• Title/Summary/Keyword: Inhibition rate

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The Effect of Nonionic Surfactants on the Solubility and Biodegradation of PAHs in Soil Slurry (PAHs의 용해도와 생분해에 미치는 비이온계 계면활성제의 영향)

  • 박종섭;김인수
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 1998.11a
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    • pp.174-177
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    • 1998
  • The effects of surfactants affecting polycyclic Aromatic Hydrocarbon(PAHs) solubility and biodegradation in soil slurry were investigated. The critical micelle concentration(CMC) values of surfactants used in this study were 12.7mg/L(Brij 30), 13.4mg/L(Tween 80), 13.6mg/t(Triton X-100). The solubility of PAH increased as the Hydrophile-Lipophile Balance(HLB) value of surfactant decrease. At surfactant biodegradation and toxicity experiement using respirometer, Brij 30 did not show any toxic effect and substrate inhibition upon the level of 1.5g/L. Also, biodegradation of Brij 30 gave no reduction on the phenanthrene biodegradation rate. When the desorption rate of phenanthrene between sand and clay is compared, lower percentage of phenanthrene was desorbed at clay because of the larger surface aera and higher organic content of clay. At the biodegradation experiments of phenanthrene in soil slurry phase, more than 90% of initial phenanthrene adsorbed onto both sand and clay were biodegraded by phenanthrene- acclimated cultures.

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$\alpha$-Glucosidase Inhibition by Culture Broth of Streptomyces sp. NS15 (Streptomyces sp. NS15 배양액에 의한 $\alpha$-Glucosidase 저해)

  • 백남수;김영만
    • The Korean Journal of Food And Nutrition
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    • v.11 no.6
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    • pp.640-646
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    • 1998
  • For the production of nonprotein $\alpha$-glucosidase inhibitor from the Streptomyces sp. NS15 strain, effects of initial optimum pH, nitrogen sources, carbon sources, cationic metal ions, agitation speed and aeration rate were investigated. Initial optimum pH of medium was 7.0. The most effective nitrogen and carbon sources were soybean meal 2.0%(w/v) and glucose 1.6%(w/v), respectively. The cationic metal ins had no stimulating effect on inhibitory activity of $\alpha$-glucosidase except Fe2+. Agitation speed and aeration rate were effective at 400rpm and 1vvm, respectively. In the jar-fermenter cultivation for 4 days under optimal culture conditions, the culture broth showed the inhibitory acitivity of 3,200units/ml, which is 25 times higher than that of basic medium (CYM) for porcine intestinal $\alpha$-glucosidase. The inhibitory activity of $\alpha$-glucosidase reached about 3,200units/ml after 4 days of cultivation and decreased gradually for a further two days.

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Study of Antimicrobial Effects of Different Types of Glycyrrhiza Extracts by Microcalorimetry

  • Wei, Ting;Lin, Guimei;Liu, Lian;Zhao, Zhongxi
    • Bulletin of the Korean Chemical Society
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    • v.35 no.8
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    • pp.2460-2464
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    • 2014
  • Recently studies indicate that the microcalorimetry is a suitable measurement for metabolic activities of organisms by recording the rate of heat outputs. In this work, we investigated the growth thermogenic curves of Escherichia coli (E. coli) affected by three kinds of Glycyrrhiza extracts by microcalorimetry. The power-time and exponential phase power-time curves of the E. coli growth at various concentrations of extracts were generated. The kinetic parameters such as the growth rate constants (C), maximum power outputs (Pm), peak times (Tm), and inhibition ratios were calculated and the relationships between Pm or Tm and C were established. Also, the clear correlations among the antimicrobial effects, Pm and C were obtained. The results revealed the Glycyrrhiza extracts had inhibitory activities towards E. coli while the Glycyrrhiza polysaccharides showed the most potent effects.

