• The Korean Journal of Food And Nutrition
• /
• v.10 no.4
• /
• pp.539-543
• /
• 1997

This study was carried out to investigate the Chinese and Baek-Seok chive. We collect the volatile components of Chinese and Baek-Seok chive by dynamic head space method. Chinese chive was analyzed by Gas chromatography-Mass Spectrometry(GC-MS). 28 components including 20 sulfides, 5 alcohols, 1 benzene and 2 aldehydes compounds were identified in samples, Also Baek-Seok chive was analyzed by GC-MS. 32 components including 19 sulfides, 10 alcohols, 2 benzonoides and 1 aldehyde compounds were confirmed.

• Korean journal of food and cookery science
• /
• v.1 no.1
• /
• pp.33-39
• /
• 1985

The volatile sulfur components from two varieties of radishes ('Taeback' and 'Altali'), obtained by steam distillation and solvent ($CCl_4$) extraction, were isolated and charac-terized by GC/MS analysis. The GC profile of the volatile sulfur com-pounds in the steam distillates from two types of radishes was quite similar. 4-Me-thylpentyl, 3-methylthiopropyl, 4-methylthio-3-butenyl, 4-methylthiobutyl and 5-methyl-thiopentyl isothiocyanates, 5-methylthio-4-pentenenitrile, 1-methylthio-3-pentanone, and dimethyl sulfides were commonly identified. In the $CCl_4$ extract, 4-methylsulfinyl-3-bu-tenyl isothiocyanate was obtained as another major constituent. Whereas 4-methylthiobutyl isothiocyanate was found to be a predominent component in the steam distillate, 4-methylthio-3-butenyl isothiocyananate was a major one in the $C1_4$ extract.

• Food Science and Biotechnology
• /
• v.14 no.2
• /
• pp.297-300
• /
• 2005

Effects of allyl sulfides on kinetic behavior of cytochrome P450 1 (CYP1)-catalyzed ethoxyresorufin O-deethylase (EROD) activity were studied using microsomes from benzo[a]pyrene-treated human hepatoma cells. Apparent $K_m$ and $V_{max}$ values were calculated as $2.8\;{\mu}M$ and $3.0\;{\mu}mol$ resorufin/min/mg protein based on Lineweaver-Burk plot of microsomal EROD activity, respectively. Diallyl disulfide (DADS) and diallyl trisulfide (DATS) affected $K_m$ and $V_{max}$ values of EROD activity and acted as mixed-type inhibitors for CYP1 isozymes. Apparent Ki values of DADS and DATS were calculated as 1.07 and 0.88 mM, respectively, by re-plotting slopes of Lineweaver-Burk plot and inhibitor concentrations.

• The Korean Journal of Food And Nutrition
• /
• v.9 no.4
• /
• pp.434-437
• /
• 1996

This study was carried out to investigate the Allium tuberosum. We collect the volatile components of Allium tuberosum by dynamic head space method. Sample was analysed by gas chromatography-mass spectrometry(GC-MS). Twenty on components, 14 sulfides, 12 alcohols, 2 aldehyde, 1 furan, 1 acid and 1 benzene were confirmed in sample.

• Food Science and Biotechnology
• /
• v.17 no.5
• /
• pp.1032-1037
• /
• 2008

Lowly volatile heterocyclic sulfur compounds generated in autoclaved garlic extract were isolated and identified, and their antimicrobial activity was determined. Two kinds of unusual volatile sulfur compounds were separated from heated garlic by preparative recycling high performance liquid chromatography (HPLC), and identified by gas chromatography (GC)-mass spectrometry (MS) and $^1H$-nuclear magnetic resonance (NMR). They had heterocyclic structures with 4 to 5 sulfur atoms in the molecules. 4-Methyl-1,2,3-trithiolane (MTTT) is highly volatile and was not able to be concentrated, and was identified by GCMS only. MTTT and 6-methyl-1,2,3,4,5-pentathiepane (MPTP) are lowly volatile and were obtained in pure states to be positively identified for the first time. All 3 heterocyclic sulfur compounds began to appear by the time when the early-formed diallyl sulfides started to disappear. The minimum inhibitory concentration range of MTTT and MPTP was determined to be between 1 and 6 ppm against all yeasts tested. MTTT and MPTP were lowly volatile and sparingly soluble in water.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.27 no.1
• /
• pp.16-23
• /
• 1998

