• Fisheries and Aquatic Sciences
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• v.1 no.2
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• pp.209-215
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• 1998

Trypsin-like enzyme was purified from shrimp hepatopancreas through Q-Sepharose ionic exchange, benzamidine Sepharose-6B affinity, and Superdex 75 gel chromatography. Purity of trypsin-like enzyme was increased 69-fold with $44\%$ yield. The enzyme consisted of a single polypeptide chain with a molecular weight (M.W.) of 32 kDa judged by sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE). The enzyme was completely inactivated by serine enzyme inhibitors such as soybean trypsin inhibitor (SBTI), tosyl-L­lysine chloromethyl ketone (TLCK), and leupeptin. However, the enzyme was not affected by tosyl-L-phenylalanine chloromethyl ketone (TPCK) which is a chymotrypsin specific inhibitor. The enzyme had no activity against benzoyl-tyrosine ethyl ester (BTEE) which is a chymotrypsin specific substrate. The enzyme showed high activity on the carboxyl terminal of Phe, Tyr. Glu, Arg, and Asp. However. no activity was detected against the carboxyl terminal of Pro, Trp, Cys, Gly, Val, and Ala.

• Fisheries and Aquatic Sciences
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• v.1 no.2
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• pp.201-208
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• 1998

A protease, which had no tryptic and chymotryptic activity, was purified from the hepatopancreas of shrimp, P. japonicus, through ammonium sulfate fractionation, Q­Sepharose ionic exchange, benzamidine Sepharose 6B affinity, and Sephacryl S-100 gel chromatography. Molecular weight (M.W.) of the protease was estimated to be 24 kDa by gel filtration and showed a single peptide band by sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE). The protease had a low ratio of acidic to basic amino acids, which is different with pro teases from marine animals. The enzyme was partially inhibited by benzamidine, tosyl-L-lysine chioromethyl ketone (TLCK), phenylmethylsulfonyl fluoride (PMSF), soybean trypsin inhibitor (SBTI), and pepstatin. The enzyme did not have any activity against benzoyl-D,L-arginine p-nitroanilide (BAPNA) or benzoyl-L-tyrosine ethyl ester (BTEE) which is a specific substrate of trypsin and chymotrypsin, respectively. However, the enzyme showed activity forward N-CBZ-L-tyrosine p-nitrophenyl ester (CBZ-Tyr-pNE), N­CBZ-L-tryptophan p-nitrophenyl ester (CBZ-Trp-pNE), and N-CBZ-L-proline p-nitrophenyl ester (CBZ-Pro-pNE). The protease did not showed tryptic and chymotryptic activity, which was not reported in shrimp hepatopancreas.

• Korean Journal of Food Science and Technology
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• v.28 no.2
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• pp.316-323
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• 1996

Flavor components in mash of Takju prepared by different raw materials such as nonglutinous rice, glutinous rice, barley and wheat flour were detected by GC and GC-MS method using non-polar column. Seven alcohols, 15 esters, 10 organic acids, 1 aldehyde, 4 benzenes, 3 phenols, 8 alkans, 2 ketones and 5 others were found in takju after 16 day of fermentation. takju by wheat flour had the most various components of volatile flavor. Treatment with addition starter had less flavor component than that without addition starter in takju by nonglutinous rice. Nine kinds of flavor components including acetic acid ethyl ester, 3- methyl-1-butanol, acetic acid, ethyl benzene, acetic acid 3-methyl butyl ester, 2-phenylethanol, 2,6-di-tert-butyl-4-methyl phenol. plumbagic acid and 1,2-benzenedicarboxylic acid dibutyl ester were commonly detected in all the treatments. Especially, 2,4,0-trimethyl-1,3-benzenediamine was isolated in takju that was made of nonglutinous rice without addition starter. Diethyl sulfide, 4-methoxy benzaldehyde, docosane and 2-methyl propyl octadecanoic acid were isolated from takju by nonglutinous rice with addition starter. Propionic acid ethyl ester, acetic acid butyl ester, 2-methyl butane and 3-methyl pentane were isolated from takju glutinous rice. 2-Hydroxy-4-methyl pentanoic acid and 2-methyl tridecane were isolated from akju by barley 3-(Methylthio)-1-propanol. hexanoic acid ethyl ester, butanoic acid monomethyl ester, tridecanoic acid, ethyl tetramethyl cyclopentadiene and 1,5-diaza-2,9-diketocyclotetradecane were isolated from takju by wheat flour. Major volatile flavor components were acetic acid ethyl ester, 3-methyl-1-butanol, acetic acid and 2-phenylethanol.

• Korean Journal of Pharmacognosy
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• v.17 no.2
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• pp.178-183
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• 1986

It was our working hypothesis that introduction of 11-keto groups to 12-oleanene/ursene series of triterpenoids should endow them with corticoid-like activities, since pharmacological actions of glycyrrhetinic acid (GA) are known to be caused by inhibition on $corticoid-{\delta}^4-reductase$. 11-Keto-triterpenoids derived artificially in these studies, such as 11, 19-diketo-18, 19-secoursolic acid methyl ester(I), $11-keto-{\beta}-boswellic$ acid derivatives (IIa-IIc), 11-Keto-presenegenin dimethyl ester (III), II-keto-oleanolic acid derivatives (IVa-IVd) and 11-keto-hederagenin (V) possess the fundamental functions of ${\alpha},\;{\beta}-unsaturated$ ketone on C-11 and hydroxyl group on C-3, as like GA (VI). Additionally, they involve the carboxyl groups on rings A (II, III), D (I, III, IV, V) and E (VI), and the hydroxyl groups on rings A (III, V) and C (III). All the compounds competitively inhibited $corticoid-5{\beta}-reductase$, and the highest inhibitory potency appeared in I. All of them except $3,\;11-diketo-{\beta}-boswellic$ acid methyl ester (IIc) were more effective about five times to twice than GA. On carrageenin-induced edema test, compounds I and IVa-IVd showed anti-inflammatory activities, but III enhanced rather edema. Structure-activity relations were found in the aspects of hydrophilicity of ring A and hydrophobicity of rings C/D. The more they were hydrophilic in ring A and hydrophobic in rings C/D, the more they inhibited the enzyme. And the more they were hydrophobic in rings C/D, the more they exhibited antiiflammatory activities. However, the increased hydrophilicity in ring A resulted in increasing edema, probably due to a nonspecific inhibition on $aldosterone-5{\beta}-reductase$.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.322-328
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• 1999

