Evaluation of triclosan toxic effects on the methanogenic activity

BACKGROUND: Triclosan (TCS) is an antimicrobial agent widely used in health care and consumer products. This compound is present in sludge of wastewater treatment plants (WWTPs), and because of its bactericidal characteristics, it can inhibit the methanogenic activity in anaerobic digestion (AD) technology. The aim of this study was to evaluate the toxic effects of TCS on the methanogenic activity. RESULTS: Batch anaerobic reactors were used with TCS concentrations of 7.8, 15.7, 23.5, and 31.4 mg/L. These assays consisted in three successive feedings (I, II, and III), wherein the sludge was exposed to each TCS concentration and volatile fatty acid (VFA) substrate. For evaluation of the residual sludge activity during feeding III, only VFA was used. The results showed that the increase in TCS concentrations correlated with the reduction in methane (CH4) production. In this case, the minimum values were achieved for TCS concentration of 31.4 mg/L with CH4 levels between 101.9 and 245.3 during feedings I, II, and III. Regarding the effect of TCS on VFA consumption, an inhibitory effect was detected for TCS concentrations of 23.5 and 31.4 mg/L, with concentrations of acetic, butyric, and propionic acids at the end of the assay (37 d) between 153.6 and 206.8, 62.5 and 60.1, and 93.4 and 110 mg/L, respectively. Regarding the removal of TCS during AD, these values were above 47%. Conclusion: TCS is an inhibitor of methanogenic activity with a decrease between 63 and 70% during the different feedings. The CH4 production was not recovered during feeding III, with inhibition percentages of 21­72%.

Establishment of in vitro methods for evaluation of induction and inhibition of human CYP450 enzymes by drugs / 药学学报

The aim of this study is to establish the in vitro methods for the study of induction and inhibition on CYP450 by drugs, and to validate the analytical method and incubation system. A method for the simultaneous determination of eight metabolites of seven subtypes of CYP450 enzymes probe substrates in human liver microsomes (HLM) was established and validated. The incubation system was optimized to confirm the incubation time and protein concentration of HLM, the enzyme activity of seven subtypes of CYP450 enzymes in HLM was determined, and the inhibition effects on each CYP450s were checked by positive controls. The method for the simultaneous determination of three metabolites of subtypes of CYP450 enzymes was established and validated in human primary cultured hepatocytes (HPCH) using the incubation medium. The enzyme activity of three subtypes of CYP450 enzymes in HPCH was determined, and the total RNA was extracted from HPCH after incubation. The expression of CYP450 enzymes were measured by Taqman fluorescence probe method. The induction effects on each CYP450s were examined using the positive controls. The established methods for the determination of metabolites of probe substrates were fully validated, and the results were conformed to the requirements of bioanalytical method validation. The induction and inhibition effects on each CYP450s were checked by positive controls. The established in vitro methods for the study of drug induction and inhibition on CYP450 were simple and reliable, which could be used in the investigation of enzyme induction or inhibition properties of new drug candidates and to evaluation the metabolic interactions of concomitant medication in clinical.

Inhibition Effect of Spinosin on Cytochrome P450 Enzymes from Human Liver Microsomes in vitro / 中国药房

OBJECTIVE:To study the inhibition effect of spinosin on 7 subtypes (CYP2B6,CYP2C8,CYP2C9,CYP2D6, CYP1A1,CYP2C19 and CYP3A4)of cytochrome P450(CYP450)enzymes from human liver microsomes in vitro. METHODS:Tak-ing 200.00,100.00,50.00,25.00,12.50,6.25,3.13,1.56,0.78,0.39 μmol/L spinosin and human liver microsomes for incuba-tion,using daktarin,bupropion,amodiaquine hydrochloride,diclofenac sodium,mephenytoin,dextromethorphan hydrobromide and midazolam as the specific probe drugs for above-mentioned 7 subtypes of CYP450 enzymes. UPLC-Q-TOF-MS was conducted to detect generation amount of 7 probe drug metabolites,and the half inhibitory concentration (IC50) of spinosin on 7 subtypes of CYP450 enzymes from human liver microsomes was calculated. RESULTS:IC50 of spinosin on 7 subtypes of CYP450 enzymes from human liver microsomes were 1714,1158,226.1,2288,80.59,101.1,1119 μmol/L,respectively,which were higher than 50μmol/L. CONCLUSIONS:Spinosin has no inhibition effect on above-mentioned 7 subtypes of CYP450 enzymes from human liver microsomes,with very low probability of inducing metabolic drug interactions.

