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1.
Nonpoint source pollution is the leading remaining cause of water quality problems. The extent of NPS pollution is often more difficult or expensive to monitor at the point(s) of origin, as compared to monitoring of point sources. This study evaluated the hypothesis that animal manure (chicken, cow, horse, and pig) applied to pasture contribute fecal sterols and bile acids to runoff. The study also assessed the potential benefit of fecal sterols and bile acids as biomarkers in distinguishing fecal pollution and its sources. Fecal sterol and bile acid concentrations were determined in flow-weighted composite runoff samples collected from 2.4?×?6.1 m plots (n?=?3) amended with manure. Runoff was generated from simulated rainfall (152 mm.h?1). Runoff samples from manure-amended plots showed high concentrations of fecal sterol (ranged from 13?±?1 to 1,287?±?183) and bile acid (ranged from 24?±?1 to 2,251?±?248) biomarkers. The profiles of fecal sterols and bile acids in runoff samples were similar to those of fresh manure for all selected animals. For runoff and fresh manure, chenodeoxycholic acid, deoxycholic acid, epicoprostanol, and hyodeoxycholic acid were consistent biomarkers for chicken, cow, horse, and pig, respectively, suggesting that sterols and bile acids can be used to identify sources and occurrence of fecal matter in water and sediments.  相似文献   

2.
This study assessed the efficiency of sewage treatment plants (STPs) in removing sterols based on chemical analyses of both influents and effluents. Samples from 3s and three tertiary plants were collected and analyzed by gas chromatography mass spectrometry for 23 individual sterols including mestranol, norethindrone, equol, estrone, equilin, norgestrel, 17α-ethinylestradiol, 17α-estradiol, 17β-estradiol, estriol, dihydrocholesterol (cholestanol), coprostanol, epicoprostanol, cholesterol, desmosterol, campesterol, stigmasterol, β-sitosterol, coprostanone, cholestanone, epicholestanol, stigmastanol, and 24-ethylcoprostanol. The percentage of sterols remaining in effluent samples (compared to influent samples) ranged from 0% to 80% and varied among sterol compounds and with STP location and treatment type. Differences in the efficiency of sterol removal for secondary and tertiary STPs were statistically significant. Although the concentration of sterol compounds differed between influents and effluents, sterol abundances remained the same. The most abundant sterol detected was cholesterol, followed by the fecal sterol coprostanol, and the plant sterols 24-ethylcoprostanol and β-sitosterol. For three STPs, the hormone estrone was detected in effluents at concentrations of 0.03–0.05 μg L−1. Ten sterol ratios specific for human fecal contamination and eight sterol ratios for differentiating among multiple sources of fecal contamination were calculated and showed that 12 ratios for influent and nine ratios for effluent were successful for human fecal source tracking. Based on sterol ratio values in this study, new criteria for identification of human fecal contamination were suggested.  相似文献   

3.
This study investigated the possibility of fingerprinting different organic wastes (cow, pig and horse manure) and the vermicomposts produced by different earthworm species (Eisenia andrei, Eudrilus eugeniae and Lumbricus rubellus) analyzing the profiles of fatty acid methyl esters (FAMEs). We found clear differences between their microbial communities, demonstrating the power and sensitivity of the total FAME analysis. In addition, qualitative and quantitative analyses of specific biomarkers permitted to determine differences between samples and to evaluate the effect of earthworms in the decomposition of organic matter. Fatty acid profiles were largely determined by the different vermicomposting earthworm species. Fatty acid 18:2ω6 increased significantly in horse manure vermicomposted by L. rubellus and in cow manure vermicomposted by the three earthworm species, whereas it decreased significantly in pig manure vermicomposted by L. rubellus and E. eugeniae. Fatty acid 20:4ω6 increased significantly in all vermicomposts obtained with the three earthworm species.  相似文献   

