Effect of pH on PAH Transport in Brush Border Basolateral Membrane Vesicles of Rabbit Proximal Tubule

김용근,우재석,이상호,Kim, Yong-Keun,Woo, Jae-Suk,Lee, Sang-Ho The Korean Physiological Society 1988 대한생리학회지 Vol.22 No.2

The effect of pH on the rate of PAH uptake was studied in rabbit renal basolateral membrane vesicles (BLMV) and brush border membrane vesicles (BBMV). In the absence of Na in incubation medium, a decrease in external $pH(pH_0)$ led to an increase in probenecid-sensitive PAH uptake by BLMV. In the presence of Na, the probenecid-sensitive PAH uptake was unaltered when the $pH_0$ decreased from 8.0 to 6.0 but further decrease in $pH_0$ to 5.5 increased significantly the uptake. The probenecid-sensitive PAH uptake was not affected by an alteration in pH per se in the absence of a pH gradient with or without the presence of Na. However, the presence of Na stimulated the probenecid-sensitive PAH uptake in all pH ranges tested over that measured in the absence of Na. A similar pattern of pH dependence on the PAH uptake was observed in BBMV but the presence of Na did not alter the probenecid-sensitive PAH uptake in the presence and absence of a pH gradient. Kinetic analysis for BLMV showed that Na or pH gradient increased Vmax of the probenecid-sensitive PAH uptake without a change in Km value. These results suggest that PAH is transported by $OH^-/PAH$ exchange process in the luminal membrane, but the pH dependence in the BLMV is not unequivocally consistent with an anion exchange process. The PAH transport is dependent on Na in BLMV but not in BBMV. 가토 신장 근위세뇨관에서 분리한 brush border membrane vesicle(BBMV)과 basolateral membrane vesicle(BBMV)에서 rapid filtration 방법으로 PAH 이동에 대한 pH의 영향을 관찰하였다. BLMV에서 용액내 Na이 없을 때 외부 $pH(pH_0)$를 8.0에서 5.5까지 감소시켰을 때 probenecid-sensitive PAH 이동은 유의하게 증가되었다. 용액내 Na이 있을 때 $pH_0$가 8.0에서 6.0까지 변화하여도 PAH 이동에는 영향이 없었으나 5.5까지 더욱 감소시켰을 때 PAH 이동이 증가하였다. 그러나 vesicle 내 외에 pH gradient없이 $pH_0$를 내부 $pH(pH_1)$와 동일하게 변화시켰을 때 PAH 이동은 영향을 받지 않았다. PH gradient가 없을 때 시험된 pH범위에서 Na은 PAH 이동을 증가시켰다. BBMV에서도 BLMV에서와 유사한 pH 의존성을 보였으나 Na의 존재는 PAH 이동에 영향을 미치지 못하였다. BLMV에서 동력학적 분석 결과 일정한 $pH(pH_1)$에서 $pH(pH_0)$ 감소는 Km에 변화없이 PAH 이동에 대한 Vmax를 유의하게 증가시켰다. 이러한 결과로 BBMV에서 PAH 이동에 대한 pH의 영향은$OH^-/PAH$교환기전에 기인하는 것으로 추측되나 BLMV에서 pH 의존성은 음이온 교환기전만으로 설명될 수 없다. 또한 BLMV에서는 PAH 이동이 Na에 의존하나 BBMV에서는 Na에 의존하지 않음을 가르킨다.

Synergistic effects of oxygen on phosphine for the control of 6 major agricultural pests

Jaeseon Lee,Hyun Kyung Kim,Hyunna Koo,Gil-Hah Kim,Byung Ho Lee 한국응용곤충학회 2016 한국응용곤충학회 학술대회논문집 Vol.2016 No.04

Phosphine(PH3) is very effective fumigant and is widely used to control pests. Oxygen treatment was found to enhance phosphine toxicity and reduce fumigation time. We researched the insecticidal activities and synergistic effects of oxygen with phosphine(PH3) against on adult stage of 6 agricultural pests as Frankliniella occidentalis, F. intonsa, Pseudococcus comstocki, Planococcus citri, Myzus persicae and Tetranychus urticae. Adults F. occidentalis, F. intonsa, P. comstocki and P. citri was highly susceptible to PH3 at 2mg/L for 2h treatment. However, M. persicae and T. urticae were showed very low fumigation effects at 2mg/L for 2h treatment. These 2 pests were treated with PH3 to increase the times (16h and 20h). And we also researched the synergistic effects of PH3 under controlled atmospheres of 50% and 80% oxygen(O2). Increase of the time and atmospheric oxygen showed improving activities of the PH3 in the 2 agricultural pests. Therefore, PH3 is an effective fumigant against F. occidentalis, F. intonsa, P. comstocki and P. citri, and its synergistic effect with oxygen is effective to control M. persicae and T. urticae. PH3 with oxygen could be useful for managing the agricultural and quarantine pests.

