Organic Sulfur Forms Research Articles

The inorganic sulfate transport system of Penicillium chrysogenum

Inorganic sulfate enters the mycelium of Penicillium chrysogenum against an apparent concentration gradient by a temperature-, energy-, pH-, and concentration-dependent transport system that is regulated by the degree of sulfur-deficiency of the mycelium. Sulfate transport can take place in the absence of sulfate reduction and organic sulfur formation. The rapid conversion of sulfate to organic sulfur in the absence of N-ethylmaleimide suggests that the newly-transported 35SO 4 −− does not completely equilibrate with the pre-existing sulfate pool. Only about half of the transported sulfate could be removed by exhaustive washing or exchanged with unlabeled extracellular sulfate. The kinetics of transport and exchange also suggest the presence of two distinct intracellular sulfate pools. Inorganic thiosulfate, a suggested intermediate and overflow product of fungal sulfate reduction is an extracellular inhibitor of sulfate transport. Sulfite is an extracellular inhibitor at pH 5 but not at pH 6.5. Methionine and cysteine are not extracellular inhibitors of sulfate transport, but are rapidly converted intracellularly to a feedback inhibitor. The V max and apparent K m of the sulfate transport system (in the presence of NEM) are 0.5 – 1.0 μ mole/gmminute and 3–7 × 10 −5 m, respectively, at pH 6.5. Inorganic selenate inhibits sulfate transport and is taken up by the mycelium via the sulfate transport system. In the absence of net transport, sulfate will still adsorb to the mycelial surface very rapidly (or penetrate into a free space) by a DNP- and temperature-insensitive process.

SULPHUR FRACTIONS OF SELECTED ALBERTA SOIL PROFILES OF THE CHERNOZEMIC AND PODZOLIC ORDERS

Total sulphur, carbon-bonded sulphur, HI-reducible sulphur, easily soluble sulphate, adsorbed sulphate, and sulphate associated with calcium carbonate were determined on seven Grey Wooded profiles and eight Chernozemic profiles, the latter including soils from the Brown, Dark Brown, Thin Black, and Black soil zones of Alberta.A clear dichotomy was observed between the Chernozemic and Grey Wooded (Podzolic) profiles. Organic forms of sulphur predominated in all surface and B horizons, although inorganic sulphate reached high levels in C horizons of some Chernozemic profiles. HI-reducible sulphur accounted for 63% and 71% of the total sulphur of Chernozemic Ah and Bm horizons, but only 33% and 48% of the total sulphur of Grey Wooded L-H and Bt horizons. N:HI-reducible sulphur ratios were much wider in the surface and B horizons of the Grey Wooded profiles than in the Chernozems. Carbon-bonded sulphur decreased with depth in all profiles, representing 17% and 9% of the total sulphur in the Chernozemic Ah and Bm, and 26% and 15% in the Grey Wooded L-H and Bt respectively. Sulphated polysaccharides were isolated from all surface horizons, but in no case accounted for more than 2% of the total sulphur. An inert sulphur fraction, resistant to strong oxidizing and reducing agents, was detected in residues of four samples subjected to exhaustive extraction with hot acid and alkali. This fraction accounted for 2–44% of the total sulphur, the highest value being observed in a Grey Wooded L-H sample.

Chemical Studies on the Sulfur of Japanese Coals(II).

n order to investigate chemical forms of organic sulfur occupying more than 80% of the total coal sulfur (mainly, bituminous coal for metallurgical use), estimations of various organic radicals containing sulfur were attempted to be made about the solvent extract of coal.And the following results were obtained.(1) In the exam-ination of the solvent for extraction of coal, tetrahydrofuran and dimethylformamide, which have been so far little used for extraction of coal, and benzene were used because of their various advantages.(2) The methods of estimations of various radicals containing sulfur were established after examination by using pure organic sulfur compounds.Then the following values of contents for various radicals were obtained concerning extracts of Miike coal: thiol (—SH) 3-9%, disulffide (—S—S—) 6-13%, sulfide which does not combine directly to the aromatic ring (—S—) and sulfidecombining in the saturated heterocyclic ring28-37%, sulfide combining directly to the aromatic ringand sulfide combining in the the hetero-cyclic ring7-19%, and undetermined—30%.(3) It is conceivable that the organic sulfur in coal extract which can be reduced by Raney nickel (corres-ponding to the total of each form determined by the above method) has greater chemical activity than the other ones in coal.And the content of this organic sulfur against the total organic sulfur in coal showed the maximum value at the rank of83-84% carbon. Therefore, it was inferred that the reactivity of organic sulfur in coal has the largest value for coal of 83-84%carbon.

Chemical Studies on the Sulfur of Japanese Coals(I)

n order to investigate chemical forms of organic sulfur occupying more than 80% of the total coal sulfur (mainly, bituminous coal for metallurgical use), estimations of various organic radicals containing sulfur were attempted to be made about the solvent extract of coal.And the following results were obtained.(1) In the exam-ination of the solvent for extraction of coal, tetrahydrofuran and dimethylformamide, which have been so far little used for extraction of coal, and benzene were used because of their various advantages.(2) The methods of estimations of various radicals containing sulfur were established after examination by using pure organic sulfur compounds.Then the following values of contents for various radicals were obtained concerning extracts of Miike coal: thiol (—SH) 3-9%, disulffide (—S—S—) 6-13%, sulfide which does not combine directly to the aromatic ring (—S—) and sulfidecombining in the saturated heterocyclic ring28-37%, sulfide combining directly to the aromatic ringand sulfide combining in the the hetero-cyclic ring7-19%, and undetermined—30%.(3) It is conceivable that the organic sulfur in coal extract which can be reduced by Raney nickel (corres-ponding to the total of each form determined by the above method) has greater chemical activity than the other ones in coal.And the content of this organic sulfur against the total organic sulfur in coal showed the maximum value at the rank of83-84% carbon. Therefore, it was inferred that the reactivity of organic sulfur in coal has the largest value for coal of 83-84%carbon.

Distribution of Sulfur in oil Shale

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDistribution of Sulfur in oil ShaleE. P. Harding and William ThordarsonCite this: Ind. Eng. Chem. 1926, 18, 7, 731–733Publication Date (Print):July 1, 1926Publication History Published online1 May 2002Published inissue 1 July 1926https://doi.org/10.1021/ie50199a020RIGHTS & PERMISSIONSArticle Views36Altmetric-Citations2LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (390 KB) Get e-Alerts