Benzothiazole degradation

Haroune N, B Combourieu, P Besse, M Sancelme, T Reemtsma, A Kloepfer, A Diab, JS Knapp, S Baumberg, A-M Delort (2002) Benzothiazole degradation by Rhodococcus pyridinovorans strain PA evidence of a catechol 1,2-dioxygenase activity. Appl Environ Microbiol 68 6114-6120. 

Proceedings of European Symposium on Environmental Biotechnology, ESEB 2004, Oostende, Belgium, Apr. 25-28, 2004, ed. W. Verstraete, A.A. Balkema, Lisse, Netherlands, 2004 R 249 N. Haroune, B. Combourieu, P. Besse, M. Sancelme and A.M. Delort, Liquid and Solid State NMR Study of Benzothiazole Degradation by Rhodococcus Isolates , p. 705... 

By reduction in the degree of polymerisation. To produce processable rubbers the original polymers are masticated with substances such as benzothiazole disulphide and tetramethylthiuram disulphide. The more severe degradation techniques to produce liquid polysulphides are mentioned below. 

Thiocyanomethylthio)benzthiazole initially forms 2-thiobenzthiazole, which is transient and then rapidly degrades photochemically to benzothiazole and 2-hydroxybenzo-thiazole (Brownlee et al. 1992). 

The degradation of benzothiazole was examined in two strains of Rhodococcus. The structure of the metabolite as 2,6-dihydroxybenzothiazole was determined by long-range... 

Benzothiophene is isoelectronic with naphthalene, dibenzothiophene with anthracene, and benzothiazole with quinoline, and this is reflected in their aerobic degradation that is initiated by dioxygenation. The diversity of pathways for the degradation of dibenzothiophene is illustrated by the following examples ... 

Sulfur Compounds of Beef Flavor. Methional, which results from the degradation of methionine, is an important contributor to flavor in meat. Thiolanes, formed during the cooking of beef, have peculiar oniony flavors that also augment the quality of the meaty flavor. Thiophenes and thiofurans are also important to meaty flavors. Sulfides, such as methyl sulfide, are oxidized to methyl sulfoxide and methyl sulfone. Condensation reactions of Maillard browning products also result in thiazoles such as benzothiazole, an important component of meat flavor. 

Benzothiazoles from vulcanization of rubber tires are found so enriched in some situations that they are used as a marker for street run-off water. Thiocya-natomethylthiobenzothiazole used as a fungicide in wood protection and antifouling paints may degrade into benzothiazoles and methylthiobenzothiazole is used in vulcanization processes, so these materials find their way into rivers and ultimately estuaries. Bester et al. (1997) determined the presence of benzothiazole and methylthiobenzothiazole in estuarine and marine waters. Their concentrations range from 0.04 ngL to 1.37 ngL . Methylthiobenzothiazole and benzothiazole vary from 0.25 ng L to 2.7 ngL in the North Sea, while 55 ngL methylthiobenzothiazole was found in the Elbe River. 

Degradation of benzothiazoles by Rhodococcus strains. In an interesting environmental application of long-range 2D results at natural abundance, Delort and co-... 

It is well-known that benzothiazoles are used as accelerators in the vulcanization process <84CHEC-l(6)330>. Because of the toxicity of the benzothiazole-containing by-products produced in rubber manufacture, it is of interest in the isolation of bacteria which degrade those by-products <93MI 306-12>. The one mainly responsible for the toxicity of rubber chemical waste water is 2-thiob-enzothiazole <93MI 306-l3>. 

Benzothiazole 3-oxides. Benzothiazole 3-oxide (64), unlike its 2-methyl homologue (63), is not obtainable by direct oxidation with permaleic acid. It has now been prepared from (63) by a seven-stage degradation. 

During the concentration and drying of milk, reactions that are similar to those described for heat-treated milk (cf. 10.1.3.5 and 10.3.1) occur, but to a greater extent. Thwefore, like the aroma of UHT milk (cf. 10.3.1 and Table 10.38), the aroma of condensed milk is also caused by Maillard reaction products. The stale flavor that appears when condensed milk is stored for longer periods is due especially to the presence of the degradation product of tryptophan, o-aminoacetophenone, which is aroma active in concentrations >lpg/kg. A mbbery aroma defect results from higher concentrations of benzothiazole. 

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