Diatoms are widely distributed in many temperate areas and some species frequently form extensive blooms in spring. Hence, monitoring the variations of specific genera or species of diatoms is necessary for studying p...Diatoms are widely distributed in many temperate areas and some species frequently form extensive blooms in spring. Hence, monitoring the variations of specific genera or species of diatoms is necessary for studying phytoplankton population dynamics in marine ecosystems. To test whether pigment ratios can be used to identify diatoms at a below-class taxonomic level, we analyzed 14 species/strains of diatoms isolated from Chinese seas using high performance liquid chromatography （HPLC）. We normalized all pigment concentrations to total chlorophyll a to calculate the ratios of pigment to chlorophyll a, and calculated the ratios between accessory pigments （or pigment sums）. Cluster analysis indicated that these diatoms could be classified into four clusters in terms of three accessory pigment ratios： chlorophyll c2： chlorophyll Cl, fucoxanthin：total chlorophyll c and diadinoxanthin：diatoxanthin. The classification results matched well with those of biological taxonomy. To test the stability of the classification, pigment data from one species, cultured under different light intensities, and five new species/strains were calculated and used for discriminant analysis. The results show that the classification of diatom species using pigment ratio suites was stable for the variations of pigment ratios of species cultured in different light intensities. The introduction of new species, however, may confuse the classification within the current scheme. Classification of marine diatoms using pigment ratio suites is potentially valuable for the fine chemotaxonomy of phytoplankton at taxonomic levels below class and would advance studies on phytoplankton population dynamics and marine ecology.展开更多
Fucoxanthin content of five brown seaweed species of East Java collected from Talango district （Madura sea-Jawa sea） namely Padina australis, Turbinaria conoides, Sargassum cinereum, Sargassum filipendula and Sargas...Fucoxanthin content of five brown seaweed species of East Java collected from Talango district （Madura sea-Jawa sea） namely Padina australis, Turbinaria conoides, Sargassum cinereum, Sargassum filipendula and Sargassum echinocarpum were determined and samples were collected using Global Positioning System （GPS）. Fucoxanthin from those samples was determined using Thin Layer Chromatography （TLC）, High Pressure Liquid Chromatography （HPLC） and Spectrophotometer UV-Vis and the results were then calculated using Seely equation. The pigments separation using HPLC gave a better result compared to TLC, and beside fucoxanthin otlher pigments namely chlorophyll and β carotene were also identified in these samples. Four points of sampling location were chosen using GPS and spot with coordinate positions observed were 113.94444° EL-7.08795° SA; 113.94231° EL-7.08913° SA. The results showed that fucoxanthin content were as follow： Padina australis 0.2674± 0.0046 mg/g; Turbinaria conoides 0.2134± 0.0100 mg/g; Sargassum filipendula 0.1957 ± 0.0173 mg/g; Sargassum cinereum 0.1640 ± 0.0092 mg/g and Sargassum echinocarpum 0.1576 ± 0.0001 mg/g. It can be concluded that Padina australis and Turbinaria conoides contain the most amount of fucoxanthin and it is possible to be cultivated as edible brown seaweed fucoxanthin resources.展开更多
The study examined the photodegradative efficiency of ZnO and TiO2 in degradation of antibiotics in aqueous matrices. Among several types of antibiotics, four antibiotics were chosen to feature the major classes of th...The study examined the photodegradative efficiency of ZnO and TiO2 in degradation of antibiotics in aqueous matrices. Among several types of antibiotics, four antibiotics were chosen to feature the major classes of these compounds： amoxicillin, erythromycin, streptomycin and ciprofloxacin. Degradation of antibiotic solutions was carried out mainly under UV-light irradiation in a set time with the presence of small quantity of zinc oxide or titanium dioxide. Solutions were analyzed with HPLC chromatography and degradation percentages were calculated from ratio between pick area associated to no degraded drug solution and degraded drug solution＇s pick area. Meanwhile, toxicity of antibiotics and degrading compounds were investigated using a biosensor system, consisting of Clark＇s electrode associated with a portion of agar medium culture containing Saccharomyces Cerevisiae yeast cells. This way, it was possible to define the oxygen that was consumed by yeast cells. Toxicity associated to antibiotics and degrading products are related to decrease of oxygen concentration in solution. It is clear that zinc oxide is slower than titanium dioxide to degrade antibiotics, but zinc oxide shows better photodegradation efficiency than titanium dioxide in spite of its small specific superficial area.展开更多
In order to develop a model for screening the agonists of human β2-adrenoceptor from Chinese medicinal herbs extracts, we used a cell-based functional assay based on a common G protein-coupled receptor （GPCR） regul...In order to develop a model for screening the agonists of human β2-adrenoceptor from Chinese medicinal herbs extracts, we used a cell-based functional assay based on a common G protein-coupled receptor （GPCR） regulation mechanism and destabilized enhanced green fluorescent protein （d2EGFP） reporter gene technique. The positive cell clone was confirmed by real-time polymerase chain reaction （PCR） and imaging analysis. To assess the value of this model, we screened over 2000 high performance liquid chromatography （HPLC）-fractionated samples from the ethanol extracts of Chinese medicinal herbs. Six fractions （isolated from Panax japonicus, Veratrum nigrum, Phellodendron amurense, Fructus Aurantii lmmaturus, Chaenomeles speciosa, and Dictamnus dasycarpus） showed significant effects on active reporter gene expression, three of which （isolated from Phellodendron amurense, Fructus Aurantii lmmaturus, and Chaenomeles speciosa） were selected for further concentration response analysis and the half maximal effective concentration （EC1/2 max） values were 4.2, 2.7, and 4.8 μg/ml, respectively. Therefore, this reporter gene assay was suitable for screening β2-adrenoceptor agonists. The results suggest that the six herbal extracts are the possible agonists of β2-adrenoceptor.展开更多
