Dimethyl sulfide (DMS) or methylthiomethane is anorganosulfur compound with the formula(CH3)2S. It is the simplestthioether and has a characteristic disagreeable odor. It is aflammable liquid that boils at 37 °C (99 °F). It is a component of the smell produced from cooking of certain vegetables (notablymaize,cabbage, andbeetroot) andseafoods. It is also an indication ofbacterial contamination inmalt production andbrewing. It is a breakdown product ofdimethylsulfoniopropionate (DMSP), and is also produced by the bacterial metabolism ofmethanethiol.
DMS originates primarily from DMSP, a major secondary metabolite in somemarine algae.[5] DMS is the most abundant biological sulfur compound emitted to theatmosphere.[6][7] Emission occurs over theoceans byphytoplankton.
DMS is also produced naturally by bacterial transformation ofdimethyl sulfoxide (DMSO).[8]
Marine phytoplankton also produce dimethyl sulfide,[9] and DMS is also produced by bacterial cleavage of extracellular DMSP.[10] This may be an adaptive trait, as the algae can use the resulting clouds to disperse themselves around the world.[11] DMS has been characterized as the "smell of the sea",[12] though it would be more accurate to say that DMS is a component of the smell of the sea, others being chemical derivatives of DMS, such as oxides, and yet others being algalpheromones such asdictyopterenes.[13]
Dimethyl sulfide has been detected in comets, which indicates non-living sources are available.[15] For comet 67P/Churyumov-Gerasimenko, the European Space Agency sampled the cloud of dust and gas shed from the comet.[16][17][18]
Dimethyl sulfide has a characteristic odor commonly described ascabbage-like. It becomes highly disagreeable at even quite low concentrations. Some reports claim that DMS has a low olfactory threshold that varies from 0.02 to 0.1 ppm[clarification needed] between persons, but it has been suggested that the odor attributed to dimethyl sulfide may in fact be due to disulfides, polysulfides and thiol impurities, since the odor of dimethyl sulfide is much less disagreeable after it is freshly washed with saturated aqueous mercuric chloride.[20] Dimethyl sulfide is also available as a food additive to impart a savory flavor; in such use, its concentration is low.Beetroot,[21]asparagus,[22]cabbage,maize andseafoods produce dimethyl sulfide when cooked.
Dimethyl sulfide is also produced by marineplanktonic microorganisms such as thecoccolithophores. It contributes to the characteristic odor ofsea air. In theVictorian era, before DMS was discovered, the origin of sea air's 'bracing' aroma was misattributed toozone.[23]
Dimethyl sulfide is the main volatile product various oftruffles. It is the compound that animals trained to uncover the fungus (such aspigs anddetection dogs) sniff out when searching for them.[24]
Oxidation of dimethyl sulfide gives the solventdimethyl sulfoxide. Further oxidation affordsdimethyl sulfone. Dimethyl sulfide is used in the workup of theozonolysis ofalkenes, where it reduces the intermediate trioxolane.
TheSwern oxidation produces dimethyl sulfide by reduction of dimethylsulfoxide.[25]
Dimethyl sulfide is normally present at very low levels in healthy people, namely less than 7 nM in blood, less than 3 nM in urine and 0.13 to 0.65 nM on expired breath.[36][37]
^Kappler, U.; Schäfer, H. (2014). "Chapter 11. Transformations of Dimethylsulfide". In Kroneck, P. M. H.; Sosa Torres, M. E. (eds.).The Metal-Driven Biogeochemistry of Gaseous Compounds in the Environment. Metal Ions in Life Sciences. Vol. 14. Springer. pp. 279–313.doi:10.1007/978-94-017-9269-1_11.ISBN978-94-017-9268-4.PMID25416398.
^Glindemann, D.; Novak, J.; Witherspoon, J. (2006). "Dimethyl Sulfoxide (DMSO) Waste Residues and Municipal Waste Water Odor by Dimethyl Sulfide (DMS): the North-East WPCP Plant of Philadelphia".Environmental Science and Technology.40 (1):202–207.Bibcode:2006EnST...40..202G.doi:10.1021/es051312a.PMID16433352.
^Itoh, T.; Inoue, H.; Emoto, S. (2000). "Synthesis of Dictyopterene A: Optically Active Tributylstannylcyclopropane as a Chiral Synthon".Bulletin of the Chemical Society of Japan.73 (2):409–416.doi:10.1246/bcsj.73.409.ISSN1348-0634.
^Morton, T. H. (2000). "Archiving Odors". In Bhushan, N.; Rosenfeld, S. (eds.).Of Molecules and Mind. Oxford: Oxford University Press. pp. 205–216.
^Parliment, T. H.; Kolor, M. G.; Maing, I. Y. (1977). "Identification of the Major Volatile Components of Cooked Beets".Journal of Food Science.42 (6):1592–1593.doi:10.1111/j.1365-2621.1977.tb08434.x.
^U., Detlef; Hoberg, E.; Bittner, T.; Engewald, W.; Meilchen, K. (2001). "Contribution of volatile compounds to the flavor of cooked asparagus".European Food Research and Technology.213 (3):200–204.doi:10.1007/s002170100349.S2CID95248775.
^Talou, T.; G aset, A.; Delmas, M.; Kulifaj, M.; Montant, C. (1990). "Dimethyl sulphide: the secret for black truffle hunting by animals?".Mycological Research.94 (2):277–278.doi:10.1016/s0953-7562(09)80630-8.ISSN0953-7562.
^Reich, Hans J. (2013). "Role of Organolithium Aggregates and Mixed Aggregates in Organolithium Mechanisms".Chemical Reviews.113 (9):7130–7178.doi:10.1021/cr400187u.PMID23941648.
^"DIMETHYL SULFIDE".OSHA Occupational Chemical Database. Occupational Safety and Health Administration, U.S. Department of Labor. 28 December 2020. Retrieved14 January 2025.
^ab"DIMETHYLSULPHIDE".International Chemical Safety Cards. International Labour Organization. March 1999. ICSC 0878. Retrieved14 January 2025.
^Tangerman, A. (15 October 2009). "Measurement and biological significance of the volatile sulfur compounds hydrogen sulfide, methanethiol and dimethyl sulfide in various biological matrices".Journal of Chromatography B.877 (28):3366–3377.doi:10.1016/j.jchromb.2009.05.026.PMID19505855.
^Tangerman, A.; Winkel, E. G. (September 2007). "Intra- and extra-oral halitosis: finding of a new form of extra-oral blood-borne halitosis caused by dimethyl sulphide".J. Clin. Periodontol.34 (9):748–755.doi:10.1111/j.1600-051X.2007.01116.x.PMID17716310.
^Tangerman, A.; Winkel, E. G. (March 2008). "The portable gas chromatograph OralChroma: a method of choice to detect oral and extra-oral halitosis".Journal of Breath Research.2 (1) 017010.doi:10.1088/1752-7155/2/1/017010.PMID21386154.S2CID572545.
