Objective: One appealing strategy to overcome and prevent resistant problem is the use of combined two or more antibacterial substances. Lawsone methyl ether(LME) is the naphthoquinone found in the leaves of Impatiens...Objective: One appealing strategy to overcome and prevent resistant problem is the use of combined two or more antibacterial substances. Lawsone methyl ether(LME) is the naphthoquinone found in the leaves of Impatiens balsamina. The objective of this study is to determine the interaction of LME with some antibiotics(ampicillin, tetracycline, norfloxacin, and clotrimazole) and a natural compound, artocarpin against methicillin-resistant Staphylococcus aureus(MRSA), Candida albicans, and Trychophyton rubrum.Methods: A broth microdilution method was used to determine the minimum inhibition concentration(MIC). Synergistic effects were evaluated at their own MIC using the checkerboard method and time-kill assay.Results: LME showed moderate antibacterial activity against MRSA with MIC value of 15.6 μg/mL, and exhibited strong antifungal activities against T. rubrum and C. albicans with MIC values of 7.8 and 3.9 μg/m L,respectively. The interaction of LME with the natural compound artocarpin against MRSA produced a synergy with fractional inhibitory concentration index(FICI) value of 0.31, while the combination of LME and clotrimazole exhibited synergy against C. albicans and T. rubrum with FICI values of 0.38 and 0.24, respectively. The time-kill assays confirmed that the compounds in combination enhanced their antimicrobial activities against the resistant microorganisms with different degrees.Conclusion: LME in combination with clotrimazole exhibited synergy effect against C. albicans and T.rubrum. In combination with artocarpin, it showed synergy effect against MRSA.展开更多
We examined the possibility of developing a new risk assessment method for potentially hazardous chemicals by using mouse primary hepatocytes from acatalasemic mice (Csb) and the wild-type (Csa) as predictive model. C...We examined the possibility of developing a new risk assessment method for potentially hazardous chemicals by using mouse primary hepatocytes from acatalasemic mice (Csb) and the wild-type (Csa) as predictive model. Chemical-induced cytotoxicities, such as hydrogen peroxide and lawsone, a main hair dye ingredient of henna, were examined. We observed the differences in cell survival between the Csa and Csb in a dose-dependant manner after treatment with either hydrogen peroxide or lawsone, supporting the usefulness of this newly established method for hazard identification of oxidative chemicals in a risk assessment process. More chemicals will be tested to confirm the usefulness of this method for the preliminary screening of oxidative chemicals before animal experimentation.展开更多
The dye sensitized solar cells (DSSCs) have been extensively studied due to their low production cost and simple fabrication process. Dye co-sensitization broadens the absorption spectrum of the sensitizer;thus enhanc...The dye sensitized solar cells (DSSCs) have been extensively studied due to their low production cost and simple fabrication process. Dye co-sensitization broadens the absorption spectrum of the sensitizer;thus enhances light harvesting efficiency;and contributes to the improvement of the DSSCs overall efficiency. In this study we performed theoretical design of complex molecule (C45H32N2O4) through combination (esterification reaction) of the natural dye lawsone and synthetic metal free indoline dye D131. The excitation energies, vibration spectra, molecular structures, electronic absorption spectra and electron transitions in individual dyes and complex molecule were investigated using density functional theory (DFT) and time dependent density functional theory (TD-DFT) B3LYP5 methods, with 3-21G, 6-31G and 6-31G(d,p) basis sets. The UV-Vis absorption spectra of the individual dyes and their mixture in chloroform solution were measured using spectrophotometer. For the complex formation reaction, enthalpy, entropy and Gibbs free energy were calculated and the results indicated the reaction was endothermic and non-spontaneous. Electron density distribution of the frontier and adjacent molecular orbitals and energy levels alignment were used for analysis of the electronic spectra and mechanism of transitions. The results indicated that the designed complex molecule satisfied the requirements for good photosensitizer of DSSCs.展开更多
