Sulfur Retention Research Articles

Nutritional value of Townsville stylo (Stylosanthes humilis) and of spear grass (Heteropogon contortus)-dominant pastures fed to sheep. 1. The effect of plant maturity

The voluntary dry matter intake, digestibility and chemical composition of Townsville stylo and of black spear grass cut at different times of the year from a site near Townsville, Queensland, have been examined using penned sheep. Nitrogen, sulphur, and phosphorus intakes and retention in the sheep were measured. The concentrations of N, P, S, Na, and Ca in most cuts of spear grass and P and Na in Townsville stylo were less than the published requirements of animals. With spear grass, digestible dry matter intake declined rapidly from January to April and more slowly from April to October and by mid-March fell below the estimated energy requirements for maintenance of sheep. There was little change in digestible dry matter intake of Townsville stylo between February and May and the level was well above maintenance requirements. Dry matter intake and dry matter digestibility were linearly related but only about 50 per cent of variations in intake were caused by variations in digestibility. Nitrogen balance was linearly related to nitrogen intake, and sulphur balance was linearly related to sulphur intake. Phosphorus intakes were usually less than 1 g P day-l and animals were usually in negative P retention.

The effect of urea in the diet of the early-weaned calf on weight gain, nitrogen and sulphur balance, and plasma urea and free amino acid concentrations

Experiments were conducted with 40 male Friesian calves between 5 and 11 weeks of age. The control diet contained meat meal as the sole protein supplement to grain, and this was replaced by urea to supply 20.1, 39.2, or 55.6% of the dietary nitrogen. The growth rate of the calves, when corrected for digestible dry matter intake, was significantly lower when urea supplied 55.6 % of the dietary nitrogen than when it supplied 0, 20.1, or 39.2% of the dietary nitrogen. The retention of nitrogen and sulphur was lower in the calves given 55.6% of the dietary nitrogen as urea, but the ratio of nitrogen to sulphur retained was constant for all diets. There was a positive correlation between dietary urea nitrogen intake and urea nitrogen concentration in the blood plasma. The urea nitrogen and a-amino nitrogen concentration in the blood plasma was greater in calves at 2 weeks of age than at 11 weeks of age. The concentrations of free glycine, valine, leucine, ornithine, lysine, and histidine in the blood plasma were significantly lower in the calves given the higher levels of urea in the diet.

An estimate of the juvenile sulfur content of basalt

Sulfur analyses by X-ray fluorescence give an average content of 107 ppm for 9 samples of fresh subaerially-erupted oceanic basalt and 680 ppm for 38 samples of submarine erupted basalt. This difference is the result of retention of sulfur in basalt quenched on the sea floor and loss of sulfur in basalt by degassing at the surface. The outer glassy part of submarine erupted basalt contains 800±150 ppm sulfur, and this amount is regarded as an estimate of the juvenile sulfur content of the basalt melt from the mantle. The slower cooled interiors of basalt pillows are depleted relative to the rims owing to degassing and escape through surface fractures. Available samples of deep-sea basalts do not indicate a difference in original sulfur content between low-K tholeiite, Hawaiian tholeiite, and alkali basalt.

EFFECT OF METHIONINE SUPPLEMENTATION POSTERIOR TO THE RUMEN ON NITROGEN UTILIZATION AND SULFUR BALANCE OF STEERS ON A HIGH ROUGHAGE RATION

The effect of post ruminal methionine, dietary methionine or dietary sulfur (S) supplementation on nitrogen retention and S excretion was determined by using three Holstein steers fitted with abomasal cannula in a 3 × 3 Latin square design. The basal diet was fed ad libitum and consisted of ground timothy hay and concentrate in a 5:1 ratio. The diet contained 12% crude protein with urea contributing about 40% of the total nitrogen. Elemental S (0.05%) or methionine (0.22%) was added to the diet while a similar quantity of methionine was infused into the abomasum. Abomasal infused methionine compared with supplemental dietary S or methionine resulted in a 16.6 and 23.9% increase in percent of absorbed nitrogen retained, which was not statistically significant (probability approximately 0.25). Sulfur intake and apparent S digestibility was similar for all treatments; however, urinary S concentration tended to be lower for the elemental S treatment (probability approximately 0.10). Sulfur retention was higher (P < 0.05) with supplementary elemental S than when a similar amount of S was consumed or infused in the form of methionine.

