% alcohol constituent. We also analyzed the concentration of heavy metals, such as Pb, Cd, and Hg, by using ICP-OES and a mercury analyzer. The ranges of concentration were ND~2.71 μg/g for Pb, ND~0.31 μg/g for Cd, and ND~0.01 μg/g for Hg, which are below the regulated level.

HPLC Method for Simultaneous Quantitative Detection of Quercetin and Curcuminoids in Traditional Chinese Medicines

  • Ang, Lee Fung;Yam, Mun Fei;Fung, Yvonne Tan Tze;Kiang, Peh Kok;Darwin, Yusrida
    • Journal of Pharmacopuncture
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    • v.17 no.4
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    • pp.36-49
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    • 2014
  • Objectives: Quercetin and curcuminoids are important bioactive compounds found in many herbs. Previously reported high performance liquid chromatography ultraviolet (HPLC-UV) methods for the detection of quercetin and curcuminoids have several disadvantages, including unsatisfactory separation times and lack of validation according the standard guidelines of the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use. Methods: A rapid, specific, reversed phase, HPLC-UV method with an isocratic elution of acetonitrile and 2% v/v acetic acid (40% : 60% v/v) (pH 2.6) at a flow rate of 1.3 mL/minutes, a column temperature of $35^{\circ}C$, and ultraviolet (UV) detection at 370 nm was developed. The method was validated and applied to the quantification of different types of market available Chinese medicine extracts, pills and tablets. Results: The method allowed simultaneous determination of quercetin, bisdemethoxycurcumin, demethoxycurcumin and curcumin in the concentration ranges of $0.00488-200{\mu}g/mL$, $0.625-320{\mu}g/mL$, $0.07813-320{\mu}g/mL$ and $0.03906-320{\mu}g/mL$, respectively. The limits of detection and quantification, respectively, were 0.00488 and $0.03906{\mu}g/mL$ for quercetin, 0.62500 and $2.50000{\mu}g/mL$ for bisdemethoxycurcumin, 0.07813 and $0.31250{\mu}g/mL$ for demethoxycurcumin, and 0.03906 and $0.07813{\mu}g/mL$ for curcumin. The percent relative intra day standard deviation (% RSD) values were $0.432-0.806{\mu}g/mL$, $0.576-0.723{\mu}g/mL$, $0.635-0.752{\mu}g/mL$ and $0.655-0.732{\mu}g/mL$ for quercetin, bisdemethoxycurcumin, demethoxycurcumin and curcumin, respectively, and those for intra day precision were $0.323-0.968{\mu}g/mL$, $0.805-0.854{\mu}g/mL$, $0.078-0.844{\mu}g/mL$ and $0.275-0.829{\mu}g/mL$, respectively. The intra day accuracies were 99.589%-100.821%, 98.588%-101.084%, 9.289%-100.88%, and 98.292%-101.022% for quercetin, bisdemethoxycurcumin, demethoxycurcumin and curcumin, respectively, and the inter day accuracy were 99.665%-103.06%, 97.669%-103.513%, 99.569%-103.617%, and 97.929%-103.606%, respectively. Conclusion: The method was found to be simple, accurate and precise and is recommended for routine quality control analysis of commercial Chinese medicine products containing the flour flavonoids as their principle components in the extracts.

Physico-Chemical Characteristics of Water and Distribution of Vascular Hydrophytes in the West Nakdong River, South Korea (서낙동강 수질의 이화학적 특성과 수생관속식물의 분포)

  • 윤해순;김구연;김승환;이원화;이기철
    • The Korean Journal of Ecology
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    • v.25 no.5
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    • pp.305-313
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    • 2002
  • The physico-chemical characteristics of water and sediment, and structures of vegetation of the vascular hydrophytes were investigated in the West Nakdong River. Water quality was eutrophic according to the mean values and the ranges of water properties such as pH, DO, BOD, chlorophyll a, total nitrogen and phosphate, and other nutrients. A few cases were hypereutrophic for chlorophyll a level in summer. Soil reaction was weak acid. Composition of sediment was mainly sand except in SI(Sinan chideung) of which was mainly clay, and SU(Suan chideung) of which was mainly silt. Flora of vascular hydrophyte had 26 species and 1 variety comprising 16 families. Trapa japonica was dominant species in the sites of DU(Dunchido), GA(Garak chideung) and SU. Nymphoides peltata and Hydrocharis dubia dominated in DA and SI, respectively. Species diversity and evenness were relatively high in SI and SU but dominance was high in DA. After June, water lettuce(Pistia stratiotes) and water hyacinth(Eichhornia crassipes) were flowed from tributary to the river. Standing crop of macrohydrophytes was high in DA from April to August, but it showed maximum standing crop (445g·dw/㎡) in DU after disturbance by explosive growth of exotic plants in October. In comparison with those in 1985, total productivities in DU and GA decreased to 33.5%, and the reduction ratio of dominant species, Trapa japonica was 56.7%. Najas marina, N. minor, Myriophyllum spicatum and Nymphoides indica have disappeared ever since the Nakdong barrage was constructed in the Nakdong river. They were divided into three groups (GA-SU-DU, DA, SI) by cluster analysis. Introduction of the exotic species in this river caused decreasing of endemic plants including endangered species Euryale ferox and rare species Hydocharis dubia, and food plants for waterfowl such as Trapa japonica, Vallisneria asiatica and Potamogeton crispus.