혼합주의 종류에 따른 치아의 부식능 차이 평가

김영석 한국산학기술학회 2020 한국산학기술학회논문지 Vol.21 No.1

This study evaluates the erosive potential and effects of mixed alcohols by analyzing the pH, titratable acidity, and fluorescence loss degree (△F). Following alcohol groups were investigated: Soju, Calamansi+soju, Yakult+soju, Cola+soju, and Energy drink+soju. The ratio of soju:beverage in the alcohol mixtures was 7:3. Ed. Notes: The sentence lacks clarity. Please review if the edit correctly portrays the meaning. If not, please revise appropriately. Measurement of the pH and titratable acidity (the amount of 1M NaoH solution required to raise to pH 5.5 (TA5.5) and 7.0 (TA7.0)) of alcohols was achieved by stirring with pH meter. The erosive effect of the alcohol mixtures on bovine tooth (△F) after 1, 2, 4, and 6 hours exposure were analyzed by quantitative light-induced fluorescence (QLF-D). All the mixed alcohols in this study showed an acidic pH, lower than 4.5. The average pH of mixed alcohols was 3.17 ± 0.50 whereas the pH of Soju was 8.6 ± 0.01. The TA5.5 and TA7.0 values of the mixed alcohols were 0.5~18 and 0.5~23.5, respectively. △F of the three tested mixed alcohol groups (except yakult+soju group) were observed to increase in a time-dependent manner. The calamansi mixed alcohol had the highest acidity potential and erosive effect among the tested groups. Taken together, the results indicate that the mixed alcohols have a strong erosive effect and potential on dental enamel. 이번 연구의 목적은 pH, 적정산도, 형광소실도(△F)를 이용하여 혼합주의 부식위험성과 부식능에 대해 평가하고자 하였다. 실험군은 다음과 같이 분류하였다: 소주, 깔라만시+소주, 요구르트+소주, 콜라+소주, 에너지드링크+소주. 혼합주는 소주와 음료수를 7:3의 비율로 혼합하였다. pH와 적정산도(TA5.5, TA7.0; 음료의 pH를 5.5와 7.0까지 끌어올리는데 필요한 1M NaOH의 양)는 교반하면서 pH미터기를 이용하여 측정하였다. 혼합주의 부식능은 우치를 1, 2, 4, 6시간 동안 침적하였다가 각 시간마다 꺼내어 quantitative light-induced fluorescence (QLF-D)를 이용하여 촬영, 분석하였다. 연구 결과, 혼합주는 평균 pH는 3.17 ± 0.50, 소주의 pH는 8.6 ± 0.01를 나타내었다. TA5.5와 TA7.0는 각각 0.5~18, 0.5~23.5의 분포를 나타내었다. 요구르트 혼합주를 제외한 나머지 혼합주의 △F는 시간이 지남에 따라 증가하였으며, 요구르트 혼합주에서는 부식이 나타나지 않았다. 결론적으로, 깔라만시 혼합주가 가장 강한 산성과 부식능을 보였으며, 요구르트가 가장 약한 부식능을 나타냈다. 혼합주는 치아 법랑질에 강한 부식위험성을 가지고 있으므로, 이에 대한 주의와 교육이 필요할 것으로 사료된다.

[Li,La]TiO₃ 코팅용액의 pH에 따른 Li[Ni_0.35Co_0.3Mn_0.35]O₂ 양극의 전기화학적 특성

정광희,김석범,박용준,Jung, Kwang-Hee,Kim, Seuk-Buom,Park, Yong-Joon 한국전기화학회 2011 한국전기화학회지 Vol.14 No.2

