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The ergosterol content of soil can be used as an indicator of fungal activity. A method has been developed for the extraction and determination of ergosterol in organic soils, as part of a study to assess the correlation between fungal... more
The ergosterol content of soil can be used as an indicator of fungal activity. A method has been developed for the extraction and determination of ergosterol in organic soils, as part of a study to assess the correlation between fungal activity and the sequestration of metal pollutants. The moisture content of the soil affected the extraction process. Four consecutive extractions with methanol removed >95% of the ergosterol that can be obtained from the fresh sample (63% moisture) by exhaustive extraction. By freeze drying the soils prior to extraction (a) up to 35% more ergosterol was extracted after a single extraction, (b) >90% of the recoverable ergosterol was collected in two extractions and (c) the repeatability of the extraction was improved. Storage of soil extracts in the absence of light prevents degradation of ergosterol. A previously reported method for determination of ergosterol by HPLC has been improved by modification of the eluant composition. With 46% methanol/46% acetonitrile/8% dichloromethane, ergosterol was eluted with good resolution approximately 8 min after injection of 20 mul of the extract. The detection limit of the HPLC method was 0.5 mug/ml ergosterol, equivalent to 0.06 mug/g in 25 g fresh soil. Changes in ergosterol contents of peaty soil treated with fungicide, and in samples of the peaty podzol and a humus iron podzol in the vicinity of fungal fruiting bodies, have been determined.
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... On behalf of the scientific community, we communi-cate our deepest sympathy to his wife Dorothy, daughters Jenny and Helen ... His David Littlejohn, Christine Davidson, University of Strathclyde, Glasgow, UK and Jeffrey Bacon,... more
... On behalf of the scientific community, we communi-cate our deepest sympathy to his wife Dorothy, daughters Jenny and Helen ... His David Littlejohn, Christine Davidson, University of Strathclyde, Glasgow, UK and Jeffrey Bacon, Macaulay Institute, Aberdeen, UK On behalf of the ...
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Most analytical methods for butyltins are based on high resolution techniques with complicated sample preparation. For this study, a simple application of an analytical method was developed using High Performance Liquid Chromatography... more
Most analytical methods for butyltins are based on high resolution techniques with complicated sample preparation. For this study, a simple application of an analytical method was developed using High Performance Liquid Chromatography (HPLC) with UV detection. The developed method was studied to determine tributyltin (TBT), dibutyltin (DBT) and monobutyltin (MBT) in sediment and water samples. The separation was performed in isocratic mode on an ultra cyanopropyl column with a mobile phase of hexane containing 5% THF and 0.03% acetic acid. This method was confirmed using standard GC/MS techniques and verified by statistical paired t-test method. Under the experimental conditions used, the limit of detection (LOD) of TBT and DBT were 0.70 and 0.50 microg/mL, respectively. The optimised extraction method for butyltins in water and sediment samples involved using hexane containing 0.05-0.5% tropolone and 0.2% sodium chloride in water at pH 1.7. The quantitative extraction of butyltin compounds in a certified reference material (BCR-646) and naturally contaminated samples was achieved with recoveries ranging from 95 to 108% and at %RSD 0.02-1.00%. This HPLC method and optimum extraction conditions were used to determine the contamination level of butyltins in environmental samples collected from the Forth and Clyde canal, Scotland, UK. The values obtained severely exceeded the Environmental Quality Standard (EQS) values. Although high resolution methods are utilised extensively for this type of research, the developed method is cheaper in both terms of equipment and running costs, faster in analysis time and has comparable detection limits to the alternative methods. This is advantageous not just as a confirmatory technique but also to enable further research in this field.