Optimization of Microwave-assisted Extraction Conditions for Total Catechin and Electron Donating Ability of Grape Seed Extracts (포도씨 추출물의 총 카테킨 함량과 전자공여능에 대한 마이크로웨이브 추출조건 최적화)

  • Lee, Eun-Jin;Kim, Jeong-Sook;Kwon, Joong-Ho
    • Food Science and Preservation
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    • v.15 no.6
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    • pp.840-846
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    • 2008
  • Microwave-assisted extraction (MAE) of grape seeds was performed under the different conditions based on a central composite design for independent variables of microwave power ($0{\sim}120\;W$), ethanol concentration ($0{\sim}100%$) and extraction time ($1{\sim}5\;min$). Response surface methodology (RSM) was used to predict the optimum extraction conditions for three dependent variables in grape seed extracts: total yield, total catechin and electron donating ability. Determination coefficients ($R^2$) of regression equations for the three dependent variables were higher than 0.9 (p < 0.01). The optimal MAE conditions to yield the maximum value of total catechin (434.16 mg%) were 122.76 W microwave power, 42.88% ethanol and 4.67 min extraction time. The superimposed contour maps for maximizing the three dependent variables indicated that the MAE condition ranges were 75150 W, 4060% ethanol and 3.55.0 min. The predicted values at the optimized conditions (6.72% total yield, 408.65 mg% total catechin, and 83.33% electron donation ability) were similar to the experimental values. The optimized MAE (112.5 W, 50% EtOH, 4.2 min) was more efficient than the conventional solvent extraction using 80% EtOH, $60^{\circ}C$ for 3h and 150 rpm.

Relationship Between Scrotal Circumference and Semen Production and Reproductive Performance in Hanwoo Bulls (한우 종모우의 고환둘레와 정액생산 및 번식과의 관계)

  • Park, N.H.;Lee, S.S.;Jeong, J.;Won, Y.S.;Kim, N.S.
    • Journal of Animal Science and Technology
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    • v.45 no.4
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    • pp.517-522
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    • 2003
  • Scrotal measurements and semen production records of 19,742 during 7 years from 63 Hanwoo breeding bulls(6${\sim}$7 years of age) were used to determined the relationship between scrotal circumference(SC) and semen production including concentration and total number of sperm. The average of SC is 41.2$\pm$4.54cm; extreme ranges between a low of 34cm to a high of 48cm. Quantity of semen, concentration and total number of sperm are 5.47$\pm$0.89ml/ejaculation, 16.16${\pm}2.78{\times}10^8$/ml and 88.47${\pm}15.24{\times}10^8$/ejaculation, respectively. SC is positively correlated with semen production(0.14 with quantity of semen and 0.15 with total number of sperm). Reproduction data from 16 breeding bulls produced 1,289 offspring from spring 1993 to spring 2000 to examined relationship between SC and reproduction. Rate of fertility and delivery are 0.80$\pm$0.13 and 0.78$\pm$0.15, respectively. Also, SC is positively correlated with delivery rate(r=0.26) and favorably related to fertility rate(r=0.39). These results, that is, - SC correlates positively with semen production and with reproduction -, suggested that SC should be considered when selecting breeding bull.