Inhibition of berberine on organ anion transporters and its bidirectional trans-membrane transport / 药物评价研究

Objective To study the inhibition of berberine on organ anion transporters (OATs) and its bidirectional trans-membrane transport.Method The transgene cell lines of the organ anion transporters including OAT1,OAT2,OAT3,OAT4,OAT7,and URAT1 were constructed and selected by animal cell transgenic method mediated by transporter Lipo 3000.Wild type (WT) cells were used as control group,and activity of OATs was verified by adding their radiolabeled substrates and inhibitors.The inhibition of 100 μmol/L berberine on the transporters was investigated in vitro.The IC50 of berberine on URAT1 was also determined.The bidirectional transport of berberine was studied through the Caco-2 model.Result The results showed that 100 μmol/L berberine inhibited the activity of OAT1,OAT2,OAT3,OAT4,OAT7 and URAT1 to (70.48±4.23)％,(69.13±1.28)％,(72.12±3.28)％,(79.77±6.49)％,(69.51 ±5.99)％ and (38.4 ± 2.67)％ respectively,the IC50 of berberine to URAT 1 was 13.19 μmol/L,the Papp (A-B) of 50 μmol/L and 100 μmol/L berberine were separately 0.28 × 10-6 and 0.40 × 10-6 cm/s,and the effiux rates were separately 3.18 and 3.15.Conclusion Berberine shows a stronger inhibition to URAT1 compared to OAT1,OAT2,OAT3,OAT4 and OAT7.Berberine may be the substrate of some effiux transporters.This study provides theoretical basis for explaining the low bioavailability ofberberine and forecasting the possible drug-drug interaction.

Application of electronic tongue in pattern study about bitterness inhibition by hydroxypropyl-β-cyclodextrin / 中草药

Objective To study the bitterness inhibition law of hydroxypropyl-β-cyclodextrin (HP-β-CD) concentration (C) on the bitter compounds and bitter Chinese herbal medicine, and to explore the application of electronic tongue in this study. Methods Berberine, oxymatrine, Sophora flavescens, and Andrographis paniculata decoction were used as bitterness vectors to establish two models of bitterness inhibition law about ΔI-C and ΔIe-C, and to explore the prediction model of bitterness inhibition effect about ΔI-ΔIe, based on the oral taste evaluation results (ΔI) and electronic tongue information (ΔIe). Then, fitting precision and fitting goodness of the prediction model were evaluated with cross-validation and residual analysis. Results In this study, good Weibull model of bitterness inhibition pattern about ΔI-C were established for all the four bitterness vectors, the decision coefficient R2 are as followed: 0.999 6, 0.987 9, 0.996 4, and 0.998 4 (P < 0.01); The decision coefficient R2 of six (two sensors per vector) models of bitterness inhibition law about ΔIe-C of berberine, S. flavescens, and A. paniculata decoctions were as followed: 0.996 5, 0.991 6, 0.997 3, 0.989 3, 0.999 6, and 0.999 1 (P < 0.01); The decision coefficient R2 of six corresponding linear prediction models of bitterness inhibition effect about ΔI-ΔIe were as followed: 0.989 1, 0.968 3, 0.989 0, 0.982 0, 0.977 9, and 0.986 1 (P < 0.01); The correlation coefficient R calculated by correlation coefficient of six prediction models above were as followed: 0.986 0, 0.997 3, 0.988 4, 0.960 8, 0.980 2, and 0.983 9 (P < 0.01); No model was established for oxymatrine within the range of tested concentration in this research, as it didn’t respond to the four sensors with varied concentration. Conclusion Based on this method, the bitterness inhibition law of HP-β-CD with changed concentration was obtained. Prediction models based on HP-β-CD concentration or electronic tongue data were also established, they can be used to predict the relative bitterness inhibition effect. Part of the bitter compounds didn't response to the electronic tongue regularly, remain further research and development of electronic tongue technology.

Study on the Whitening activity and pathway of red eucommia herbs / 中国生化药物杂志

Objective To determine the impact of PEE with different ethanol concentration extract on the activity of tyrosinase in B16 melanoma and to explore the feasibility of PEE used as skin whitening agent make use of a model organism .Methods 30%, 50%, 70%, 95%, different concentration of ethanol reflux got four kinds of PEE alcohol extract, respectively.And selected the most active inhibition to mushroom tyrosinase ( PEE30、PEE50、PEE70、PEE95).The effect of extracts from the selected on B16 cell model was determined by MTS, NaOH splitting decomposition, L-DOPA oxidation progress.The change in protein expression level after ethanol extract of PEE was determined by Western bolt.Results The capacity of inhibition to mushroom tyrosinase in each concentration of PEE extraction, but PEE70 had the most active inhibition.When challenged with B16 cell model, PEE70 showed the capacity of decrease in tyrosinase activities and melanin synthesis (P<0.01) and had a does dependence ;it also decreased Tyrosinase and TRP-1 expression compared with control B16 cells.Conclusion These data support the idea that PEE can restrain melanogenesis, through its inhibitory effect on the activity of tyrosinase.

