• The Korean Journal of Zoology
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• v.33 no.2
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• pp.231-237
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• 1990

Hemicyclops ctenidis sp. n. is descdbed based on the specimens washed from Neanthes laponica collected from Kangreung, South Korea. The new species can be distinguished from its 24 congeners by a combination of features in the segmentation of the first antenna, the structure of the inner sets of the first endopod segment in legs 1-4, and the armature of the second endopod segment in leg 4.

• Korean Journal of Food Science and Technology
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• v.21 no.5
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• pp.662-668
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• 1989

The effect of four different humidities during smokehouse processing on cured color development color intensity, pH, residual nitrite, phenol deposition, TBA value and product yield of Canadian bacon was determined. High humidity resulted in high pigment conversion and lower pH. As the humidity was lowered, more residual nitrite remained, The highest humidity had the highest phenol deposition and TBA value. The lowest humidity had the highest yield.

• Bulletin of the Korean Chemical Society
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• v.9 no.3
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• pp.115-117
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• 1988

The addition of L-cysteine without blocking amino and carboxyl groups to${\beta},{\beta}$-dinitrostyrene derivatives(11a-e) were investigated. ${\beta},{\beta}$ -Dinitrostyrene derivatives(11a-e) easily undergo addition reactions with L-cysteine to from s-(2,2-dinitro-1-phenylethyl)-L-cysteine(12a), s-[2,2-dinitro-1-(p-methyl)phenylethyl]-L-cysteine (12b), s-[2,2-dinitro-1-(p-methoxy)phenylethyl]-L-cystein e(12c), s-[2,2-dinitro-1-(p-chloro)phenylethyl]-L-cysteine (12d) and s-[2,2-dinitro-1-(p-nitro)phenylethyl]-L-cysteine( 12a), respectively. The structure of adducts were confirmed by means of spectral data, molecular weight measurement and elemental analysis.

• Bulletin of the Korean Chemical Society
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• v.10 no.1
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• pp.12-15
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• 1989

Various tertiary amides have been subjected to the reduction by borane-THF in the presence of trimethyl borate at $0^{\circ}C$ and the product ratio of alcohol and amine have been analyzed in order to find out the possible way to obtain one product exclusively on the basis of the structure of amides. In the case of N,N-dimethyl derivatives of both linear aliphatic and aromatic amides the corresponding alcohols were produced predominantly. However, the bulkier tertiary amides such as N,N-diethyl and hindered acid derivatives afforded amines rather than alcohols. The mechanism of borane reduction of tertiary amides is also discussed.

• Bulletin of the Korean Chemical Society
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• v.5 no.6
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• pp.215-218
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• 1984

A series of S-(2,2-diethoxycarbonyl-1-phenylethyl)-L-cysteine derivatives (10a-e) were synthesized from the reaction of $\beta$$\beta$-diethoxycarbonylstyrene with L-cysteine in 1:1 aqueous methanol. Thus, S-(2,2-diethoxycarbonyl-1-phenylethyl)-L-cysteine( 10a), S-[2,2-diethoxycarbonyl-1-(3',4'-methylendioxy)ph enylethyl]-L-cysteine (10b), S-[2,2-diethoxycarbonyl-1-(3',4',5'-trimethoxy)phe nylethyl]-L-cyseine (10c), S-[2,2-diethoxycarbonyl-1-(p-hydroxy)phenylethyl] -L-cysteine (10d), S-[2,2-diethoxycarbonyl-1-(p-methoxy)phenylethyl] -L-cysteine (10e) were obtained in moderate to excellent yields. The structure of the adducts was characterized by analytical and spectral data. The effects of pH upon the product yields were also briefly examined.

• Bulletin of the Korean Chemical Society
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• v.8 no.3
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• pp.162-165
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• 1987

The reduction rate of borohydride exchange resin (BER) was greatly enhanced in the presence of lithium salts. Thus 2-heptanone was reduced completely with BER-LiCl in 1 h at room temperature. However, no reduction was observed with BER alone under the same conditions. With this system, organic compounds containing various fuctional groups were examined in ethanol at room temperature. This study revealed that BER-LiCl system exhibits an excellent chemoselectivity for carbonyl group in the presence of other functional groups. Keto esters and epoxy ketones were reduced with BER-LiCl to give the corresponding hydroxy esters and epoxy alcohols with excellent yields. Selective reductions of carbonyl groups were also possible in the presence of other organic compounds containing functional groups such as 1-idooctane, 1-bromooctane, caproamide, hexanenitrile, nitrobenzene, n-butyl disulfide, dimethyl sulfoxide and 1-dodecene.

