• Title/Summary/Keyword: pH Level

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Simple Semiquantitative Determination and Selective Preconcentration of Trace Heavy Metals in Environmental Pollutants : Determination of Chromium (VI) with DPC Gel (環境汚染 重金屬의 選擇的 濃縮 및 簡易分析法 : DPC 겔의 의한 크롬 (VI) 의 定量)

  • Yong Keun Lee;Kyu Ja Whang;In Hwa Woo
    • Journal of the Korean Chemical Society
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    • v.25 no.4
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    • pp.275-282
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    • 1981
  • A simple semiquantitative procedure was developed for the determination of sub-ppm level of chromium(VI) in aquatic samples by using an analytical micro-column packed with diphenylcarbazide(DPC) gel beads. DPC gel beads were prepared by swelling XAD-2 resin(115∼150 mesh in dry condition) in ethanol for 10min, packing into a glass column(1.5 mm bore, 65nm length) and adsorbing 1ml of ethanol solution of $2{\times}10^{-3}M$ DPC for 20min at room temperature. When 0.5ml of ethanol solution containing chromium(VI) was passed through the DPC gel column for 40min, the original white color of the reagent gel turned to red-violet from the up-stream of the column. As the length of colored band was proportional to the total amount of chromium(VI) in the sample solution passed through the column, the concentration of chromium(VI) could be determined from the calibration line which had been prepared by using the standard solution. Chromium(VI) ion as small as from 0.1 to 0.8 ppm could be determined with ${\pm}5{\sim}{\pm}15{\%}$ relative errors. Since other interfering cations were few, 100-fold excess of Fe(III), 50-fold excess of Cu(II) could be masked with EDTA. This method was successfully applied to the analysis of chromium(VI) in industrial effluents.

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Antifungal Activity of Bacillus sp. BCNU 2003 against the Human Pathogenic Fungi (인체 병원성 진균에 대한 Bacillus sp. BCNU 2003의 항진균 효과)

  • Choi, Hye-Jung;Yang, Uk-Hee;Kim, Ya-Ell;Choi, Yeon-Hee;Ahn, Cheol-Soo;Jeong, Young-Kee;Kim, Dong-Wan;Joo, Woo-Hong
    • Journal of Life Science
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    • v.20 no.2
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    • pp.269-274
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    • 2010
  • An antifungal antibiotic-producing strain, BCNU 2003, was isolated from forest soil in Korea. The morphological and physiological characters, and 16S rRNA sequences analysis of strain BCNU 2003 identified this strain as Bacillus genus. The Bacillus sp. BCNU 2003 showed strong antifungal activities against Aspergillus niger, Trichophyton mentagrophytes and Trichophyton rubrum with inhibition ranging from 62.05 to 63.49% by using dual culture technique. Bacillus sp. BCNU 2003 produced a maximum level of antifungal substances under aerobic incubation at 28oC and pH 6.5-7.2 for 6 days in LB broth. Ethyl acetate extract of the cultured broth showed strong antifungal activity and a broad antifungal spectrum against various pathogenic fungi. The minimum inhibitory concentration (MIC) values for its active extracts ranged between 0.0625 mg/ml and 1 mg/ml. In addition, Bacillus sp. BCNU 2003 was determined to have the ability to produce enzymes such as amylase, protease, gelatinase and catalase.

Estimation of Habitat Suitability Index of Fish Species in the Geum River Watershed (금강수계 하천에서의 어류 서식처적합도지수 산정)