Effect on `Cardinal' Grapes of Position of Sulfur Dioxide Generators and Retention of Gas and Water Vapor in Unvented Containers

`Cardinal9 grapes stored 10 weeks in unvented containers had significantly less decay and significantly more bleaching when packed with top and bottom sulfur dioxide generators than with only a top generator. Increasing the NaHSO₃ dose by adding side generators did not reduce decay further, but did increase bleaching of the fruit. Decay was less and bleaching greater with an unvented polyethylenecoated curtain than with a dry-waxed curtain. Stem drying rates were significantly lower in unvented than in the vented control containers. After 10 weeks of storage an unvented packaging system with top and bottom sulfur dioxide generators, either in a wooden lug with a water-vapor-barrier liner or in a curtain-coated corrugated container, showed a balance of decay control and bleaching injury equal to, or better than, that of the vented control. Needed for decay protection to four months, yet with bleaching within acceptable limits, are generators which release sulfur dioxide at a more constant rate than those now available.

Removal of SO2From Flue Gases Using Carbon at Elevated Temperatures

The interaction of a typical flue gas with active charcoal and bituminous coal char at temperatures between 600 and 800°C and atmospheric pressure has been studied. The SO2 in the flue gas interacts with the carbon to form primarily H2S, COS, and a carbon-sulfur surface complex. H2S and COS break through the carbon bed much in advance of SO2. At 800°C, sulfur retention on the bed exceeds at least 11% before SO2 breakthrough occurs. The reaction of H2S and COS with O2 over active charcoal at 100–140°C to produce sulfur, which deposits on the carbon, has also been studied and found to be feasible. As a result of this study, a new process is outlined for the removal of SO2 from flue gas, with the ultimate conversion

Studies of zinc nutrition in sheep. II*. The influence of zinc deficiency in ram lambs upon the digestibility of the dry matter and the utilization of the nitrogen and sulphur of the diet

Dry matter digestibilities and nitrogen and sulphur balances were compared in ram iambs fed on a zinc-deficient diet containing 2.4 p.p.m. zinc and showing clinical signs of zinc deficiency and in pair-fed ram lambs consuming the same basal diet supplemented with 30 p.p.m. zinc. Dry matter digestibility was similar for the two treatments but both nitrogen retention and sulphur retention were significantly lower in the zinc-deficient animals, although they were consuming and digesting the same amounts of food. Faecal excretion of nitrogen and sulphur was similar in the two groups but the urinary excretion of both these elements was significantly elevated in the zinc-deficient animals. These findings provide further evidence that protein utilization is impaired in zinc deficiency in sheep. *Part I, Aust. J. agric. Res., 1969, 20, 889.

Sulphur metabolism in sheep. IV. The effect of a varied dietary sulphur content on some body fluid sulphate levels and on the utilization of urea-supplemented roughage by sheep

A diet composed of oaten hulls, urea, and mineral mixture was shown to be deficient in sulphur with respect to the nutrition of sheep. Sulphate supplements to the diet increased both crude fibre digestion and nitrogen and sulphur retention. They also increased the concentration of inorganic sulphate in the blood and the levels of total sulphur and total sulphate sulphur in the parotid saliva, but decreased blood urea nitrogen levels and the concentration of residual nitrogen and residual sulphur (protein fraction) in the parotid saliva. The effect of these concentration changes is discussed with particular reference to the feeding of sheep on low sulphur, low nitrogen forages.