• Korean Journal of Food Science and Technology
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• v.24 no.6
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• pp.541-546
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• 1992

In order to develop low salt fermented hen clam sauce with high stability, the effects of citric acid pretreatment and fermentation temperature were examined. The VBN contents of surf clam sauce treated with citric acid (SCA) were lower than those of control and the same sauces added alcohol at two temperature conditions ($5^{\circ}C$ and room temperature) during fermentation. The maximum $NH_2-N$ contents of control and SCA during fermentation at $5^{\circ}C$ were 501.3 and $618.4{\sim}691.6\;mg/100g$, respectively, and the pH of those showed $5.61{\sim}6.24$ and $2.43{\sim}3.21$. The total creatine contents of control and SCA, respectively, were $36.8{\sim}27.6\;mg/100g$ ranges. As the time of treatment with citric acid was longer, the degradation of ATP, ADP and AMP in the SCA was faster. In the control, the Ala content was $19.6{\sim}23.02%$ and was highest level among all free amino acids. As fermenting term was longer, among the free amino acids, Ala and Gly were large amounts in control and SCA, respectively, and Gly was slowly increased in SCA during fermentation. As the results of organoleptic test, the tastes of SCA showed good score than control.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.1
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• pp.33-40
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• 1994

Effects of blanching on protein composition and texture in geoduck muscle during frozen storage at $-20^{\circ}C$ were investigated. In frozen muscle, sarcoplasmic protein and myofibrillar protein were decreased, while alkali-soluble protein increased rapidly. During the storage of the blanched muscle(at $95^{\circ}C$ for 2 min.), sarcoplasmic and myofibrilla protein showed slow decreases. The muscle blanched for 2 min(BM) showed the best texture among the samples treated with various blanching times(at $95^{\circ}C$ for 1, 2, 3, and mins). In comparing the textures of BM with raw muscle, hardness of BM was similar raw muscle, and elasticity and stress relaxation of BM revealed lower levels than those of raw muscle, but break elongation and toughness were higher. In the changes of texture of raw muscle and BM during the frozen storage, as the storage time lengthened, hardness and toughness of both muscles were stronger, and both stress relaxations showed greatly decreases during initial storage(7 days), and break elongation level of raw muscle showed rapid increases in 100 days but there were no changes in that of BM, Elasticity of raw muscle gradually reduced during storage while that of BM increased.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.1
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• pp.1-9
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• 1986

In order to isolate and clarify the antioxygenic substances from the browning reaction products, the antioxidant activity of various amino acids and their browning reaction products were measured when they were reacted with xylose. Among nonpolar amino acids Met and Trp appeared to have stronger antioxidant effect than others. Most of polar and basic amino acids, however, did not have antioxidant activity. Ser and Cys showed a rather slight prooxidant effect. The browning reaction products of Trp and His had a higher level of antioxidant activity than that they were reacted as free amino acids. But the browning product of Met did not show the antioxidant activity. When all amino acids were divided on their polar characteristics, the higher optical density of the browning reaction products showed, the stronger antioxidant activity revealed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.5
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• pp.401-406
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• 1990

In order to assess fish meal as food protein source which contains heat denatured pro-tein, functional properties of fish meal protein to be treated with alkaline were examined. Ratio of fish meal to 0.2N NaOH solution for extract solvent which were 1:10 showed good results of extracted and recovered amount of fish meal protein. pH 4.5, solubility of protein treated with alkaline revealed the lowest value. Until concentrations of alkaline treated protein solution reached $0.7\%$, its emulsifying capacity steeply decreased. Emusifying capacity of alkali treated protein were higher value at pH 9.0 than pH 4.0 and 7.0, and also were higher quantity in 0.5M NaCl solution than that of 0.1M. Heating time of fish meal protein to be treated with alkaline reached until 30 mins, its fat binding capacity indicated little change and that of heating time 60 mins decreased. Gel forming concentrations of fish meal protein to be treated with alkali for 15 mins or less were $20\%$ but those of 30 and 60 mins were $25\%$. When treating time of fish meal protein with alkali solution reached till 20 mins, viscosity of alkali treated protein solution steeply decreased.