• Title, Summary, Keyword: Thiocyanate

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The Change of Thiocyanate (Goitrogen) Amount, Indolylmethyl Glucosinolate Content and Myrosinase Activity in Redish Kimchi during Fermentation (무우김치 숙성 중 thiocyanate(gitrogen)함량, 기질(indolylmethyl glucosinolate) 함량 및 myrosinase 활성도 변화에 관한 연구)

  • Mee Ree Kim;Hei Soo Rhee
    • Korean journal of food and cookery science
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    • v.5 no.1
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    • pp.1-8
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    • 1989
  • The study on the change of general properties of Kagdugi during dfermentation reveals that around the third day of fermentation, optimum for good flavor, the pH decreased to around or below 4 while the acidity increased gradually. The relative amount of thiocyanate in the radish Kimchi homogenate decreased to 73% after 1 day and after 3 days to 32% of control. And the content of indolylmethyl glucosinolate and total myrosinase activity in the tissue of radish Kimchi decreased gradually and on 3rd day to 25% and 4% of control, respectively. On the other hand the concentration of ascorbic acid in the radish Kimchi was found to vary around 1mM. Based on these results, the gradual decline of thiocyanate formation in the radish Kimchi homogenate is concluded to be caused by the gradual decomposition of indolylmethyl glucosinolate and the decline of myrosinase activity, which are directly affected by the change of pH during fermentation.

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The effect of the ammonium thiocyanate on the fermentation of the yeasts.(Saccharomyces brenerei-Hefe-Rasse XII, Saccharomyces formosensis No. 396 IAM) and Saccharomyces cerevisiae IAM) (Ammonium thiocyanate 농도가 주정효모(Saccharomyces brenerei Hefe-Rasse XII, Saccharomyces formosensis No. 396 IAM) 및 맥주효모(Saccharomyces cerevisiae IAM)의 발효작용에 미치는 영향)

  • 조운복;이상태
    • Korean Journal of Microbiology
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    • v.6 no.1
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    • pp.29-35
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    • 1968
  • There are many reports on the effect of salts to the fermentation of the yeasts, but there are a few reports on the effect of the ammonium thiocyanate(NH$_4CNS$) on the fermentation of the yeasts(Saccharomyces brenerei-Hefe-Rasse X11, Saccharomyces formosensis No. 396 IAM and Saccharomyces cerevisiae IAM). A study has been made on the effects of the ammonium thiocyanate on the fermentation of the above yeasts. The results of the research are as belows: 1) The addition of 0. 00001 mol. of ammonium thiocyanate makes the fermentation of the yeast(Sacch. formosensis No. 39 IAM) facilitate, but has not influenced the another yeast (Sacch. brenerei-Hefe-Rasse XII). 2) The addition of 0. 001 mol. of ammonium thiocyanate makes fermentation of Rases XII the fastest, but the on other yeast (Sacch. formosensis No - 396 IAM) was accelerated by the addition of 0. 1 mol., and it seems to have abnormal fermentation by the addition of 0. 0001 mol. The addition of ammonium thiocyanate(0. 00001-0. 001 mol.) inhibited the fermentatirn of the yeast(Sacch. cerevisiae IAM), but the concentration of 0. 1 mol. does not interrupt the fermentation of Sacch. cerevisiae IAM and increased the fermentation. 3) The order of effects to the fermentation of each yeast is Sacch. brenerei-Hefe-Rasse XII, Sacch. formosensis No. 396 IAM, Sacch. cerevisiae IAM.

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Polarographic Studies on the Kinetics of Cu(II)-thiocyanate and the Adsorption Wave of Cu(I)-thiocyanate (Polarography에 依한 Cupric-thiocyanate의 Kinetics와 Cuprous-thiocyanate의 Adsorption Wave에 關한 硏究)

