• 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 Applied Science and Technology
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• v.3 no.1
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• pp.57-64
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• 1986

1-(carboxyalkyl) trimethyl ammonium chlorides such as 1-(carboxyundecyl) trimethyl ammonium chloride and 1-(carboxytridecyl) trimethyiammonium chloride were synthesized by the reaction of ${\alpha}-bromoalkanoic$ acid with trimethyl amine hydrochloride. In other hand, (carboxymethyl) alkyl dimethyl ammonium chlorides such as (carboxymethyl) dodecyl dimethyl ammonium chloride and (carboxymethyl) tetradecyl dimethyl ammonium chloride were synthesized by the reaction of alkyl dimethylamine with sodium chloroacetate. The four kinds of alky carboxy betaine such as 2-(trimethylammonio) dodecanoate, 2-(trimethyl ammonio) tetradecanoate, (dodecyl dimethylammonio) ethanoate and (tetradecyl dimethyl ammonio) ethanoate were prepared from 1-(carboxyalkyl) trimethyl ammonium chlorides or (carboxymethy1) alkyl dimethyl ammonium chlorides. The surface activities including surface tension, emulsifying power, foaming power, foam stability, deflocculating effect, effectiveness of wettability and solubilizing effect were measured and also critical micelle concentration and hydrophilic-lipophilic. balance(HLB) were evaluated. These carboxy betaines show good surface activities as O/W type emulsifing agent and detergent.

• Bulletin of the Korean Chemical Society
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• v.33 no.3
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• pp.1047-1051
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• 2012

The nucleophilic substitution reactions of (2R,4R,5S)-(+)-2-chloro-3,4-dimethyl-5-phenyl-1,3,2-oxazaphospholidine 2-sulfide with X-pyridines are investigated kinetically in acetonitrile at $5.0^{\circ}C$. The free energy relationships for substituent X variations in the nucleophiles exhibit biphasic concave upwards with a break point at X = 3-Ac. Unusual positive $\rho_X$ (= +4.73) and negative ${\beta}_X$ (= -0.75) values are obtained with the weakly basic pyridines, and rationalized by the isokinetic relationship with isokinetic temperature at $t_{ISOKINETIC}=39.3^{\circ}C$. A concerted mechanism involving a change of nucleophilic attacking direction from a frontside attack with the strongly basic pyridines to a backside attack with the weakly basic pyridines is proposed on the basis of greater magnitudes of selectivity parameters ($\rho_X$ = -6.15 and ${\beta}_X$ = 1.11) with the strongly basic pyridines compared to those ($\rho_X$ = 4.73 and ${\beta}_X$ = -0.75) with the weakly basic pyridines.

• Bulletin of the Korean Chemical Society
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• v.7 no.2
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• pp.116-120
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• 1986

Irradiation of 1,4-diphenyl-1,3-butadiyne and 5,5-dimethyl-1-phenyl-1,3-hexadiyne with methanol yields 1:1 polar addition products, [E]- and [Z]-1,4-diphenyl-1-methoxy-1-buten-3-yne and [E]- and [Z]-5,5-dimethyl-1-methoxy-1-phenyl-1-hexen-3-yne, respectively. These geometrical isomers were converted into each other reaching the photostationary state on irradiation with 300 nm UV light. The photoaddition reaction of 1,4-diphenyl-1,3-butadiyne and 5,5-dimethyl-1-phenyl-1,3-hexadiyne with methanol seems to proceed from the zwitterionic lowest excited state.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.606-612
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• 1988

The volatile flavor compounds of fresh and dried shiitake mushrooms(Lentinus edodes) were extracted by simultaneous steam distillation-extraction apparatus, and analyzed by combined GC and GC-MS, and effects of pH on the formation of volatile compounds in fresh shiitake mushroom were investigated. Of the 29 compounds identified from fresh shiitake mushroom, the main volatile compound was 1-octen-3-ol comprising about 74.7% of the total volatiles and that in dried shiitake mushroom was 1, 2, 4-trithiolane comprising about 66.3%. With the exception of above two compounds, 3-octanone, 1-octen-3-one, 3-octanol, cis-2-octenal, n-octanol and cis-2-octenol as $C_8$ compounds were identified. Carbon disulfide, dimethyl disulfide, dimethyl trisulfide, 1-(methyl thio)-dimethyl disulfide, 1, 2, 4, 5-tetrathiane as sulfurous compounds were also identified. The formation of $C_8$ compounds in fresh shiitake mushroom during immersion was dominant in the range of pH 6.0 to 7.0, while the formation of sulfurous compounds in the range of pH 8.0 to 9.0.

