• BMB Reports
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• v.42 no.9
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• pp.580-585
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• 2009

Dimethyl sulfoxide (DMSO) is widely used in chemistry and biology as a solvent and as a cryoprotectant. It is also used as a pharmaceutical agent for the treatment of interstitial cystitis and rheumatoid arthritis. Previous reports described DMSO as being reduced by methionine-S-sulfoxide reductase (MsrA). However, little is known about the DMSO reduction capability of methionine-R-sulfoxide reductase (MsrB) or its effect on the catalysis of methionine sulfoxide reduction. We show that mammalian MsrB2 and MsrB3 were unable to reduce DMSO. This compound inhibited MsrB2 activity but did not inhibit MsrB3 activity. We further determined that DMSO functions as an inhibitor of MsrA and MsrB2 in the reduction of methionine sulfoxides via different inhibition mechanisms. DMSO competitively inhibited MsrA activity but acted as a non-competitive inhibitor of MsrB2 activity. Our study also demonstrated that DMSO inhibits in vivo methionine sulfoxide reduction in yeast and mammalian cells.

• BMB Reports
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• v.43 no.9
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• pp.622-628
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• 2010

Dimethyl sulfoxide (DMSO) can be reduced to dimethyl sulfide by MsrA, which stereospecifically catalyzes the reduction of methionine-S-sulfoxide to methionine. Our previous study showed that DMSO can competitively inhibit methionine sulfoxide reduction ability of yeast and mammalian MsrA in both in vitro and in vivo, and also act as a non-competitive inhibitor for mammalian MsrB2, specific for the reduction of methionine-R-sulfoxide, with lower inhibition effects. The present study investigated the effects of DMSO on the physiological antioxidant functions of methionine sulfoxide reductases. DMSO elevated hydrogen peroxide-mediated Saccharomyces cerevisiae cell death, whereas it protected human SK-Hep1 cells against oxidative stress. DMSO reduced the protein-carbonyl content in yeast cells in normal conditions, but markedly increased protein-carbonyl accumulation under oxidative stress. Using Msr deletion mutant yeast cells, we demonstrated the DMSO's selective inhibition of the antioxidant function of MsrA in S. cerevisiae, resulting in an increase in oxidative stress-induced cytotoxicity.

• Archives of Pharmacal Research
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• v.20 no.1
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• pp.91-92
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• 1997

In the course of continous work on tubers of Gastrodia elata, a new constituent, 4, 4$^{I}$-dihydroxybenzyl sulfoxide was isolated from the ethyl acetate soluble fraction prepared from the methanol extract. The structure of the compound was identified from the elemental analytical and spectroscopic data in comparison with those of non-substituted benzyl sulfoxide.e.

• Journal of Yeungnam Medical Science
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• v.4 no.1
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• pp.17-23
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• 1987

New born rat heart cells were dissociated using trypsin and/or collegenase to elucidate the dissociation efficiency of these two enzymes. And the effect of dimethyl sulfoxide during and immediately after cell dissociation was also investigated to clarify the so-called protective activity of dimethyl sulfoxide on cell performance. The results can be summarized as follows. 1. Cold trypsin 18 hours pretreatment followed by warm collagenase treatment resulted best cell viability and cell yield. 2. Single, warm trypsin treatment gave the poorest result. 3. Dimethyl sulfoxide did not seem to play any protective role during or immediately after rat heart cell dissociation. It had very damaging effect on rat heart cells.

• Bulletin of the Korean Chemical Society
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• v.25 no.9
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• pp.1379-1384
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• 2004

Rearrangements of 1,3-oxathiolane sulfoxides 8 and 9 in the presence of base are described from a mechanistic viewpoint of sigmatropic and elimination reactions. In the presence of triethylamine the (Z)-sulfoxide 8 gave the corresponding thiolsulfinate 10 by way of dimerization of the sulfenic acid intermediate 2 at room temperature while the (E)-sulfoxide 9 was recovered even after refluxing in ethyl acetate by the reversal of the [2,3]-sigmatropic rearrangement of the sulfenic acid 4. Triethylamine promoted the developing charge separation in the transition state of the sigmatropic rearrangement of the (Z)-sulfoxide 8 to facilitate the ring opening to the sulfenic acid 2. The reason for more facile ring opening of the (Z)-sulfoxide 8 in comparison with the corresponding (E)-sulfoxide 9 is attributable to the differences in the reactivity of the hydrogen adjacent to the carbonyl group. Triethylamine was not strong base to deprotonate the carbonyl-activated methylene hydrogen of the (E)-sulfoxide 9 but enough to catalyze the sigmatropic process of the sulfoxides. The sulfenic acid 2 dimerized to the thiolsulfinate 10 while the sulfenic acid 4 proceeded the sigmatropic ring closure. In the presence of strong base such as potassium hydroxide, the elimination reaction was predominant over the sigmatropic rearrangement. In this reaction condition, both sulfoxides 8a and 9a gave a mixture of the disulfide 12, the isomeric disulfide 14, and the sulfinic acid 13. Under the strong alkaline condition an elimination of activated hydrogen from the carbon adjacent to the carbonyl group to furnish the sulfenic acid 2a and the isomeric sulfenic acid 18. The formation of the transient intermediate in the reaction was proven by isolation of the isomeric disulfide 14. The reactive entity was regarded as the sulfenic acid rather than sulfenate anion under these reaction conditions.

