• 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.

• Journal of dental hygiene science
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• v.11 no.3
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• pp.213-220
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• 2011

To examine the relationship between occurrence of oral malodor and smoking, drinking, oral health behavior characteristics. A total of 144 adults were measuring the malodor by use of Oral Chroma volatile sulfur compounds. Data were analyzed with t-test, one-way of variance and multiple regression analysis using SPSS 12.0. hydrogen sulfide($H_2S$) was indicated to be so higher concentration in the group of carrying out scaling sometimes than the regularly group(p<0.01). methyl mercaptan($CH_3SH$) was indicated to be higher concentration in previous smoker than non-smoker and smoker(p<0.05), smoking for over 20 years was higher than the under 20 years group(p<0.05). The group of drinking over 5 times a week was indicated to have higher concentration than the under once-twice a week group(p<0.01). The group of not toothbrushing before going to sleep had higher concentration than the group of toothbrushing before going to sleep(p<0.05). The group of scaling sometimes was indicated to have higher concentration than the group of scaling regularly(p<0.05). dimethyl sulfide($(CH_3)_2S$) was indicated to be higher concentration in the group with over 2 bottles of Soju than in the group with under 1 bottles of Soju(p<0.01). The regular scaling will need to be carried out in the preventive dimension for managing oral malodor. The guidance on non-smoking and moderation in drink will need to be surely included.

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.123-128
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• 2004

Effects of jeotkal (salted-fermented seafoods) addition on acid production, growth of lactic acid bacteria, sensory properties, and volatile odor components of kimchi were investigated. Changes in pH and acidity of kimchi added with myulchi-aekjeot, kanari-aekjeot, and aekche-Jukjeot were similar to, whereas those of saeu-jeot sample on 0, 2, and 4 days of ripening were slightly different, those of control sample. Changes in pH and acidity of jogae-jeot sample during whole ripening period were markedly different from those of other samples. Numbers of lactic acid bacteria of all samples on 0 and 4 days were $1.8-2.6{\times}10^{5}\;and\;1.0-2.5{\times}10^{9}\;CFU/mL$, respectively. Overall acceptability and taste of kimchi added with jeotkal except jogae-jeot were higher than those of control sample, with saeu-jeot-added kimchi showing the highest scores. Eight volatile odor components were identified in 6-day-ripened kimchi samples, and those of saeu-jeot sample were slightly higher than those of other samples. Diallyl sulfide and methyl propyl disulfide were produced in 6-day-ripened samples. Ethanol, methyl allyl sulfide, and dimethyl disulfide concentrations increased, whereas that of allyl mercaptan decreased in 6-day-ripened samples compared to unripened ones.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.12
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• pp.1637-1642
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• 2007

The objectives of this study were to compare the aroma characteristics and antioxidant activity of raw and heated garlic ($130^{\circ}C$, 2 hr) from different cultivation areas (Danyang, Seosan, Uiseong Namhae, Namdo, Daeseo and China). The volatile compounds were extracted by simultaneous steam distillation extraction and identified with gas chromatography/mass spectrometer. The major volatile compounds of raw garlic were sulfur compounds such as diallyl disulfide, methyl-2-propenyl trisulfide, di-2-propenyl trisulfide etc. After heating, the major volatile compounds were allyl mercaptan, methyl pyrazine, 2,2-dimethyl-1,3-dithiane, 2-propenyl propyl disulfide, allyl methyl sulfide, allyl alcohol, and allyl sulfide etc. The DPPH radical scavenging activity (EDA, %) of volatile compounds from raw garlic and heated garlic was increased in a dose-dependent manner. The antioxidant activities (EDA, %) of volatile compounds from raw garlic cultivated in Danyang, Namhae and China were 20.07, 34.62, and 9.71% respectively. After heating, these values were increased to 79.90, 93.59, and 77.26% respectively. Results showed that heat treatment significantly enhanced the antioxidant activities (EDA, %) of the garlic.

• Applied Biological Chemistry
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• v.44 no.1
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• pp.12-19
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• 2001

The major volatiles from Allium species were found to be sulfide compounds and the ratio of sulfide to volatiles was 66.1% in garlic, 66.1% in scallion, 62.3% in green onion, 39.2% in onion, and 4.2% in chive. Trace of cyclooctasulfur was found to be present among the volatiles. The most oviposition of 17.2% occurred at diallyl sulfide and the least of 0.8% at acetylthiophene whereas the most oviposition of 43.3% occurred at ethyl alcohol if concentration was 100%. Among the organic solvents used for dilution, ethyl alcohol received the highest 52.5% of oviposition and ether the lowest of 5.9%. Furfuryl mercaptan which is also one of the volatiles, received 46.9% of oviposition. For oviposition site, D. antiqua preferred sulfides at near 1%, ethyl alcohol at high, and other volatiles at various concentrations. At 100% concentration, most volatiles except dimethyl disulfide and ethyl alcohol received less oviposition than the control which was watered sand with no volatiles added.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1549-1556
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• 1999

This study was conducted to investigate the effects of pre-treated sub-ingredients and deodorization materials on the smell intensity of Kimchi during fermentation.Among the various sub-ingredients of Kimchi, garlic, ginger and green onion have comparatively strong smell. The smell intensities of the sub-ingredients, which were pre-treated with various patented methods were examined using the sensory evaluation method and AromaScan. The results showed that the good methods to reduce the smell of sub-ingredients were hot air drying and soaking with heating treatment. The pH, titratable acidity and the number of microorganism of Kimchi prepared with pre-treated sub-ingredients were not different among samples during fermentation. The smell intensity of the Kimchi with pre-treated sub-ingredients was weaker than that of control until ten fermentation days, but the smell intensity after 10 days of fermentation was not different among samples. The addition of ${\alpha}-cyclodextrin\;and\;{\beta}-cyclodextrin$, which are known to have deodorization effect, at a level of 0.1% respectively, to Kimchi resulted in no difference in the pH, titratable acidity and smell intensity during fermentation at $10^{\circ}C$ compared to those of control Kimchi. However, the addition of deodorizer reduced sulfide classes such as methyl allyl sulfide, dimethyl disulfide, allyl sulfide, methyl propyl disulfide up to 50%.