Research Interests: Multidisciplinary, Sample Preparation, Organotin Compounds, High Performance Liquid Chromatography, High Pressure Liquid Chromatography, and 12 moreEnvironmental quality, High Resolution, Analytical Method, Genetic analysis for qualitative and quantitative traits of crop plants, Gas Chromatography/mass Spectrometry, Extraction Method, Acetic Acid, Environmental Pollutants, Certified Reference Material, Sensitivity and Specificity, Sodium Chloride, and Science Health
Made-up ground collected from layers of a trial pit excavated on a former industrial site was treated with artificial rainwater in a series of column leaching and sorption experiments. Metal mobility and the ability of various layers of... more
Made-up ground collected from layers of a trial pit excavated on a former industrial site was treated with artificial rainwater in a series of column leaching and sorption experiments. Metal mobility and the ability of various layers of material obtained from the pit to act as sources or sinks of potentially toxic elements were assessed. Samples from different layers varied in their abilities to raise the pH of rainwater applied at pH 3.5 and 4.3, and this was reflected in the amounts of metals mobilised by the rainwater as it percolated through the soil column. Material from the top two layers of the pit released cadmium, copper, manganese, lead, nickel and zinc to the aqueous phase, but the lower layers, with higher buffering capacity, were able to resist acidification even when the equivalent of 12 months' rainfall (western UK) was applied. Column sorption experiments confirmed the ability of material from layer 4 (48-50 cm) to take up copper, manganese and zinc. Metals were determined in the leachates by flame and electrothermal atomic absorption spectrometry and principle anions by ion chromatography.
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Methods based on AAS, ICP-AES and XRFS have been developed for determination of Cd, Cr, Cu, Mn, Ni, Pb, V and Zn in soil layers from pits excavated on a redundant industrial site. Samples were dried and sieved, and the < 2 mm... more
Methods based on AAS, ICP-AES and XRFS have been developed for determination of Cd, Cr, Cu, Mn, Ni, Pb, V and Zn in soil layers from pits excavated on a redundant industrial site. Samples were dried and sieved, and the < 2 mm fraction was ground in a ball mill prior to analysis. For ICP-AES and AAS, 1 g sub-samples were digested with aqua regia in a microwave oven. The dry weight detection limits of the analytes were in the range 2–25 μg g for FAAS, 0.003–0.2 μg g for ETA AS and 0.04–1.6 μg g for ICP-AES. When digests of the industrial soils were analysed, calibration with acid-matched standards gave acceptable accuracy for all the analytes, except for Cd when determined by ETAAS (30–40 % suppression). Despite lack of reference materials of industrial origin, analysis of two soil reference materials by these techniques produced concentrations that were within ± 10 % of the certified or recommended values for elements extractable with aqua regia. Direct standard-less analysis of a soil reference material with a portable x-ray fluorescence (P-XRF) analyser gave concentrations for a range of elements that were within a factor of 2 of the certified values. When the XRFS and ICP-AES methods were used to analyse the industrial soils, the concentrations obtained were similar (to within 30%) for Cu, Pb and Zn in most of the samples and for Cr, Mn and Ni in some of the samples. The concentrations of V estimated with the P-XRF analyser were 4 to 7-fold higher than those obtained by ICP-AES. The discrepancies were thought to be caused by spectral enhancement interferences in XRFS. Cadmium was not determined accurately by either ICP-AES or P-XRFS owing to spectral interferences. The work has highlighted the importance of analysing samples from across a site and at different depths, when assessing the extent of metal contamination on industrial land.
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Research Interests: Engineering, Materials Engineering, Earth Sciences, Analytical Chemistry, Food Analysis, and 40 moreBelgium, Biological Sciences, Copepoda, Lipids, Humans, Separation Science, Fatty acids, Solvent Extraction, Ultraviolet, Mycotoxins, Pharmaceutical, Calibration, Animals, Fluoroscopy, Gas Chromatography, Partition Coefficient, High Performance Liquid Chromatography, High Pressure Liquid Chromatography, CHEMICAL SCIENCES, Analytical Method, Food Additives, Liquid Chromatography, Public health systems and services research, Fatty Acid, Reproducibility of Results, Food Contamination, Deoxynivalenol, Gulf War Syndrome, Method Validation, Quntitative Thin Layer Chromatography, Fatty Alcohols, Triticum, Esters, Drug Stability, Zearalenone, Squalene, Wheat flour, Ochratoxin A, Ochratoxins, and Astm
... Since sites contaminated with radiocaesium, and radio silver, were not available, we chose to quantify the translocation of these metals using ... the quantification of fungal biomass in soil using high performance liquid... more
... Since sites contaminated with radiocaesium, and radio silver, were not available, we chose to quantify the translocation of these metals using ... the quantification of fungal biomass in soil using high performance liquid chromatography (HPLC) assay of ergosterol (Anderson et al ...