• Title/Summary/Keyword: pH-sensitive

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Antioxidative and Nitrite Scavenging Activity of Pine Needle and Green Tea Extracts (솔잎 및 녹차추출물의 항산화성 및 아질산염 소거작용)

  • 김수민;조영석;성삼경;이일구;이신호;김대곤
    • Food Science of Animal Resources
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    • v.22 no.1
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    • pp.13-19
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    • 2002
  • The natural sources extracted from green tea and pine needle were utilized to investigate the effects of extracts on free radical reaction, lipid oxidation and nitrite scavenging ability. The degree of lipid oxidation is very sensitive to kinds of oil emulsion reacted with iron sources and oxygen species. The antioxidants of extracts from green tea and pine needle were different depending on concentration of extracts, which were a lower TBARS value in 0.3% extracts concentration, compared to 0.1% extracts concentration. And also, the binding ability on iron sources was superior in hot water extracts, but oxygen scavenging ability was the lowest TBARS values in ethanol extracts. The hydroxyl radical scavenging ability of green tea and pine needle extracts had a little low TBARS value in 0.1% and 0.3% extracts concentration in deoxyribose. The ethanol extracts of pine needle were higher than those of hot water extracts on the basis of Fe$\_$2+/ ion content. The ascorbic acid content of green tea showed 14.3 mg/100g in hot water extracts and 16.7 mg/100 g in ethanol extracts. Electron donating ability of extracts showed difference depending on extracts concentration, which were higher in ethanol extracts than those of hot water extracts. The nitrite scavenging effects were tended to be different depending on pH value, however they were decreased overall as pH value was increased. Especially, the nitrite scavenging ability of 0.3% extracts from green tea and pine needle were the mosts effective in pH 1.2 and pH 3.0, which were showed 95% nitrite scavenging ability.

The Usefulness of Selected Physicochemical Indices, Cell Membrane Integrity and Sperm Chromatin Structure in Assessments of Boar Semen Sensitivity

  • Wysokinska, A.;Kondracki, S.;Iwanina, M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.12
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    • pp.1713-1720
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    • 2015
  • The present work describes experiments undertaken to evaluate the usefulness of selected physicochemical indices of semen, cell membrane integrity and sperm chromatin structure for the assessment of boar semen sensitivity to processes connected with pre-insemination procedures. The experiments were carried out on 30 boars: including 15 regarded as providers of sensitive semen and 15 regarded as providers of semen that is little sensitive to laboratory processing. The selection of boars for both groups was based on sperm morphology analyses, assuming secondary morphological change incidence in spermatozoa as the criterion. Two ejaculates were manually collected from each boar at an interval of 3 to 4 months. The following analyses were carried out for each ejaculate: sperm motility assessment, sperm pH measurement, sperm morphology assessment, sperm chromatin structure evaluation and cell membrane integrity assessment. The analyses were performed three times. Semen storage did not cause an increase in the incidence of secondary morphological changes in the group of boars considered to provide sperm of low sensitivity. On the other hand, with continued storage there was a marked increase in the incidence of spermatozoa with secondary morphological changes in the group of boars regarded as producing more sensitive semen. Ejaculates of group I boars evaluated directly after collection had an approximately 6% smaller share of spermatozoa with undamaged cell membranes than the ejaculates of boars in group II ($p{\leq}0.05$). In the process of time the percentage of spermatozoa with undamaged cell membranes decreased. The sperm of group I boars was characterised with a lower sperm motility than the semen of group II boars. After 1 hour of storing diluted semen, the sperm motility of boars producing highly sensitive semen was already 4% lower ($p{\leq}0.05$), and after 24 hours of storage it was 6.33% lower than that of the boars that produced semen with a low sensitivity. Factors that confirm the accuracy of insemination male selection can include a low rate of sperm motility decrease during the storage of diluted semen, low and contained incidence of secondary morphological changes in spermatozoa during semen storage and a high frequency of spermatozoa with undamaged cell membranes.