  • Hwang, Jung-Euy;Chung, Chong-Jae;Son, Moo-Young;Park, Yu-Chul
    • Journal of the Korean Chemical Society
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    • v.14 no.3
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    • pp.213-219
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    • 1970
  • In the presence of hydrogen peroxide, the effects of temperature and pH to the catalytic reaction velocity of cupric -thiocyanate and the quantities of reduction products adsorbed on the D.M.E. have been studied by polarographic method. According to these experiments, the following empirical equation has been derived for the relation among temperature $T_i$, concentration of hydrogen ion $pH_i$ and adsorbed cuprous-thiocyanate in moles/$cm^2Z_{ij}$, and rate constant log$K_{ij}$ $$log\;K_{ij}=\frac{1}{T_i}\{A(pH_j)+B\}+C(pH_j)+D$$ $$Z_{ij}=\frac{1}{T_i}\{{\alpha}(pH_j)^{\frac{1}{2}}+{\beta}\}+{\gamma}(pH_j)^{\frac{1}{2}}+{\delta}$$ where, A,B,C,D and {$\alpha},{\beta},{\gamma},{\delta}$ are constants. The Calculated values by both equations are well agreed with empirical values within 8% in the error.

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Determination of Goitrogenic Metabolites in the Serum of Male Wistar Rat Fed Structurally Different Glucosinolates

  • Choi, Eun-Ji;Zhang, Ping;Kwon, Hoonjeong
    • Toxicological Research
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    • v.30 no.2
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    • pp.109-116
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    • 2014
  • Glucosinolates (GLSs) are abundant in cruciferous vegetables and reported to have anti thyroidal effects. Four GLSs (sinigrin, progoitrin, glucoerucin, and glucotropaeolin) were administered orally to rats, and the breakdown products of GLSs (GLS-BPs: thiocyanate ions, cyanide ions, organic isothiocyanates, organic nitriles, and organic thiocyanates) were measured in serum. Thiocyanate ions were measured by colorimetric method, and cyanide ions were measured with CI-GC-MS. Organic isothiocyanates and their metabolites were measured with the cyclocondensation assay. Organic nitriles and organic thiocyanates were measured with EI-GC-MS. In all treatment groups except for progoitrin, thiocyanate ions were the highest among the five GLS-BPs. In the progoitrin treated group, a high concentration of organic isothiocyanates (goitrin) was detected. In the glucoerucin treated group, a relatively low amount of goitrogenic substances was observed. The metabolism to thiocyanate ions happened within five hours of the administration, and the distribution of GLSs varied with the side chain. GLSs with side chains that can form stable carbocation seemed to facilitate the degradation reaction and produce a large amount of goitrogenic thiocyanate ions. Because goitrogenic metabolites can be formed without myrosinase, the inactivation of myrosinase during cooking would have no effect on the anti-nutritional effect of GLSs in cruciferous vegetables.

QM/MM-MD 방법을 이용한 용액 속에서의 Potassium Thiocyanate의 Association/Dissociation Dynamics 연구

  • Nam, Hye-Rim;Ghosh, ManikKumer;Choe, Cheol-Ho
    • Proceeding of EDISON Challenge
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    • pp.347-358
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    • 2014
  • 본 논문에서는 양자 역학적 분자 동역학(Quantum Mechanical/Molecular Mechanical-Molecular Dynamics, QM/MM-MD)을 통해 수용액에 녹아 있는 Potassium Thiocyanate의 dynamics를 연구했다. Umbrella sampling technique을 활용하여 association/dissociation에 해당하는 Free energy surface를 구했다. 두 개의 Free energy minimum이 녹아 있는 두 이온의 center of mass 사이의 거리가 $4{\AA}$일 때와 $5{\sim}6{\AA}$ 부근일 때 나타났으며 $4{\AA}$일 때 더 안정 했다. 본 논문에서는 $4{\AA}$일 때를 Contact Ion Pair(CIP) $6{\AA}$일 때를 Dissociation Ion Pair(DlP)라고 칭했다. 이 minimum들이 무엇인 지를 밝혀 내기 위해 추가 연구를 수행하였다. Free energy 상에서 가장 안정 할 때(CIP) solute인 Potassium thiocyanate의 구조를 살펴 봤더니 Potassium ion은 Thiocyanate ion의 Sulfur보다 Nitrogen side를 선호하였다. 그 원인을 알아보기 위해 salvation shell의 구조를 Radial distribution function을 통해 살펴 봤더니 물 분자가 Nitrogen보다 Sulfur와 더 강한 상호작용을 하고 있었다. 그로 인해 Potassium ion이 Nitrogen을 선호한단 결과가 나온 것이다. 한편, 두 번째 minimum은 물 분자가 Potassium 이온과 Thiocyanate 이온 사이에 flexible하게 bridging을 하는 구조였다. 또한 단순 양자 계산을 통해서도 비슷한 구조를 얻을 수 있었다. 그러나 QM 계산은 0K에서 수행하는 것이기 때문에 엔트로피 효과가 없는 계산이지만 본 연구는 온도 300K로 실제 용매와 가깝게 수행함으로써 고정되어 있는 구조가 아니라 엔트로피와 엔탈피가 균형적으로 존재하는 실제 용액 속에서의 구조를 처음으로 보여주는 것이다.

