排序方式： 共有4条查询结果，搜索用时 15 毫秒
1
1.
采用室内暴露试验方法,以单细胞凝胶电泳技术(SCGE)检测,研究了Cu、Pb不同浓度梯度与不同暴露时间联合染毒对泥鳅卵细胞DNA的损伤.结果表明,各Cu、Pb浓度组DNA平均迁移长度增加,与阴性对照组比较差异有显著性(P＜0.05).此外,随着Cu、Pb染毒剂量的增加,各试验组DNA的平均迁移长度逐渐增加,在试验浓度梯度范围内(Cu 0.01mg/L+Pb 0.05mg/L、Cu 0.10mg/L+Pb 0.50mg/L、Cu 0.25mg/L+Pb 0.75mg/L),存在较为显著的剂量-效应关系(P＜0.05),但未见明显的时间-效应关系(P＞0.05).Cu、Pb可引起泥鳅卵细胞凋亡和DNA损伤,卵细胞的不同损伤水平可望作为较为理想的水环境基因毒性指标. 相似文献
2.
V. A. Vavilin 《Water Resources》2010,37(3):399-410
Degradation mechanism of diethylhexylphthalate, a pollutant of water bodies, is analyzed. A modified first-order equation
with a correction for a nondegradable fraction is suggested. The succession of biochemical reactions in the process of anaerobic
degradation of monoethylhexylphthalate is considered, and two stages—ester hydrolysis and phthalic acid transformation into
methane and carbon dioxide—are identified as limiting the overall rate. A one-dimensional distributed model is used to describe
the degradation of three phthalates with different water solubility: diethylphthalate DEP, which has a relatively high solubility;
dibutyl phthalate DBP, poorly soluble; and diethylhexylphthalate DEHP, almost insoluble. The physicochemical processes of
sorption/desorption play an important role in the process of their degradation. The enzymatic splitting, carried out by microorganisms,
reduces the concentration of dissolved diethylhexylphthalate and can facilitate desorption processes. 相似文献
3.
A potassium solubilizing bacterial strain designated EGT, which is tolerant of high temperature, was isolated from an earthworm’s gut to obtain a bacterium that can weather potassium-bearing rock effectively through solid-state fermentation. Molecular phylogeny and 16S rRNA gene sequence analysis demonstrated the bacterial strain was a member of the Streptomyces genus. To assess its potential to release potassium from silicate minerals, this strain was used to degrade potassium-bearing rock powder by solid-state fermentation. After fermentation, the amount of water-soluble Al, Fe and K of the substrate with active inoculum was higher than those of the control, which had autoclaved inoculum, and those of the fresh substrate. The result indicated that the strain had the ability to weather potassium-bearing rock and could be used as an inoculum in the production of potassium bio-fertilizer, due to its potassium release activity from rock and tolerance to high temperature. 相似文献
4.
GUPTA Pratibh BALAJI Raju PARANI M CHANDRA T S SHUKLA P KUMAR Anil BANDOPADHYAY Rajib 《海洋学报(英文版)》2015,34(8):73-82
Fifty-seven bacteria were isolated from Southern Ocean(Indian sector) water samples which were collected from different latitude and longitude of the ocean. All the isolates were able to grow at 4°C, 20°C, 37°C and tolerable Na Cl concentration up to 13.5%(w/v). 29 out of 57 isolates were identified using 16 S rDNA amplification and the sequences were submitted to National Center for Biotechnology Information(NCBI). All the isolates were classified by using Ribosomal Database Project(RDP) and found that isolates belongs to Proteobacteria and Bacteriodes. The average G+C content was 56.4%. The isolates were screened for the presence of extracellular enzymes, viz. amylase, catalase, urease, esterase, lipase and protease. The disc diffusion method is used to screen antibiotic production by the isolates against four pathogenic bacteria, viz. Salmonella typhimurium(NCIM 2501),Staphylococcus aureus(NCIM 2122), Bacillus subtilis(NCIM 2193), and Pseudomonas aeruginosa(NCIM 2036).Nine out of 29 were found to be antibiotic producer. 相似文献
1