Changes on Photosynthesis and SOD Activity in Platanus orientalis and Liriodendron tulipifera According to Ozone Exposing Period (오존 노출 시간에 따른 버즘나무와 백합나무의 광합성과 SOD 활성 변화)

  • Lee Jae-Cheon;Oh Chang-Young;Han Sim-Hee;Kim Pan-Gi
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.7 no.2
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    • pp.156-163
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    • 2005
  • This study was conducted to compare the physiological and biochemical responses of P. orientalis and L. tulipifera in response to ozone. One-year-old seedlings of P. orientalis and L. tulipifera were exposed to 100 ppb ozone concentration for 2, 4, or 8 hr/day for 1 week. Photosynthesis, stomatal conductance and ozone uptake rate were measured daily, and chlorophyll fluorescence, carboxylation efficiency, chlorophyll content, and SOD activity were measured after 1 week. In P. orientalis, photosynthesis and stomatal conductance were not decreased in the 2h/day ozone treatment, but the L. tulipifera response was more sensitive even in the 2h/day ozone treatment. Increased treatment time decreased photosynthesis and stomatal conductance. Chlorophyll fluorescence was not significantly different among treatment times. However, carboxylation efficiency decreased with increased treatment time, and L. tulipifera was more sensitive than P. orientalis. Chlorophyll content did not differ with species or treatment time. SOD activity response was greater in L. tulipifera than in P. orientalis, increasing to $131\%$ of pretreatment observations. Therefore it was concluded that L. tulipifera was more responsive and had lower ozone tolerance than P. orientalis.

Pysiological Responses of Diploid and Triploid Far Eastern Catfish, Silurus asotus to Water Temperature Stress

  • Lee, Hyo Bin;Kim, Dong Soo;Gil, Hyun Woo;Park, In-Seok
    • Development and Reproduction
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    • v.22 no.2
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    • pp.165-174
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    • 2018
  • The aim of study is to contribute to this knowledge-base by investigating the respiratory function, the metabolic rate and the difference of physiological responses un-der low water temperature ($20^{\circ}C{\rightarrow}15^{\circ}C$) stress be-tween diploid and triploid far eastern catfish, Silurus asotus. During the 48 hrs of water temperature stress exposure time, the respiratory frequencies, $CO_2$ and ${NH_4}^+$ concentrations of diploid had higher values than those of triploid (p<0.05). However, pH of triploid was higher than those of diploid (p<0.05), and oxygen consumption rate was not different between diploid and triploid (p>0.05). The level of plasma cortisol and plasma glucose of triploid was lower than those of the diploid (p<0.05). However, in case of lactic acid, there were not significant between triploid and diploid (p>0.05). These results suggest that diploid was more sensitive for low water temperature stress response than triploid in this species.

Highly Sensitive and Selective Ethanol Sensors Using Magnesium doped Indium Oxide Hollow Spheres

  • Jo, Young-Moo;Lee, Chul-Soon;Wang, Rui;Park, Joon-Shik;Lee, Jong-Heun
    • Journal of the Korean Ceramic Society
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    • v.54 no.4
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    • pp.303-307
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    • 2017
  • Pure $In_2O_3$, 0.5 and 1.0 wt% Mg doped $In_2O_3$ hollow spheres were synthesized by ultrasonic spray pyrolysis of a solution containing In-, Mg-nitrate and sucrose and their gas sensing characteristics to 5 ppm $C_2H_5OH$, p-xylene, toluene, and HCHO were measured at 250, 300 and $350^{\circ}C$. Although the addition of Mg decreases the specific surface area and the volume of meso-pores, the gas response (resistance ratio) of the 0.5 wt% Mg doped $In_2O_3$ hollow spheres to 5 ppm $C_2H_5OH$ at $350^{\circ}C$ (69.4) was significantly higher than that of the pure $In_2O_3$ hollow spheres (24.4). In addition, the Mg doped $In_2O_3$ hollow spheres showed the highest selectivity to $C_2H_5OH$. This was attributed to the dehydrogenation of $C_2H_5OH$ assisted by basic MgO into reactive $CH_3CHO$ and $H_2$.

Sensitive Determination of Pinaverium Bromide in Human Plasma by LC-ESI-MS/MS : Applicability to Oral Bioavailability Determination (LC-ESI-MS/MS를 이용한 생체시료 중 브롬화피나베리움의 고감도 분석 및 이를 이용한 생체이용률 평가)