Simultanceous Saccharification and Fermentation of Cellulose for Lactic Acid Production

  • Yoon, Hyon-Hee
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.2 no.2
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    • pp.101-104
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    • 1997
  • Lactic acid production from ${\alpha}$-cellulose by simultaneous saccharification and fermentation (SSF) was studied. The cellulose was converted in a batch SSF using cellulase enzyme Cytolase CL to produce glucose sugar and Lactobacillus delbrueckii to ferment the glucose to lactic acid. The effects of temperature, PH, yeast extract loading, and lactic acid inhibition were studied to determine the optimum conditions for the batch processing. Cellulose was converted efficiently to lactic acid, and enzymatic hydrolysis was the rate controlling step in the SSF. The highest conversion rate was obtained at 46$^{\circ}C$ and pH 5.0. The observed yield of lactic acid from ${\alpha}$-cellulose was 0.90 at 72 hours. The optimum pH of the SSF was coincident with that of enzymatic hydrolysis. The optimum temperature of the SSF was chosen as the highest temperature the microoraganism could withstand. The optimum yeast extract loading was found to be 2.5g/L. Lactic acid was observed to be inhibitory to the microorganisms' activity.

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Antimicrobial Activity of Extracts from Aloe vera peel against Streptococcus mutans JC-2(I) (Aloe vera peel 추출물의 Streptococcus mutans JC-2에 대한 항균활성 (I))

  • 박정순;신용서;류일환;이갑상
    • The Korean Journal of Food And Nutrition
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    • v.13 no.2
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    • pp.139-145
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    • 2000
  • To separate anticaries and antiinflammation from Aloe vera peel, we investigated a inhibited effect of Streptococcus mutans JC-2 that was antibiosis, glucosyltransferase activity about aloe-emodin and barbaloin. Aloe-emodin and barbaloin had strong antibiosis activity against Streptococcus mutans JC-2, they were especially antibiosis effect to low growth and prolong lag phase at attachment concentration 100$\mu\textrm{g}$/mL. The reduction rate of a culture fluid became to lessen than the comparison group for aloe-emodin and barbaloin. The intracellular materials of Streptococcus mutans JC-2 were to leakage as much as attachment concentration addition of aloe-emodin and barbaloin but there was no significant difference membrane demage between two active substances. The activity of GTase was inhibited by aloe-emodin and barbaloin and their inhibition rate was respectively 99.8%, 98.4% at the attachment concentration 100$\mu\textrm{g}$/mL.

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Radiosensitizing and Antitumor Effect of the Seed of Benincasae hispida (동과자(冬瓜子)의 항암활성과 방사선에 대한 감작효과)

  • Choi, Hye-Ran;Lee, Keyong-Ho;Kim, Chang-Han
    • Korean Journal of Food Science and Technology
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    • v.35 no.3
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    • pp.479-482
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    • 2003
  • Radiosensitizing and antitumor effects of hot water extract derived from the seed of Benincasae hispida were investigated. The extract showed maximum survival rate of 21% at 0.1 g/kg against L1210 cells implanted in BDF1 mice. Radiosensitivity of human tumor cell line was evaluated through sulforhodamine assay. Inhibition rate of SK-OV-3 cells after 5 Gy radiation by Benincasae hispida seed extract at 2 mg/mL was 86%.

Inhibiton Activity and Charaterization of Lactic Acid Bacteria from Pig Feces (돼지분변으로부터 분리한 유산균주들의 헬리코박터 저해력과 항균활성 및 배양특성)

  • Moon, Ki-Hyuke;Park, Phun-Bum;Yoon, Jeong-Weon
    • KSBB Journal
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    • v.20 no.2 s.91
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    • pp.76-83
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    • 2005
  • Lactic acid bacteria were isolated from pig feces for probiotics. The six isolated strains were identified as Lactobacillus paracasei (Lp), Lactobacillus fermentum (Lf), Lactobacillus brevis (Lb), Lactobacillus plantarum (P1 , P2), and Pediococcus pentosaceus (P3) by its sugar utilization, morphological and physiological characteristics. Pl was showed largest antibacterial inhibition zone among the isolated strains. It was against Salmonella gallinarum 25mm, E. coli 20.5mm, Staphylococcus aures 24mm, and Pseudomonas aeruginosa 28mm by inhibitory zone, respectively. Lf was showed hyper acid tolerance, $80\%$ survival rate for 40 minutes, and P1, Lb showed hyper bile tolerance, $408\%,\;283\%$ survival rate for 9 hrs, respectively. Therefore the Lf, P1, and P2 strains were expected to probiotics.