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Effect of Nitrite, Thiocyanate and Ascorbic acid on N-nitrosamine Formation in Salted and Dried Yellow Corvenia under Simulated Gastric Digestion (염건조기의 인공소화시 Nitrite, Thiocyanate 및 Ascorbic acid가 N-nitrosamine의 생성에 미치는 영향)

  • 이수정;신정혜;김정균;성낙주
    • Journal of Food Hygiene and Safety
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    • v.15 no.2
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    • pp.101-107
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    • 2000
  • This experiment was conducted to investigate the effect of NA formation in the human body with salted and dried yellow corvenia(Gulbi, Pseudosciaena manchurica) steamed for 30 minutes and incubated in 10 ml simulated saliva and 40 ml gastric juice at 37。C for 2 hours. And the experiment studied the NA formation after nitrite, thiocyanate and ascorbic acid treatment under simulated gastric conditions. N-nitrosodimethylamine(NDMA) was not detected when nitrite was not added to the digestate mixture. And then increasing the nitrite concentration from 0.5 mM to 8 mM gave a slight increase in the NDMA formation at all level of Gulbi utilized in the experiment. In contrast to the change of the nitrite concentration, the increase of the amount of Gulbi didn't show any marked influence on NDMA formation. At all level of thiocyanate(1∼6.4 mM) tested, concentration of NDMA was still proportional to the nitrite concentration. In the catalytic ability of thiocyanate at another high level of nitrite(100 mM) no catalytic activity was observed up to the level of 8mM thiocyanate. The same amounts of salted fish(10 g) and ascorbic acid levels in each single digestate were used to prevent NDMA formation. No prevention effect was observed at nitrite concentration of 0.5 mM and 1 mM. Most importantly, the decrease of NDMA concentration, by the increase of ascorbic acid absolutely, was remarkably shown when nitrite concentration was high. On the contrary, according to the degree of ascorbic acid, the higher the amount of nitrite the higher the prevention of NDMA formation.

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Enhancement of Au·Ag Leaching by Mechanochemical Activation and Thiourea-Thiocyanate Mixing Solution (기계적-화학적 활성화와 티오요소-티오시안산염 혼합용액에 의한 Au·Ag 용출 향상)

  • You, Don-Sang;Park, Cheon-Young
    • Journal of the Korean earth science society
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    • v.35 no.6
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    • pp.401-411
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    • 2014
  • In order to enhance the Au Ag leach rate, a mechanochemical activation process and a mixed thiourea-thiocyanate solution has been applied to Au concentrate. To achieve mechanochemical activation, the Au concentrate was mechanically ground using a dry and a wet process. The results of a particle size distribution analysis and an XRD analysis, average particle size and crystallite size were much smaller in the dry-sample than in the concentrate sample. As well the size was smaller in the wet-sample than in the dry-sample. In SEM and XRD analysis, the amorphization effect was observed in the wet-sample due to mechanochemical activation. Au Ag leaching experiments were carried out with a thiourea solution, a thiocyanate solution and a mixed thiourea-thiocyanate solution. The Au Ag leach rate was much greater in the dry-ground-sample than in the concentrate sample, and the leach rate was greater in the wet-ground-sample than in the dry-sample. The Au Ag leach rate was much greater in the thiocyanate solution than in the thiourea solution, and the leaching rate was much greater in the mixed thiourea-thiocyanate solution than in the thiocyanate solution. Up to a 99% leach rate for Au Ag were only achieved in the wet-sample using the mixed thiourea-thiocyanate leaching solution.