• Journal of the Korean Chemical Society
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• v.38 no.5
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• pp.377-381
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• 1994

New bis-crown ethers containing siloxane chain were synthesized. 1,3-Bis(trimethylsiloxy)-1,3-dimethyl-1,3-dipentaoxacyclohexadecamethyl disiloxane (1) was synthesized by reaction of 3-methylene-16-crown-5 (8) with 1,3-bis(trimethylsiloxy)-1,3-dimethyl disiloxane (10) in the presence of Pt catalyst. 1,1,3,3,5,5-Hexamethyl-1,5-dipentaoxacyclohexadecamethyl trisiloxane (2) was synthesized by the reaction of crown ether (8) with 1,1,3,3,5,5-hexamethyl trisiloxane (11) in the presence of Pt catalyst. 3-Methylene-13-crown-4 (7), 3-methylene-16-crown-5 (8), and 3-methylene-19-crown-6 (9) were synthesized by the reaction of triethylene glycol (3), tetraethylene glycol (4), and pentaethylene glycol (5) respectively with 3-chloro-2-chloro-methyl-1-propene (6) in the presence of NaH.

• Journal of the Korean Chemical Society
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• v.42 no.4
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• pp.13-482
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• 1998

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.4
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• pp.513-518
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• 2005

Volatile compounds of $\gamma-irradiation$ leeks (Aillum tuberosum R.) were isolated by simultaneous steam distillation and extraction method (SDE) and analyzed by gas chromatography/mass spectrometry (GC/MS) along with the non-irradiated sample. Leeks were irradiated at dose of 20 kGy and non-irradiated samples were considered as control sample. 56 and 54 compounds were identified in non-irradiated and irradiated samples, respectively. These components included the functional groups; alcohols, aldehydes, esters, ketones, N- and S-containing compounds. S-containing compounds such as dimethyl trisulfide, methyl-(Z)-l-proenyl trisulfide, dimethyl disulfide, 3-ethyl-l,2-dithi-5-ene and methyl allyl disulfide were the major compounds. Methyl-(Z)-l-propenyl trisulfide, diallyl trisulfide, (E)-2-hexanal and 3-ethyl-l,2-dithi-5-ene were clearly decreased by the $\gamma-irradiation$, but dimethyl disulfide, diallyl sulfide, allyl methyl sulfide and pyridine were increased by the $\gamma-irradiation$.

• Journal of Life Science
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• v.16 no.7 s.80
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• pp.1243-1249
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• 2006

Volatile flavor compounds in commercial crab-like flavorants were compared by mean of solid phase microextraction(SPME) and liquid continuous extraction (LLCE)/GC/MSD methods. A total of 86 volatile flavor compounds were detected. Of these, 71 were positively identified consisting mainly of sulfur-containing compounds (13), aldehydes (3), ketones (2), esters (26), alcohols (5), aromatic compounds (3), terpenes (8), acids (2) and miscellaneous compounds (9). SPME method was more effective than LLCE method in detection of volatile components in commercial crab-like flavorants. Eight S-, N-containing compounds such as dimethyl sulfide, dimethyl disulfide, dipropyl disulfide, 3-(methylthio)propyl acetate, 3-(methylthio) propanal, 3-(methylthio) propanol, 2-methyl-3-(methylthio) pyrazine and 2-methyl-5-(methylthio) pyrazine, 8 esters such as styrallyl acetate, ethyl acetate, isoamyl acetate, benzyl acetate, ethyl pentanoate, butyl pentanoate, isoamyl pentanoate and furfuryl acetate were considered as major components in crab-like flavorants.

• The Korean Journal of Physiology and Pharmacology
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• v.5 no.2
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• pp.157-163
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• 2001

The effects of dimethyl sulfoxide (DMSO) were studied in two groups of Xenopus oocytes, one expressing ATP sensitive $K^+\;(K_{ATP})$ channel comprised of sulfonylurea receptor SUR1 and inwardly rectifying $K^+$ channel subunit Kir6.2, and the other expressing renal $K_{ATP}$ channel ROMK2. At concentrations of $0.3{\sim}10%$ (vol/vol) DMSO inhibited whole cell Kir6.2/SUR1 currents elicited by bath application of sodium azide (3 mM) in a concentration-dependent manner. The inhibition constant and Hill coefficient were 2.93% and 1.62, respectively. ROMK2 currents, however, was not affected significantly by DMSO. The results support the idea that DMSO inhibits $K_{ATP}$ channel expressed in Xenopus oocyte through a protein-specific mechanism(s) that remains to be further elucidated.