68 research outputs found
Effect of the detergent alkylbenzene sulphonate (ABS) on hepatopancreas of the shrimp Crangon crangon L.
Shrimps Crangon crangon L., acclimated in the laboratory for 24 h in brackish water (7â° salinity), were incubated in solutions of anionic detergent alkylbenzene sulphonate (ABS) in concentrations of 5 - 50 ppm. After 24 h or 96 h of incubation, preparations of hepatopancreas were stained and examined by light or transmission electrone microscopy. The light microscopy examination revealed a flattening of the duct cells, pyknotic nuclei in these cells, fine granular secretions in the ducts of the gland, and cellular infiltration. The transmission electron microscopy examination revealed an impairment and destruction of the lysosomal and mitochondrial membranes of the hepatopancreas cells in the shrimps exposed to alkylbenzene sulphonate
Influence of crude oil and detergents on the concentration of some ions in hemolymph of the shrimp Cragon cragon L. and the crab Rhithropanopeus harrisi Gould
Solutions of detergent or crude oil of 10 ppm, 50 ppm, and 100 ppm after 48-96 hours of exposure induce significant changes in the ionic composition of the hemolymph of the shrimp Crangon crangon and the crab Rhithropanopeus harrisi. The concentrations of sodium, calcium, and chloride ions decrease, whereas the concentration of potassium increases in both species exposed to both pollutants. - The magnesium ion concentration decreases in the hemolymph of the shrimp incubated in solutions of detergent and in the crab incubated in the water containing crude oil. - lt is suggested that changes of the ionic composition of the hemolymph of the studied shrimps and crabs under influence of both pollutants are possibly brought about by alteration of cell membrane permeability and action on some enzyme activities
Purification and properties of soluble arylsulphatases isolated from hepatopancreas of the shrimp Crangon crangon L.
Arylsulphatase A and B were isolated from the hepatopancreas of the shrimp Crangon crangon L. after 7 days incubation in 50 ppm of detergent "SOLO". Arylsulphatase A, B-1 and B-2 were isolated from the hepatopancreas of the shrimp C. crangon L. incubated in pure brackish water (salinity 7â°). - Heavy and light fuel oil added to the enzyme in vitro in conc. of 2.0% inhibit the activity of arylsulphatase A in greater degree than arylsulphatase B (14.4% and 5.5% respectively). - Detergent "SOLO" (mixture of nonionic and anionic detergents) in the conc. of 0.5% inhibits for 58% arylsulphatase A and for 91% arylsulphatase B, whereas in conc. of 2.0% it inhibits arylsulphatase A for 91.7% and arylsulphatase B for 100%
13C-NMR Assessment of the Pattern of Organic Matter Transformation during Domestic Wastewater Treatment by Autothermal Aerobic Digestion (ATAD)
The pattern of biodegradation and the chemical changes occurring in the macromolecular fraction of domestic sludge during autothermal thermophilic aerobic digestion (ATAD) was monitored and characterised via solid-state 13C-NMR CP-MAS. Major indexes such as aromaticity, hydrophobicity and alkyl/O-alkyl ratios calculated for the ATAD processed biosolids were compared by means of these values to corresponding indexes reported for sludges of different origin such as manures, soil organic matter and certain types of compost. Given that this is the first time that these techniques have been applied to ATAD sludge, the data indicates that long-chain aliphatics are easily utilized by the microbial populations as substrates for metabolic activities at all stages of aerobic digestion and serve as a key substrate for the temperature increase, which in turn results in sludge sterilization. The ATAD biosolids following treatment had a prevalence of O-alkyl domains, a low aromaticity index (10.4%) and an alkyl/O-alkyl ratio of 0.48 while the hydrophobicity index of the sludge decreased from 1.12 to 0.62 during the treatment. These results have important implications for the evolution of new ATAD modalities particularly in relation to dewatering and the future use of ATAD processed biosolids as a fertilizer, particularly with respect to hydrological impacts on the soil behaviour
Test of Some Aspects of Modelling the Sorption of Hydrophobic Compounds in Soils
