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401.
The anti-seasonal hydrology with 30 m water fluctuations in the Three Gorges Reservoir(TGR) of China attracts growing environmental and ecological concerns. We investigated the biotransformation of the herbicide propanil in plants dominating in the littoral zone of the TGR by applying the ~(14)C-ring-labeled herbicide into non-aseptic hydroponic plant systems(Cynodon dactylon, Nelumbo nucifera and Bidens pilosa), aseptic plants(Lemna minor and Lemna gibba) and cell suspension cultures(C. dactylon and L. minor).(1) Propanil absorbed in plants of the hydroponic systems was(12.46 ± 1.63)% of applied radioactivity(AR)(C. dactylon),(52.36 ± 6.38)%(N. nucifera) and(76.55 ± 6.07)%(B. pilosa), respectively. The ~(14)C-residues in the plant extractable fractions and the corresponding media were confirmed by radio-Thin Layer Chromatography(TLC), radio-High Performance Liquid Chromatography(HPLC) and Gas Chromatography-Electron Ionization Mass Spectrometry(GC–EIMS) as propanil,3,4-dichloroaniline(DCA) and N-(3,4-dichlorophenyl)-β-D-glucopyranosylamine(Glu-DCA).(2)About 8% of AR was taken up by both aseptic plants, from which 7.0% of AR was extracted and identified also as propanil, DCA and Glu-DCA.(3) Concerning cell suspension cultures,(39.22 ±9.39)% of AR was absorbed by C. dactylon after 72 hr, whereas the accumulated ~(14)C-propanil by L.minor cell suspension culture amounted to(65.04 ± 1.72)% after 7 days. The identified compounds in cell cultures are consistent with those in the tested plants. Most of the pesticide residues in the intact plants were un-extractable, which are recognized as the end of the detoxification process. We therefore consider these plants as suitable for the phytoremediation of the herbicide propanil in the TGR region. 相似文献
402.
Plant origin of Okinawan propolis: honeybee behavior observation and phytochemical analysis 总被引:1,自引:0,他引:1
Kumazawa S Nakamura J Murase M Miyagawa M Ahn MR Fukumoto S 《Die Naturwissenschaften》2008,95(8):781-786
Propolis is a natural resinous product collected by honeybees from certain plants. It has gained popularity as a food and
alternative medicine. Poplar and Baccharis are well known as the source plants of European and Brazilian propolis, respectively. However, the propolis from Okinawa,
Japan, contains some prenylflavonoids not seen in other regions such as Europe and Brazil, suggesting that the plant origin
of Okinawan propolis is a particular plant that grows in Okinawa. To identify the plant origin of Okinawan propolis, we observed
the behavior of honeybees as they collected material from plants and caulked it inside the hive. Honeybees scraped resinous
material from the surface of plant fruits of Macaranga tanarius and brought it back to their hive to use it as propolis. We collected samples of the plant and propolis, and compared their
constituents by high-performance liquid chromatography with a photo-diode array detector. We also compared their 1,1-diphenyl-2-picryl-hydrazyl
radical scavenging activity. The chemical constituents and biological activity of the ethanol extracts of the plant did not
differ from those of propolis. This indicates directly that the plant origin of Okinawan propolis is M. tanarius.
S. K. and J. N. contributed equally to this work. 相似文献
403.
Overexploitation is the second biggest driver of global plant extinction. Meanwhile, useful plant species are vital to livelihoods across the world, with global conservation efforts increasingly applying the concept of ‘conservation-through-use.’ However, successfully balancing conservation and biodiversity use remains challenging. We reviewed literature on the sustainability of wild-collected plant use across the countries of Colombia, Ecuador, Peru, and Bolivia—a region of global importance for its biological and cultural richness. After applying defined search terms and a two-stage screening process, 68 articles were reviewed. The numbers which reported sustainable, unsustainable, or context-dependent outcomes were relatively even, but national differences emerged. Through narrative synthesis, we identified five key, reoccurring themes: plant biology; land tenure; knowledge, resource, and capacity; economics and market pressures; and institutional structures, policy, and legislation. Our results show the need for flexible, context-specific approaches and the importance of collaboration, with bottom-up management and conservation methods involving local communities and traditional ecological knowledge often proving most effective. Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01529-7. 相似文献
404.