  • Park, Seok;Lee, Ye-Rie;Kim, Ho-Hyun;Lee, Hee-Joo;Kim, Yoon-Gyoon;Youm, Jeong-Rok;Han, Sang-Beom
    • Journal of Pharmaceutical Investigation
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    • v.34 no.6
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    • pp.513-519
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    • 2004
  • A sensitive method for quantification of pinaverium bromide in human plasma was established using liquid chromatography-electrospray ionization tandem mass spectrometry(LC-ESI-MS/MS). Glimepiride was used as internal standard. Pinaverium bromide and internal standard in plasma sample were extracted using tert-butylmethylether(TBME). A centrifuged upper layer was then evaporated and reconstituted with mobile phase of acetonitrile-5 mM ammonium formate (80/20, pH 3.0). The reconstituted samples were injected into a $C_{18}$ reversed-phase column. Using MS/MS with multiple reaction monitoring (MRM) mode, pinaverium and glimepirde were detected without severe interference from human plasma matrix. Pinaverium produced a protonated precursor ion $([M+H]^+)$ at m/z 510.3 and a corresponding product ion at m/z 228.9. Internal standard produced a protonated precursor ion $([M+H]^+)$ at m/z 491.5 and a corresponding product ion at m/z 352.0. Detection of pinaverium bromide in human plasma was accurate and precise, with limit of quantitation at 0.5 ng/ml. The method has been successfully applied to bioavailability study of pinaverium bromide tablet in Korean healthy male volunteers. Pharmacokinetic parameters such as $AUC_t,\;C_{max},\;T_{max},\;K_{el}\;and\;t_{1/2}$ were calculated.

Determination of Intestinal Disappearance of Lysine and Methionine Derived from Ruminally Protected Lysine and Methionine in Holstein Heifers

  • Watanabe, K.;Sato, H.;Kobayashi, T.;Katoh, K.;Obara, Y.
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.4
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    • pp.549-554
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    • 2003
  • In order to estimate the availability of ruminally-protected Lys (RPLys) and Met (RPMet), quantitative changes of free Lys and Met in the total abomasal outflow and feces were determined in three Holstein heifers with a T-shaped duodenal cannula. RPLys was prepared by coating Lys with fat and RPMet with a pH-sensitive polymer. RPLys and RPMet containing 30 g of each amino acid were supplied together to heifers, and total abomasal outflow was collected hourly from the T-shaped duodenal cannula for a 48 h period. Collected abomasal outflows were fractionated into liquid and solid phases to measure free Lys and Met concentration. At 2 wk after total abomasal outflow sampling, heifers were supplied RPLys and RPMet together again, and total feces were collected every 12 h for a 3 d period t estimate excreted RPLys and RPMet in feces. The amounts of Lys and Met recovered from the liquid fractions of abomasal outflow were estimated to be $23.9{\pm}8.3%$ and $68.6{\pm}3.6%$ (p=0.008) of RPLys and RPMet ingested, respectively. Final intestinal disappearances of Lys and Met were estimated to be $49.5{\pm}2.6%$ and $78.2%{\pm}6.5%$ (p=0.015) of ingested RPLys and RPMet, respectively.

Optimization of coagulation conditions for pretreatment of microfiltration process using response surface methodology

  • Jung, Jungwoo;Kim, Yoon-Jin;Park, Youn-Jong;Lee, Sangho;Kim, Dong-ha
    • Environmental Engineering Research
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    • v.20 no.3
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    • pp.223-229
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    • 2015
  • The application of coagulation for feed water pretreatment prior to microfiltration (MF) process has been widely adopted to alleviate fouling due to particles and organic matters in feed water. However, the efficiency of coagulation pretreatment for MF is sensitive to its operation conditions such as pH and coagulant dose. Moreover, the optimum coagulation condition for MF process is different from that for rapid sand filtration in conventional drinking water treatment. In this study, the use of response surface methodology (RSM) was attempted to determine coagulation conditions optimized for pretreatment of MF. The center-united experimental design was used to quantify the effects of coagulant dose and pH on the control of fouling control as well as the removal organic matters. A MF membrane (SDI Samsung, Korea) made of polyvinylidene fluoride (PVDF) was used for the filtration experiments. Poly aluminum chloride (PAC) was used as the coagulant and a series of jar tests were conducted under various conditions. The flux was $90L/m^2-h$ and the fouling rate were calculated in each condition. As a result of this study, an empirical model was derived to explore the optimized conditions for coagulant dose and pH for minimization of the fouling rate. This model also allowed the prediction of the efficiency of the coagulation efficiency. The experimental results were in good agreement with the predictions, suggesting that RSM has potential as a practical method for modeling the coagulation pretreatment for MF.