Growth inhibition effect of Rubus coreanus Miquel on Candida albicans / 대한구강보건학회지

OBJECTIVES: In this study, the growth inhibition effect of Rubus coreanus Miquel on Candida albicans (C. albicans) was observed. METHODS: The Rubus coreanus Miquel was extracted with 70% methanol and concentrated with a rotary evaporator. Antifungal effect of Rubus coreanus Miquel extract on C. albicans was determined by paper disc diffusion method and standard plate count method. Seven different concentrations (2, 4, 8, 15, 30, 60, 120 mg/ml) of the extract were tested by paper disc diffusion method. Two kinds of concentration (8, 60 mg/ml) of the extract were tested using standard plate count method on C. albicans with different incubating time (for 6, 12, 24 hours immediately after the cultivation). Morphological changes of C. albicans cells after exposure to the extract were observed with scanning electron microscopy (SEM) images. RESULTS: The Rubus coreanus Miquel extract showed an antifungal effect on C. albicans in 8, 15, 30, 60, 120 mg/ml of concentrations (P<0.05). The extract with 8 mg/ml of concentration showed about 30% of growth inhibition at 6 h and with 60 mg/ml it showed about 90% of growth inhibition at 24 h. SEM analysis showed damaged surfaces of C. albicans cells when treated with Rubus coreanus Miquel extract. CONCLUSIONS: The Rubus coreanus Miquel might have the potential as a nobel growth inhibitory agent against C. albicans that causes oral infection.

Potencial alelopático de Tropaeolum majus L. na germinação e crescimento inicial de plântulas de picão-preto / Allelophaty potential of Tropaeolum majus L on picão-preto seeds germination and initial seedling growth

Objetivou-se com este estudo avaliar o potencial alelopático de extratos metanólicos de folhas, flores e raízes de capuchinha (Tropaeolum majus L.) sobre a germinação de sementes e o crescimento inicial de plântulas de picão-preto. O extrato metanólico com melhor potencial de inibição foi submetido a particionamento, resultando nas frações hexânica, clorofórmica, acetato de etila e hidrometanólica e posterior caracterização pelo espectro de absorção na região do infravermelho (IV). O efeito alelopático foi avaliado sobre as sementes de picão-preto, as quais foram distribuídas sobre papel germitest umedecido com 2mL dos extratos e mantidas em germinador do tipo B.O.D. regulado a temperatura de 25°C e luz branca constante, sendo que as sementes imersas diretamente em água constituíram o tratamento controle. A avaliação da qualidade da semente foi realizada pelos testes de germinação e vigor (primeira contagem e comprimento de raiz primária e de hipocótilo das plântulas), em delineamento inteiramente ao acaso. O potencial alelopático das folhas de capuchinha foi maior em relação às demais partes da planta sobre a germinação das sementes, comprimento de hipocótilo e de raiz das plântulas de picão-preto. Estes efeitos podem estar associados à presença de grupos químicos polares, pois à medida que se aumentou a polaridade dos solventes detectou-se maior efeito inibitório sobre a germinação e o crescimento inicial de plântulas de picão-preto.

This research aimed to evaluate the metanolic extracts allelopathic potential from leaves, flowers and roots of capuchinha (Tropaeolum majus L.) on picão-preto seeds germination and initial seedling growth. The best inhibitor metanolic extract was fractioned, in hexanic, cloroformic, etil acetate and hidrometanolic fractions and it was characterized through absorption spectrum using mid-infrared. To evaluate the allelopathic effect of metanolic extracts and the fractions aftereffect; it was used picão-preto seeds distributed on 2ml extracts moistured paper maintained in B.O.D. germinator at 25°C and white constant light. Seeds sowed directly in water moistured germitest paper constituted the control. The allelopathic potential extracts were evaluated through the first count, final germination percentage, seedlings primary root and hypocotyl length (cm). The experiment was carried out DIC with three replications of 25 seeds. The capuchinha leaves showed allelopathic potential on picão-preto seeds germination, hypocotyl and seedlings primary root length. It was suggested that such effects are associated to the presence of polar chemical groups because the increase in the solvents polarity detected the major picão-preto germination and seedlings growth inhibition effect.

