• Title/Summary/Keyword: Alkaline stress

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Studies on Rheological Characterizaiton of Rhamsan Gum Produced by Alcaligenes -comparative studies on rheological Characterization of Rhamsan and Xanthangum- (Alcaligenes에 의해서 생성된 Rhamsan Gum의 리올리지 특성에 관한 연구)

  • Lee, Im-Seon;Kim, Mi-Ok;Koo, Sung-Ja
    • Korean journal of food and cookery science
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    • v.8 no.2
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    • pp.155-163
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    • 1992
  • Rhamsan gum produced by Alcaligenes was rheologically characterized, and compared to that of xanthan gum. The rheological properties were derermined from the change in the value of intrinsic viscosity with pH and salt concentration. at the range of pH 2~11 and salt concentration of 0~1.0 M KCl, the intrinsic viscosties of rhanisan gum were in the range of 8.2 to 36.2 dl/g and those of xanthan gum 8.19 to 44 dl/g. In the absence of salt, the intrinsic viscosity of rhamsan gum and Xanthan gum increased as the pH of solution increased up to neutral pH, and then decreased at alkaline pH. The intrinisc viscosities of rhamsan and anthan gum were not affec6ted by the increment of salt concentration. the chain stiffness paramenter for the rhamsan gum was 0.016. The overlap paramoeters of rhamsan and xanthan gum were 0.025 and 0.022 g/dl, respectively. rhamsan and xanthan gum were shear rate dependent or pseudoplastic. The yield stress of rhamsan gum increased slightly, but the shear index decreased as the concentration increased. The apparent viscosityes of rhamsan and xanthan gum decreased as the temperature increased. The salt effect of divalent cations (calcium, magnesium) was lower than monovalent cations (sodium, potassium).

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Effects of Polysaccharide Ginsan from Panax ginseng on Liver Function

  • Song, Jie-Young;Medea-Akhalaia;Alexander-Platonov;Kim, Hyung-Doo;Jung, In-Sung;Han, Young-Soo;Yun, Yeon-Sook
    • Archives of Pharmacal Research
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    • v.27 no.5
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    • pp.531-538
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    • 2004
  • Ginsan, a polysaccharide isolated from Panax ginseng, has been shown to be a potent immunomodulator, producing a variety of cytokines such as TNF-a, IL-1$\beta$, IL-2, IL-6, IL-12, IFN-${\gamma}$ and GM-CSF, and stimulating lymphoid cells to proliferate. In the present study, we analyzed some immune functions 1$^{st}$-5$^{th}$ days after ginsan i.p. injection, including the level of non-protein thiols (NPSH) as antioxidants, heme oxygenase (HO) activity as a marker of oxidative stress, zoxazolamine-induced paralysis time and level of hepatic cytochrome P-450 (CYP450) as indices of drug metabolism system, and activities of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), total bilirubin, and albumin level as indicators of hepatotoxicity. Ginsan in the dose of 100 mg/kg caused marked elevation (1.7-2 fold) of HO activity, decrease of total CYP450 level (by 20-34%), and prolongation of zoxazolamine-induced paralysis time (by 65-70%), and showed some differences between male and female mice. Ginsan treatment did not seem to cause hepatic injury, since serum AST, ALT, and ALP activities and levels of total bilirubin and albumin were not changed.d.

Effect of Lead Concentration on Surface Oxide Formed on Alloy 600 in High Temperature and High Pressure Alkaline Solutions (고온, 고압 알칼리 수용액에서의 Alloy 600 산화막 특성에 미치는 납 농도 영향)

  • Kim, Dong-Jin;Kim, Hyun Wook;Moon, Byung Hak;Kim, Hong Pyo;Hwang, Seong Sik
    • Corrosion Science and Technology
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    • v.11 no.3
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    • pp.96-102
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    • 2012
  • Outer diameter stress corrosion cracking (ODSCC) has occurred for Alloy 600 (Ni 75 wt%, Cr 15 wt%, Fe 10 wt%) as a heat exchanger tube of the steam generator (SG) in nuclear power plants (NPP) during long term operation. Among many causes for SCC, lead (Pb) is known to be one of the most deleterious species in the secondary system. In the present work, the oxide formed on Alloy 600 was characterized as a function of the PbO content in 0.1 M NaOH at $315^{\circ}C$ by using an electrochemical impedance spectroscopy (EIS), a transmission electron microscopy (TEM), equipped with an energy dispersive x-ray spectroscopy (EDS). The oxide property was analyzed in view of SCC susceptibility.