4.
The growth and reproduction of Eudrilus eugeniae were evaluated in four animal species wastes under laboratory conditions. Two hatchlings were introduced in 100 g of each animal waste i.e. cow, sheep, pig, and chicken after 15 days of pre-composting. Biomass gain, mortality, sexual maturity, and cocoons production were monitored periodically for 21 weeks. No mortality was observed in any waste. The maximum weight gain per worm and the highest growth rate per worm per week were obtained in chicken waste. Net biomass gain per worm were 1.01 ± 0.52 g, 1.318 ± 0.07 g, 0.87 ± 0.1 g, and 1.69 ± 0.15 g respectively for cow, sheep, pig, and chicken wastes. The highest number of cocoons produced per worm per day was obtained in chicken waste followed in decreasing order by sheep, cow, and pig waste. The mean number of cocoons produced per worm per day in chicken waste was 40.87% greater than these produced per day in pig waste.Among the four animal species, chicken, sheep, and cow were the most favourable wastes for the growth and reproduction of E. eugeniae, and hence can be recommended as feed materials in large scale vermicomposting facilities.  相似文献   

5.
The rapid rise in obesity-related diseases has increased interest in oral and dietary agents that disrupt fat metabolism, resulting in the excretion of dietary lipids in the feces. In this study, a rapid and convenient liquid chromatography method to comprehensively analyze fecal lipids in a single injection was developed. An evaporative light-scattering detector (ELSD) for routine analysis or atmosphere pressure chemical ionization tandem mass spectrometry [(+)APCI-MS/MS] for structural confirmation and peak purity was used. The method was applied to characterize lipid components of feces from hamsters fed high-fat diets with either 5% microcrystalline cellulose or 5% hydroxypropyl methylcellulose (HPMC) fibers, to test the effect of HPMC on lipid metabolism. HPMC is a nonfermentable, soluble cellulose fiber. The fecal lipid components identified using this method includes two secondary bile acids, deoxycholic acid, lithocholic acid, and neutral sterols including cholesterol, coprostanol, stigmastanol, and sitosterol. The profile of fecal lipid components was compared between two groups. It was found that the bile acid excretion was increased 2-fold in HPMC-fed hamsters. More interestingly, diacylglycerides and triacylglycerides were detected in feces from hamsters on HPMC-included high-fat diets. We believe that this is the first report of excretion of acylglycerides following neutral soluble fiber feeding.  相似文献   

6.
Thirty-five samples of cow feces (cowpat and cow manure) and pig slurries subjected to different treatment processes and different storage times before land spreading were extracted and analyzed by gas chromatography-mass spectrometry to determine their fecal stanol profiles. The fresh pig slurry data presented here increase considerably the classical range of values obtained for steroid ratios, resulting in an overlap with the range for cow feces. These results lead to the inability to distinguish species source of feces on the basis of steroid ratios alone. The cause of these differences is not known, although it appears likely to be related to differences in the metabolism of animals in relation to their age and/or variations in diet, rather than to secondary mechanisms of steroid degradation during storage or/and treatment of the feces. Nevertheless, the specificity of steroids to serve as a tool to differentiate cow feces from pig slurries is restored by considering the fecal stanol profile, notably, the six most diagnostic stanol compounds, which are 5β-cholestan-3β-ol (coprostanol), 5β-cholestan-3α-ol (epicoprostanol), 24-methyl-5α-cholestan-3β-ol (campestanol), 24-ethyl-5α-cholestan-3β-ol (sitostanol), 24-ethyl-5β-cholestan-3β-ol (24-ethylcoprostanol), and 24-ethyl-5β-cholestan-3α-ol (24-ethylepicoprostanol). In this study, chemometric analysis of the fingerprint of these six stanols using principal components analysis (PCA) distinguished pig slurries from cow feces. The application of PCA to the stanol profiles, as developed in this study, could be a promising tool for identifying the animal source in fecal contamination of waters.  相似文献   

