• 한국미생물·생명공학회지
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• 제34권4호
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• pp.338-341
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• 2006

The growth characteristics of sulfur-oxidizing bacteria, Acidithiobacillus thiooxidans AZ11, MET, and TAS were investigated in mineral salt media supplemented with elemental sulfur of 1$\sim$50 g $L^{-1}$. The sulfur oxidation rates of A. thiooxidans. MET and TAS increased highly with increasing sulfur concentration up to 10 g L$^{-1}$, but the rates increased slowly in sulfur concentration over 10 g L$^{-1}$. A. thiooxidans AZ11 showed the parallel increase of sulfur oxidation rate until sulfur concentration increased up to 40 g L$^{-1}$. The maximum sulfur oxidation rates (V$_{max}$) of AZl1, MET and TAS were 1.88, 1.38 and 0.43 g S L$^{-1}$ d$^{-1}$, respectively. The maximum specific growth rates (${\mu}_{max}$) of AZ11, MET, and TAS were 0.33 d$^{-1}$, 0.30 d$^{-1}$ and 0.45 d$^{-1}$, respectively. Although MET and TAS couldn't grow at sulfate concentration of 40 g L$^{-1}$, AZ11 could grow in the presence of 58 g L$^{-1}$ sulfate, the final oxidation product of elemental sulfur.

• 약학회지
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• 제22권4호
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• pp.201-206
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• 1978

The analysis of elemental sulfur by polarography has already been reported in the literature. Only a discussion of the more important factors influencing the analysis is here presented. (1) The effects of pH on the reduction of elemental sulfur are pronounced and the use of buffered solutions for the analysis of elemental sulfur is necessary. The authors found that a pH of 4-6 was found to be reproducible polarograms by use of D.C. polarograph. However, in alkali solvents the plateau of elemental sulfur has a pronounced dip if the concentration of sulfur is as much as 30ppm. (2) A.C. polarographic method shows a very high sensitivity in the case of sulfur reduction, so that the very low concentration of sulfur can easily be determined (about 1ppm). (3) The characteristics of sulfur wave can be formulated according to Stackelberg-Hauck-Hans equation. It was found that the curve of the peak potential of elemental sulfur in A.C. polarography versus logarithm of sulfur concentration was obtained to be straight line with the slope of 29.6 millivolts. This result was well agreed with theoretical consideration. (4) It was assumed that this polarographical methods were applicable to micro-analysis of elemental sulfur in crude oil and its petrochemical products, precipitated sulfur, and sulfur ointments with accuracy and rapidity.

• Biotechnology and Bioprocess Engineering:BBE
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• 제5권1호
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• pp.48-52
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• 2000

An autotrophic sulfur oxidizer, Thiobacillus sp. ASWW-2, was isolated from activated sludge, and its sulfur oxidation activity was characterized. Thiobacillus sp. ASWW-2 could oxidize elemental sulfur on the broad range from pH 2 to 8. When 5-50 g/L of elemental sulfur was supplemented as a substrate, the growth and sulfur oxidation activity of Thiobacillus sp. ASWW-2 was not inhibited. The specific sulfur oxidation rate of strain ASWW-2 decreased gradually until sulfate was accumulated in medium up to 10 g/L. In the range of sulfate concentration from 10 g/L to 50 g/L, the sulfur oxidation rate could keep over $2.0g-S/g-DCW{\cdot}d$. It indicated that Thiobacillus sp. ASWW-2 has tolerance to high concentration of sulfate.

• 한국식품과학회지
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• 제22권1호
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• pp.99-104
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• 1990

옥수수를 아황산의 농도(0.16-0.20%)와 침지시간 (25-50시간)을 달리하여 $52^{\circ}C$에서 침지하면서 침지액의 pH, 옥수수의 흡수성질 전분의 성질을 분석하였다. 침지액의 pH는 침지 5시간까지 급격히 증가하였고 20시간 이후에는 일정한 값을 유지하였다. 침지 중 옥수수의 수분 및 부피증가는 아황산 농도가 증가할수록 감소하였다. 전분의 단백질 함량은 아황산 농도가 증가할수록 증가하였으나, 조회분이나 인은 큰 차이를 보이지 않았다. 전분의 물 결합 능력 및 아밀로그래프의 점도지표는 모두 아황산 농도에 관계없이 침지 35시간에서 가장 높은 값을 보였다. 전분의 팽윤력과 용해도 그리고 NaOH 용액에 의한 호화점도는 아황산 농도가 증가할수록 감소하였다.

• Nutrition Research and Practice
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• 제7권2호
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• pp.89-95
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• 2013

Dietary inorganic sulfur is the minor component in our diet, but some studies suggested that inorganic sulfur is maybe effective to treat cancer related illness. Therefore, this study aims to examine the effects of inorganic sulfur on cell proliferation and gene expression in MDA-MB-231 human breast cancer cells. MDA-MB-231 cells were cultured the absence or presence of various concentrations (12.5, 25, or 50 ${\mu}mol/L$) of inorganic sulfur. Inorganic sulfur significantly decreased proliferation after 72 h of incubation (P < 0.05). The protein expression of $ErbB_2$ and its active form, $pErbB_2$, were significantly reduced at inorganic sulfur concentrations of 50 ${\mu}mol/L$ and greater than 25 ${\mu}mol/L$, respectively (P < 0.05). The mRNA expression of $ErbB_2$ was significantly reduced at an inorganic sulfur concentration of 50 ${\mu}mol/L$ (P < 0.05). The protein expression of $ErbB_3$ and its active form, $pErbB_3$, and the mRNA expression of $pErbB_3$ were significantly reduced at inorganic sulfur concentrations greater than 25 ${\mu}mol/L$ (P < 0.05). The protein and mRNA expression of Akt were significantly reduced at an inorganic sulfur concentration of 50 ${\mu}mol/L$ (P < 0.05), but pAkt was not affected by inorganic sulfur treatment. The protein and mRNA expression of Bax were significantly increased with the addition of inorganic sulfur concentration of 50 ${\mu}mol/L$ (P < 0.05). In conclusion, cell proliferation was suppressed by inorganic sulfur treatment through the ErbB-Akt pathway in MDA-MB-231 cells.