A study was carried out on the sorption of the herbicide linuron in podzolic soil (one of the typical soils of Poland), the sorption isotherms being obtained using batch equilibrium studies. Modelling sorption phenomena involving the interactions of chemicals and particularly herbicides is very difficult because of the strong heterogeneity of the soil matrix. The present work presents the results of applying the most common models, i.e. Freundlich and Linear, as well as the newer concept of the Dual Reactive Domain model. The data obtained were validated using various statistical and chemometric methods. The results suggest that applying the non-linear least-squares method to obtain isotherm parameters gave a much better description of the sorption phenomena than often obtained using linear transformations of the adsorption equations. The study also showed that appropriate weighting schemes should be included in any model calculations. To test the goodness-of-fit of the model to the experimental data both the correlation coefficient and the Residual Root Mean Square Error were obtained. The models were also compared using the Extra Sum of Squares Principle statistical test
Influence of light, heavy and crude oil on the mortality of shrimps Cragon cragon L. under laboratory conditions
Shrimps (Crangon crangon L.) were exposed to 5, 7.5, 10, 25, or 50 ppm of light fuel oil, heavy fuel oil or crude oil at 15° C or 20° C with aeration. The mortality was recorded. It was found that light fuel oil was the most toxic and crude oil the least toxic
Influence of an anionic detergent (alkylbenzene sulphonate) on enzymes, moulting cycle and survival in the shrimp Crangon crangon L.
Shrimps Crangon crangon L. were exposed to 5, 7.5, 10, 25 and 50 ppm of the anionic detergent alkylbenzene sulphonate (ABS) added to brackish water (7Ⱐsalinity). The animals were incubated in these solutions from one to nine days at 15° C or 20° C. After 24 h and 108 h of incubation the activities of arylsulphatase (E.C. 3.1.6.1 ), acid phosphatase (E.C. 3.1.3.2) and cathepsin D (E.C. 3.4.4.23) were assayed in homogenates of the hepatopancreas. The influence of the detergent ABS on the moulting cycle of the shrimps was also investigated. The activity of all acid hydrolases assayed descreased by 20 % to 50 % in the experimental shrimps, depending on concentration of the pollutant, as compared with the control group. The moulting cycle of the shrimps exposed to the action of the detergent was shortened from 31 % to 51 %, and the body weight during one moulting cycle was reduced by 24 % to 36 %. Survival times were reduced in the animals exposed to the action of the detergent. Total mortality of the shrimps occurred after 194 h, in 5 ppm of ABS at 15° C and after 108 h in 50 ppm. The 96 h LC50 for shrimp Crangon crangon L. under laboratory conditions was estimated as 27 ppm of alkylbenzene sulphonate
Inter-laboratory validation of liquid chromatographyâtandem mass spectrometry multi-mycotoxin determination in animal feed â method transfer from the reference laboratory to regional laboratories
The results are presented of the inter-laboratory validation of a liquid chromatographyâtandem mass spectrometry method for the determination of eight mycotoxins (aflatoxin B1, deoxynivalenol, fumonisin B1, fumonisin B2, ochratoxin A, toxin T-2, toxin HT-2 and zearalenone) in animal feeds
Adsorption of Ammonium Ions onto a Natural Zeolite: Transcarpathian Clinoptilolite
A study was carried out of ammonium ion sorption from synthetic aqueous solutions by Transcarpathian clinoptilolite, a natural zeolite, under static conditions. The main physical properties of the clinoptilolite and the basic parameters of its porous structure were determined. Values of the specific surface area and of the pore volume occupied by sorbed substances were calculated using the relative moisture content established and the maximum sorption capacity exhibited towards ammonium ions as well as a nitrogen adsorption/desorption method. Ammonium ion sorption by the zeolite appeared to be complete within 24 h for all fraction sizes, initial NH 4 + ion concentration and adsorbate volumes. The amounts of NH 4 + ions sorbed increased with increasing initial NH 4 + concentration and decreasing adsorbate volumes, with the maximum sorption capacity exhibited by the clinoptilolite being 0.64 mequiv/g. The sorption effectiveness decreased somewhat with increasing fraction size. The Langmuir and Freundlich models were applied to the data obtained from the batch studies with the first model exhibiting the more satisfactory correlation coefficient value (0.996 and 0.959, respectively)
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