To study the antioxidant constituents from the stems of Dendrobium nobile, and to discuss theft structure-activity relationship. Compounds were isolated from a 60% ethanolic extract by various chromatographic techniqu...To study the antioxidant constituents from the stems of Dendrobium nobile, and to discuss theft structure-activity relationship. Compounds were isolated from a 60% ethanolic extract by various chromatographic techniques and were identified by spectral analysis. The antioxidant activities of compounds were evaluated by DPPH free radical scavenging assay. Five phenanthrenes and four lignans were obtained from the active fractions ofD. nobile. Their structures were identified as fimbriatone （1）, confusarin （2）, flavanthrinin （3）, 2,5-dihydroxy-4,9-dimethoxyphenanthrene （4）, 3,7-dihydroxy-2,4-dimethoxyphenanthrene （5）, syringaresinol （6）, pinoresinol （7）, medioresinol （8） and lirioresinol-A （9）, respectively. Compounds 2 and 6 exhibited more potent DPPH scavenging activities than vitamin C. All the above compounds were reported from this plant for the first time, and compounds 3, 4 and 9 were reported for the first time from the genus of Dendrobiurn. For all phenanthrenes and lignans, an electron-donating methoxyl group in the ortho position to the phenolic hydroxyl group exhibits enhanced antioxidant activities.展开更多
Eleven 1-(1H-1,2,4-triazole)-2-(2,4-diflurophenyl)-3-(N-methyl-N-substituted benzylamino)-2-propanols were designed and synthesized, on the basis of the crystal structure of P450 cytochrome 14α-sterol demethylase(CYP...Eleven 1-(1H-1,2,4-triazole)-2-(2,4-diflurophenyl)-3-(N-methyl-N-substituted benzylamino)-2-propanols were designed and synthesized, on the basis of the crystal structure of P450 cytochrome 14α-sterol demethylase(CYP51) and the docking results of inhibitors to the active site of the enzyme. All title compounds were first by reported. Results of preliminary biological tests showed that most of title compounds exhibited activity against the seven common pathogenic fungi. Compound 11 showed best antifungal activity with broad antifungal spectrum and proved to be more active against Cryptococcus neoformans, Candida albicans, Microsporum lanosum and Trichophyton rubrum than ketoconazole. Compounds 3, 10 and 4 also had high activities.展开更多
Neutralizing antibodies are considered to be an important protective parameter used in HIV-1 vaccine evaluation. However, the exact role that neutralizing antibodies plays in controlling the disease progression of HIV...Neutralizing antibodies are considered to be an important protective parameter used in HIV-1 vaccine evaluation. However, the exact role that neutralizing antibodies plays in controlling the disease progression of HIV-1 infected peoples is still undetermined. In this paper, we compared the protective function of the neutralizing antibody response in the plasma from LTNP and TP against clade B and clade C pseudoviruses. No difference in the neutralizing activities between the plasma from LTNP and TP was found, which was consistent with the most recent reports. In addition, no correlations between the titer or breadth and CD4+ or viral load in HIV-1 infected individuals were found. The protective roles played by neutralizing antibodies in controlling disease progression of HIV-1 infected people need to be considered in a new viewpoint.展开更多
Salvianolic acid B(Sal B) is an active component of traditional Chinese medicine Salvia miltiorrhiza and is used to treat vascular diseases. To better understand its mechanism, the antioxidant capacities of Sal B was ...Salvianolic acid B(Sal B) is an active component of traditional Chinese medicine Salvia miltiorrhiza and is used to treat vascular diseases. To better understand its mechanism, the antioxidant capacities of Sal B was evaluated with human endothelial cells under oxidative stress. Human endothelial cells were pretreated with Sal B for 12 h followed by hydrogen peroxide for another 12 h. Production of reactive oxygen species (ROS), activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX), and concentration of glu-tathione were measured. Protective effect of Sal B on the endothelial cells from hydrogen peroxide-induced damage was observed, and ROS production in the cells was found significantly inhibited. Sal B remarkably enhanced the activities of antioxidant enzymes SOD, CAT and GPX. Furthermore, Sal B up-regulated the intracellular glu-tathione concentration. The results indicate that Sal B protected endothelial cells from oxidative stress by improving the redox status of the cells through enhancing the antioxidant enzyme activities and increasing the reductive glu-tathione concentration after the oxidative challenge.展开更多