7.
The European Union has introduced a new bathing water directive where future classification of recreational waters will be based on the microbial parameters Escherichia coli, and intestinal enterococci. Introduction of enterococci as a new quality parameter may pose a challenge in some areas because relatively less is known about these organisms compared to E. coli. In the present study, the relative abundance of intestinal enterococci, E. coli, and ten fecal sterol and stanol biomarkers were investigated in water and sediment at two estuarine beach sites affected by fecal pollution. In the bathing water, enterococci were relatively more abundant at low E. coli concentrations. In the sediment, enterococci were generally more abundant than E. coli with surface concentrations between 1.0?×?102 and 4.5?×?103 CFU cm?3. Enterococci populations were relatively similar in water and sediment, and were phenotypically different from that of nearby pollution sources. The putative human specific genetic marker esp in Enterococcus faecium was not detected in water or sediment samples despite occasional inputs of human waste from storm water overflows. Sterol and stanol profiles suggested a direct link between water and sediment pollution profiles on days with wind conditions that facilitated resuspension. Sediment resuspension may occur at wind speeds exceeding 6–8 m s?1, and could contribute significantly to enterococci concentrations in the overlying water. The study emphasized that recontamination of the water column due to wind induced resuspension should be considered when evaluating indicator levels and microbial hazards in estuarine recreational waters.  相似文献   

8.
Environmental problems many times could evolve when manure-containing pathogens are distributed into an open environment with no effort made to reduce the content of pathogens or limit their movement in the environment. Wind, surface flow, and subsurface flow can all carry enough pathogens to receiving waters to exceed water quality standards. This study was conducted to assess the microbiological quality of water associated with animal-based agriculture in the sub-basin of Pinhal River located in the rural area of Concordia, Santa Catarina, Brazil. Six sampling points representing different agricultural land uses (LU1—dairy cattle; LU2—without animals; LU3—dairy + pigs + poultry + crops; LU4—pigs + poultry + crops; LU5—dairy + pigs + poultry + crops + human; and LU6—dairy+pigs+crops) along the Pinhal River sub-basin (north to south) were sampled biweekly from August 2006 to December 2008. Concentrations of fecal coliforms and Escherichia coli varied significantly (p?≤?0.05) with land use (LU), but there was no interaction effect of LU, season, and time. Water samples from the catchment area of LU1 had the highest concentration of fecal coliforms (4,479?±?597 CFU ml?1) when compared with other catchment areas. Catchment area associated with LU2 (no animal) had the lowest concentrations of fecal coliforms (39.2?±?5.2 CFU ml?1). With the exception of LU2 (control site), all the maximum concentrations of E. coli exceeded the single maximum allowable concentration for E. coli (100 CFU ml?1). When LU1 was compared with other catchment areas (LU3, 50%; LU4, 67%; LU5, 58%; and LU6, 44%), it had the lowest counts (39%) of Salmonella sp. Our results suggest that spatial pattern of bacterial water quality is evident, which can be linked to the different land uses and associated practices (present or absent of animal activities). Therefore, varying responses associated with the different land uses would be critical in identifying the importance of different sources of bacteria in the catchment area and the mechanisms transferring them.  相似文献   

9.
To test whether manure amendment in soil reduces plant uptake of persistent organic pollutants, carrot (Daucus carota L.) was used as a model plant and 2,2′,4,4′-tetrabrominated diphenyl ether (BDE-47) was selected as a model persistent organic pollutant to conduct a pot experiment with contaminated soil amended by composted pig manure. The results showed that the concentration and bioconcentration factors (BCFs) of BDE-47 in the edible part of carrot significantly decreased from 229.7?±?28.2 to 43.4?±?20.4 ng g?1 and from 1.86?±?0.5 to 0.15?±?0.03, respectively, with increasing composted pig manure dose from 0 to 4%. Organic matter (OM) derived from composted pig manure played a dominant role in reducing persistent organic pollutant bioavailability in soil. Composted pig manure amendment and carrot cultivation jointly altered the bacterial community composition in soil, especially the rhizosphere. Rhizodegradation of BDE-47 was enhanced from 8.6 to 28.5% with increasing composted pig manure dose from 0 to 4%, corresponding to increased soil microbe diversity and polybrominated diphenyl ether-degrading bacteria (Sphingomonas, etc.) abundance in the rhizosphere. This study is the first, to the best of our knowledge, to provide an effective agronomic strategy of manure amendment to reduce plant uptake and simultaneously enhance rhizodegradation of persistent organic pollutants in soil, and thus potentially reduce human health risks through dietary intake.  相似文献   