Reference Values of Whole Blood Viscosity and Its Correlation with Hematology and Serum Chemistry in Beagle Dogs

  • Koh, Jun;Lee, Dong-bin;Lee, Dong Han;Kim, Nam Soo
    • Journal of Veterinary Clinics
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    • v.35 no.3
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    • pp.77-82
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    • 2018
  • The aim of this study was to measure whole blood viscosity (WBV) and then to establish its reference values and identify correlation between WBV and hematology or serum chemistry in beagle. The experiment was made up of 82 healthy beagle dogs. Jugular vein blood samples (10 ml) were collected. WBV (cP) measured within 4 hours after collection by U-shaped scanning capillary-tube viscometer ($BVD-PRO1^{(R)}$) which is capable of measuring yield stress and viscosity of whole blood continuously over a wide range of shear rates from $1s^{-1}$ to $1000s^{-1}$ is new type of capillary tube viscometer and calculates viscosity using Casson fluid model. Measured values of WBV, Complete blood cell count, serum chemistry were analyzed by RM-ANOVA test. Mean diastolic and systolic WBV (cP) were $29.032{\pm}6.137$ and $4.528{\pm}0.865$. Bodyweight (BW), Red blood cell count (RBC), Hemoglobin (HGB), Hematocrit (HCT), Alkaline phosphatase (ALP), Cholestetol (CHOL), Total protein (TP), Globulin, Chloride (Cl), Fibrinogen, were statistically correlated with WBV over whole range of shear rates (p < 0.05). This study newly evaluated reference values of WBV by U-shaped viscometer in beagle. Correlation between WBV and BW, RBC, HGB, HCT, ALP, CHOL, TP, Globulin, Cl, Fibrinogen was presented.

Antigenotoxic Effects of Satureja hortensis L. on Rat Lymphocytes Exposed to Oxidative Stress

  • Mosaffa Fatemeh;Behravan Javad;Karimi Gholamreza;Iranshahi Mehrdad
    • Archives of Pharmacal Research
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    • v.29 no.2
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    • pp.159-164
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    • 2006
  • The protective properties of Satureja hortensis L. on the rat lymphocytes DNA lesions were tested. Lymphocytes were isolated from blood samples taken from healthy rats. DNA breaks and resistance to $H_{2}O_{2}$-induced damage were measured with the comet assay. Rat lymphocytes were incubated in S. hortensis ethanolic extract (SHE) (0.05, 0.1, 0.5, 1.0, and 2.5 mg/mL), essential oil (SHEO)(0.05, 0.1, 0.5, 1.0, and 2.5 ${mu}L/mL$), $H_{2}O_{2}$ (50, 100, and 200 ${\mu}M$), a combination of $H_{2}O_{2}$ (200 mM) with either SHE (1.0, 2.5 mg/mL) or SHEO (1.0, 2.5 ${\mu}L/mL$) at $4^{\circ}C$ for 30 min, and the extent of DNA migration was measured using a single-cell microgel electrophoresis technique under alkaline conditions. Treatment of rat lymphocytes with SHE or SHEO resulted in significant reduction of $H_{2}O_{2}$-induced DNA damage compared to controls. SHE exhibited a significant (P<0.01) inhibitory effect on oxidative DNA damage at 2.5 mg/mL. SHEO (1.0 and 2.5 ${\mu}L/mL$) also showed significant inhibitory effects (P<0.01) on $H_{2}O_{2}$ induced chromosomal damage. In conclusion both the ethanolic extract and the essential oil of the plant reversed the oxidative damage to rat lymphocytes induced by hydrogen peroxide.