The polyphenol content,antioxidant and antimicrobial activities of the extracts obtained by classical, ultrasonic and Soxhlet extractions from dry aerial parts of two Artemisia species(Artemisia vulgaris and Artemisia...The polyphenol content,antioxidant and antimicrobial activities of the extracts obtained by classical, ultrasonic and Soxhlet extractions from dry aerial parts of two Artemisia species(Artemisia vulgaris and Artemisia campestris)were compared.Ultrasound positively affected the yield of extractive substance and the kinetics of extraction,but the extract obtained by the classical extraction showed the highest antioxidant activities and contained higher total contents of phenolic compounds and flavonoids than the extracts obtained by two other extraction techniques.Both flavonoid aglycones(apigenin,quercetin,quercetin 3,3′-dimethyl ether)and flavonoid glycosides(rutin,hyperoside and kaempferol 3-rhamnoside)were identified by thin layer chromatograph(TLC)analysis in the extracts from both species.A.campestris extracts were richer in quercetin than A.vulgaris and its antimicrobial activity was also better than A.vulgaris.Extracts obtained from both species were found to be more effective on the tested yeasts than bacteria.The kinetics of the total extractive substances,such as phenolic,flavonoids and quercetin extraction,was successfully described by the model of unsteady-state diffusion.展开更多
To investigate into the mechanisms underlying the irreversible sterility induced by gossypol, we studied the relationship between its inhibitory action on acrosomal enzymes and its antifertility effect.As shown by our...To investigate into the mechanisms underlying the irreversible sterility induced by gossypol, we studied the relationship between its inhibitory action on acrosomal enzymes and its antifertility effect.As shown by our result, after exposure to gossypol (l.25-60 μg/ml) for 15 min. in vitro,the sperms' ability to penetrate bovine cervical mucus and the fertility rate were significantly reduced. Also, following administration of gossypol (12.5 mg/kg/day) for six weeks, the rate of fertilization in vitro by hamster sperm was significantly decreased. In the gossypol-treated group, extracts of testis sperm delayed dispersion of cumulus cells, suggesting inhibition of hyaluronidase and other acrosomal enzymes. Furthermore, the acrosin and arylsulfatase activities were shown to be markedly inhibited. Thus, a parallelism was displayed between the reduction of fertility and the decreasc in acrosin and arylsulfatase activities in epididymis sperms.Besides, the inhibition was reversible and was dosage-and durationdependent. In conclusion, the assay of acrosin activity might serve as a useful tool for monitoring the irreversible sterility induced by gossypol,展开更多
Functional properties of Talbina were used in ancient Arab for nutritional purpose. It was a meal made from barley flour and milk. The high antioxidant Talbina was formulated from whole flour of harley and oat, milk, ...Functional properties of Talbina were used in ancient Arab for nutritional purpose. It was a meal made from barley flour and milk. The high antioxidant Talbina was formulated from whole flour of harley and oat, milk, date palm syrup （debis） and date palm seeds. The chemical composition, organoleptic properties and antioxidant activity of high antioxidant Talbina were determined. Sensory evaluation of traditional and high antioxidant Talbina showed that the developed product