Lead concentrations in roots, stems and leaves of accumulating and non accumulating ecotypes of Sedum alfredii (Hance) were studied through a hydroponic experiment with different Pb concentrations supplied as Pb(...Lead concentrations in roots, stems and leaves of accumulating and non accumulating ecotypes of Sedum alfredii (Hance) were studied through a hydroponic experiment with different Pb concentrations supplied as Pb(NO 3) 2. Lead concentrations in leaves and stems of the accumulating ecotype were 4-9 times and 3-5 times those of the non accumulating ecotype, and Pb accumulated amounts in stems and leaves of the accumulating ecotype were 4-9 times and 8-11 times higher than those of the non accumulating ecotype, respectively. The results indicated that the accumulating ecotype had better ability to transport Pb from roots to shoots. The subcellular distributions of Pb in the root, stem and leaf tissues were studied using sucrose differential centrifugation. Approximately 50% of Pb contents was found to be associated with the cell wall fraction in stems of the accumulating ecotype and the percentage increased to 80% both in roots and leaves, no matter when plants were grown with different levels of Pb. The results indicated that the distribution of Pb on cell walls of the accumulating ecotype could mainly account for the high tolerance to Pb.展开更多
Air pollution is harm and discomfort to human or other living organisms, it also causes damage to the environment. The aim of this project was to study the effect of air pollutions on structure and pollen grains devel...Air pollution is harm and discomfort to human or other living organisms, it also causes damage to the environment. The aim of this project was to study the effect of air pollutions on structure and pollen grains development in Chenopodium album. Anthers of Chenopodium album L. were collected at different stages of development from control （less polluted） and polluted areas （mainly SO2, NO2, CO and APM）. Structure and development of pollen grains were studied and compared. The effects of pollution on pollen structure was investigated under Light and Scanning electron microscopy and the results showed that when pollen grains were exposed to polluted air they became abnormality in form and covered with large amounts of pollutants compared to control ones. Pollen abnormalities were seen as irregularity, shrinkage, thinning and breakage of the exine. Cellular material release was induced also. The data presented suggest that prolonged exposures of plants to air pollution may cause different biological effects at the cellular tissue and organ levels.展开更多
OBJECTIVE： The increasing popularity and widespread use of traditional Chinese herbs as alterna- tive medicine have sparked an interest in understanding their biosafety, especially in decoctions that are consumed. Th...OBJECTIVE： The increasing popularity and widespread use of traditional Chinese herbs as alterna- tive medicine have sparked an interest in understanding their biosafety, especially in decoctions that are consumed. This study aimed to assess the level of microbial and heavy metal contamination in commonly consumed herbal medicine in Malay- sia and the effects of boiling on these contamination levels. METHODS： Four commonly consumed Chinese herbal medicine in Malaysia-＂Eight Treasure Herbal Tea＂, ＂Herbal Tea＂, Xiyangshen （Radix Panacis Quin- quefolii） and Dangshen （Radix Codonopsis） were evaluated in this study. Herbal medicines were pre- pared as boiled and non-boiled decoctions, and their microbial enumeration and heavy metal detection were conducted with plate assay and atom- ic absorption spectroscopy, respectively. RESULTS： Findings revealed that herbal medicines generally had 6 Iogl0cfu/mL microbial cells and that boiling had significantly reduced microbial contaminants, where no Bacillus spp., Staphylococcus spp. and Clostridium spp. were recovered. Heavy metals such as Mn, Cu, Cd, Pb, Fe and Zn were also detect- ed from all the samples, generally in low concentra- tions （〈1 mg/L） except for Mn （18.545 mg/L）. All de- coctions （after boiling） have reduced concentra- tions of Cu, while others were not significantly dif- ferent. Comparisons between samples with single and multi-herbs suggest level of microbial and metal contamination is not influenced by number of herbs in sample. CONCLUSION： Herbal medicines generally have microbial and heavy metal contaminants. However, the boiling process to generate decoctions was able to successfully reduce the number of microbes and Cu, ensuring safety of herbal medicines for consumption.展开更多
The combined use of plants and bacteria is a promising approach for the remediation of soil contaminated with organic pollutants. Different biotic and abiotie factors can affect the survival and activity of the applie...The combined use of plants and bacteria is a promising approach for the remediation of soil contaminated with organic pollutants. Different biotic and abiotie factors can affect the survival and activity of the applied bacteria and consequently plant growth and phy- toremediation efficiency. The effect of inoculum density on the abundance and expression of alkune-degrading genes in the rhizosphere of plant vegetated in hydrocarbon-contaminated soil has been rarely observed. In this study, an alkane-degrading bacterium （Pantoea sp. strain BTRH79）, at different inoculum densities （10^5 to 10^8 cells cm^-3 soil）, was inoculated to ryegrass （Lolium perenne） vegetated in diesel-contaminated soil to find the optimum inoculum density needed for its efficient colonization and hydrocarbon degradation activity. Bacterial inoculation improved plant growth and hydrocarbon degradation. Maximum plant growth and hydrocarbon degra- dation were observed with the inoculum having the highest cell density （10^8 cells cm^-3 soil）. Moreover, the inoculum with higher cell density exhibited more abundance and expression of alkane hydroxylase gene, CYP153. This study suggests that the inoculum density is one of the main factors that can affect bacterial colonization and activity during phytoremediation.展开更多
文摘Lead concentrations in roots, stems and leaves of accumulating and non accumulating ecotypes of Sedum alfredii (Hance) were studied through a hydroponic experiment with different Pb concentrations supplied as Pb(NO 3) 2. Lead concentrations in leaves and stems of the accumulating ecotype were 4-9 times and 3-5 times those of the non accumulating ecotype, and Pb accumulated amounts in stems and leaves of the accumulating ecotype were 4-9 times and 8-11 times higher than those of the non accumulating ecotype, respectively. The results indicated that the accumulating ecotype had better ability to transport Pb from roots to shoots. The subcellular distributions of Pb in the root, stem and leaf tissues were studied using sucrose differential centrifugation. Approximately 50% of Pb contents was found to be associated with the cell wall fraction in stems of the accumulating ecotype and the percentage increased to 80% both in roots and leaves, no matter when plants were grown with different levels of Pb. The results indicated that the distribution of Pb on cell walls of the accumulating ecotype could mainly account for the high tolerance to Pb.