10.
针对集约化养殖中大量使用含Zn饲料添加剂及其在畜禽粪便中的残留问题,采集北京6个郊区县集约化养殖场208个猪、奶牛、鸡饲料样品和204个粪便样品,分析测定了其中Zn含量。结果表明,北京地区集约化养殖饲料和粪便中Zn含量差异很大,猪饲料和猪粪中Zn含量远高于奶牛和鸡。猪、奶牛、鸡饲料中Zn的含量范围分别为72.77~3170.37mg·kg^-1、13.63—471.39mg·kg^-1、32.64—344.67mg·kg^-1,平均含量分别为347.57、86.44、138.76mg·kg^-1;猪、奶牛、鸡粪便Zn的平均含量分别为2333.97、119.41、391.01mg·kg^-1,含量范围分别在458.21—14031.79、10.36~502.39、73.15~678.91mg·kg^-1之间。猪饲料和猪粪Zn超标率分别为9.3%和15.0%,奶牛、鸡的饲料和粪便均未超标。畜禽粪便中Zn含量与其饲料中zn含量之间呈显著或极显著正相关(P〈0.05),猪、奶牛、鸡粪便中Zn的平均含量分别是其饲料的6.7倍、1.4倍、2.8倍,表现出一定的“浓缩”效应,其中断奶仔猪饲料和粪便中zn的平均含量最高,分别为645.37和5133.64mg·kg^-1,“浓缩系数”高达6.61。高Zn含量的畜禽粪便在土地利用时可能会带来土壤污染风险。  相似文献   

11.
在静态通气条件下,分别以养殖场鸡粪、猪粪、牛粪为材料,加入麦秸作为调节物质,研究了加入外援菌剂堆腐过程堆体脱氢酶活性变化及其与温度的关系。结果表明,添加微生物菌剂使得堆体温度迅速上升,整个堆肥过程中的堆体温度高于对照,在堆肥的第1~2 d进入高温期,且高温阶段持续时间延长为16~20 d;对照处理在堆腐的4~5 d后进入高温期,持续时间较短仅为7~8 d。3种物料脱氢酶活性大小相比较,加菌剂处理, 牛粪 [H+ 29.32 μL/(g·d)]鸡粪 [H+ 25.66 μL/(g·d) ]≈猪粪 [H+ 25.34 μL/(g·d)],脱氢酶高峰出现的时间以牛粪 (6 d) 鸡粪(12 d) 猪粪(14 d) 。CK处理均在堆肥后第10 d脱氢酶活性达到最高,3种物料的脱氢酶大小的顺序为牛粪 [H+ 24.62 μL/(g·d)] 鸡粪 [H+ 21.6 μL/(g·d)] 猪粪 [H+ 18.62 μL/(g·d)]。加菌剂处理在高温堆肥初期过高的温度不利于土壤微生物的活动,因此在温度大于60℃以上时,脱氢酶的活性与温度呈直线负相关,此后脱氢酶活性与温度成显著性直线正相关;对照处理升温较缓慢,酶活性和温度增长同步,整个堆腐期间的脱氢酶活性与温度成显著性直线正相关。  相似文献   