Talbina was considered as good for overall acceptability of all panelists. Also, the formulated Talbina contains high values of antioxidants components and natural nutrients. The antioxidant activity of formulated Talbina containing barley or oat may be due to presence of phenolic compounds and proanthocyanidins in the barley and oat. Increasing the antioxidant activity of high antioxidant Talbina containing barley and oat may be due to the adding of dates palm seeds which contain very high values of phenolic compounds and other antioxidants components. Date palm seeds as well as barley and/or oat give high antioxidants components which protect cells from oxidative stress and help to reduce the risk of cancer and heart disease as well as natural anti-depressant. Moreover, increasing the antioxidant activity in the formulated Talbina may play a role for reducing power, radical scavenging activity and the lipid peroxidation inhibition. In conclusion, supplementation of traditional Talbina containing barley and/or oat with date palm syrup （debis） and date palm seeds can produce simple and healthy meal to provide a good source of daily dietary antioxidants and micronutrients.展开更多
Tetraphenyl-porphyrin iron （FeTPP） was chosen to sensitize Cr doped TiO2 （Cr-TiO2） nanoparticles, a novel multimodified photocatalyst FeTPP-Cr-TiO2 with excellent visible- light photocatalytic activity was success...Tetraphenyl-porphyrin iron （FeTPP） was chosen to sensitize Cr doped TiO2 （Cr-TiO2） nanoparticles, a novel multimodified photocatalyst FeTPP-Cr-TiO2 with excellent visible- light photocatalytic activity was successfully synthesized. The FeTPP-Cr-TiO2 microspheres were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electronic microscopy, X-ray photoelectron spectroscopy, UV-Vis diffuse reflectance spectra and N2 adsorption-desorption isotherms. The photocatalytic activity of FeTPP-Cr-TiO2 was evaluated by degradations of methylene blue in aqueous solution under irradiation with Xe lamp （150 W）. The results showed that the FeTPP-Cr-TiO2 multimodified photocatalyst was anatase phase with high specific surface area （74.7 m^2/g）, and exhibited higher photocatalytic degradation efficiency than Cr-TiO2 and FeTPP-TiO2. The photocatalytic degradations of three quinolone antibiotics （lomefioxacin, norfioxacin, and ofioxacin） were further estimated for the feasibility of practical application of catalyst in wastewater treatment. It is desirable that photodegradation of antibiotics with FeTPP-Cr-TiO2 achieved pretty high degradation rates and all followed the pseudo first-order reaction model, and the rate constants k of 3.02×10^-2, 2.81×10^-2, and 3.86×10^-2 min-1 and the half-lifes t1/2 of 22.9, 24.6, and 17.9 min were achieved respectively.展开更多
Antioxidant efficiency was studied in fresh edible algae： Cladophora, Microspara and Nostochopsis spp. from Nan River, Nan province. The samples were collected from Pua and Tha-Wang-Pha district, studied antioxidant ...Antioxidant efficiency was studied in fresh edible algae： Cladophora, Microspara and Nostochopsis spp. from Nan River, Nan province. The samples were collected from Pua and Tha-Wang-Pha district, studied antioxidant activity and compared the antioxidant efficacy of the extracts from the three fresh edible algae with a standard solution, 3-tert-butyl-4-hydroxyanisole （BHA）. This study found that an extract ofNostochopsis spp. was the highest antioxidant activity to DPPH free radical between 32.1 and 87.5, the highest amount of beta-carotene was 4.71-7.09 mg/g and the highest amount of phenol in fresh edible algae extracts from Microspora was between 9.37 and 37.02 mg/g. The highest vitamin C in Microspora was between 110.41-138.53 mg/100 g.展开更多
