Sulphate uptake

The weight of the evidence seems to suggest that the antirheumatic action of acetylsalicylic acid and phenylbutazone is not mediated through stimulation of the pituitary-adrenal axis. If the inhibition of sulphate uptake by... 

Von Arb, C., Mueller, C Ammann, K., Brunold. Ch. 1990. Lichen Physiology and air pollution. II. Statistical analysis of the correlation between SO, NO2, NO and O), and chlorophyll content, net photosynthesis, sulphate uptake and protein synthesis of Parmelia sulcata Taylor. New Phytol. 115, 43I-M37. 

The influence of the artificial temperature gradient is much more pronounced here notwithstanding the much smaller value of AT/At than in the case of water. When heat-killed cells are used, the artificial temperature gradient does not seem to produce detectable alterations in sulphate uptake, as already found for dead cells using water as permeant. 

Transporters that have high affinity for sulphate (HAST) this is likely to be the primary transporter involved in sulphate uptake from the soil, and is expressed mainly in roots with a K i for sulphate of 7-10 pM. HAST is also considered to be involved in selenate uptake and... 

BARTON L.L. and RUOCCO J.J. 1981. Soluble humic complexes and sulphate uptake by Aspergillus niger. Soil Biology and Biochemistry, 13, 435-437. 

This study assesses the uptake of persistent organic pollutants (a-Endosulfan, P-Endosulfan and Endosulfan sulphate) from lettuce. The lettuce plants were grown on compost that had previously been contaminated at 10 and 50 J.g/g. 

A strain of Azotobacter vinelandii was cultured in a 15 m3 stirred fermenter for the production of alginate. Under current conditions the mass transfer coefficient, kLa, is 0.18 s. Oxygen solubility in the fermentation broth is approximately 8 X 10 3 kgm-3.9 The specific oxygen uptake rate is 12.5 mmol g 1 h. What is the maximum cell density in the broth If copper sulphate is accidentally added to the fermentation broth, which may reduce the oxygen uptake rate to 3 mmol g 1 h 1 and inhibit the microbial cell growth, what would be the maximum cell density in this condition ... 

Wells, J.M. and D.H.S. Richardson. 1985. Anion accumulation by the moss Hylocomium splendens uptake and competition studies involving arsenate, selenate, selenite, phosphate, sulphate and sulphite. New Phytol. 101 571-583. 

Ghromate adsorption by iron oxides is suppressed by a large excess of carbonate or silicate species. Gompetition between silicate and borate adsorption on ferrihydrite was reported by McPhail et ak (1972). Low levels of sulphate suppress uptake of phthalic and chelidimic acids by goethite (Ali Dzombak, 1996 a). 

Trace metal adsorption on goethite is reportedly increased by the presence of sulphate ions (Balistrieri and Murray, 1982). Arsenate and antimony oxyanions enhance uptake of cobalt on ferrihydrite and hematite, respectively (Benjamin and Bloom,... 

Variations in the 8 34S values for plants have been summarised by Krouse et al. (1991), these range from -20 to +34%o and are comparable to those reported in sedemintary rocks. It has been found that the sulphur uptake by the plant is mainly from soil sulphate where ambient S02 levels are low. In some cases ambient S02 dominates and the 8 34S values are close to those of the S02. These two uptake mechanisms are a factor in the differing isotope ratios in different parts of an individual plant (Chukhrov et al., 1978). Thus sulphur isotope ratios are helpful in the determination of sulphur sources in the environment. 

Another aspect from the drug delivery point of view is the combined use of different types of permeation enhancers in the same formulation. Whitehead et al. (2008), for instance, could show a synergistic effect of binary combinations of hexylamine and chembetaine and ternary combinations of sodium laureth sulphate, decyltrimethyl ammonium bromide and chembetaine on the uptake of 70 kDa dextran from Caco-2 monolayer while inducing very little toxicity in Caco-2 cells. 

The comparison of iron(II) and iron(III) uptake by mammalian intestine has recently been the focus of intense research effort. In a study of 14 different iron preparations in man, Dietzfelbinger [100] showed that the iron(III) preparations, without exception, had a lower bioavailability than iron(II) sulphate and were therefore of dubious therapeutic efficacy. Unfortunately, orally administered iron(II) sulphate generates hydroxyl radicals in the gastrointestinal tract of mammals [101], This property, together with the associated acidity of iron(II) sulphate, may cause irritation and damage to the mucosa. A wide range of side effects have been reported for iron(II) sulphate [102]. Thus, should an efficiently absorbed iron(III) complex be identified, it would be of therapeutic benefit. 

A2. Adams, J. B., Effect of chondroitin on the uptake of radioactive sulphate into chondroitin sulphate. Biochim. Biophys, Acta 32, 559-561 (1959). 

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