Fed-batch Cultivation of Escherichia coli YK537 (pAET-8) for Production of phoA Promoter-controlled Human Epidermal Growth Factor

  • Wang Yonggang;Du Peng;Gan Renbao;Li Zhimin;Ye Qin
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.10 no.2
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    • pp.149-154
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    • 2005
  • Secretion of the expressed heterologous proteins can reduce the stress to the host cells and is beneficial to their recovery and purification. In this study, fed-batch cultures of Escherichia coli YK537 (pAET-8) were conducted in a 5-L fermentor for the secretory production of human epidermal growth factor (hEGF) whose expression was under the control of alkaline phosphatase promoter. The effects of feeding of glucose and complex nitrogen sources on hEGF production were investigated. When the fed-batch culture was conducted in a chemically de-fined medium, the cell density was 9.68 g/L and the secreted hEGF was 44.7 mg/L in a period of 60 h. When a complex medium was used and glucose was added in pH-stat mode, the secreted hEGF was improved to 345 mg/L. When the culture was fed with glucose at a constant specific rate of $0.25\;gg^{-1}h^{-1}$, hEGF reached 514 mg/L. The effects of adding a solution containing yeast extract and tryptone were further studied. Different rate of the nitrogen source feeding resulted in different levels of phosphate and acetic acid formation, thus affected hEGF expression. At the optimal feeding rate, hEGF production achieved 686 mg/L.

The Preventive Effects of Standardized Extract of Zataria multiflora and Carvacrol on Acetaminophen-Induced Hepatotoxicity in Rat - Zataria multiflora and Carvacrol and Hepatotoxicity -

  • Mohebbati, Reza;Paseban, Maryam;Beheshti, Farimah;Soukhtanloo, Mohammad;Shafei, Mohammad Naser;Rakhshandeh, Hasan;Rad, Abolfazl Khajavi
    • Journal of Pharmacopuncture
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    • v.21 no.4
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    • pp.249-257
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    • 2018
  • Objectives: The hepatotoxicity induced by Acetaminophen (AAP) mostly mediated by effect on oxidative stress parameters. The Zataria multiflora (Z.M) is an herbal medicine with well-known antioxidant effect. The aim of this study is investigation of preventive effects of Z.M and Carvacrol (CAR) on AAP-induced hepatotoxicity in rats. Methods: Rats were randomly divided into four groups including: 1) Control, 2) Acetaminophen (AAP), 3) and 4) CAR. The saline, Z.M (200 mg/kg) and CAR (20 mg/kg) were administrated orally for 6 days, after that AAP (600 mg/kg) was administrated in the $7^{th}$ day. Blood sampling was performed on the first and last days. Also, the liver tissue was removed for evaluation of Malondyaldehide (MDA), Thiol content, Superoxide dismutase (SOD) and Catalase (CAT). Total Protein (tPro), Glutamic Oxaloacetic Transaminase (GOT), Glutamic Pyruvic Transaminase (GPT) and Alkaline Phosphatase (ALP) in liver tissue were evaluated. The changes (${\Delta}$) of enzymes activities were presented. Results: The ${\Delta}GOT$, ${\Delta}GPT$ and ${\Delta}ALP$ in CAR group significantly decreased compared to AAP group (P < 0.01 to P < 0.001) and ${\Delta}GPT$ in Z.M group was significantly reduced in comparison with AAP group (P < 0.05). Also, MDA, Thiol, SOD and CAT levels in treated groups were attenuated compared to AAP group (P < 0.05 to P < 0.001). Conclusion: Z.M and CAR have a powerful hepatoprotective effect. CAR is more effective than Z.M. Based on the results. Z.M and CAR could be potent supplementary agents against hepatotoxicity of AAP in patients.

Antioxidaitve and Differentiation Effects of Artemisia capillaris T. Extract on Hydrogen Peroxide-induced Oxidative Damage of MC3T3-E1 Osteoblast Cells (사철쑥(Artemisia capillaris T.) 추출물의 항산화 활성 및 H2O2로 산화적 스트레스를 유도한 조골세포의 활성과 분화에 미치는 영향)

  • Seo, Jee-Eun;Hwang, Eun-Sun;Kim, Gun-Hee
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.40 no.11
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    • pp.1532-1536
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    • 2011
  • In this study, the antioxidative activity of Artemisia capillaris T. extract on the proliferation and differentiation of MC3T3-E1 cells under $H_2O_2$-induced oxidative stress was investigated in order to determine its protective effect against oxidative stress as well as its availability as an antioxidant material related to treatment of bone diseases. As a result, the total polyphenol content of A. capillaris extract was 90.10 mg/g, whereas the flavonoid content was 4.45 mg/g. A. capillaris extract increased proliferation of MC3T3-E1 cells under $H_2O_2$-induced oxidative stress, and also increased the proliferation of differentiated osteoblast cells under oxidative stress. In addition, two differentiation markers, alkaline phosphatase activity and mineralization level, in A. capillaris extract tended to increase. These results indicate that A. capillaris extract suppresses the damage to osteoblasts caused by oxidative stress, which demonstrates its availability as an antioxidant material for preventing bone diseases.