A series of coumarin-derived azolyl ethanols including imidazolyl,triazolyl,tetrazolyl,benzotriazolyl,thiol-imidazolyl and thiol-triazolyl ones were conveniently synthesized and characterized by IR,~1H NMR,^(13)C NMR ...A series of coumarin-derived azolyl ethanols including imidazolyl,triazolyl,tetrazolyl,benzotriazolyl,thiol-imidazolyl and thiol-triazolyl ones were conveniently synthesized and characterized by IR,~1H NMR,^(13)C NMR and high-resolution mass spectra(HRMS) spectra.Some of the prepared compounds showed appropriate logP_(ow) values and effective antibacterial and antifungal activities.Noticeably,compound 14 with bis-triazolyl ethanol group exhibited low minimal inhibitory concentration(MIC)value of 8 μg/mL against MRSA,which was comparable or even superior to reference drugs Norfloxacin(MIC=8μg/mL)and Chloramphenicol(MIC=16μg/mL).It could also effectively inhibit the growth of the tested fungal strains compared to Fluconazole.Further binding studies of coumarin 14 with calf thymus DNA were investigated by UV-Vis absorption and fluorescence spectroscopy.It was found that compound 14 could interact with calf thymus DNA by groove binding to form14-DNA complex via both hydrogen bonds and van der Waals force,which might be the factor to exert the powerful antimicrobial activity.展开更多
Polychlorinated biphenyls(PCBs) can antagonize human pregnane X receptor(hPXR) activation.Such chemicals could pose a serious threat to the reproductive and developmental ability of humans.The quantitative structure a...Polychlorinated biphenyls(PCBs) can antagonize human pregnane X receptor(hPXR) activation.Such chemicals could pose a serious threat to the reproductive and developmental ability of humans.The quantitative structure activity relationship(QSAR) provides a promising method for the estimation of PCBs' antagonistic activity.In this investigation,a QSAR model was developed by using heuristic method and best subset modeling(r2 = 0.873,q2LOO=0.742).The built model was validated externally by splitting the original data set into training and prediction sets.The results of the model derived are as follows:r2 = 0.907,q2LOO=0.709,r2pred=0.676,suggesting developed QSAR model had good robustness and predictive ability.The applicability domain(AD) of the model was assessed by Williams plot.The antagonistic activity(?logKi) of 108 PCBs,which are unavailable by experiment at present,was predicted within the applicability domain of the model.The critical structural features related to the activity of PCBs were identified.展开更多
A novel homoisoflavone typicalvone A （1）, together with two known compounds, n-heneicosane and p-hydroxy benzoic acid, were isolated from Aspidistra typica Baill. The structure of the new compound was elucidated by ...A novel homoisoflavone typicalvone A （1）, together with two known compounds, n-heneicosane and p-hydroxy benzoic acid, were isolated from Aspidistra typica Baill. The structure of the new compound was elucidated by sepctral techniques, viz. 1D, 2D NMR spectra and HR-ESI-MS. Compared with berberine hydrochloride, typicalvone A showed moderate anti-bacterial activities, especially against the Gram-negative Paeudomonas aeruginosa ATCC-9027 and Escherichia coli ATCC-25922, with MBC values of 1000 and 500 μg/mL, respectively. In addition, it exhibited weak inhibitory activities against the tumour cells.展开更多
文摘To study the antioxidant constituents from the stems of Dendrobium nobile, and to discuss theft structure-activity relationship. Compounds were isolated from a 60% ethanolic extract by various chromatographic techniques and were identified by spectral analysis. The antioxidant activities of compounds were evaluated by DPPH free radical scavenging assay. Five phenanthrenes and four lignans were obtained from the active fractions ofD. nobile. Their structures were identified as fimbriatone （1）, confusarin （2）, flavanthrinin （3）, 2,5-dihydroxy-4,9-dimethoxyphenanthrene （4）, 3,7-dihydroxy-2,4-dimethoxyphenanthrene （5）, syringaresinol （6）, pinoresinol （7）, medioresinol （8） and lirioresinol-A （9）, respectively. Compounds 2 and 6 exhibited more potent DPPH scavenging activities than vitamin C. All the above compounds were reported from this plant for the first time, and compounds 3, 4 and 9 were reported for the first time from the genus of Dendrobiurn. For all phenanthrenes and lignans, an electron-donating methoxyl group in the ortho position to the phenolic hydroxyl group exhibits enhanced antioxidant activities.