Ca-dependent Alteration in Basal Tone, Basal $^{45}Ca$ Uptake and $^3H-nitrendipine$ Binding in the Aorta of Spontaneously Hypertensive Rats

  • Chang, Seok-Jong;Jeon, Byeong-Hwa;Kim, Hoe-Suk
    • The Korean Journal of Physiology
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    • v.28 no.1
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    • pp.27-35
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    • 1994
  • We investigated the alterations in basal tone of aortic strips by changing the Ca concentration, basal $^{45}Ca$ uptake and $^3H-nitrendipine$ binding of the single cells of aortic smooth muscles in the spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats. While the basal tone of the aortic strips in WKY rats was not affected by alteration of Ca concentration, that in SHR was decreased by the removal of Ca from the bath solution and was recovered by the restoration of Ca to normal levels. This contraction increased in a Ca concentration-dependent manner and reached a maximum at 2 mM Ca. The basal tone of aorta in SHR was suppressed by verapamil $(10^{-6}M)$. The basal tone of aorta in SHR increased about 50% in the strips of endothelial rubbing, compared with that of intact endothelium. Basal $^{45}Ca$ uptake in the aortic single smooth muscle cells of SHR was greater than that of WKY (p<0.01), Specific bindings of $[^3H]nitrendipine$ in the aortic single smooth muscles of SHR and WKY were saturable. The dissociation constant $(K_d)\;was\;0.71{\pm}0.15\;and\;1.18{\pm}0.08nM$ SHR, respectively, and the difference in $K_d$ between two strains was statistically significant (p<0.03). The maximal binding capacity $(B_{max})\;was\;34.6{\pm}3.2\;and\;47.4{\pm}4.3\;fmol/10^6$ SHR respectively, and the difference of $(B_{max})$ between two strains was statistically significant (p<0.05). from the above results, it is suggested that the increase of Ca influx via potential-operated Ca channels and the increase of the number of dihydropyridine-sensitive Ca channels contribute to high basal tone of the aortic strips in SHR.

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Acid Resistance of Non-O157 Shiga Toxin-Producing Escherichia coli Adapted in Fruit Juices in Simulated Gastric Fluid (위합성용액에서 과일주스에 노출한 Non-O157 Shiga Toxin-Producing Escherichia coli의 산 저항성 평가)

  • Kim, Gwang-Hee;Oh, Deog-Hwan
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.4
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    • pp.577-584
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    • 2016
  • The objectives of this study were I) to compare the acid resistance (AR) of seven non-O157 Shiga toxin-producing Escherichia coli (STEC) serogroups, including O26, O45, O103, O111, O121, O145, and O157:H7 STEC isolated from various sources, in 400 mM acetic acid solution (AAS) at pH 3.2 and $30^{\circ}C$ for 25 min with or without glutamic acid and II) to determine strain survival upon exposure to simulated gastric fluid (SGF, pH 1.5) at $37^{\circ}C$ for 2 h after acid adaptation in apple, pineapple, orange, and strawberry juices at pH 3.8, $4^{\circ}C$ and $20^{\circ}C$. Results show that the O111 serogroup strains had the strongest AR (0.12 log reduction CFU/mL) which was very similar to that of O157:H7 STEC (P>0.05), compared to other serogroups in AAS without glutamic acid, whereas O26 serogroup strains showed the most sensitive AR. However, there was no significant (P>0.05) difference of AR among seven serogroups in AAS with glutamic acid. In the SGF study, 05-6545 (O45:H2), 08023 (O121:H19), and 03-4669 (O145:NM) strains adapted in fruit juices at $4^{\circ}C$ and $20^{\circ}C$ displayed enhanced survival with exposure to SGF for 60 min compared to 06E0218 (O157:H7) strains (P<0.05). In addition, 4 STEC strains adapted in pineapple juice at $4^{\circ}C$ showed enhanced survival with exposure to SGF for 60 min compared to those strains acid-adapted in the other fruit juices. Generally, adaptation at $4^{\circ}C$ in fruit juices resulted in significantly enhanced survival levels compared to acid-adapted at $20^{\circ}C$ and non-adapted conditions. The AR caused by adaptation in fruit juices at low temperature may thus increase survival of non-O157 STEC strain in acidic environments such as the gastrointestinal tract. These results suggest that more careful strategies should be provided to protect against risk of foodborne illness by non-O157 STEC.