405.
A hydroponic experiment was conducted to investigate the debrominated, hydroxylated and methoxylated metabolism of polybrominated diphenyl ethers (PBDEs, BDE-15, -28 and -47) in maize. A total of six debrominated metabolites (de-PBDEs), seven hydroxylated PBDEs (OH-PBDEs, including two unidentified OH-di-PBDEs and one unidentified OH-tri-PBDE) and four methoxylated PBDEs (MeO-PBDEs) were determined in the exposed plants. The metabolic products were detected in maize only after 12 h of exposure to the PBDEs. However, the concentration of each type of the metabolites (de-PBDEs, OH-PBDEs or MeO-PBDEs) decreased at the later exposure time, possibly due to further metabolism. The removal of a bromine atom or the introduction of a hydroxyl/methoxy group was easier at the ortho-positions on the biphenyl structure than at the para-positions. Concentration ratios of the total debrominated, hydroxylated or methoxylated metabolites to the parent congener (BDE-28 or -47) generally followed the order of leaves > stems ? roots, and MeO-PBDEs > de-PBDEs ? OH-PBDEs. These results suggest that metabolism occurred preferentially in leaves and stems than in roots. Less transformation and shorter elimination half-life of OH-PBDEs would contribute to the lower concentrations of OH-PBDEs than of de-PBDEs or MeO-PBDEs in maize. 相似文献
406.
Plant uptake and dissipation of PBDEs in the soils of electronic waste recycling sites 总被引:4,自引:0,他引:4
Honglin HuangShuzhen Zhang Peter Christie 《Environmental pollution (Barking, Essex : 1987)》2011,159(1):238-243
Plant uptake and dissipation of weathered PBDEs in the soils of e-waste recycling sites were investigated in a greenhouse study. Eighteen PBDE congeners (tri- through deca-) were detected in the plant tissues. The proportion of lower brominated PBDEs (mono- through hexa-) in plant roots was higher than that in the soils. A concentration gradient was observed of PBDEs in plants with the highest concentrations in the roots followed by the stems and lowest in the leaves. Reduction rates of the total PBDEs in the soils ranged from 13.3 to 21.7% after plant harvest and lower brominated PBDEs were associated with a higher tendency to dissipate than the higher brominated PBDEs. This study provides the first evidence for plant uptake of weathered PBDEs in the soils of e-waste recycling sites and planting contributes to the removal of PBDEs in e-waste contaminated soils. 相似文献
407.
408.
409.
株洲市区农业土壤中多环芳烃的分布特征研究 总被引:3,自引:1,他引:2
采集株洲市区农业土壤表层样品185个,用高效液相色谱法对16种多环芳烃(PAHs)进行检测结果表明,除萘外,其余15种PAHs均有不同程度的检出,以苯并[b]萤蒽、萤蒽和苯并菲等3或4环PAHs为主, ~5521μg/kg之间,平均280μg/kg.地域上,石峰区、芦淞区>天元区>荷塘区;从土地利用类型看,旱地>水田>林地.按Maliszewska-Kordybach土壤污染程度分级标准,株洲市区农业土壤总体上受到PAHs轻度污染,这些PAHs主要来源于工业生产、交通运输等过程中化石燃料的燃烧. 相似文献
410.
快速溶剂萃取-气相色谱/串联质谱法测定农作物中的有机氯农药 总被引:3,自引:0,他引:3
建立快速溶剂萃取,固相萃取柱净化,气相色谱/串联四极杆质谱检测分析农作物中23种有机氯农药残留的方法。以油菜为样品,加标浓度为5、10、25、50μg/kg时,平均回收率在72%~101%之间,相对标准偏差3%~14%(n=5)。8种农作物(莴笋、黄瓜、蒜苗、辣椒、油菜、茄子、玉米和水稻)加标浓度为25μg/kg时的平均回收率在71%~113%之间,相对标准偏差3%~16%(n=5)。方法检出限0.75~1.76μg/kg之间。 相似文献