文摘Eleven 1-(1H-1,2,4-triazole)-2-(2,4-diflurophenyl)-3-(N-methyl-N-substituted benzylamino)-2-propanols were designed and synthesized, on the basis of the crystal structure of P450 cytochrome 14α-sterol demethylase(CYP51) and the docking results of inhibitors to the active site of the enzyme. All title compounds were first by reported. Results of preliminary biological tests showed that most of title compounds exhibited activity against the seven common pathogenic fungi. Compound 11 showed best antifungal activity with broad antifungal spectrum and proved to be more active against Cryptococcus neoformans, Candida albicans, Microsporum lanosum and Trichophyton rubrum than ketoconazole. Compounds 3, 10 and 4 also had high activities.
基金supported in part by the National Key S&T Special Projects on Major Infectious Diseases (Grant No. 2008ZX10001-002, 2008ZX10001-012)the National Natural Science Foundation of China (No. 30700706)
文摘Neutralizing antibodies are considered to be an important protective parameter used in HIV-1 vaccine evaluation. However, the exact role that neutralizing antibodies plays in controlling the disease progression of HIV-1 infected peoples is still undetermined. In this paper, we compared the protective function of the neutralizing antibody response in the plasma from LTNP and TP against clade B and clade C pseudoviruses. No difference in the neutralizing activities between the plasma from LTNP and TP was found, which was consistent with the most recent reports. In addition, no correlations between the titer or breadth and CD4+ or viral load in HIV-1 infected individuals were found. The protective roles played by neutralizing antibodies in controlling disease progression of HIV-1 infected people need to be considered in a new viewpoint.
基金Supported by National Natural Science Foundation of China (No30873400)Natural Science Foundation of Tianjin (No06YFJMC07300)
文摘Salvianolic acid B(Sal B) is an active component of traditional Chinese medicine Salvia miltiorrhiza and is used to treat vascular diseases. To better understand its mechanism, the antioxidant capacities of Sal B was evaluated with human endothelial cells under oxidative stress. Human endothelial cells were pretreated with Sal B for 12 h followed by hydrogen peroxide for another 12 h. Production of reactive oxygen species (ROS), activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX), and concentration of glu-tathione were measured. Protective effect of Sal B on the endothelial cells from hydrogen peroxide-induced damage was observed, and ROS production in the cells was found significantly inhibited. Sal B remarkably enhanced the activities of antioxidant enzymes SOD, CAT and GPX. Furthermore, Sal B up-regulated the intracellular glu-tathione concentration. The results indicate that Sal B protected endothelial cells from oxidative stress by improving the redox status of the cells through enhancing the antioxidant enzyme activities and increasing the reductive glu-tathione concentration after the oxidative challenge.
基金Supported by the Ministry of Science and Environmental Protection,Republic of Serbia(172047)
文摘The polyphenol content,antioxidant and antimicrobial activities of the extracts obtained by classical, ultrasonic and Soxhlet extractions from dry aerial parts of two Artemisia species(Artemisia vulgaris and Artemisia campestris)were compared.Ultrasound positively affected the yield of extractive substance and the kinetics of extraction,but the extract obtained by the classical extraction showed the highest antioxidant activities and contained higher total contents of phenolic compounds and flavonoids than the extracts obtained by two other extraction techniques.Both flavonoid aglycones(apigenin,quercetin,quercetin 3,3′-dimethyl ether)and flavonoid glycosides(rutin,hyperoside and kaempferol 3-rhamnoside)were identified by thin layer chromatograph(TLC)analysis in the extracts from both species.A.campestris extracts were richer in quercetin than A.vulgaris and its antimicrobial activity was also better than A.vulgaris.Extracts obtained from both species were found to be more effective on the tested yeasts than bacteria.The kinetics of the total extractive substances,such as phenolic,flavonoids and quercetin extraction,was successfully described by the model of unsteady-state diffusion.