FERTILIZER REQUIREMENTS OF STEEPLAND SOILS IN THE WANGANUI AND RANGITIKEI DISTRICTS

A study of a suite of stcepland soils in both the Wanganui and Rangitikei districts showed that the major nutrients limit,ing the growth of clovers were phosphorus and sulphur. To remedy the phosphate deficiency, 4 cwt of superphosphate per acre was required initially and by applying this amount of superphosphate the sulphur deficiency would also be rectified. Owing to the very low sulphur retention capacities of the soils, the superphosphate should be apphed in the spring. The phosphate retegtion.values indicate that the maiatenance superphosphate dressingi are likely to be 11/z to 2 cwt per acre annually. The initial responses to lime were small and would not be economic. Molybdenum was not required in the development of these soils.

Solid complexes of carbon and sulphur—I. Sulphurised polymer carbons

An account is given of a comparative examination of the formation and behaviour of sulphur carbons resulting from the reaction of representative polymer carbons with sulphur or hydrogen sulphide. Non-stoichiometric retention of sulphur was accompanied by reasonably systematic changes in ESR shown by the carbons; but this behaviour was distinctly less systematic in the reaction with hydrogen sulphide than with sulphur vapour. The thermal stability and chemical behaviour of the sulphurised carbons, including desulphurisation by hydrogen, was also examined. It was concluded that the sulphurised carbons probably comprised chiefly carbon-sulphur complexes, in the formation of which the nature and availability of the surface and the presence of unpaired spin centres and of hydrogen played an important part. Indications of the close association between loss of unpaired spin centres and sulphur retention also suggested that coupling of the reacting sulphur with spin centres present initially or formed by dehydrogenation, was a feature of the carbon-sulphur vapour reaction. It is suggested that the bonding chiefly concerned is akin to that in thioethers or disulphides, and may effectively form peripheral heterocyclic structures on the exposed layer lattices in the carbon surface, or sulphur bridges between neighbouring layers. This suggestion conforms with the general observation that the most disordered carbons are most susceptible to sulphurisation.

Studies on the retention of sulphur by yellow-brown pumice soils

Abstract Forty yellow-brown pumice soils were examined for sulphur retention, using a laboratory leaching and incubation technique. Leaching losses of sulphate from added superphosphate ranged from 33% to 100% of that applied. Comparative sulphur losses from four out of five yellow-brown loams examined were much smaller (2-6% of the amount applied). On these volcanic ash soils, the concentration of allophane A appears to be an important factor in sulphate retention.

Excretion of sulfur during healing of experimental wounds.

SummaryThe effect of wounding on metabolism of the sulfur amino acids was studied by following the excretion of sulfur in normal and wounded rats. After wounding, there is a relative retention of sulfur, even though a greater amount of nitrogen than normal is excreted. Studies with S35 labeled cystine and methionine indicated that the metabolism of these amino acids is greater in wounded than in normal animals.

Effect of cystine and methionine on healing of experimental wounds.

SummaryThe effect of methionine and cystine on the healing index of standard experimental wounds in rats was determined. Since both amino acids have the same effect, per equivalent of sulfur, it is concluded that methionine is converted to cystine before being used in the healing process. When the utilization of methionine is blocked by ethionine, cystine is ineffective, indicating that some methionine, per se, is required for the healing of wounds. There appears to be a correlation between the healing index and the retention of amino acid sulfur in excess of that expected on the basis of nitrogen retention.