Application of Silver Nanoparticles for the Control of Colletotrichum Species In Vitro and Pepper Anthracnose Disease in Field

Pepper anthracnose caused by Colletotrichum species is one of the most important limiting factors for pepper production in Korea, its management being strongly dependent on chemicals. The aim of this work was to evaluate the possibilities of using silver nanoparticles instead of commercial fungicides. In this study, we evaluated the effect of silver nanoparticles against pepper anthracnose under different culture conditions. Silver nanoparticles (WA-PR-WB13R) were applied at various concentrations to determine antifungal activities in vitro and in the field. The application of 100 ppm concentration of silver nanoparticles produced maximum inhibition of the growth of fungal hyphae as well as conidial germination in comparison to the control in vitro. In field trials, the inhibition of fungi was significantly high when silver nanoparticles were applied before disease outbreak on the plants. Scanning electron microscopy results indicated that the silver nanoparticles caused a detrimental effect on mycelial growth of Colletotrichum species.

Inhibition Effects of Silver Nanoparticles against Powdery Mildews on Cucumber and Pumpkin

Powdery mildew is one of the most devastating diseases in cucurbits. Crop yield can decline as the disease severity increases. In this study, we evaluated the effect of silver nanoparticles against powdery mildew under different cultivation conditions in vitro and in vivo . Silver nanoparticles (WA-CV-WA13B) at various concentrations were applied before and after disease outbreak in plants to determine antifungal activities. In the field tests, the application of 100 ppm silver nanoparticles showed the highest inhibition rate for both before and after the outbreak of disease on cucumbers and pumpkins. Also, the application of 100 ppm silver nanoparticles showed maximum inhibition for the growth of fungal hyphae and conidial germination in in vivo tests. Scanning electron microscope results indicated that the silver nanoparticles caused detrimental effects on both mycelial growth and conidial germination.

The killing effect of pulsed electric fields(PEFs)with different frequencies on human ovarian carcinoma cell line SKOV3 in vitro and subcutaneously transplanted tumor in vivo / 中华物理医学与康复杂志

Objective To investigate acute cell damage and delayed inhibition effects by pulsed electric fields(PEFs)with different frequencies on human ovarian carcinoma cell line SKOV3 in vitro and in subcutaneous transplanted tumor of human SKOV3 in BALB/c nude mice,and evaluate the potential use of relatively higher frequency PEFs to reduce unpleasant sensations without decreasing therapeutic effects in clinical electrochemotherapy.Methods Firstly,SKOV3 cell suspension were exposed to PEFs with gradient increasing frequencies(1,60,1 000,5 000 Hz)and voltages(50,100,150,200,250,300,350,400 V),respectively.MTT assay was used to determine the acute cell damage.Then PEFs with gradient increasing frequencies(1,60,1 000,5 000 Hz)and fixed voltage (250 V)were applied to the subcutaneously transplanted tumor,in vivo antitumor assay was used to observe the delayed inhibition effect;histological changes were observed by light and electron microscope. Results The 1 Hz PEFs has similar cytotoxic effects with 5 kHz,and no significant difference of delayed tumor inhibition effect on subcutaneous transplanted tumor among all groups exposed to different frequencies of PEFs(P＞0.05).Histological observation showed acute damage in all exposed groups.and only in 5 kHz group was induced apoptotic effect observed.Conclusions PEFs with relatively higher frequency can achieve similar tumor killing effect with the low frequency PEFs,and it can also induce apoptosis.Relatively higher frequency PEFs show therapeutic potentials for reducing unpleasant sensations in clinical electrical treatment of tumor.

The Effect of Treponema Denticola and Treponema Lecithinolyticum on Periodontal Ligament Cells / 대한치주과학회지

This study was investigated to observe the effect of Treponema denticola(TDC) and Treponema lecithinolyticum(TLC) on cultured human periodontal ligament cells. Several experiments were performed including MTT test for the inhibition effect of cell proliferation, LDH test for the cytotoxicity , gelatin zymography for the gelatinase activation and observation of cell morphology change using the phase-contrast microscopy. The results were as follows. 1. The effect of concentration on cell proliferation with time showed an inhibitory effect at high concentration(150microgram/well) for TLC and at low concentration( 9.4microgram/well ) for TDC. 2. The effect of time on cell proliferation with concentration showed an inhibitory effect at 150microgram/well on 2-day incubation for TLC and at 9.4microgram/well on 2-day incubation for TDC. 3. The effect of heat-treated TDC and TLC on the inhibition of cell proliferation showed the difference in the heat-treated group compared to the non-heat treated group for TDC, whereas no difference was found for TLC. 4. The morphological changes which were observed from the phase-contrast microscopy showed the difference in the test group compared to the control group. The loss of spindle-like appearance, cell-to-cell detachment and inhibition of cell proliferation were observed. 5. There was no difference of the cytotoxicity effect between the test group and the control group in the LDH test. 6. The active form of progelatinase A with molecular weight 72kDa was activated in both TDC and TLC on the gelatin zymography. Regarding to the above results, TDC and TLC have an effect on periodontal ligament cells by playing an inhibitory role in cell proliferation and appears to activate progelatinase A which degrades type IV collagen.