文摘To investigate into the mechanisms underlying the irreversible sterility induced by gossypol, we studied the relationship between its inhibitory action on acrosomal enzymes and its antifertility effect.As shown by our result, after exposure to gossypol (l.25-60 μg/ml) for 15 min. in vitro,the sperms' ability to penetrate bovine cervical mucus and the fertility rate were significantly reduced. Also, following administration of gossypol (12.5 mg/kg/day) for six weeks, the rate of fertilization in vitro by hamster sperm was significantly decreased. In the gossypol-treated group, extracts of testis sperm delayed dispersion of cumulus cells, suggesting inhibition of hyaluronidase and other acrosomal enzymes. Furthermore, the acrosin and arylsulfatase activities were shown to be markedly inhibited. Thus, a parallelism was displayed between the reduction of fertility and the decreasc in acrosin and arylsulfatase activities in epididymis sperms.Besides, the inhibition was reversible and was dosage-and durationdependent. In conclusion, the assay of acrosin activity might serve as a useful tool for monitoring the irreversible sterility induced by gossypol,
文摘Functional properties of Talbina were used in ancient Arab for nutritional purpose. It was a meal made from barley flour and milk. The high antioxidant Talbina was formulated from whole flour of harley and oat, milk, date palm syrup （debis） and date palm seeds. The chemical composition, organoleptic properties and antioxidant activity of high antioxidant Talbina were determined. Sensory evaluation of traditional and high antioxidant Talbina showed that the developed product Talbina was considered as good for overall acceptability of all panelists. Also, the formulated Talbina contains high values of antioxidants components and natural nutrients. The antioxidant activity of formulated Talbina containing barley or oat may be due to presence of phenolic compounds and proanthocyanidins in the barley and oat. Increasing the antioxidant activity of high antioxidant Talbina containing barley and oat may be due to the adding of dates palm seeds which contain very high values of phenolic compounds and other antioxidants components. Date palm seeds as well as barley and/or oat give high antioxidants components which protect cells from oxidative stress and help to reduce the risk of cancer and heart disease as well as natural anti-depressant. Moreover, increasing the antioxidant activity in the formulated Talbina may play a role for reducing power, radical scavenging activity and the lipid peroxidation inhibition. In conclusion, supplementation of traditional Talbina containing barley and/or oat with date palm syrup （debis） and date palm seeds can produce simple and healthy meal to provide a good source of daily dietary antioxidants and micronutrients.
文摘Tetraphenyl-porphyrin iron （FeTPP） was chosen to sensitize Cr doped TiO2 （Cr-TiO2） nanoparticles, a novel multimodified photocatalyst FeTPP-Cr-TiO2 with excellent visible- light photocatalytic activity was successfully synthesized. The FeTPP-Cr-TiO2 microspheres were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electronic microscopy, X-ray photoelectron spectroscopy, UV-Vis diffuse reflectance spectra and N2 adsorption-desorption isotherms. The photocatalytic activity of FeTPP-Cr-TiO2 was evaluated by degradations of methylene blue in aqueous solution under irradiation with Xe lamp （150 W）. The results showed that the FeTPP-Cr-TiO2 multimodified photocatalyst was anatase phase with high specific surface area （74.7 m^2/g）, and exhibited higher photocatalytic degradation efficiency than Cr-TiO2 and FeTPP-TiO2. The photocatalytic degradations of three quinolone antibiotics （lomefioxacin, norfioxacin, and ofioxacin） were further estimated for the feasibility of practical application of catalyst in wastewater treatment. It is desirable that photodegradation of antibiotics with FeTPP-Cr-TiO2 achieved pretty high degradation rates and all followed the pseudo first-order reaction model, and the rate constants k of 3.02×10^-2, 2.81×10^-2, and 3.86×10^-2 min-1 and the half-lifes t1/2 of 22.9, 24.6, and 17.9 min were achieved respectively.