基金Supported by the National Natural Science Foundation of China (Nos. 40806029, 40676068)the National High Technology Research and Development Program of China (863 Program) (No. 2006AA09Z178)
文摘Diatoms are widely distributed in many temperate areas and some species frequently form extensive blooms in spring. Hence, monitoring the variations of specific genera or species of diatoms is necessary for studying phytoplankton population dynamics in marine ecosystems. To test whether pigment ratios can be used to identify diatoms at a below-class taxonomic level, we analyzed 14 species/strains of diatoms isolated from Chinese seas using high performance liquid chromatography （HPLC）. We normalized all pigment concentrations to total chlorophyll a to calculate the ratios of pigment to chlorophyll a, and calculated the ratios between accessory pigments （or pigment sums）. Cluster analysis indicated that these diatoms could be classified into four clusters in terms of three accessory pigment ratios： chlorophyll c2： chlorophyll Cl, fucoxanthin：total chlorophyll c and diadinoxanthin：diatoxanthin. The classification results matched well with those of biological taxonomy. To test the stability of the classification, pigment data from one species, cultured under different light intensities, and five new species/strains were calculated and used for discriminant analysis. The results show that the classification of diatom species using pigment ratio suites was stable for the variations of pigment ratios of species cultured in different light intensities. The introduction of new species, however, may confuse the classification within the current scheme. Classification of marine diatoms using pigment ratio suites is potentially valuable for the fine chemotaxonomy of phytoplankton at taxonomic levels below class and would advance studies on phytoplankton population dynamics and marine ecology.
文摘Fucoxanthin content of five brown seaweed species of East Java collected from Talango district （Madura sea-Jawa sea） namely Padina australis, Turbinaria conoides, Sargassum cinereum, Sargassum filipendula and Sargassum echinocarpum were determined and samples were collected using Global Positioning System （GPS）. Fucoxanthin from those samples was determined using Thin Layer Chromatography （TLC）, High Pressure Liquid Chromatography （HPLC） and Spectrophotometer UV-Vis and the results were then calculated using Seely equation. The pigments separation using HPLC gave a better result compared to TLC, and beside fucoxanthin otlher pigments namely chlorophyll and β carotene were also identified in these samples. Four points of sampling location were chosen using GPS and spot with coordinate positions observed were 113.94444° EL-7.08795° SA; 113.94231° EL-7.08913° SA. The results showed that fucoxanthin content were as follow： Padina australis 0.2674± 0.0046 mg/g; Turbinaria conoides 0.2134± 0.0100 mg/g; Sargassum filipendula 0.1957 ± 0.0173 mg/g; Sargassum cinereum 0.1640 ± 0.0092 mg/g and Sargassum echinocarpum 0.1576 ± 0.0001 mg/g. It can be concluded that Padina australis and Turbinaria conoides contain the most amount of fucoxanthin and it is possible to be cultivated as edible brown seaweed fucoxanthin resources.
文摘The study examined the photodegradative efficiency of ZnO and TiO2 in degradation of antibiotics in aqueous matrices. Among several types of antibiotics, four antibiotics were chosen to feature the major classes of these compounds： amoxicillin, erythromycin, streptomycin and ciprofloxacin. Degradation of antibiotic solutions was carried out mainly under UV-light irradiation in a set time with the presence of small quantity of zinc oxide or titanium dioxide. Solutions were analyzed with HPLC chromatography and degradation percentages were calculated from ratio between pick area associated to no degraded drug solution and degraded drug solution＇s pick area. Meanwhile, toxicity of antibiotics and degrading compounds were investigated using a biosensor system, consisting of Clark＇s electrode associated with a portion of agar medium culture containing Saccharomyces Cerevisiae yeast cells. This way, it was possible to define the oxygen that was consumed by yeast cells. Toxicity associated to antibiotics and degrading products are related to decrease of oxygen concentration in solution. It is clear that zinc oxide is slower than titanium dioxide to degrade antibiotics, but zinc oxide shows better photodegradation efficiency than titanium dioxide in spite of its small specific superficial area.
基金Project (No. 30873103) supported by the National Natural Science Foundation of China
文摘In order to develop a model for screening the agonists of human β2-adrenoceptor from Chinese medicinal herbs extracts, we used a cell-based functional assay based on a common G protein-coupled receptor （GPCR） regulation mechanism and destabilized enhanced green fluorescent protein （d2EGFP） reporter gene technique. The positive cell clone was confirmed by real-time polymerase chain reaction （PCR） and imaging analysis. To assess the value of this model, we screened over 2000 high performance liquid chromatography （HPLC）-fractionated samples from the ethanol extracts of Chinese medicinal herbs. Six fractions （isolated from Panax japonicus, Veratrum nigrum, Phellodendron amurense, Fructus Aurantii lmmaturus, Chaenomeles speciosa, and Dictamnus dasycarpus） showed significant effects on active reporter gene expression, three of which （isolated from Phellodendron amurense, Fructus Aurantii lmmaturus, and Chaenomeles speciosa） were selected for further concentration response analysis and the half maximal effective concentration （EC1/2 max） values were 4.2, 2.7, and 4.8 μg/ml, respectively. Therefore, this reporter gene assay was suitable for screening β2-adrenoceptor agonists. The results suggest that the six herbal extracts are the possible agonists of β2-adrenoceptor.