[Li,La]$TiO_3$ 코팅용액의 pH를 조절하여 이에 따른 코팅된 $Li[Ni_{0.35}Co_{0.3}Mn_{0.35}]O_2$ 양극활물질의 전기화학적 특성을 관찰하였다. 산화물인 양극분말은 접촉하고 있는 용액의 pH에 따라 표면 전하를 띄게 되는데 양이온인 코팅물질을 균일하게 반응시키기 위해서는 적절한 pH 조절을 통해 양극분말 표면을 음전하 상태로 조절해 주는 것이 필요하다. SEM, TEM 분석을 통해 코팅용액의 pH에 따른 코팅층의 형상변화를 관찰하였으며 다양한 전류밀도로 충전과 방전을 실시하여 코팅용액의 pH에 따른 방전용량, 사이클 특성, 고율특성을 분석하였다. 임피던스잴 cyclic voltammogram 측정을 통해 코팅용액의 pH에 따른 코팅층의 내부저항 변화를 관찰하였으며 이것을 전기화학적 특성과 연관됨을 확인하였다. The surface of $Li[Ni_{0.35}Co_{0.3}Mn_{0.35}]O_2$ cathode was modified by $[Li,La]TiO_3$ coating using pH controlled coating solution. At low pH values (acidic solution), cathode powders, which is oxides, have a positive surface charge, whereas, they have a negative surface charge at high pH values. As a result, their charge could affect the formation of the coating layer on the surface of cathode powder. To determine the optimal pH value, the surface coating of the pristine powder was carried out at various pH values of the coating solution. The surface morphology of coated samples was characterization by SEM and TEM analyses. Impedance analysis and cyclic voltammogram presented that internal resistance of the cell was dependent upon the pH of coating solution.

Effects of Storage Temperature and pH on the Stability of Antibacterial Effectiveness of Garlic Extract against Escherichia coli B34

Kim, Myung-Hee,Kang, Young-Dong,Kyung, Kyu-Hang The Korean Society for Microbiology and Biotechnol 2001 Journal of microbiology and biotechnology Vol.11 No.4

The effect of long-term storage on garlic antibacterial activity was investigated. A concentration of 5% or more garlic was found to be necessary to completely inhibit Eschrichia coli growth in tryptic soy broth. This value is substantially higher than the minimum inhibitory concentration of 1% for E. coli reported previously. pH-modified garlic extract was stored at different temperatures to investigate the impact of storage conditions (i.e., temperature, pH, period of storage) on the stability of the antibacterial activity of the garlic extract used against E. coli B34. The antibacterial effectiveness of the garlic extract against E. coli remained stable when both the storage temperature and the pH of the extract were kept low. When the garlic extract was stored at $40^{\circ}C and above, most or all of the garlic antibacterial activity disappeared after a 24-h storage period, regardless of the storage pH. The antibacterial activity was weakened when the pH of the garlic extract was adjusted to 8, and at low temperatures.

고비표면적 지르코니움 산화물의 제조 및 특성 분석: pH 영향

정예슬,신채호 한국화학공학회 2019 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.57 No.7

침전법으로 환류방법 또는 수열합성법을 이용하여 산·염기점을 갖는 고비표면적 지르코니아를 합성하였다. 제조된지르코니아는 침전제로 수산화암모늄 수용액을 사용하여 Zr 용액의 pH를 2에서 10 범위 내에서 조절하였으며 질소흡착분석, X-선 회절분석(XRD), 이소프로판올 승온탈착법(IPA-TPD), 주사전자현미경 분석, X-선 광전자분광분석, 산-염기점 분석을 통해 IPA 분해반응의 촉매활성과 연관하여 특성분석을 수행하였다. 환류방법을 사용할 시, tetragonal 상이높은 지르코니아를 얻기 위해서는 Zr 용액의 pH가 높아야 하며, pH 9 이상에서는 순수한 tetragonal 상의 지르코니아 합성이 가능하였다. 또한, 비표면적이 큰 지르코니아를 얻기 위해서는 높은 pH가 요구되었으며, pH 10에서 합성한 경우에는 600 oC에서 소성 후에도 260 m2 g-1의 높은 비표면적이 얻어졌다. 하지만 같은 조건 하에서 고압이 수반되는 수열합성에는 40 m2 g-1 이하의 매우 낮은 비표면적을 보였으며, monoclinic 상의 지르코니아가 합성되었다. 고 비표면적tetragonal 상의 지르코니아를 얻기 위해서는 용액의 pH가 가장 큰 영향을 미쳤으며, 용액의 pH와 무관하게 높은 압력이 필요한 수열합성에서는 monoclinic 지르코니아가 생성되었으며 상대적으로 비표면적이 낮게 나타났다. 높은 비표면적과 tetragonal 상을 갖는 지르코니아는 염기점에 비해 산점이 우세하여 IPA 분해반응에서 선택적 탈수반응만 진행되는프로필렌만 생성되었다. High specific surface area zirconia with acid-basic property was synthesized by precipitation using reflux method or hydrothermal synthesis method using ammonium hydroxide solution as precipitant in the range of pH of Zr solution from 2 to 10. The prepared zirconia was characterized by the nitrogen adsorption, X-ray diffraction (XRD), isopropanol temperature programmed desorption (IPA-TPD), scanning electron microscopy and X-ray photoelectron spectroscopy, and the catalytic activity in the IPA decomposition reaction was correlated with the acid-basic properties. When using reflux method, high pH of Zr solution was required to obtain high fraction of tetragonal zirconia, and pure tetragonal zirconia was possible at pH 9 or higher. High pH was required to obtain high specific surface area zirconia, and the hydrous zirconia synthesized at pH 10 had high specific surface area zirconia of 260 m2 g-1 even after calcination at 600 °C. However, hydrothermal synthesis with high pressure under the same conditions resulted in very low specific surface area below 40 m2 g-1 and monoclinic phase zirconia was synthesized. High pH of the solution was required to obtain high specific surface area tetragonal phase zirconia. In hydrothermal synthesis requiring high pressure, monoclinic zirconia was produced irrespective of the pH of the solution, and the specific surface area was relatively low. Zirconia with high specific surface area and tetragonal phase was predominantly acidic compared to basicity and only propylene, which was observed as selective dehydration reaction in IPA decomposition reaction, was produced.