Quality Characteristics of Southeast Asian Salt-Fermented fish Sauces (동남아산 액젓의 품질특성)

  • CHO Young Je;IM Yeong Sun;PARK Hee Yeol;CHOI Young Joon
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.33 no.2
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    • pp.98-102
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    • 2000
  • To investigate quality characteristics of southeast asian salt-fermented fish sauces, various chemical properties were examined against 13 kinds of southeast asian salt-fermented fish sauces. The range of chemical compositions were $60.6{\~}72.8{\%}$ moisture, $18.2{\~}25.8{\%}ash,\;0.9{\~}13.7{\%}$ crude protein and $14.1{\~}338.6\;mg/100 ml$ VBN. The pH and salinity were $4.66{\~}5.91,\;24.1{\~}30.6{\%}$, respectively. Total nitrogen, amino nitrogen, total free amino acid, and total ATP related compounds (sum of $ATP{\~}IMP$, HxR, Hx and uric acid) were in the ranges of $0.140{\~}2.199g,\;115.4{\~}1,643.0 mg,\;46.4{\~}9,056.3\;mg\;in\;100 ml,\;and\;0.829{\~}9.564 {\mu}mol\;in\;1\;ml$, respectively. Southeast asian salt-fermented lish sauces were rich in tree amino acids, such as glutamic acid, Iysine, leucine, alanine, aspartic acid, valine and isoleucine in the order.

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Improving the Chitinolytic Activity of Bacillus pumilus SG2 by Random Mutagenesis

  • Vahed, Majid;Motalebi, Ebrahim;Rigi, Garshasb;Noghabi, Kambiz Akbari;Soudi, Mohammad Reza;Sadeghi, Mehdi;Ahmadian, Gholamreza
    • Journal of Microbiology and Biotechnology
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    • v.23 no.11
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    • pp.1519-1528
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    • 2013
  • Bacillus pumilus SG2, a halotolerant strain, expresses two major chitinases designated ChiS and ChiL that were induced by chitin and secreted into the supernatant. The present work aimed to obtain a mutant with higher chitinolytic activity through mutagenesis of Bacillus pumilus SG2 using a combination of UV irradiation and nitrous acid treatment. Following mutagenesis and screening on chitin agar and subsequent formation of halos, the mutated strains were examined for degradation of chitin under different conditions. A mutant designated AV2-9 was selected owing to its higher chitinase activity. To search for possible mutations in the whole operon including ChiS and ChiL, the entire chitinase operon, including the intergenic region, promoter, and two areas corresponding to the ChiS and ChiL ORF, was suquenced. Nucleotide sequence analysis of the complete chitinase operon from the SG2 and AV2-9 strains showed the presence of a mutation in the catalytic domain (GH18) of chitinase (ChiL). The results demonstrated that a single base change had occurred in the ChiL sequence in AV2-9. The wild-type chitinase, ChiL, and the mutant (designated ChiLm) were cloned, expressed, and purified in E. coli. Both enzymes showed similar profiles of activity at different ranges of pH, NaCl concentration, and temperature, but the mutant enzyme showed approximately 30% higher catalytic activity under all the conditions tested. The results obtained in this study showed that the thermal stability of chitinase increased in the mutant strain. Bioinformatics analysis was performed to predict changes in the stability of proteins caused by mutation.

Effects of Hyperbaric Pressure on Cellular Morphology, Proliferation and Protein Expression of Jurkat Cell

  • Oh, Eun-Ha;Oh, Sang-Nam;Im, Ho-Sub;Lee, Joo-Hyun;Kim, Jin-Young;Moon, Joo-Hee;Hong, Eun-Young;Kim, Yang-Hee;Yang, Min-Ho;Lim, Yong-Chul;Park, Sun-Young;Lee, Eun-Il;Sul, Dong-Geun
    • Molecular & Cellular Toxicology
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    • v.1 no.2
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    • pp.116-123
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    • 2005
  • The application of high pressure on cellular morphology, proliferation and protein expression of Jurkat cells (human T lymphocyte cell line) has been extensively investigated. In the present study, we manufactured a novel pressure chamber that modulates 5% $CO_{2}$, temperature and pressure (up to 3 ATA). Jurkat cells was incubated 2 ATA pressure and analyzed cellular morphology and growth using an electron microscopy and MTT assay. The cells showed the morphological changes in the cell surface, which appeared to cause a severe damage in cell membrane. The growth rate of the cells under 2 ATA pressure decreased as cultured time got increased. Furthermore, a long term exposure of high pressure on Jurkat cells may act as one of the important cellular stresses that leads to inducing cell death. Cellular proteomes were separated by 2-dimensional electrophoresis with pH 3-10 ranges of IPG Dry strips. And many proteins showed significant up-and-down expressions with hyperbaric pressure. Out of all, 10 spots were identified significantly using matrix-assisted laser desorption/ionization-time of fight (MALDI-TOF) mass spectrometry. We and found that 9 protein expressions were decreased and one protein, heat shock protein HSP 60, was increased in Jurkat cells under 2 ATA. Identified proteins were related to lipid metabolism and signal transduction.

