Under conditions of increased pollution of water resources,the search for effective and environmentally safe methods of wastewater treatment becomes an urgent task.As noted by many researchers Lemna minor L.and Azolla...Under conditions of increased pollution of water resources,the search for effective and environmentally safe methods of wastewater treatment becomes an urgent task.As noted by many researchers Lemna minor L.and Azolla caroliniana have great potential for biological treatment of wastewater.The present study is devoted to the biological treatment of municipal wastewater of Osh city(Kyrgyzstan)using aquatic plants Lemna minor L.and Azolla caroliniana Willd.Experiments were conducted in concrete basins of treatment facilities.The area of each pool was 1 m^(2),depth 30–45 cm.The temperature of nutrient media ranged from 20 to 35℃,pH from 6.1 to 8.7,and light intensity from 284 to 360 W/m^(2)FAR.The results showed that the cultivation of Lemna minor resulted in the oxygenation of wastewater and,a significant reduction of pollutants and pathogens.At the same time,the use of Azolla caroliniana provided a significant improvement in the physicochemical characteristics of water-reduction of BOD_(5)to 4.3 mgO_(2)/L,disappearance of all forms of nitrogen,as well as improvement of transparency and elimination of unpleasant odor.Thus,both plants showed high potential as biological treatment agents.The obtained data confirm the prospect of their application for a sustainable water treatment system in the conditions of southern regions of Kyrgyzstan.展开更多
Reactive oxygen species (ROS) scavengers, including ascorbate peroxidase, superoxide dismutase, catalase and peroxidase, are the most commonly used biomarkers in assessing an organisms' response to many biotic and ...Reactive oxygen species (ROS) scavengers, including ascorbate peroxidase, superoxide dismutase, catalase and peroxidase, are the most commonly used biomarkers in assessing an organisms' response to many biotic and abiotic stresses. In this study, we cloned an 866 bp GST(phi) gene in Lemna minor and investigated its characteristics, expression and enzymatic activities under 75 lamol/L cadmium concentrations in comparison with other ROS scavengers. GST(phi) gene expression patterns were similar to those of other scavengers of ROS. This suggests that GST(phi) might be involved in responding to heavy metal (cadmium) stress and that its expression level could be used as a bio-indicator in monitoring cadmium pollution.展开更多
Since the finding of CaM, i. e. Ca<sup>2+</sup>-receptor in animals and plants, the roles of Ca<sup>2+</sup> and CaM acting as the second messengers have been widely studied. In animals, CaM ca...Since the finding of CaM, i. e. Ca<sup>2+</sup>-receptor in animals and plants, the roles of Ca<sup>2+</sup> and CaM acting as the second messengers have been widely studied. In animals, CaM can regulate much more enzymes and cell functions than cAMP, it can even regulate cAMP,展开更多
Ⅰ. INTRODUCTIONZearalenone was found by Stob et al. in 1962 as a secondary metabolite produced by Gibberella zeae. It was reported that zearalenone not only acts as an estrogenic substance but also as a sexual hormon...Ⅰ. INTRODUCTIONZearalenone was found by Stob et al. in 1962 as a secondary metabolite produced by Gibberella zeae. It was reported that zearalenone not only acts as an estrogenic substance but also as a sexual hormone in certain fungi. Since 1980, zearalenone has been isolated, purified and identified from higher plants in different genera and species by Meng et al. and is proposed as an endogenous active substance closely related to sexual differentiation展开更多
文摘Under conditions of increased pollution of water resources,the search for effective and environmentally safe methods of wastewater treatment becomes an urgent task.As noted by many researchers Lemna minor L.and Azolla caroliniana have great potential for biological treatment of wastewater.The present study is devoted to the biological treatment of municipal wastewater of Osh city(Kyrgyzstan)using aquatic plants Lemna minor L.and Azolla caroliniana Willd.Experiments were conducted in concrete basins of treatment facilities.The area of each pool was 1 m^(2),depth 30–45 cm.The temperature of nutrient media ranged from 20 to 35℃,pH from 6.1 to 8.7,and light intensity from 284 to 360 W/m^(2)FAR.The results showed that the cultivation of Lemna minor resulted in the oxygenation of wastewater and,a significant reduction of pollutants and pathogens.At the same time,the use of Azolla caroliniana provided a significant improvement in the physicochemical characteristics of water-reduction of BOD_(5)to 4.3 mgO_(2)/L,disappearance of all forms of nitrogen,as well as improvement of transparency and elimination of unpleasant odor.Thus,both plants showed high potential as biological treatment agents.The obtained data confirm the prospect of their application for a sustainable water treatment system in the conditions of southern regions of Kyrgyzstan.
基金Supported by the National Natural Science Foundation of China(No.31370296)the Shandong Provincial Natural Science Foundation of China(Nos.Y2007D34,ZR2011CM044)the Key Technologies R&D Program of Shandong Province of China(No.2010GNC10937)
文摘Reactive oxygen species (ROS) scavengers, including ascorbate peroxidase, superoxide dismutase, catalase and peroxidase, are the most commonly used biomarkers in assessing an organisms' response to many biotic and abiotic stresses. In this study, we cloned an 866 bp GST(phi) gene in Lemna minor and investigated its characteristics, expression and enzymatic activities under 75 lamol/L cadmium concentrations in comparison with other ROS scavengers. GST(phi) gene expression patterns were similar to those of other scavengers of ROS. This suggests that GST(phi) might be involved in responding to heavy metal (cadmium) stress and that its expression level could be used as a bio-indicator in monitoring cadmium pollution.
基金Project supported by the Foundation of Gansu Natural Science
文摘Since the finding of CaM, i. e. Ca<sup>2+</sup>-receptor in animals and plants, the roles of Ca<sup>2+</sup> and CaM acting as the second messengers have been widely studied. In animals, CaM can regulate much more enzymes and cell functions than cAMP, it can even regulate cAMP,
基金Project supported by the National Natural Science Foundation of China.
文摘Ⅰ. INTRODUCTIONZearalenone was found by Stob et al. in 1962 as a secondary metabolite produced by Gibberella zeae. It was reported that zearalenone not only acts as an estrogenic substance but also as a sexual hormone in certain fungi. Since 1980, zearalenone has been isolated, purified and identified from higher plants in different genera and species by Meng et al. and is proposed as an endogenous active substance closely related to sexual differentiation
文摘PDS基因编码控制类胡萝卜素生物合成过程中的关键酶,其被沉默或抑制性表达会使叶片组织出现斑驳、黄化、白化的现象.构建绿萍(Lemna minor)LmPDS基因RNAi载体及完成遗传转化研究,对于实现RNAi技术在绿萍中的应用具有重要意义.选取595 bp LmPDS基因片段为干涉片段,利用中间载体pUCCRNAi将克隆的LmPDS干涉片段正反向插入植物表达载体pCAMBIA2300-35S-OCST中.将成功构建的RNAi载体通过农杆菌介导法转入绿萍愈伤,经愈伤抗性筛选、植株再生、植株扩培、标记基因NPTII检测等过程,获得植株70株,其中4株为转基因阳性植株.再经荧光定量PCR分析、番茄红素含量检测、表型观察转基因植株.结果显示,转基因阳性植株LmPDS相对表达量明显下降,为对照的28.8%-40.5%,其番茄红素含量也明显下降,且叶片出现了明显的白化表型.本研究成功构建绿萍LmPDS基因RNAi载体,实现了RNAi在绿萍中的应用,结果可为进一步的绿萍基因功能研究提供材料和方法.(图11表1参30)