  • Kang, Hyeongsik;Im, Dongkyun;Hur, Jun Wook;Kim, Kyu-Ho
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.31 no.2B
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    • pp.193-203
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    • 2011
  • With the recent growth of environmental and ecological interests, various river restoration and habitat environment creation projects are being carried out. For this, the estimation of the habitat flow discharge is important. In U.S. and Europe nations, The instream flow incremental methodology (IFIM) has been used to estimate the habitat discharge. IFIM is the method that can be applied to evaluate the flow discharge for the suitable habitat. To use the IFIM in river, a habitat suitability index(HSI) for the target organism is needed. However, HSIs for only two species of Zacco platypus and Zacco temminckii were proposed from the field monitoring. Thus, for the estimation of the ecological flow rate for a group of fish, the development of the HSIs for various fish are necessary. In this study, physical data such as water level and flow rate, chemical data such as acidity and dissolved oxygen, and life data such as fish types and population are collected in Keum river watershed. Based on the 2,736 field data, HSIs for the following 6 fish are developed: Zacco platypus, Zacco temminckii, Microphysogobio yaluensis, Coreoleuciscus splendidus, Pungtungia herzi, Pseudogobio esocinus. Through the comparison with HSIs in the literature, the developed HSIs are modified. Also, the limits of Froude number, pH, and DO for 6 fish are proposed. The HSIs developed in this study can be utilized as a essential data for performing river project evaluations.

Modern Reproducing of Jehotang Method (제호탕(醍醐湯)의 현대적 재현)

  • JI, Myoung-Soon;Jeon, Won-Kyung;Ko, Byoung-Seob;Anh, Sang-Woo;Yoon, Chang-Yeol
    • The Journal of Korean Medical History
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    • v.21 no.1
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    • pp.59-69
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    • 2008
  • The "tang[tɑ:ŋ]" in Korean pronounciation means the beverage made of boiled medicinal herbs. The"Jeho-tang", the name of Drink in this abstract, is described in a variety of medical books including the "Dongeui Bogam" as being effective for illness from the summer heat in promoting digestion, curing the heatstroke and bringing it to a halt. The Drink was used as the Royal gifts granted to retainers and royal families on the Day of Dano-festival on the fifth of the fifth month of the year according to the lunar calendar, the items of encouragement for those who worked hard in sacrifices, and the awards for students of Confucianism who were proficient in their learning. The Jeho-tang used in this study was scientifically cooked again after a long time in history through looking at the methods written in the documents concerned with the Drink such as the "Dongeui Bogam" and the "Taste of Korea". In preparation of the medicinal herbs for the Drink, the powder of thinner than 30 mesh of the "Prunus mume", which is a species of Asian plum in the family of Rosaceae, and those of 50 mesh of the "Santalum album", which is the fragrant wood of trees in the genus Santalum and the "Amomum Xanthioides", which is produced in Vietnam and is the name of a kind of herb medicines, being very effective in the desease caused from heatstrare, were used. The sugar concentration of the honey boiled down long time at low heat was $82.43^{\circ}Bx$. When cooking in a double boiler, the inner part of the liquid for the Drink was kept at $80^{\circ}C$ for 12 hours to make it finished in a state of ointment. In the general composition of the finished Jeho-tang, the moisture content was 24.4%, 1.3% of crude fat, 1.4% crude protein and 0.7% ash, along with pH3.2. The acceptance on the whole was come out to be the highest in the sample diluted with the drinking water of 7-fold of the Jeho-tang, indicating that the 7-fold's addition of water was optimum level for drinking. In the Drink cooked by a vaccum pressure extractor for herb medicine, which was developed to improve the art of cooking, the longer the time of pressure was, the less the heterogeneous feeling at tongue was and the more the glossiness of the Drink was. The Jeho-tang cooked under pressure for 7 hours received an excellent evaluation in its acceptability in every way.