文摘Antioxidant efficiency was studied in fresh edible algae： Cladophora, Microspara and Nostochopsis spp. from Nan River, Nan province. The samples were collected from Pua and Tha-Wang-Pha district, studied antioxidant activity and compared the antioxidant efficacy of the extracts from the three fresh edible algae with a standard solution, 3-tert-butyl-4-hydroxyanisole （BHA）. This study found that an extract ofNostochopsis spp. was the highest antioxidant activity to DPPH free radical between 32.1 and 87.5, the highest amount of beta-carotene was 4.71-7.09 mg/g and the highest amount of phenol in fresh edible algae extracts from Microspora was between 9.37 and 37.02 mg/g. The highest vitamin C in Microspora was between 110.41-138.53 mg/100 g.
基金supported by the National Natural Science Foundation of China(21172181,21372186,81450110094, 81250110089,81350110338)the Key Program from Natural Science Foundation of Chongqing(CSTC2012jjB10026)the Specialized Research Fund for the Doctoral Program of Higher Education of China(SRFDP 20110182110007)
文摘A series of coumarin-derived azolyl ethanols including imidazolyl,triazolyl,tetrazolyl,benzotriazolyl,thiol-imidazolyl and thiol-triazolyl ones were conveniently synthesized and characterized by IR,~1H NMR,^(13)C NMR and high-resolution mass spectra(HRMS) spectra.Some of the prepared compounds showed appropriate logP_(ow) values and effective antibacterial and antifungal activities.Noticeably,compound 14 with bis-triazolyl ethanol group exhibited low minimal inhibitory concentration(MIC)value of 8 μg/mL against MRSA,which was comparable or even superior to reference drugs Norfloxacin(MIC=8μg/mL)and Chloramphenicol(MIC=16μg/mL).It could also effectively inhibit the growth of the tested fungal strains compared to Fluconazole.Further binding studies of coumarin 14 with calf thymus DNA were investigated by UV-Vis absorption and fluorescence spectroscopy.It was found that compound 14 could interact with calf thymus DNA by groove binding to form14-DNA complex via both hydrogen bonds and van der Waals force,which might be the factor to exert the powerful antimicrobial activity.
基金supported by the Science and Technology Development Foundation Key Project of Nanjing Medical University (09NJMUZ16)Natural Science Research Project of Institution of Higher Education of Jiangsu Province (11KJB180006)
文摘Polychlorinated biphenyls(PCBs) can antagonize human pregnane X receptor(hPXR) activation.Such chemicals could pose a serious threat to the reproductive and developmental ability of humans.The quantitative structure activity relationship(QSAR) provides a promising method for the estimation of PCBs' antagonistic activity.In this investigation,a QSAR model was developed by using heuristic method and best subset modeling(r2 = 0.873,q2LOO=0.742).The built model was validated externally by splitting the original data set into training and prediction sets.The results of the model derived are as follows:r2 = 0.907,q2LOO=0.709,r2pred=0.676,suggesting developed QSAR model had good robustness and predictive ability.The applicability domain(AD) of the model was assessed by Williams plot.The antagonistic activity(?logKi) of 108 PCBs,which are unavailable by experiment at present,was predicted within the applicability domain of the model.The critical structural features related to the activity of PCBs were identified.
基金The Project of Department of Science in Sichuan Province(Grant No.14ZA0003)
文摘A novel homoisoflavone typicalvone A （1）, together with two known compounds, n-heneicosane and p-hydroxy benzoic acid, were isolated from Aspidistra typica Baill. The structure of the new compound was elucidated by sepctral techniques, viz. 1D, 2D NMR spectra and HR-ESI-MS. Compared with berberine hydrochloride, typicalvone A showed moderate anti-bacterial activities, especially against the Gram-negative Paeudomonas aeruginosa ATCC-9027 and Escherichia coli ATCC-25922, with MBC values of 1000 and 500 μg/mL, respectively. In addition, it exhibited weak inhibitory activities against the tumour cells.