Volatile flavor components of watermelon (Citrullus vulgaris S.) and oriental melon (Cucumis melo L.) obtained by simultaneous steam distillation and extraction apparatus were separated by gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS). Thirty seven and fifty five volatile flavor components were identified in watermelon and oriental melon, respectively. (Z)-3-Nonen-1-ol, (Z,Z)-3,6-nonadien-1-ol, (E,Z)-2,6-nonadienal and (E)-2-nonenal containing unsaturated nine carbon atoms were the characteristic flavor components of watermelon. $C_{9}-Unsaturated$ esters including (Z)-3-nonenyl acetate, (Z)-6-nonenyl acetate, (Z,Z)-3,6-nonadienyl acetate and thioester were important components in the flavor profile of oriental melon.

• Journal of the Korea Furniture Society
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• v.20 no.3
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• pp.198-204
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• 2009

Less used small diameter logs of black locust were heated at $250^{\circ}C$ for improving utilization. The volatile compounds emitted by the heated logs were analyzed. Their effect of formaldehyde absorption was evaluated with PB. Ester and acid compounds were dominant in content. Especially, methyl acetate and acetic acid showed the highest contents. The total content of aromatic compounds decreased as heating time increased. Amoung ketone compounds, The contents of 2-propanone, 2-pentanone, 3-petanone, 3-hexanone and cyclopentenone decreased with the increase of heating time, but the others did not. The contents of the chemicals, furfural and 3-pentanol, increased with heating time, while that of 2-methyl butanal decreased. It was hard to say that formaldehyde was absorbed by the heated black locust samples. Some decorative goods were designed with the heated logs.

• Applied Biological Chemistry
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• v.34 no.4
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• pp.344-352
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• 1991

The whole volatile flavor concentrate obtained from Jindalrae flower was separated into hydrocarbon and oxygen-containing compound(OCC) fractions, and the OCC-fraction was further separated by column chromatography into nine sub-fractions, respectively. These fractions were analyzed by gas chromatography and combined gas chromatography/mass spectroscopy. One hundred and sixty-two components, including 61 hydrocarbons, 18 aldehydes, 18 esters, 41 alcohols, 3 ketones, 4 oxides, 8 acids, 6 phenols and 3 miscellaneous components, were identified.

• Journal of the Korean Chemical Society
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• v.37 no.1
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• pp.68-75
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• 1993

Various biological activities (enzyme inhibitory potency, lipoxygenase inhibition, tadpole narcosis, vapor toxicity and heat of vaporization) of molecules are correlated with molecular descriptors. The molecular descriptors used in this works are molecular connectivity index, Wiener distance index and ad hoc descriptor, which can encode information about branching, size, cyclization, unsaturation, hetero atom content and polarizability. It is found that calculated values from multiple regression equations are in a good agreement with experimental data on five biological activities of alcohol, ester and ketone compounds.

• Bulletin of the Korean Chemical Society
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• v.32 no.10
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• pp.3738-3742
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• 2011

Bismuth tribromide ($BiBr_3$) catalyzed Mannich-type reactions of N-acyliminium ions which generated in situ from N-benzyloxycarbonylamino p-tolylsulfones have been developed. In the presence of catalytic amount of $BiBr_3$, N-benzyloxycarbonylamino p-tolylsulfones prepared from aromatic and aliphatic aldehydes reacted with silyl enol ether and silyl enol ester under mild reaction conditions to afford N-Cbz-protected ${\beta}$-amino ketones and N-Cbz-protected ${\beta}$-amino esters in moderate to good yield, respectively.

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1221-1226
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• 1999

Volatile flavor components of glutinous rice koji kochujang made by an improved method were analyzed by using a purge and trap method during fermentation and identified with GC-MSD. Twenty-one volatile flavor components detected immediately after making kochujang including 6 alcohols, 6 esters and 2 aldehydes. Forty-six volatile flavor components including 15 alcohols, 15 esters, 5 acids, 5 aldehydes, 1 alkane, 1 amine, 1 alkene and 3 others were found in an improved kochujang after 150 day of fermentation. Twenty kinds of flavor components, 5 alcohols such as ethanol, 3-methyl-1-butanol. 2-methyl-1-propanol, 6 ester such as ethyl acetate. 2-methylpropyl acetate, ethylbutanoate, phenylacetate, 2 aldehydes and 7 others were commonly found through the fermentation period. Peak area(%) of ethenone was the highest one among the volatile flavor components at immediately after mashing, and ethyl acetate showed the highest peak area after $30{\sim}60$ day of fermentation, and ethanol showed the highest peak area after $90{\sim}120$ day of fermentation, and 3-methyl-1-butanol showed the highest peak area after 150 day of fermentation(as major components). 2-Methyl-1-propanol, 1-butanol and methylbenzene were detected in glutinous rice koji kochujang during the fermentation.