On pH and Ca2+ Oscillations Monitored by pH Electrode and Ca-ISE in Bromate–Sulfite–Ferrocyanide System Introduced Ca-EDTA

Shan Yang,Yu Long Hou,Dao Dao Hu 대한화학회 2015 Bulletin of the Korean Chemical Society Vol.36 No.1

The pH and Ca2+ oscillations of KBrO3–Na2SO3–K4Fe(CN)6 (BSF) system in presence ofEDTAor Ca-EDTA were investigated. Both EDTA and Ca-EDTA can depress the amplitude and period of pH oscillation, and the effects of Ca-EDTA are more obvious. These effects are attributed to the buffer effect in pH change. The Ca2+ oscillation appears as Ca-EDTAintroduced into the BSF system, which is ascribed to the stability of Ca-EDTA being pH-dependent. The pH and pCa (pCa = −log[Ca2+]) oscillations are synchronous in case of higher concentration of Ca-EDTA; however, the chaotic behavior emerged in pCa oscillation arises at lower pH as the concentration of Ca-EDTA is lower. Such observations can be understood by taking into account the interference of H+ on the response of Ca-ISE to Ca2+. Both amplitude and period for pH and pCa oscillations as KCl introduced into the system can be obviously shortened due to the effect of ion strength on the reaction rate of the core oscillator and on the conditional formation constant of Ca-EDTA. The results are significant for determining whether an experimentally observed chaos in chemical systems is of deterministic origin or is due to experimental noise.

The Effect of Salt and pH on the Phase Transition Behaviors of pH and Temperature-Responsive Poly(N,N-diethylacrylamide-co-methylacrylic acid)

Liu, Tonghuan,Fang, Jian,Zhang, Yaping,Zeng, Zhengzhi The Polymer Society of Korea 2008 Macromolecular Research Vol.16 No.8

A series of pH and temperature-responsive (N,N-diethylacrylamide-co-methylacrylic acid) copolymers were synthesized by radical copolymerization and characterized by elemental analysis, Fourier-transform infrared (FT-IR), nuclear magnetic resonance (NMR) $^1H$, $^{13}C$ and LLS. The effects of salt and pH on the phase transition behaviors of the copolymers were investigated by uv. With increasing NaCl concentration, significant salt effects on their phase transition behaviors were observed. UV spectroscopic studies showed that the phase transition became faster with increasing NaCl concentration. In addition, the phase transition behaviors of copolymers were sensitive to pH. The pH and temperature sensitivity of these copolymers would make an interesting drug delivery system.