文摘Air pollution is harm and discomfort to human or other living organisms, it also causes damage to the environment. The aim of this project was to study the effect of air pollutions on structure and pollen grains development in Chenopodium album. Anthers of Chenopodium album L. were collected at different stages of development from control （less polluted） and polluted areas （mainly SO2, NO2, CO and APM）. Structure and development of pollen grains were studied and compared. The effects of pollution on pollen structure was investigated under Light and Scanning electron microscopy and the results showed that when pollen grains were exposed to polluted air they became abnormality in form and covered with large amounts of pollutants compared to control ones. Pollen abnormalities were seen as irregularity, shrinkage, thinning and breakage of the exine. Cellular material release was induced also. The data presented suggest that prolonged exposures of plants to air pollution may cause different biological effects at the cellular tissue and organ levels.
文摘OBJECTIVE： The increasing popularity and widespread use of traditional Chinese herbs as alterna- tive medicine have sparked an interest in understanding their biosafety, especially in decoctions that are consumed. This study aimed to assess the level of microbial and heavy metal contamination in commonly consumed herbal medicine in Malay- sia and the effects of boiling on these contamination levels. METHODS： Four commonly consumed Chinese herbal medicine in Malaysia-＂Eight Treasure Herbal Tea＂, ＂Herbal Tea＂, Xiyangshen （Radix Panacis Quin- quefolii） and Dangshen （Radix Codonopsis） were evaluated in this study. Herbal medicines were pre- pared as boiled and non-boiled decoctions, and their microbial enumeration and heavy metal detection were conducted with plate assay and atom- ic absorption spectroscopy, respectively. RESULTS： Findings revealed that herbal medicines generally had 6 Iogl0cfu/mL microbial cells and that boiling had significantly reduced microbial contaminants, where no Bacillus spp., Staphylococcus spp. and Clostridium spp. were recovered. Heavy metals such as Mn, Cu, Cd, Pb, Fe and Zn were also detect- ed from all the samples, generally in low concentra- tions （〈1 mg/L） except for Mn （18.545 mg/L）. All de- coctions （after boiling） have reduced concentra- tions of Cu, while others were not significantly dif- ferent. Comparisons between samples with single and multi-herbs suggest level of microbial and metal contamination is not influenced by number of herbs in sample. CONCLUSION： Herbal medicines generally have microbial and heavy metal contaminants. However, the boiling process to generate decoctions was able to successfully reduce the number of microbes and Cu, ensuring safety of herbal medicines for consumption.
基金supported by the Higher Education Commission (HEC), Pakistan (No. 20-2011-1997)
文摘The combined use of plants and bacteria is a promising approach for the remediation of soil contaminated with organic pollutants. Different biotic and abiotie factors can affect the survival and activity of the applied bacteria and consequently plant growth and phy- toremediation efficiency. The effect of inoculum density on the abundance and expression of alkune-degrading genes in the rhizosphere of plant vegetated in hydrocarbon-contaminated soil has been rarely observed. In this study, an alkane-degrading bacterium （Pantoea sp. strain BTRH79）, at different inoculum densities （10^5 to 10^8 cells cm^-3 soil）, was inoculated to ryegrass （Lolium perenne） vegetated in diesel-contaminated soil to find the optimum inoculum density needed for its efficient colonization and hydrocarbon degradation activity. Bacterial inoculation improved plant growth and hydrocarbon degradation. Maximum plant growth and hydrocarbon degra- dation were observed with the inoculum having the highest cell density （10^8 cells cm^-3 soil）. Moreover, the inoculum with higher cell density exhibited more abundance and expression of alkane hydroxylase gene, CYP153. This study suggests that the inoculum density is one of the main factors that can affect bacterial colonization and activity during phytoremediation.