Mechanical Properties of Alkali-Activated Slag-Based Concrete Using Lightweight Aggregates (경량골재를 사용한 알칼리 활성 슬래그 콘크리트의 역학적 특성)

  • Yang, Keun-Hyeok;Oh, Seung-Jin;Song, Jin-Gyu
    • Journal of the Korea Concrete Institute
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    • v.20 no.3
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    • pp.405-412
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    • 2008
  • Six alkali-activated (AA) concrete mixes were tested to explore the significance and limitations of developing an environmental friendly concrete. Ground granulated blast-furnace slag and powder typed sodium silicate were selected as source material and an alkaline activator, respectively. The main parameter investigated was the replacement level of lightweight fine aggregate to the natural sand. Workability and mechanical properties of lightweight AA concrete were measured: the variation of slump with time, the rate of compressive strength development, the splitting tensile strength, the moduli of rupture and elasticity, the stress-strain relationship, the bond resistance and shrinkage strain. Test results showed that the compressive strength of lightweight AA concrete sharply decreased when the replacement level of lightweight fine aggregate exceeded 30%. In particular, the increase in the discontinuous grading of lightweight aggregate resulted in the deterioration of the mechanical properties of concrete tested. The measured properties of lightweight AA concrete were also compared, wherever possible, with the results obtained from the design equations specified in ACI 318-05 or EC 2, depending on the relevance, and the results predicted from the empirical equations proposed by Slate et al. for lightweight ordinary Portland cement concrete. The stress-strain curves of different concrete were compared with predictions obtained from the mathematical model proposed by Tasnimi. The measured mechanical properties of lightweight AA concrete generally showed little agreement with the predictions obtained from these equations.

Protective Efficacy of Alpha-lipoic Acid against AflatoxinB1-induced Oxidative Damage in the Liver

  • Li, Y.;Ma, Q.G.;Zhao, L.H.;Guo, Y.Q.;Duan, G.X.;Zhang, J.Y.;Ji, C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.27 no.6
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    • pp.907-915
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    • 2014
  • Alpha-lipoic acid (${\alpha}$-LA) is not only involved in energy metabolism, but is also a powerful antioxidant that can protect against hepatic oxidative stress induced by some drugs, toxins, or under various physiological and pathophysiological conditions. Here, we investigated the effect of ${\alpha}$-LA against liver oxidative damage in broilers exposed to aflatoxin $B_1$ ($AFB_1$). Birds were randomly divided into four groups and assigned different diets: basal diet, 300 mg/kg ${\alpha}$-LA supplementation in basal diet, diet containing 74 ${\mu}g/kg$ $AFB_1$, and 300 mg/kg ${\alpha}$-LA supplementation in diet containing 74 ${\mu}g/kg$ $AFB_1$, for 3 weeks. The results revealed that the addition of 300 mg/kg ${\alpha}$-LA protected against the liver function damage of broilers induced by chronic low dose of $AFB_1$ as estimated by a significant (p<0.05) change in levels of plasma total protein, albumin, alkaline phosphatase and the activities of liver glutamic-oxalacetic transaminase and glutamic-pyruvic transaminase. The histopathological analysis also showed that liver tissues were injured in the $AFB_1$ diet, but this effect was alleviated by the addition of 300 mg/kg ${\alpha}$-LA. Additionally, $AFB_1$ induced a profound elevation of oxidative stress in birds, as indicated by an increase in malondialdehyde level, a decrease in glutathione peroxidase activity and a depletion of the glutathione content in the liver. All of these negative effects were inhibited by treatment with ${\alpha}$-LA. Our results suggest that the inhibition of $AFB_1$-induced excess production of lipid peroxides and the maintenance of intracellular antioxidant status may play important roles in the protective effects of ${\alpha}$-LA against $AFB_1$-induced oxidative damage in the liver.