염기성 pH에서 Enterobacter amnigenus GG0461의 질산이온 흡수증가

최태근,김성태,한민우,김영기 한국응용생명화학회 2008 Journal of Applied Biological Chemistry (J. Appl. Vol.51 No.1

Salt accumulation in soils of greenhouse due to the massive application of nitrogen fertilizers causes salt stress on the various crops, a serious problem in domestic agriculture. Since the majority of the salinity is nitrate, the excess nitrate should be removed; therefore, a bacterial strain having high capacity of nitrate uptake and identified as Enterobacter amnigenus GG0461 was isolated from the soils of greenhouse. Optimum conditions for the bacterial growth and nitrate uptake were investigated. GG0461 was able to grow without nitrate; however, nitrate facilitated the growth. The rate of nitrate uptake increased at alkaline pH and both growth and nitrate uptake were maximal at pH 8-9. When the initial pH of culture medium was increased to pH 8 or 9, it was decreased to neutral upon bacterial growth and nitrate uptake. These results imply that the major factor mediating bacterial nitrate uptake is a nitrate/proton antiporter. The fact was supported by the effect of nitrate addition in the absence of nitrate, since the addition of nitrate greatly increased the nitrate uptake and rapidly decreased pH of media. 질소비료의 과량 시용에 따른 시설원예지 토양 중 염류집적은 다양한 작물에 염류장애를 유발하여 국내농업에 심각한 문제가 되고 있다. 염류의 주성분은 질산염으로 필요이상의 질산 이온을 제거하기 위하여 질산이온 흡수력이 크며, Enterobacter amnigenus GG0461로 동정된 토양세균을 시설원예 토양에서 분리하였다. 이 균주의 최적 생육 및 질산이온 흡수력을 조사하였을 때, GG0461 균주는 질산이온이 없는 조건에서 생육이 가능하나, 질산이온이 존재할 때 생육이 크게 촉진되었다. 또한, 염기성 조건에서 질산이온 흡수율이 증가하였으며, 성장과 질산이온 흡수 모두 pH 8-9에서 최대로 나타났다. 배지의 초기 pH를 8과 9로 조정하였을 때, 균주에 의하여 질산이온이 흡수 됨에 따라 배지의 pH는 중성으로 감소하였다. 이러한 결과는 질산이온 흡수를 위한 주된 인자가 nitrate/proton antiporter임을 의미한다. 이것은 질산이온이 없는 조건에서 질산이온의 첨가 효과인 질산이온 흡수의 급격한 증가와 빠른 배지의 pH 감소 사실로도 확인되었다.

탄닌과 EM 발효물을 첨가한 Struvite 결정에 의한 질소, 인 제거

김영규 ( Young-kyu Kim ),이미경 ( Mi-gyeong Lee ),라덕관 ( Deog-gwan Ra ) 한국환경기술학회 2014 한국환경기술학회지 Vol.15 No.5

탄닌과 EM 발효물을 첨가하여 형성된 struvite 결정에 의한 질소, 인의 제거에 대하여 검토하였다. 탄닌과 EM 발효물을 첨가한 struvite 결정의 형성 과정에서 pH가 높아짐에 따라 질소 제거율은 증가하였으며, 인 제거율은 큰 변화가 없었고, 마그네슘은 낮은 pH 조건에서 제거율이 크게 나타났다. 마그네슘 몰농도가 증가할수록 질소와 인의 제거도 증가하는 경향을 나타냈다. 또한 낮은 pH에서는 질소의 제거 몰량이 인의 제거 몰량보다 낮은 반면, 높은 pH에서는 반대의 경향을 나타내었다. 탄닌과 EM 발효물이 혼합된 마그네슘 용액으로 struvite 결정을 이루기 위해서는 초기에 0.96 mM의 마그네슘이 소모되었다. 그러나 pH 4.5이상에서는 마그네슘의 감소분에 대한 질소, 인의 제거량은 마그네슘 감소량에 비례해서 크게 증가하였다. Several experiments were performed to find out the characteristics of nitrogen and phosphorus removal capacity by struvite crystal, formed with tannin and EM(Effective Microorganisms) activated liquid. On the crystal formation in tannin and EM activated liquid solution, nitrogen removal efficiency was elevated in proportion to pH increasing, contrast to the unchangeable affection on phosphorus remove. Additionally, magnesium removal was more effective on low pH level. There was shown a tendency that the removal mole rate of nitrogen and phosphorus was proper to the initial magnesium quantity. And even though the nitrogen removal mole rate was much than phosphate one at low pH level, the removal rate of phosphorus was become larger one than nitrogen remove to high pH level, like as an opposite trend. As an initial condition, magnesium was needed at least 0.96 mM to make struvite crystal by using tannin and EM activated liquid complex solution. But on the condition of over the pH 4.5, the rate of nitrogen and phosphorous removal opposing to reduced magnesium was gradually increased, comparing the removed magnesium quantity.