• Korean Journal of Soil Science and Fertilizer
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• v.24 no.2
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• pp.116-123
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• 1991

Two solution to soil ratios, 2 : 1 and 5 : 1 were tested to determine the appropriate ratio in the sorption measurement off. sulfoxide for Wahiawa soil samples, 0-20 cm, 40-60 cm and 100-120 cm. and Salinas soil samples, 0-15cm and 115-130cm. One ${\mu}$ mol/L f.sulfoxide was used as an initial equilibration concentration. Sorption of f.sulfoxide at 5 : 1 ratio showed appropriate mixing, while sorption at 2 : 1 ratio indicated insufficient mixing during the various batch equilibration times (4, 12, 24 and 48 hours). For most samples the degree of sorption was about 20-50%, which falls in the desired range (20-80%) at the 5 : 1 ratio. An exception was with the low-sorptive Wahiawa subsoil in which the ranges were below 20%. Thus the 5 : 1 ratio can be used for f.sulfoxide sorption measurement. Four equilibration times (4, 12, 24 and 48 hours) and four concentrations(0.1, 1.0, 5.0 and $10{\mu}mol/L$) were used to determine the appropriate equilibration time for Wahiawa and Salinas soils. Sorption increased over all equilibration times, indicating no complete equilibrium within 48 hours. Apparent equilibrium was reached in 4 hours, and sorption increased slowly until 24 hours and faster thereafter, except for the Wahiawa soil, 100-120 cm. The recommended equilibration time is 24 hours, since it may eliminate the insufficient sorption and yet avoid undesirable transformation.

• Journal of the Korean Chemical Society
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• v.33 no.5
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• pp.516-521
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• 1989

Reaction between the $N_2O_2-type$ tetradentate ligand, ethylenediamine-N,N'-di-S-${\alpha}$-isobutylacetic acid (SS-emiba) and $RhCl_3{\cdot}3H_2O$ has yielded ${\Delta}-s-cis-\;and\;{\wedge}-uns-cis-[Rh(SS-eniba)Cl_2]-$. ${\Delta}-s-cis-[Rh(SS-eniba)Cl_2]^-$ has been utilized to react with S-methyl-L-cystcine(Smc) to give ${\Delta}-s-cis-[Rh(SS-eniba(Smc)]^+$. The oxidation of ${\Delta}-s-cis-[Rh(SS-eniba(Smc)]^+$ using $H_2O_2$ has produced ${\Delta}-s-cis-[Rh(SS-eniba)(Smc-o)]^+$, in which the coordinated sulfur has been converted into the sulfoxide group. In a separate series of experiments the S-methyl-L-cysteine is oxidized by $H_2O_2$ to give S-methyl-L-cysteine sulfoxide, which is then coordinated to ${\Delta}-s-cis-[Rh(SS-eniba)Cl2]^-$ to make the standard complet of ${\Delta}-s-cis-[Rh(SS-eniba)(Sme-o)]+$ for comparison with the complex obtained from the oxidation of ${\Delta}-s-cis-[Rh(SS-eniba)(Smc)]^+\;by\;H_2O_2.$

• Applied Biological Chemistry
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• v.26 no.2
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• pp.97-103
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• 1983

To get further information on the behavior of phorate(0,0-diethyl S-ethylthiomethyl phosphorodithioate) in soil under the subtropical conditions, a field experiment has been conducted. Phorate granule (10%) was applied to silt loam soil at the rate of 40kg a.i./ha and incorporated to 10cm soil depth. Residues of phorate and its metabolites in soil were determined with GLC and confirmed qualitatively with TLC. Phorate was rapidly oxidized to its sulfoxide and sulfone. Therefore, main metabolic pathway of phorate in soil was the oxidation of phorate to phorate sulfoxide and sulfone. Phorate sulfoxide and sulfone were relatively more persistent than phorate itself. Phoratoxon was detected at low level only up to 30 days after treatment and its sulfoxide and sulfone were not detected during the whole experimental period. Toluene-acetonitrile-nitromethane(40 : 30 : 30, v/v/v) solvent system separated satisfactorily phorate and its five metabolites. Most of the residues was found in the initial incorporation depth $(0{\sim}10cm)$. Consequently, insecticides showed a little downward movement.

• Journal of Sericultural and Entomological Science
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• v.38 no.2
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• pp.124-129
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• 1996

Oral application of dimethyl sulfoxide in different concentration (1, 3 and 5 percent) to silkworm, Bomyx mori at the fourth and the fifth instar has significantly increased the commercial characters such as larval and silkgland weights, female and male cocoon weights, their shell weights and egg production. However, larval duration, cocooning and hatching percentages did not showed any significant change, as compared with that of the corresponding parameters of the carrier control. Similarly the glycogen and protein contents of the fat body and trehalose and protein contents of the haemolymph were significantly increased in 1 and 3 percent, whereas the increase of them in 5 percent concentration did not take place significantly, except haemolymph trehalose where it was found to be significant, as compared with that of carrier control.

• Journal of the Korean Chemical Society
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• v.26 no.5
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• pp.340-348
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• 1982

The presence of 10 mole percent triphenyl borate accelerated dramatically the rate of reduction of structurally different sulfoxides with borane in tetrahydrofuran at room temperature, compared to the slow reduction with borane itself. Tetramethylene sulfoxide underwent complete reduction in 5 min and diethyl sulfoxide, dibenzyl sulfoxide and benzylphenyl sulfoxide were reduced quantitatively within 1h, whereas the reduction of diphenyl sulfoxide was rather slow, giving diphenyl sulfide in 90% yield in 24h. Boron trifluoride etherate and triethyl borate were less effective than triphenyl borate. A possible mechanism is presented.