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Seasonal Variation in Community Structure of Subtidal Seaweeds in Jeju Island, Korea (제주도 주변 해역 조하대 해조류 군집구조의 계절적 변동)

  • Kim, Bo Yeon;Ko, Jun-Cheol;Ko, Hyuck Joon;Park, Sung Eun;Cha, Hyung Kee;Choi, Han Gil
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.5
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    • pp.607-618
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    • 2013
  • Marine macroalgal community structures and characteristics of ocean environmental factors were examined seasonally at four sites in Jeju Island, Korea, from March to November 2012. A total of 71 macroalgal species were identified, including 9 green, 7 brown, and 55 red algae. Peyssonnelia capensis occurred at all study sites and in all seasons. The average annual biomass of seaweed was 991.84 g wet $wt/m^2$, with seasonal variations from 543.80 g in autumn to 1,284.17 $g/m^2$ in summer. A green alga, Codium coactum, was the dominant species, occupying 21.31% (211.39 $g/m^2$) of the total algal biomass in Jeju Island. Subdominant species were Ecklonia cava and Lithophyllum okamurae, comprising 20.85% (206.75 $g/m^2$) and 19.64% (194.75 $g/m^2$), respectively, of the total algal biomass in Jeju Island. The vertical distribution of subtidal seaweeds was represented by L. okamurae at 5 m depth, C. coactum at 10 m depth, E. cava at 5-10 m depth and P. capensis at the 20 m depth level. In the present study, crustose coralline algae, which predominated on barren ground, were subdominant species at all study sites. Community indices varied between 0.51-0.63 for dominance index (DI), 5.53-8.14 for richness index (R), 0.51-0.63 for evenness index (J'), and 2.04-2.32 for diversity index (H'). On the basis of seaweed biomass and community indices, Sinchang was the best preserved coastal area, showing maximal values in biomass, and evenness- and diversity-indices, and minimal value in the dominance index, representing stable environmental conditions. In contrast, the Onpyung and Topyeong sites, located near tourist venues such as Udo and Seogwipo were relatively poor habitats based on community indices and biomass. The present results could imply that climate changes alter seaweed community structure, and long-term monitoring of the study sites is required.

Effect of Singeing Time on Physico-Chemical Characteristics of Duck Meat (오리육의 화염 처리 수준에 따른 이화학적 특성)

  • Chae, H.S.;Yoo, Y.M.;Ahn, C.N.;Jeong, S.G.;Ham, J.S.;Lee, J.M.;Singh, N.K.
    • Korean Journal of Poultry Science
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    • v.33 no.4
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    • pp.273-281
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    • 2006
  • Singeing has always been equated with meat color alteration through lipid oxidation and microbial population. Singeing method has always been employed far removing duck feathers, however, the effect of singeing on storage characteristic of duck meat has not been investigated extensively. The study was therefore, designed to Investigate the effect of singeing on duck meat during storage extensively. For the purpose, study was categorized into three groups namely A, B, and C, representing 0, 50 and 70 seconds of singeing time. Singeing was performed on 100 birds in each group, however, only 20 singed birds from each treatment groups were further selected to analyse them subsequently during storage. Analysis revealed that with 70 seconds singeing time drip loss was significantly (p<0.05) higher at $6mgf/cm^2$ compared to 50 seconds of singeing. With 70 seconds treatment breast meat apparently appeared black, where as with 50 seconds treatment no change was observed. Breast showed low redness with more duration of treatment compared to less treatment duration. Yellowness increased, springiness declined and no change was observed in cohesiveness and chewiness with high treatment time. There was increase in the TBARS and VBN, freshness did not change for first 5 days, however, K values started to increase later on indicated decline in freshness. Conclusively, it was inferred from the study that 50 seconds singeing does not make much alternation in the quantitative traits and at the same time maintains the microbial level under permissible limit.

Genetic Trends for Laying Traits in the Brown Tsaiya (Anas platyrhynchos) Selected with Restricted Genetic Selection Index