Effect of Fermentation temperature on the changes of chemical components in Kakudgi during fermentation was investigated by measuring free sugar, organic acid and volatile compounds up to 57 days at several temperatures. The mannitol was increased in palatable period in contrast with those of other free sugars. The higher the initial fermentation temperature was and the longer the initial fermentation time at 2$0^{\circ}C$ was, the faster the second increasing period was and the less the initial contents was. Lactic acid was increased 6~31 times from a little amount at the initial period. The higher the initial fermentation temperature was and the more the increasing content was. But malic acid which was abundant(55.1% of total nonvolatile organic acid) in the initial fermentation period was remarkably decreased in the palatable period. The change of the sulfides among the volatile compounds was remarkable. Methyl allyl sulfide which was a little in the initial fermentation period was remarkably increased in the final fermentation period, and the correlation coefficients between the content of methyl allyl sulfide and aroma in sensory evaluation were high. It could be suggested that the fermentation temperature should be set to 4$^{\circ}C$ after fermentating at 2$0^{\circ}C$ for 36 hours in the view point of keeping the Kakdugi taste and quality well because of high content of free sugar and nonvolatile organic acids.

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

• Journal of Korean Society of Water and Wastewater
• /
• v.23 no.6
• /
• pp.843-853
• /
• 2009

The sediment samples were collected from Seonakdong River and were analyzed for sulfide species such Acid Volatile Sulfide(AVS) and Elemental Sulfur(ES) and Chromium Reducible Sulfide(CRS). Then characteristics of the formation of sulfide species were investigated for six selected samples. Finally the relationship between environmental factors and sulfate reducing rate(SRR) was investigated using two selected samples. Concentrations of AVS and CRS were relatively high, which suggests that organics input to the sediments has been continued until recently and that potential of heavy metals leaching from the sediments is low. SRR in the sediments was closely related to fraction of fine particles(silt+clay) and also to dissolved organic carbon content of the sediment(DOCsed). The dependences of environmental factors such as organic content, temperature, sulfate concentration on the SRR was relatively strong in the selected experiments conducted with the samples from Noksan gate and Daejeo gate samples. The environmental factor dependencies were stronger in the Noksan gate samples than in the Daejeo gate samples, which is probably due to higher surface area of the Noksan gate sediments.

• Environmental Engineering Research
• /
• v.25 no.3
• /
• pp.274-280
• /
• 2020

The marine sediment sustains from the anoxic condition due to increased nutrients of external sources. The nutrients are liberated from the sediment, which acts as an internal source. In hypoxic environments, anaerobic respiration results in the formation of several reduced matters, such as N₂ and NH₄⁺, N₂O, Fe²⁺, H₂S, etc. The experimental results have shown that nitrogen and sulfur played an influential, notable role in this biogeochemical cycle with expected chemical reductions and a 'diffusive' release of present nutrient components trapped in pore water inside sediment toward the bulk water. Nitate/ammonium, sulfate/sulfides, and ferrous/ferric irons are found to be the key players in these sediment-waters mutual interactions. Organonitrogen and nitrate in the sediment were likely to be converted to a form of ammonium. Reductive nitrogen is called dissimilatory nitrate reduction to ammonium and denitrification. The steady accumulation in the sediment and surplus increases in the overlying waters of ammonium strongly support this hypothesis as well as a diffusive action of the involved chemical species. Sulfate would serve as an essential electron acceptor so as to form acid volatile sulfides in present of Fe³⁺, which ended up as the Fe²⁺ positively with an aid of the residential microbial community.

• Journal of Korean Society of Environmental Engineers
• /
• v.36 no.7
• /
• pp.469-475
• /
• 2014

The study investigated the physicochemical characteristics and the ecological risk of the Northport sediment in B city and the releasing properties of heavy metals into seawater during the resuspension also studied. The major components of the sediment are fine silt and clay which contains high organic matter and AVS (Acid volatile sulfide) and the ecological risk of the heavy metals in sediment also very high. The release rate of heavy metals into seawater was in order of Pb>>Cu>Cr>>Zn>Cd during the resuspension in a batch experiment, and the heavy metal release mainly attributed to the oxidation of metal sulfides. Heavy metals which came from easily oxidisable metal sulfides rapidly contaminated seawater within about 1.0 h of the sediment resuspension. The sulfide oxidation during the resuspension increased the residual fraction of heavy metals in the sediment, decreased the organic bound fraction, and changed the other fractions of heavy metals in the sediment. The release of heavy metals from the sediment during resuspension was affected by the resuspension time, the oxidation rate of metal sulfides and resuspended concentration of the sediment particle.