• The Korean Journal of Food And Nutrition
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• v.13 no.5
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• pp.483-489
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• 2000

Wild Chopi leaves were harvested near Chounghwa Mt. Sangju city in Kyungpook province. Chopi leaves were dried naturally and crushed with and without blanching. From mechanical analysis(GC). fifty five peaks were identified as volatile materials in no blanching leaf. Among the fifty five peaks, twenty three peaks were identified as hydrocarbones(dodecane, sabinene, myrcene etc.), ten peaks as alcohols (isobutylalcohol. cis-pentenol, 1-pentenol, 1-penten-3-ol etc.), seven peaks as aldehydes (3-methylbua-tanal, hexanal, 2,6-dimethyl hept-5-al etc.), four peaks as ketones(3-hydroxy-2-butanone, 2-nonanone, 2-undecanone, 2-tridecanone) and six peaks as esters ( cis-3-hexenyl acetate, linalyl acetate. citronellyl acetate, nervy acetate etc.). Other peaks were founded as 3-cyano-2,5-dimethylpyrazine, dimethyl sulfide, chloroform, 1,8 cineole. Thirty five peaks were identified as volatile materials in blanching leaf. Twenty peaks were identified as hydrocarbones(1,1-oxybis-ethane, $\alpha$-pinene, camphene. myrcene, $\beta$-phellan-drene, $\beta$-caryophyllene etc.), as alcohol(L-linalool, (-)-isopulgerol, $\alpha$-terpineol. citronellol etc.), as aldehydes(nonanal, citronellal), as ketones(2-undecanone, 2-tridecanone etc.) and as esteres(citronellyl acetate. cis-3-hexenyl acetate, neryl acetate etc.). Other peaks were found as 3-cyano-2,5-dimethyl-pyrazine. The amount of volatile materials such as $\alpha$-pinene, myrcene, $\beta$-phellanderene, L-linalool, citronellal, citronellyl acetate, $\beta$-caryophyllene were detected abundantly among the volatile materials.

• Food Science and Preservation
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• v.7 no.1
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• pp.33-37
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• 2000

Effects on keeping quality according to the different package environment in cabbage and brccoli were studied. Opened 2 mil LDPE (low density polyethylene) sealed 4 mil LDPE and BA(barrier polyethylene) were used as package films. Weight loss was markedly in opened 2 mil LDPE in cabbage and broccoli as 6 and 28%, respectively. Carbon dioxide was higher in seal-packaging cabbage and broccoli with BA held at 4 $^{\circ}C$ was above 15 and 31% within 15 days, respectively, while oxygen content was depleted to 2% or less after 10 days. The main difference between volatile sulfur-containing compounds produced from cabbage and broccoli were the relative quantities and rates of production of hydrogen sulfide, carbonyl sulfide, methanethiol and dimethyl disulfide in opened 2 mil LDPE , sealed 4 mil LDPE and barrier bags during storage.

• Analytical Science and Technology
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• v.15 no.1
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• pp.80-86
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• 2002

The simultaneous analysis of the odorous compounds designated by law in Korea and Japan was examined with the thermal desorber gas chromatography-mass spectrometry using one column. The approximate concentrations of trimethyl amine, acetaldehyde, methyl mercaptan and dimethyl sulfide were estimated. Styrene, dimethyl disulfide, propionaldehyde, n-butyl aldehyde, i-butyl aldehyde, n-valeraldehyde, i-valeraldehyde, ethyl acetate, toluene, xylene, methyl i-butyl ketone and i-butanol were detected at concentrations of the detection limits of their threshold values. As a typical example of simultaneous analysis of the odorous compounds, the volatile organic compounds emitted from compost procedure of food waste were concentrated and analyzed with thermal desorber/GC/MSD, and major malodorous compounds were estimated from the concentrations and threshold values of the detected components. From the result of analysis, 34 compounds were confirmed and among them, trimethyl amine, i-valeraldehyde, methyl mercaptan, methyl allyl sulfide, dimethyl sulfide, acetaldehyde, ethanol, n-butyaldehyde were expected to attribute to the odor in order of strength.

• International Journal of Automotive Technology
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• v.7 no.4
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• pp.501-508
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• 2006

The effect of chemical additives, such as dimethyl ether(DME), ethanol, carbon disulfide on the soot formation were examined numerically. ill this study, the Frenklach soot mechanism was used as a base mechanism to predict the soot formation in the ethane flame. The combination of Westbrook's DME mechanism, Marinov's ethanol mechanism, and chemical kinetic mechanism for hydrogen sulfide and carbon disulfide flames was made with the base mechanism because the DME, ethanol, $CS_2$ additives are added into the ethane fuel. CHEMKIN code was used as a numerical analysis software to simulate the effect of chemical additives on reduction of the polycyclic aromatic hydrocarbons(PAH's) which are soot precursors. From the numerical results it is observed that addition of DME, ethanol and $CS_2$ into ethane fuel can reduce PAH species significantly. That means theses additives can reduce soot formation significantly. Results also strongly suggest suppression of soot formation by these additives to be mainly a chemical effect. Hand OH radicals may be the key species to the reduction of PAH species for additives.