Simultaneous Determination of Hesperidin and Glycyrrhizin in Pyungwi-san by HPLC/DAD (HPLC-DAD를 이용한 평위산 중의 Hesperidin 및 Glycyrrhizin의 동시분석법 확립)

  • Lee, Mi-Kyeong;Choe, Ok-Gyeong;Park, Jin-Ho;Cho, Jung-Hee;Kim, Do-Hoon;Baek, Ju-Hyun;Kim, Hyo-Jin;Lee, Ki-Yong;Kim, Sang-Du;Kim, Young-Choong;Sung, Sang-Hyun
    • Korean Journal of Pharmacognosy
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    • v.39 no.3
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    • pp.199-202
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    • 2008
  • A high performance liquid chromatographic (HPLC) method for the simultaneous determination of hesperidin and glycyrrhizin was established for the quality control of traditional herbal medicinal preparation, Pyungwi-san (PWS). Separation and quantification were successfully achieved with a Waters XTerra RP18 column ($5{\mu}m$, 4.6 mm I.D. ${\times}$ 150 mm) by gradient elution of a mixture of acetonitrile and water containing 0.03% phosphoric acid (pH 2.03) at a flow rate of 1.0 ml/min. The diode-array UV/vis detector (DAD) was used for the detection and the wavelength for quantification was set at 230 nm. The presence of hesperidin and glycyrrhizin in this extract was ascertained by retention time, spiking with each authentic standard and UV spectrum. All four compounds showed good linearity $(r^2>0.995)$ in a relatively wide concentration ranges. The R.S.D. for intra-day and inter-day precision was less than 7.0% and the limits of detection (LOD) were less than 60 ng. The mean recovery of each compound was 99.0-105.6% with R.S.D. values less than 4.0%. This method was successfully applied to the determination of contents of hesperidin and glycyrrhizin in three commercial products of PWS. These results suggest that the developed HPLC method is simple, effective and could be readily utilized as a quality control method for commercial PWS products.

Effect of Heat-Treat Methods on the Soluble Calcium Levels in the Commercial Milk Products

  • Yoo, Sung-Ho;Kang, Seung-Bum;Park, Jin-Ho;Lee, Kyung-Sang;Kim, Jin-Man;Yoon, Sung-Sik
    • Food Science of Animal Resources
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    • v.33 no.3
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    • pp.369-376
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    • 2013
  • Milk is well known to be rich in some nutrients such as protein, calcium, phosphorus, and vitamins. In particular, absorption and bioavailability of calcium receive lots of attention because calcium is very little absorbed until it is changed to the ionized form in the intestine. In this study, concentration of the soluble calcium was determined in the commercial bovine milk products, which were processed by different heat-treatment methods for pasteurization. As for general constituents, lactose, fat, protein, and mineral were almost same in the liquid milk products by different processors. Ultrafiltration of the skimmed milk caused little change in the permeate as for lactose content but both fat and protein decreased. pH values ranges from 6.57-6.62 at room temperature and slightly increase after centrifugation, 10,000 g, 10 min. Rennet-coagulation activity was the lowest in the ultra high temperature (UHT-)milk compared to the low temperature long time (LTLT-) and high temperature short time (HTST-)milk products. Each bovine milk products contains 1056.5-1111.3 mg/kg of Ca. The content of sulfhydryl group was the lowest in raw milk compared to the commercial products tested. For the skimmed milks after ultrafiltration with a membrane (Mw cut-off, 3 Kd), soluble Ca in the raw milk was highest at 450.2 mg/kg, followed by LTLT-milk 336.4-345.1 mg/kg, HTST-milk 305.5-313.3 mg/kg, UHT-milk 370.3-380.2 mg/kg in the decreasing order. After secondary ultrafiltration with a membrane (Mw cut-off, 1 kD), total calcium in raw milk had a highest of 444.2 mg/kg, and those in the market milk products. As follow: UHT-milk, 371.3 to 378.2 mg/kg; LTLT-milk, 333.3 to 342.2 mg/kg; HTST-milk 301.9 to 311.2 mg/kg in a decreasing order.