12.
The goal of this work was to investigate the occurrence of emerging contaminants in drinking water of the city of Campinas, Brazil. Tap water samples were analyzed using SPE-GC-MS for 11 contaminants of recent environmental concern. Six emerging contaminants (stigmasterol, cholesterol, bisphenol A, caffeine, estrone, and 17β-estradiol) were found in the samples. The latter two were detected only during the dry season, with concentrations below quantification limits. Stigmasterol showed the highest average concentration (0.34?±?0.13?µg L?1), followed by cholesterol (0.27?±?0.07?µg L?1), caffeine (0.22?±?0.06?µg L?1), and bisphenol A (0.16?±?0.03?µg L?1). In Campinas, where surface drinking water supplies receive large amounts of raw sewage inputs, the emerging contaminants levels in drinking waters were higher than median values compiled for drinking and finished water samples around the world.  相似文献   

13.
Citrus bergamia Risso et Poiteau fruits have been traditionally utilized, in Calabria (Italy), as a popular remedy for their hypolipidemic properties. C. bergamia juice total phenol content (2474.35+/-38 microg/mL) was evaluated by the Folin-Ciocalteu method; moreover, HPLC analysis led to the identification of naringin (520 ppm), neoeriocitrin (370 ppm), and neohesperidin (310 ppm). The present study was designed to investigate the hypolipidemic effects of C. bergamia juice and its protective effect on liver of hyperlipidemic rats. Chronic administration of C. bergamia (1 mL/rat/day) provoked a significant reduction in serum cholesterol, triglycerides, and low-density lipoprotein (LDL) levels and an increase in high-density lipoprotein (HDL) levels; moreover, histopathological observations showed, in rats submitted to C. bergamia treatment, a protection of hepatic parenchyma. In addition, fecal neutral sterols and fecal bile acid excretion was found to be increased after C. bergamia treatment. These results suggest that the hypocholesterolemic effect of C. bergamia may be mediated by the increase in fecal neutral sterols and total bile acids excretion. In addition to the hypolipidemic effect, the juice shows radical scavenging activity in the diphenylpicrylhydrazyl (DPPH) test; probably the two effects are related. These observations suggest that the positive intake of C. bergamia may reduce the risk of some cardiovascular diseases through its radical scavenging function and hypocholesterolemic action.  相似文献   

14.
To determine nitrogen (N) fate and environmental impact of applying anaerobic digestion slurry (ADS) to rice paddy (Oryza sativa L.), a field experiment was established using three treatments based on contrasting N application rate. The ADS (with ammonium-N accounting for >80 % of total N) treatment at a conventional application rate of 270 kg N?ha?1 was compared to a negative control (no N fertilizer) and a positive control of urea applied at 270 kg N?ha?1. The N budget showed the following distribution of applied N from ADS and urea: 41.3?±?5.1 % for ADS and 36.6?±?4.4 % for urea recovered by the rice plant (including straw, grain, and root), 16.4?±?3.7 % for ADS and 7.4?±?1.8 % for urea lost via ammonia volatilization, 0.26?±?0.15 % for ADS and 0.15?±?0.12 % for urea lost by direct N2O emission, 1.9?±?0.5 % for ADS and 2.3?±?0.8 % for urea leached downward, 0.70?±?0.15 % for ADS and 0.67?±?0.12 % for urea discharged with floodwater drainage, and 39.4?±?8.4 % for ADS and 53.0?±?9.1 % for urea retained by soil or lost by N2 emission. Compared to urea application, ADS application impacts the environment mainly through gaseous N losses rather than water N losses. ADS application had a positive impact on rice grain yield and reduced chemical fertilizer use. Considering the wide distribution of paddy fields and the ever-increasing quantities of ADS, ADS may serve as a valuable N source for rice cultivation, although mitigating ammonia and N2O losses should be further investigated.  相似文献   