  • Chen, D.T.;Lee, S.R.;Hu, Y.H.;Huang, C.C.;Cheng, Y.S.;Tai, C.;Poivey, J.P.;Rouvier, R.
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.12
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    • pp.1705-1710
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    • 2003
  • A small body size of Brown Tsaiya laying duck is desirable to reduce maintenance requirements, so the body weight at 40 weeks of age (BW40) has to be maintained at its current level. Egg weight has to be maintained at around 65 g to meet market requirements. Eggshell strength at 40 weeks of age (ES40) must to be increased in order to maintain a low incidence of broken eggs. Thus, number of eggs laid up to 52 weeks of age (EN52) has to be increased without negative correlated response on ES40. A new linear genetic selection index was used: $I_g=a_0{\times}GEW40\;(g)+a_1{\times}GBW40\;(g)+a_2{\times}GES40\;(kg/cm^2)+a_3{\times}GEN52\;(eggs)$ where GEW40, GBW40, GES40 and GEN52 were the multitrait best linear unbiased prediction (MT-BLUP) animal model predictors of the breeding values respectively of egg weight and body weight at 40 weeks of age (EW40, BW40), ES40 and EN52. The coefficients $a_0$, $a_1$, $a_2$ and $a_3$ were calculated with constraints of 0.0 g, 0.0 g and $0.013kg/cm^2$ for expected genetic gains in EW40, BW40 and ES40 respectively and maximum gain in EN52. Since 1997, the drakes and the ducks were selected according to their own indexes, with this new genetic selection index. From G0 to G4, the average per generation predicted genetic responses in female duck were +0.05 g for EW40, +0.92 g for BW40, $+0.035kg/cm^2$ for ES40 and +2.13 eggs for EN52. Which represented respectively 0.07%, 0.06%, 0.67% and 1.0% of the means of the EW40, BW40, ES40 and EN52. For ES40 and EN52, it represented also respectively 16.1% and 21.6% of the additive genetic standard deviation of these traits. Thevse results indicated that selection of laying Brown Tsaiya by a restricted genetic selection index and with MT-BLUP animal model could be an efficient tool for improving the efficiency of egg production, increasing egg shell strength and egg number while holding egg weight and body weight constants.

The Efficacy of Recombinant Human Follicle Stimulating Hormone (rhFSH) in Human IVF-ET Program (체외수정시술시 유전자 재조합 난포자극호르몬제의 효용성)

  • Han, Kuk-Sun;Lee, Hong-Bok;Song, In-Ok;Park, Yong-Seog;Byun, Hye-Kyung;Jun, Jin-Hyun;Koong, Mi-Kyoung
    • Clinical and Experimental Reproductive Medicine
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    • v.29 no.1
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    • pp.45-56
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    • 2002
  • Objectives: Recently, recombinant FSH (rFSH) has been manufactured using a Chinese hamster ovary cell line transfected with the gene encoding human FSH. Both rFSH and urinary gonadotropin (uFSH) could be used for controlled ovarian hyperstimulation (COH). However, uFSH implies a number of disadvantages, such as batch-to-batch inconsistency, no absolute source control, dependence on large amounts of urine, low specific activity, and low purity. The purpose of this study was to evaluate the efficacy of rFSH in human IVF-ET program. Materials and Methods: A total of 508 infertile women was enrolled in this study. They are classified into rFSH group (n=177) or uFSH group (n=331), and all of them were matched by age and cause of infertility in same period. The $Puregon^{(R)}$ (Organon, Holland) was used as rFSH, and the Metrodin-$HP^{(R)}$ (Serono, Switzeland) and $Humegon^{(R)}$ (Organon, Holland) was used as uFSH. We subdivided the patients into three age groups. The outcomes of IVF-ET program were analyzed using the statistical package for social sciences (SPSS). Results: There was no significant differences in the level of estradiol on hCG injection day, the numbers of retrieved oocytes, matured oocytes, fertilized oocytes, transferred embryos, frozen embryos between the two groups. The total dose (IU) of gonadotropin for COH was significantly lower in the rFSH group compared to uFSH group ($1339{\pm}5491.1$ vs $2527.8{\pm}1075.2$ IU, p<0.001). Clinical pregnancy rate per embryo transfer in the rFSH group showed increasing tendency, compared to the uFSH group, but there was no statistical significance (35.2% vs 29.3%). Our results demonstrated that the relative efficiency of rFSH compared with uFSH is higher in older patients. Conclusions: The ovarian stimulatory effect and clinical outcome of recombinant FSH was similar to that of the urinary gonadotropin. The IVF-ET cycles with significantly lower dose of gonadotropin in rFSH group showed comparable results. Therefore, we suggest that recombinant FSH is more potent and effective than urinary gonadotropin.