Biodegradable and absorptive wound dresses with antibacterial activity are in demand to accelerate wound heal-ing along with eliminating bacterial infection.Plant-derived naphthoquinones compounds such as lawsone have...Biodegradable and absorptive wound dresses with antibacterial activity are in demand to accelerate wound heal-ing along with eliminating bacterial infection.Plant-derived naphthoquinones compounds such as lawsone have shown sustained antibacterial functions to avoid development of bacterial resistance by reducing pH or attaching to bacterial proteins.Here the nanofibrous mats based on chitosan/polyethylene oxide(PEO)fibers containing various concentrations of lawsone(0,1,3,7,10%wt.)were fabricated by electrospinning for potential applications as wound dressing materials.The results exhibited that the chitosan/PEO/Lawsone nanofibers possess antibacterial activity toward Gram-negative and-positive bacteria.Surprisingly,the addition of lawsone in the proper amount into chitosan/PEO nanofibers not only introduced an antithetical property but also reduced the platform’s cytotoxicity,promoting cell viability of normal human fibroblast cells.Accordingly,the achieved data suggest the potential application of biocompatible nanofibrous mats as an antibacterial wound dressing material.展开更多
目的:探讨中草药散沫花中活性成分散沫花素(lawsone)在三阴性乳腺癌(triple negative breast cancer,TNBC)治疗中的应用前景。方法:选取2株TNBC细胞系MDA-MB-231和SUM1315作为研究对象,通过CCK-8实验、划痕实验、Transwell实验、平板克...目的:探讨中草药散沫花中活性成分散沫花素(lawsone)在三阴性乳腺癌(triple negative breast cancer,TNBC)治疗中的应用前景。方法:选取2株TNBC细胞系MDA-MB-231和SUM1315作为研究对象,通过CCK-8实验、划痕实验、Transwell实验、平板克隆、EdU以及细胞周期检测等实验探讨散沫花素对乳腺癌细胞的作用。结果:MDA-MB-231和SUM1315的72 h半数抑制浓度(IC50)分别为249.87μmol/L和158.34μmol/L,散沫花素能明显抑制乳腺癌细胞迁移、侵袭及增殖,同时能延长乳腺癌细胞周期的G1期。结论:散沫花素可能通过抑制乳腺癌细胞迁移、侵袭及增殖来影响乳腺癌的发生发展。展开更多
2Hydroxy1,4napthoquinone(lawsone)natural redorange dye was extracted from fresh henna(Lawsonia inermis)leaves in an alkaline media.The lawsonesurfactant solubilization constants(KLS)were calculated for the first time ...2Hydroxy1,4napthoquinone(lawsone)natural redorange dye was extracted from fresh henna(Lawsonia inermis)leaves in an alkaline media.The lawsonesurfactant solubilization constants(KLS)were calculated for the first time by using cationic cetyltrimethylammonium bromide(CTAB)and anionic sodium dodecyl sulphate(SDS).The standard free energy,concentration of solubilized lawsone and number of lawsone molecules solubilized into micelles were calculated and discussed.Surface excess,minimum surface area per molecule,surface pressure,free energy(adsorption and aggregation)and equilibrium constants of different states were determined from tensiometry.Different metal ions(Ag^(+),Co^(2+),Cu^(2+),Ni^(2+),Fe^(3+),Zn^(2+)and Al^(3+)were used to determine the complex forming ability with lawsone.Out of these,Ag+ions have strong binding capacity with lawsone.The adsorption of lawsone on the surface of glass with silver ions in presence of CTAB was also observed at pH>9.0.The pseudofirst,secondorder kinetic equation,intraparticles diffusion and Elovich models were used to determine the kinetics of lawsone adsorption onto the surface of glass and a probable mechanism has been discussed.Lawsone adsorption followed secondorder kinetic equation(k_(2)=0.019 g·mg^(1)·min^(1)).展开更多
基金supported by The Thailand Research Fund (Grant No. DBG6180031)
文摘Objective: One appealing strategy to overcome and prevent resistant problem is the use of combined two or more antibacterial substances. Lawsone methyl ether(LME) is the naphthoquinone found in the leaves of Impatiens balsamina. The objective of this study is to determine the interaction of LME with some antibiotics(ampicillin, tetracycline, norfloxacin, and clotrimazole) and a natural compound, artocarpin against methicillin-resistant Staphylococcus aureus(MRSA), Candida albicans, and Trychophyton rubrum.Methods: A broth microdilution method was used to determine the minimum inhibition concentration(MIC). Synergistic effects were evaluated at their own MIC using the checkerboard method and time-kill assay.Results: LME showed moderate antibacterial activity against MRSA with MIC value of 15.6 μg/mL, and exhibited strong antifungal activities against T. rubrum and C. albicans with MIC values of 7.8 and 3.9 μg/m L,respectively. The interaction of LME with the natural compound artocarpin against MRSA produced a synergy with fractional inhibitory concentration index(FICI) value of 0.31, while the combination of LME and clotrimazole exhibited synergy against C. albicans and T. rubrum with FICI values of 0.38 and 0.24, respectively. The time-kill assays confirmed that the compounds in combination enhanced their antimicrobial activities against the resistant microorganisms with different degrees.Conclusion: LME in combination with clotrimazole exhibited synergy effect against C. albicans and T.rubrum. In combination with artocarpin, it showed synergy effect against MRSA.
文摘We examined the possibility of developing a new risk assessment method for potentially hazardous chemicals by using mouse primary hepatocytes from acatalasemic mice (Csb) and the wild-type (Csa) as predictive model. Chemical-induced cytotoxicities, such as hydrogen peroxide and lawsone, a main hair dye ingredient of henna, were examined. We observed the differences in cell survival between the Csa and Csb in a dose-dependant manner after treatment with either hydrogen peroxide or lawsone, supporting the usefulness of this newly established method for hazard identification of oxidative chemicals in a risk assessment process. More chemicals will be tested to confirm the usefulness of this method for the preliminary screening of oxidative chemicals before animal experimentation.