15.
The speciation of mercury (Hg) in Minamata Bay (Japan) was studied over a 2-year period (2006?C2008). Concentrations of dissolved total Hg, dissolved methylmercury (MeHg), particulate total Hg, and suspended solids were 0.43?±?0.14 ng/l (mean?±?standard deviation), 0.10?±?0.06 ng/l, 3.04?±?2.96 ng/l, and 5.94?±?2.10 mg/l, respectively. Correlations between concentrations of particulate total Hg and suspended solids at four depths (surface: 0 m; mid-depth: ?6 m, ?10 m; and bottom +1 m layer) were only significant in the bottom +1 m layer. The mean dissolved MeHg concentration and the ratio of dissolved MeHg to dissolved total Hg were considerably higher in summer compared to other seasons. The data suggest that bottom sediment was not the sole source of MeHg, and that MeHg may be produced in the water column by the conversion of divalent Hg eluted from resuspended bottom sediment. The correlation between seawater characteristics such as salinity, temperature, dissolved oxygen (DO), and dissolved MeHg concentration indicates that Hg methylation could be influenced by the heterotrophic activity of microorganisms in the seawater. In particular, inverse correlations were observed between DO, salinity, and MeHg concentration. However, dissolved MeHg concentrations did not correlate with seawater characteristics such as pH or chlorophyll-a.  相似文献   

16.
Acute toxicity of Pb to the water flea; (Daphnia sp) and Copepod, (Cyclop sp) both important component of zooplankton diet of fish was determined by static assay. A positive relationship between percentage mortality and exposure concentration was found in all tests. Mean 24-h LC50, 48-h LC50 and 96-h LC50 values were 2.51?±?0.0.04 mg l?1, 1.88?±?0.06 mg l?1 and 1.65?±?0.19 mg l?1 for Daphnia spp and 3.11?±?0.03 mg l?1, 2.97?±?0.05 mg l?1 and 2.61?±?0.09 mg l?1 for Cyclop spp, respectively. For all tested species did the LC50 values decrease with time; the decrease was more marked for Daphnia spp. Observed symptoms include spiral movement followed by change of body colour to white and rapid disintegration of the skin. The Daphnia spp. appear to be more sensitive to Pb poison than Cyclop spp. The results showed that concentrations of Lead (Pb) in excess of 0.19 mg l?1 and 0.30 mg l?1 can be potentially harmful to Daphnia magna and Cyclop spp respectively.  相似文献   

17.
We determined normal plasma butyrylcholinesterase (BChE), carboxylesterase (CbE using ??-NA substrate), and glutathione S-transferase (GST) activities in Caiman latirostris and Phrynops hilarii to obtain reference values for organophosphorus (OP) pesticide monitoring. BChE and CbE sensitivity to malaoxon was also evaluated. C. latirostris (N?=?12; six males and six females) and P. hilarii (N?=?12; seven males and five females) were obtained from the programs Yacaré (Entre Ríos Province, Argentina) and Zoo of Córdoba (Córdoba Province, Argentina). Mean total (female and male) plasma BChE activity was significantly different between reptile species, ranging between 0.337?±?0.085???mol?min?1?ml?1 of plasma for C. latirostris and 0.251?±?0.070???mol?min?1?ml?1 of plasma for P. hilarii. However, plasma CbE (??-NA) and GST activities were significantly higher in P. hilarii (4.81?±?1.00 and 0.145?±?0.045???mol?min?1?ml?1 of plasma, respectively) than in C. latirostris (0.57?±?0.20 and 0.059?±?0.013???mol?min?1?ml?1 of plasma, respectively). No significant differences in B-esterase and GST activities were detected between sexes, except CbE (??-NA) for C. latirostris. IC50 values for BChE and CbE (??-NA) suggested different sensitivity levels between species and between sexes. The results demonstrate that plasma esterase activity varied between species, but not between sexes (except CbE for C. latirostris). The in vitro inhibition tests indicated that CbE (??-NA) is more sensitive to inhibition than BChE. C. latirostris may be the reptile species most vulnerable to field pesticide exposure because this reptile presents the lowest CbE activity levels and its B-esterase levels seem more sensitive to OP.  相似文献   