Effects of immobilization upon various metabolic and physiologic functions of normal men

A study of the effects of immobilization upon various metabolic and physiologic functions of four normal, healthy, young men was carried out on a metabolism ward during control (five to seven weeks), immobilization (six to seven weeks) and recovery (four to six weeks) periods. Throughout the study, dietary intake was kept constant. During the immobilization period the subjects were placed in bi-valved plaster casts extending from the umbilicus to the toes. 1. 1. Nitrogen excretion began to increase on the fifth to sixth day of immobilization and reached its peak during the first half of the second week. Total nitrogen losses ranged from 29.8 to 83.6 Gm., and averaged 53.6 Gm. 2. 2. Both urinary and fecal calcium excretion increased during immobilization, maximum excretion being reached by the fourth to fifth week. Total calcium losses ranged from 9 to 23.9 Cm. The calcium content of the urine was doubled during immobilization. The absence of appreciable increase in urine volume, the slight rise in urinary pH and the failure of urinary citric acid to rise parallel with the increase in calcium would all favor the precipitation of calcium phosphate in the urinary tract. A slight elevation in serum calcium levels occurred at the end of the immobilization period. 3. 3. During immobilization there was an increase in the excretion of phosphorus, total sulfur, sodium and potassium. Total sulfur was excreted in the urine in close correlation from week to week with urinary nitrogen in the ratio in which these elements exist in muscle protoplasm. The changes in phosphorus excretion showed moderately good correlation with the changes in nitrogen and calcium excretion. 4. 4. During recovery there was retention of nitrogen, calcium, phosphorus, sulfur and potassium. The recovery or return to control levels of metabolic functions was slow, retention of nitrogen and phosphorus continuing for six weeks. Re-stabilization of calcium metabolism appeared to require more than six weeks. 5. 5. Although creatine and creatinine excretion remained fairly constant, there was a definite lowering of creatine tolerance during immobilization. This impairment in creatine metabolism was accompanied by a significant decrease in muscle mass and muscle strength in the immobilized limbs. 6. 6. In only one subject was there a significant lowering of 17-ketosteroid excretion during immobilization; this subject also experienced the largest nitrogen losses. 7. 7. The decline in basal metabolic rate during immobilization averaged 6.9 per cent among the four subjects. 8. 8. Immobilization brought about a deterioration in the mechanisms essential for adequate circulation in the erect position as indicated by an increased tendency to faint in tilt table tests. Experiments indicated that the legs were the principal site of changes responsible for this deterioration and suggested that increased venous engorgement, increased extravascular fluid, capillary fragility and impaired venous or muscle tone play a r&e. 9. 9. Other circulaotry changes brought about by immobilization were a decline in total blood volume averaging 5.4 per cent, marked decreases in exercise tolerance as measured by Master and Schneider tests and an increase in the resting pulse rate of 3.8 beats per minute during immobilization, followed by an additional increase of 4.7 beats per minute during the first three weeks of recovery. 10. 10. The recovery or return to control levels of most physiologic functions required three to four weeks; exercise tolerance and leg girth required four to six weeks and the reclining pulse rate more than six weeks. 11. 11. Changes in body weight during immobilization were small, probably as a result of the simultaneous loss of muscle protoplasm and storage of fat or carbohydrate. 12. 12. There were no significant changes due to immobilization in blood coagulation studies, blood circulation time, heart size, electrocardiograms, resting arterial blood pressure, hematocrits, blood counts, vital capacity, maximum ventilation capacity or breath-holding.

Adherence and Retention of Sulfur on Citrus Foliage

Adherence and Retention of Sulfur on Citrus Foliage

NITROGEN AND SULPHUR METABOLISM IN BRIGHT'S DISEASE

It has previously been noted by Peters and others1that patients exhibiting the nephrosis syndrome retain a large proportion of the intake of nitrogen without an increase in the nonprotein nitrogen in the blood, and that even when crystalline urea is added to the diet, it is retained. Peters and Van Slyke2thought that the retention of nitrogen serves to make up the loss of body protein chiefly in the form of albumin excreted in the urine. If this is true, it accounts in part for the retention of sulphur noted formerly.3So far as I have been able to ascertain, no studies have been made on the relation between the excretion of nitrogen and that of sulphur in this condition when crystalline urea has been added to a diet already high in protein. I shall report metabolism studies on a patient, whose case history was included