• 한국수소및신에너지학회논문집
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• 제17권3호
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• pp.286-292
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• 2006

Chlamydomonas reinhardtii is a green algae that can use light energy and water to produce hydrogen under anaerobic condition. This work reports the effect of limiting factors on hydrogen production in sulfur deprived anaerobic C. reinhardtii culture. In order to confirm the relationship between hydrogen production and limiting factors such as residual PSII activity and endogenic substrate degradation, the increase in chlorophyll concentration and the decrease in starch concentration was investigated during sulfur deprivation. The overall hydrogen production increased depending on cell density in range of $0.4{\sim}0.96\;g$ DCW/l. At this time, the increase in chlorophyll concentration during 24 h after sulfur deprivation increased in proportion to hydrogen production, however, the decrease in starch concentration was not proportional to that. Therefore, hydrogen production under sulfur deprivation using green alga was closely associated with the residual PSII activity than the endogenic substrate degradation.

• Journal of Nutrition and Health
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• 제29권3호
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• pp.260-266
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• 1996

Eighteen crossbred pigs were weaned at 4 days of age and fed up to 28 days of age to examine the effect of sulfur amino acid content of three diets upon plasma taurine concentration and hepatic cysteinesulfinate decarboxylase activity. The experimental diets consisted of either whey protein (W) or partialy hydrolyzed soy protein (S) as the source of protein. 0.25% methionine was added to the S diet for the third dietary regimen (SM). Sulfur amino acid content(methionine plus cystine)of the three diets was 1.53%, 1.34% and 1.09% for the W, SM and S diet, respectively. Plasma taurine concentration from the pigs fed the three experimental diets reflected the total sulfur amino acid content of the diet. The S diet resulted in a significantly lower plasma tarrine level than the W and SM diets throughout the experiment. After three weeks, pigs fed the W diet had significantly higher plasma taurine concentration than those fed SM diet. Therfore it appears that taurine requirement of the pig depends on the sulfur amino acid contents of the diets and the conversion o sulfur amino acid to taurine seemed not to be limited by any factor when sulfur amino acid was below 1.53% of the diet. There was no significant difference between three dietary groups in hepatic cysteinesulfinate decarboxylase activity and this suggests that the reduced cysteinesulfinate decarboxylase activity due to high sulfur amino acid in the diet may not occur in the pig liver.

• 한국환경과학회지
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• 제4권2호
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• pp.215-222
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• 1995

Thiokncillus neapolitanus R-10 isolated from sludge of night soil, showed an oxidizing activity on several malodorous sulfur compounds. The microbe successfully utilized hydrogen sulfide(H2S), methy mercaptan(MM), dimethyl sulfide(DMS) and dimethyldisulfide(DMDS) during the batch culture reaction, of which H2S was rather rapidly oxidized. To examine the ability for removal of malodorous sulfur compounds, various concentrations of sulfide substrates were supplemented separately to basal medium and their responses were investigated. As the concentration of sulfide was increased, growth was accelerated within three days of cultivation. 2.5mM was the most favorable substrate concentration of sulfide added for all cases tested. However, when the concentration of sulfur compounds were raised over 4M, they behaved as a growth inhibitor.

• 한국환경보건학회지
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• 제17권1호
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• pp.1-12
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• 1991

The atmospheric SO$_{2}$ concentrations and water soluble sulfur contents in Ginkgo biloba were measured and analyzed in auto-measuring station, Kwangleung, and Yongmun from August 5 to October 21, 1990. The results of the study are as follows: 1. Atmospheric SO$_{2}$ concentrations between the seoul area(Pulkwang, Ssangmun, Myonmok, Oilurn) in which the concentrations exceeded the air quality standards and the surburb of seoul (Kwangleung, Yongmun) revealed the significant difference (p<0.01). 2. Water soluble sulfur contents in Ginkgo biloba in autumn were higher than those in Ginkgo biloba in summer (p<0.01). Water soluble sulfur contents in leaves showed a significant difference between seoul and its surburb(p<0.01). 3. Correlation between atmospheric SO$_{2}$ concentration and water soluble sulfur content of Ginkgo biloba in autumn was as follow Y=0.2714+9.8123 X, r=0.6362 (X: Airborne SO${_2}$ Concentration according to sampling location, Y: Water Soluble Sulfur Contents)

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2000년도 추계학술대회
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• pp.209-212
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• 2000

As a bench-scale study, transformation of nitrate to nitrogen gas under anoxic condition was determined by using autotrophic denitrifiers containing Thiobacillus denitrificans and elemental sulfur as an electron donor. The research objective is to measure the basic kinetic parameters of autotrophic denitrification reaction on the removal efficiency of nitrate. The results showed that nitrate was almost completely transformed to nitrite in the first 4 days of column operation. After 2 days of accumulation of nitrite, its concentration slowly decreased and the compound was detected less than 0.5 mg/L in 14 days. In the experiment, sulfate concentration in the effluent was the 70~90 mg-S/L and the pH was maintained around pH 7.5. When nitrate concentration of bank filtrate in the real field is considered, this sulfate concentration seems to be acceptable. At 17 cm from the bottom of the column, the effluent showed the highest nitrite concentration, and nitrate concentration decreased rapidly to the Point of 33 cm from the bottom. The results suggest that an appropriate thickness of permeable reactive barriers is about 30 cm.