Production of Mozzarella Cheese Analogue by Ultrafiltration (한외여과를 이용한 Mozzarella Cheese Analogue 제조에 관한 연구)

  • Lee, Sung-Hui;Song, Kwang-Young;Seo, Kun-Ho;Yoon, Yoh-Chang
    • Journal of Dairy Science and Biotechnology
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    • v.31 no.1
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    • pp.21-33
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    • 2013
  • The purpose of this study was to improve the production of Mozzarella cheese analogues manufactured using mixtures of soy milk and concentrated raw milk by performing ultrafiltration (UF) and to assess the quality of these cheeses during a 30-day storage period at $4^{\circ}C$, relative to that of Mozzarella cheese manufactured with the traditional method. The solid consistency of Mozzarella cheese analogue prepared from milk mixtures was lower than that of cheese manufactured from raw milk or soy milk and increased during storage, which is considered to be the result of decreasing water levels, as well as with increasing soy milk concentrations. In the Mozzarella cheese analogue generated using the milk mixtures, the fat content decreased with increase in the soy milk concentration, while it decreased during the storage period. Lactose levels were lowest in cheese composed of soy milk or raw milk and processed by UF, and decreased during storage in cheese produced using milk mixtures. In milk mixtures containing soy milk, the protein concentration increased with increasing amounts of raw milk and did not change during the storage period. The water-soluble nitrogen compound level was similar between cheeses and increased only slightly during storage. The amount of non-protein nitrogen compounds was higher in the cheese analogue than in the control cheese and tended to increase during storage. Analysis of the physicochemical traits of the Mozzarella cheese analogue yielded the following results: During storage, titratable acidity levels increased while pH tended to decrease. After analysis using electropherograms, it was classified as ${\alpha}$-, ${\beta}$-, or ${\kappa}$-casein. The results of rheometry tests showed that in the Mozzarella cheese analogue prepared from milk mixtures, with raw milk concentrated by UF, increases in concentration rate lead to lowered hardness, elasticity, cohesiveness, and brittleness. When cheese was produced from milk mixtures and concentrated by UF, meltability increased as the concentration rate increased, although to an extent that was less than that observed for the control cheese, and tended to increase during storage. Sensory evaluation showed that the analogue cheese was much better than the control cheese in terms of formation, appearance, and flavor.

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Quality Characteristics and Biogenic Amine Production of Makgeolli Brewed with Commercial Nuruks (시판 누룩으로 제조한 막걸리의 품질특성과 biogenic amine 생성)

  • Jeong, Seok-Tae;Kwak, Hee-Jung;Kim, Soon-Mi
    • Korean Journal of Food Science and Technology
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    • v.45 no.6
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    • pp.727-734
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    • 2013
  • Makgeolli mashes that were brewed using five different commercial nuruks (fermentation starters) were investigated for changes in physicochemistry, microbial diversity, and biogenic amine (BA) production. Mash A brewed with the nuruk (Gaeryang-nuruk) had the highest level of alcohol concentration and the greatest number of yeast cells, whereas mash E had the greatest number of bacterial cells. Only three biogenic amines were detected in the makgeolli mashes: tyramine, putrescine, and cadaverine. Using a PCR-DGGE technique, we observed that mash E had the highest BA production, and had the greatest number of bands on the denaturing gradient gels. We also observed that the numbers of bacterial cells correlated significantly with the putrescine and the total BA content, and that the BA content correlated significantly with the color values (L, a, b). This study shows that the quality of a makgeolli can depend on the type of nuruk. Therefore, we suggest that the quality management of makgeolli should start with the stage of nuruk manufacture.