Effect of Cimetidine Pretreatment on the Pharmacokinetics of Sulfisomidine Administered Intravenously in Rabbits (시메티딘이 설프이소미딘의 약물동태에 미치는 영향)

  • 이진환;최준식;범진필
    • YAKHAK HOEJI
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    • v.29 no.6
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    • pp.362-366
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    • 1985
  • These paper was attempted to investigate the mechanism of increased blood level of sulfisomidine by cimetidine pretreatment pharmacokinetically. Especially, effect of cimetidine pretreatment on both renal clearance and biliary clearance of sulfisomidine was studied in rabbits. The results are as follows. The blood level of sulfisomidine administered intravenously in dose of 25mg/kg was elevated significantly by cimetidine pretreatment. Relative bioavailability and biological half-life were increased significantly by cimetidine pretreatment. Overall elimination rate constant ($betha$) and distribution rate constant ($K_{13}$) of sulfisomidine were decreased significantly by cimetidine pretreatment. The renal and biliary clearance of sulfisomidine were decreased significantly compared with those of control rabbits by cimetidine pretreatment. The results may be also related to the inhibition of sulfisomidine metabolism enzyme activity or reduction of blood flow in the liver.

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A Study on the Biological Organic, Nitrogen and Phosphorus Removal in Sequencing Batch Biofilm Reactor (연속회분식 생물막 반응기(Sequencing Batch Biofilm Reactor)를 이용한 수중의 유기물, 질소 및 인의 동시 제거에 관한 연구)

  • 박민정;김동석
    • Journal of Environmental Health Sciences
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    • v.30 no.2
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    • pp.84-91
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    • 2004
  • Biological nutrient removal(BNR) from wastewater was performed by adopting various process configurations. The simultaneous biological organics, phosphorus and nitrogen removal of synthetic wastewater was investigated in a sequencing batch biofilm reactor (SBBR). The other reactor was operating as a reference, without biofilm being added. The cycling time in SBR and SBBR was adjusted at 12 hours and then certainly included anaerobic and aerobic conditions. Both systems has been operated with a stable total organic carbon(TOC), nitrogen and phosphorus removal performance for over 90 days. Average removal efficiencies of TOC and total nitrogen were 83% and 95%, respectively. The nitrification rate in SBR was higher than that in SBBR. On the contrary, the denitrification rate in SBBR was higher than that in SBR. The phosphorus release was occurred in SBBR, however, not in SBR because of the inhibition effect of NO$_3$$^{[-10]}$ .

Characterization of the ${\cdot}O_{2}^{-}$-Formation by Pyridine Nucleotide in Rat Hepatocytes

  • Kim, Ki-Sung
    • BMB Reports
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    • v.28 no.6
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    • pp.533-537
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    • 1995
  • The detection with lucigenin under physiological conditions is selective for ${\cdot} O_{2}^{-}$, for it can be accepted that lucigenin indicates actual intramembranal $\cdot O_{2}^{-}- formation$. Lucigenin chemiluminescence (CL) was elicited from the plasma membrane (PM) only by addition of reduced pyridine nucleotide. NADPH was preferred to NADH in PM and hepatocytes. This specificity was masked by $NAD(P)^+$ inhibition. The half maximum rate of CL increase was obtained with 1.5 ${\mu}m$ NADH or 55 ${\mu}m$ NADPH in hepatocytes and 6 ${\mu}m$ NADH or 30 ${\mu}m$ NADPH in plasma membranes. Measurement of these NADPH values required the presence of a NADPH-regenerating system. With NADPH the maximal rate obtained was 10 fold higher than with NADH. NADPH and NADH could produce CL when having access from either side of the membrane. They seemed to react with the identical acceptor because NADH-induced CL was also inhibited by $NADP^+$. The characteristics of ${\cdot}O_{2}^{-}-formation$ produced by pyridine nucleotide will be discussed.

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