18.
Extraction and analysis methods have been developed for the detection of the following four antibacterial agents and two natural estrogens in treated municipal wastewater sludge and commercial compost: sulfamethoxazole (SMX), sulfadimethoxine (SDM), tetracycline (TET), oxytetracycline (OXY), estrone (E1), and 17??-estradiol (E2). The antibiotics and estrogens were extracted from secondary sludge and mixed compost using ultrasonic solvent extraction. Citric acid (pH?4.7) and methanol were used as extraction buffer, followed by tandem-solid-phase extraction cleanup, strong anion exchange?+?hydrophilic?Clipophilic balance for antibiotics and CarboPrep/NAX for estrogens. For quantification, two different methods were employed, using HPLC?CMS/MS, with an electrospray ionization source for antibiotics and an atmospheric-pressure chemical ionization source for estrogens. Recoveries were 11?C31% for the sulfonamides (SMX and SDM) and tetracyclines (TET and OXY) and 30?C59% for the estrogens (E1 and E2) over the entire method. Limits of detection for the extraction method were in the nanogram per gram range for dry weight sludge and compost samples. Neither of the two sulfonamide antibiotics was detected in secondary sludge or mixed compost samples. Estrogens were found in compost in amounts of 160?±?65?ng/g (E1) and 21?±?3?ng/g (E2), but not in sludge. The tetracyclines, as well as what is believed to be the 4-epimer of OXY, were found in both sludge and compost in amounts of 1.57?±?0.67 and 2.95?±?0.42???g/g (TET), 0.56?±?0.12 and 6.51?±?0.52???g/g (OXY), and 7.60?±?1.68 and 1.35?±?0.24???g/g (4-epi-OXY), respectively. These results indicate that sorption-prone compounds are not removed during the wastewater treatment process and can persist through sludge digestion and that the composting process does not sufficiently eliminate these particular contaminants. Thus, biosolids (even composted) are an additional source of drug residues leaching into the environment, and it must be considered while using biosolids as fertilizer.  相似文献   

19.
Comamonas sp. UVS was able to decolorize Reactive Blue HERD (RBHERD) dye (50 mg L?1) within 6 h under static condition. The maximum dye concentration degraded was 1,200 mg L?1 within 210 h. A numerical simulation with the model gives an optimal value of 35.71?±?0.696 mg dye g?1 cell h?1 for maximum rate (Vmax) and 112.35?±?0.34 mg L?1 for the Michaelis constant (Km). Comamonas sp. UVS has capability of decolorization of RBHERD in the presence of Mg2+, Ca2+, Cd2+, and Zn2+, whereas decolorization was completely inhibited by Cu2+. Metal ions also affected the levels of biotransformation enzymes during decolorization of RBHERD. Comamonas sp. UVS was also able to decolorize textile effluent with significant reduction in COD. The biodegradation of RBHERD dye was monitored by UV–vis spectroscopy, FTIR spectroscopy, and HPLC.  相似文献   

20.
The effect of waterborne zinc on survival, growth, and feed intake of Indian major carp, Cirrhinus mrigala (Hamilton), advanced fry was studied under laboratory condition. Survival rates of C. mrigala advanced fry (2.71?±?0.49 g) after 30 days exposure to control (0.01), 0.03, 0.06, 0.10, and 0.15 mg/L zinc using the static renewal method in freshwater at pH 7.3?±?0.2, temperature 26?±?2°C, and total hardness 114?±?16 mg/L as CaCO3 were 100%. Growth of the fish exposed to 0.10 and 0.15 mg/L of zinc was significantly lower (P?<?0.05) than in control (0.01), 0.03, and 0.06 mg/L of zinc after 30 days of exposure. However, there were no significant differences (P?>?0.05) in fish growth between 0.03 and 0.06 mg/L zinc concentrations. Feed intake rates were significantly (P?<?0.05) reduced in the fish exposed to 0.10 mg/L and higher levels of zinc. The zinc accumulation in the whole body of the fish increased with increasing concentrations of the metal.  相似文献   

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