Kinetic Studies on the Reaction of Thiocyanate with Di-$\mu$-oxobis-(aquaoxalatooxomolybdate (V)) in Acid Media (산성수용매에서 이-$\mu$-옥소비스-(아쿠아옥살라토옥소몰리브덴 (V)) 산이온과 티오시안산이온의 반응)

  • Chang-Su Kim;Chang-Yong Kwon;Moon-Pyoung Yi;Chann-Woo Kim
    • Journal of the Korean Chemical Society
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    • v.29 no.6
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    • pp.623-628
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    • 1985
  • Rate constants for complexing with thiocyanate after ring opening of molybdenum-oxalate in acid media were obtained spectrophotometrically at 460nm. The acid-assisted dissociation of molybdenum-oxalate and the reaction of thiocyanate with oxalatooxomolybdenum (V) complex in acid media were investigated with thiocyanate and hydrogen ion concentration. The kinetic data indicate that molybdenum-oxalate is protonated to a limited extent in acid media and the protonated complex is responsible for an increase in rate for the reaction of thiocyanate with oxalatooxomolybdenum (V) complex. Replacement of an oxalate ligand in acid media has been interpreted in terms of dissociative mechanism involving bond-breaking of the oxygen trans to the yl oxygen.

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Study on the stability of ammonium cobalt thiocyanate solution and the formation of perthiocyanuric acid (Ammoninm Cobalt Thiocyanate 용액의 안정도 및 Perthiocyanuric acid의 생성반응에 관한 연구)

  • 최종인
    • YAKHAK HOEJI
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    • v.7 no.2_3
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    • pp.36-41
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    • 1963
  • Cobalt thiocyanate ion에 미치는 영향을 연구하였다. Cobalt ion이 $NH_{4}CNS$ 용액에 의해서 생성되는 ion의 색의 transmittance는 확산에 의하여 적어지며, 황산존재하에서는 황산의 양과 Transmittance 사이에 비례적 관계가 있다. 염산 및 질산도 역시 Transmittance의 값에 영향을 미치기는 하나 염산의 경과에는 이 착 ion이 황산존재하보다 다소 불안정하며 질산에 의해서는 안정화가 극히 적어서 단시간내에 Perthiocyanuric acid로 인정되는 물질로 분해한다. 또한 그 Transmittance가 과량의 광산존재하에서 적어지는 현상으로 부터 $Co(SCN)^{2-n/_{$ n/의 n의 값이 커지는 것은 ether에 이행하는 SCN-을 Volhard 씨법으로 정량함으로서 확증하였다.

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A Polarographic Study of Mo-thiocyanate (V) Complex (Mo-Thiocyanate (V) 錯物의 電極還元 反應에 關한 硏究)

  • Sang-O Oh;Yu-Chul Park
    • Journal of the Korean Chemical Society
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    • v.14 no.2
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    • pp.141-145
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    • 1970
  • The reduction of Mo-thiocyanate (V) complex on dropping mercury electrode has been studied at ionic strength 0.6 with pH less than 2.3. D-C polarogram obtained from acidic solutions are reversible, diffusion controlled current. The electrode reaction of Mo-thiocyanate(V) may be represented as follows. $MoO(SCN)_3\;+\;2H^+\;+\;2e\;{\to}\;Mo(SCN)_2{^+}\;+\;H_2O\;+\;SCN^-$From this reaction, the half wave potential assumed to be $E_{1/2}\;=\;E_0'\;-\;0.059\;pH\;-\;0.03\;log{\;frac{[Mo(SCN)_2{^+}][SCN^-]}{[MoO(SCN)_3]}}$Considering the dissociation of this complex, however, it was estimated that the electrode reaction may be written by. $MoO^{+3}\;+\;3SCN^-\;+\;2H^+\;+\;2e\;{\to}\;Mo(SCN)_2{^+}\;+\;SCN^-\;+\;H_2O$.

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