文摘The dye sensitized solar cells (DSSCs) have been extensively studied due to their low production cost and simple fabrication process. Dye co-sensitization broadens the absorption spectrum of the sensitizer;thus enhances light harvesting efficiency;and contributes to the improvement of the DSSCs overall efficiency. In this study we performed theoretical design of complex molecule (C45H32N2O4) through combination (esterification reaction) of the natural dye lawsone and synthetic metal free indoline dye D131. The excitation energies, vibration spectra, molecular structures, electronic absorption spectra and electron transitions in individual dyes and complex molecule were investigated using density functional theory (DFT) and time dependent density functional theory (TD-DFT) B3LYP5 methods, with 3-21G, 6-31G and 6-31G(d,p) basis sets. The UV-Vis absorption spectra of the individual dyes and their mixture in chloroform solution were measured using spectrophotometer. For the complex formation reaction, enthalpy, entropy and Gibbs free energy were calculated and the results indicated the reaction was endothermic and non-spontaneous. Electron density distribution of the frontier and adjacent molecular orbitals and energy levels alignment were used for analysis of the electronic spectra and mechanism of transitions. The results indicated that the designed complex molecule satisfied the requirements for good photosensitizer of DSSCs.
基金supported by the Research and Technology Deputy of the Hamadan University of Medical Sciences(Grant number 9902231097).
文摘Biodegradable and absorptive wound dresses with antibacterial activity are in demand to accelerate wound heal-ing along with eliminating bacterial infection.Plant-derived naphthoquinones compounds such as lawsone have shown sustained antibacterial functions to avoid development of bacterial resistance by reducing pH or attaching to bacterial proteins.Here the nanofibrous mats based on chitosan/polyethylene oxide(PEO)fibers containing various concentrations of lawsone(0,1,3,7,10%wt.)were fabricated by electrospinning for potential applications as wound dressing materials.The results exhibited that the chitosan/PEO/Lawsone nanofibers possess antibacterial activity toward Gram-negative and-positive bacteria.Surprisingly,the addition of lawsone in the proper amount into chitosan/PEO nanofibers not only introduced an antithetical property but also reduced the platform’s cytotoxicity,promoting cell viability of normal human fibroblast cells.Accordingly,the achieved data suggest the potential application of biocompatible nanofibrous mats as an antibacterial wound dressing material.
文摘目的:探讨中草药散沫花中活性成分散沫花素(lawsone)在三阴性乳腺癌(triple negative breast cancer,TNBC)治疗中的应用前景。方法:选取2株TNBC细胞系MDA-MB-231和SUM1315作为研究对象,通过CCK-8实验、划痕实验、Transwell实验、平板克隆、EdU以及细胞周期检测等实验探讨散沫花素对乳腺癌细胞的作用。结果:MDA-MB-231和SUM1315的72 h半数抑制浓度(IC50)分别为249.87μmol/L和158.34μmol/L,散沫花素能明显抑制乳腺癌细胞迁移、侵袭及增殖,同时能延长乳腺癌细胞周期的G1期。结论:散沫花素可能通过抑制乳腺癌细胞迁移、侵袭及增殖来影响乳腺癌的发生发展。
基金the Deanship of Scientific Research(DSR),King Abdulaziz University,Jeddah,grant No.(G:255-2471440).
文摘2Hydroxy1,4napthoquinone(lawsone)natural redorange dye was extracted from fresh henna(Lawsonia inermis)leaves in an alkaline media.The lawsonesurfactant solubilization constants(KLS)were calculated for the first time by using cationic cetyltrimethylammonium bromide(CTAB)and anionic sodium dodecyl sulphate(SDS).The standard free energy,concentration of solubilized lawsone and number of lawsone molecules solubilized into micelles were calculated and discussed.Surface excess,minimum surface area per molecule,surface pressure,free energy(adsorption and aggregation)and equilibrium constants of different states were determined from tensiometry.Different metal ions(Ag^(+),Co^(2+),Cu^(2+),Ni^(2+),Fe^(3+),Zn^(2+)and Al^(3+)were used to determine the complex forming ability with lawsone.Out of these,Ag+ions have strong binding capacity with lawsone.The adsorption of lawsone on the surface of glass with silver ions in presence of CTAB was also observed at pH>9.0.The pseudofirst,secondorder kinetic equation,intraparticles diffusion and Elovich models were used to determine the kinetics of lawsone adsorption onto the surface of glass and a probable mechanism has been discussed.Lawsone adsorption followed secondorder kinetic equation(k_(2)=0.019 g·mg^(1)·min^(1)).
