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231.
Phytoextraction is an emerging cost-effective solution for remediation of contaminated soils which involves the removal of toxins, especially heavy metals and metalloids, by the roots of the plants with subsequent transport to aerial plant organs. The aim of the present investigation is to study the effects of EDTA and citric acid on accumulation potential of marigold (Tagetes erecta) to Zn, Cu, Pb, and Cd and also to evaluate the impacts of these chelators (EDTA and citric acid) in combination with all the four heavy metals on the growth of marigold. The plants were grown in pots and treated with Zn (7.3 mg l(-1)), Cu (7.5 mg I(-1)), Pb (3.7 mg l(-1)) and Cd (0.2 mg l(-1)) alone and in combination with different doses of EDTA i.e., 10, 20 and 30 mg l(-1). All the three doses of EDTA i.e., 10, 20 and 30 mg l(-1) significantly increased the accumulation of Zn, Cu, Pb and Cd by roots, stems and leaves as compared to control treatments. The 30 mg l(-1) concentration of citric acid showed reduced accumulation of these metals by root, stem and leaves as compared to lower doses i.e., 10 and 20 mg l(-1). Among the four heavy metals, Zn accumulated in the great amount (526.34 mg kg(-1) DW) followed by Cu (443.14 mg kg(-1) DW), Pb (393.16 mg kg(-1) DW) and Cd (333.62 mg kg(-1) DW) in leaves with 30 mg l(-1) EDTA treatment. The highest concentration of EDTA and citric acid (30 mg l(-1)) caused significant reduction in growth of marigold in terms of plant height, fresh weight of plant, total chlorophyll, carbohydrate content and protein content. Thus EDTA and citric acid efficiently increased the phytoextractability of marigold which can be used to remediate the soil contaminated with these metals.  相似文献   
232.
Duckweed (Lemna minor) a small vascular plant, grows rapidly, is sensitive to a wide variety of toxicants and is easy to culture. A method is described that measures duckweed frond growth, chlorophyll, protein and biomass content as indicator of growth inhibition. The physico-chemical analysis of anaerobically treated distillery effluent revealed high BOD (28,000 mg/l), COD (52,400 mg/l) and dark brown colour (180,000 Co. Pt.). This effluent showed high toxicity to Lemna minor after 96 h of exposure in laboratory condition. EC50 of the fronds for chlorophyll, protein and biomass was found to be 25%, however, the bacterial decolourised effluent showed reduction of BOD (87.50%), COD (84.50%) and colour (76%). Further the toxicity evaluation with Lemna minor showed toxicity reduction up to 63% for all tested parameters. The EC50 noted for chlorophyll, protein and biomass was 100% concentration of decolourised effluent.  相似文献   
233.
In an effort to test the hypoglycemic activity of Aegle marmelos and Hibiscus rosa sinensis in glucose induced hyperglycemic rats, their alcoholic leaf extracts were studied. Both the groups of animals receiving either. A. marmelos or H. rosa sinensis leaf extract for seven consecutive days, at an oral dose equivalent to 250 mg kg-1 showed significant improvements in their ability to utilize the external glucose load. Average blood glucose lowering caused by A. marmelos and H. rosa sinensis was 67% and 39% respectively, which shows that former significantly (p < 0.001) improves the glucose tolerance curve. The magnitude of this effect showed time related variation with both the plants. Efficacy of A. marmelos and H. rosa sinensis was 71% and 41% of glybenclamide, respectively. These data throw some light on the possible mechanism of hypoglycemic activity of both the plants. The mechanism of action could be speculated partly to increased utilization of glucose, either by direct stimulation of glucose uptake or via the mediation of enhanced insulin secretion.  相似文献   
234.
Fly ash is abundantly produced from thermal power plants and is considered a hazardous waste. However, in recent years, fly ash has been widely utilized in the agricultural sector as a soil modifier. It is particularly important for wasteland/mine spoil reclamation due to its ability to provide a source of plant nutrients and improve physicochemical properties of soil. Although fly ash itself contains many plant nutrients, most nutrients, including phosphorus (P), are in a bound form not easily available to plants. This study analyzed the effect of farm manure on the solubility of P from fly ash. Incubation studies were conducted to determine the effect of farm manure on P solubilization to use as a potential option for remediation. © 2007 Wiley Periodicals, Inc.  相似文献   
235.
Popularity of herbal drugs is increasing all over the world because of lesser side effects as compared to synthetic drugs. Besides, it costs less and easily available to poor people particularly in developing countries. But quality assurance of herbal drugs is very necessary prior to its use. Because in today's polluted environment, even herbal drugs are not safe. Berberis spp. is very important medicinal plant, having various medicinal properties. It is also included in Indian and British pharmacopoeias. Its demand is quite high in herbal drug market. So, to check the quality of market samples of this drug, ten different samples were procured from different drug markets of India for heavy metal estimation. Besides, genuine samples of four species of Berberis viz. B. aristata, B. chitria, B. lycium, B. asiatica were also collected from natural habitats to compare heavy metal concentration in both market and genuine samples. It was found that market samples were much more contaminated than genuine samples. Lead (Pb) concentration is far beyond from WHO permissible limit (10 ppm) for herbal drugs, reaching to maximum 49.75 ppm in Amritsar market sample. Likewise, concentration of all other metals like Cd, Cr and Ni were also very high in market samples as compared to genuine samples.  相似文献   
236.

Mitochondria play a central role in maintaining cellular and metabolic homeostasis during vital development cycles of foetal growth. Optimal mitochondrial functions are important not only to sustain adequate energy production but also for regulated epigenetic programming. However, these organelles are subtle targets of environmental exposures, and any perturbance in the defined mitochondrial machinery during the developmental stage can lead to the re-programming of the foetal epigenetic landscape. As these modifications can be transferred to subsequent generations, we herein performed a cross-sectional study to have an in-depth understanding of this intricate phenomenon. The study was conducted with two arms: whereas the first group consisted of in utero pro-oxidant exposed individuals and the second group included controls. Our results showed higher levels of oxidative mtDNA damage and associated integrated stress response among the exposed individuals. These disturbances were found to be closely related to the observed discrepancies in mitochondrial biogenesis. The exposed group showed mtDNA hypermethylation and changes in allied mitochondrial functioning. Altered expression of mitomiRs and their respective target genes in the exposed group indicated the possibilities of a disturbed mitochondrial-nuclear cross talk. This was further confirmed by the modified activity of the mitochondrial stress regulators and pro-inflammatory mediators among the exposed group. Importantly, the disturbed DNMT functioning, hypermethylation of nuclear DNA, and higher degree of post-translational histone modifications established the existence of aberrant epigenetic modifications in the exposed individuals. Overall, our results demonstrate the first molecular insights of in utero pro-oxidant exposure associated changes in the mitochondrial-epigenetic axis. Although, our study might not cement an exposure-response relationship for any particular environmental pro-oxidant, but suffice to establish a dogma of mito-epigenetic reprogramming at intrauterine milieu with chronic illness, a hitherto unreported interaction.

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237.
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