• Korean Journal of Food Science and Technology
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• v.18 no.6
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• pp.492-496
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• 1986

A compound stimulatory to the growth of S. thermophilus CH-1 was isolated from the cell-free filtrate of L. helveticus YM-1 in milk medium. The stimulant was identified as a peptide with a molecular weight of approximately 5000 and exhibited positive ninhydrin reaction. Some kinds of amino acids confirmed as aspartic acid, alanine, valine, glutamic acid, lysine, proline, leucine were rich in the stimulatory peptide hydrolysate. Among them, glutamic acid was most abundant. Judging from bioautographic results, glutamic acid and phenylalanine were expected to exert an important role for the stimulation.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.20 no.1
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• pp.37-51
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• 1994

Empty cross-linked chitosan microcapsule was prepared by chemical cross-linking reaction using glutaraldehyde(GA). Chitosan bead was also prepared by coacervation method using sodium hydroxide. The technique involves the formation of a chitosan solution in the discontinuous phase of W/O emulsion. The factors influencing the emulsion stability have been examined to establish optimum conditions Chitosan microcapsules were useful for encapsulation of biological materials, and chitosan bead was useful to prepare the biologically active peptide-bound polysaccharide. As a model compound Gly-His-Lys, cell growth factor, was successfully coupled to chitosan bead.

• Journal of Plant Biology
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• v.20 no.2
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• pp.83-89
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• 1977

Changes in the alcohol-soluble free amino acids during germination of a spring grain, Wanju and two winter grains, Sedohadaka and Nonsankwa No.1-6 which are differing in their degree of spring (winter) habits, were investigated by thin layer chromatography. The results obtained are as follows. 1. Throughout the germination period, 25 ninhydrin positive components; 22 amino acids including two amides and 3 unknown spots were detected. It is interesting to note that identification of histidine was confined to Wanju and Sedohadaka but Nonsankwa No.1-6, which has the lower degree of spring habit. 2. Except the quiescent seeds, the major components were generally composed of the acidic and neutral amino acids together with glutamine and asparagine. 3. Proline was contained in higher quantity except from the stage of quiescent seeds, but the outstanding difference among the varieties was not recognized. Whether this component is related to the mechanism of spring habit in barley or not is a problem to be studied more. 4. In all the varieties, most of the changes in amino acid levels during germination were usually in the same direction and of the same pattern under the temperature controlled not to be varnalized. In view of the results above, the changes in the amino acid levels seem to be more affected by the changes of growing circumstances and the subsequent metabolic activities of certain enzymes than by the characteristics of varieties themselves.

• Preventive Nutrition and Food Science
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• v.15 no.2
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• pp.120-129
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• 2010

To elucidate the composition of extractive nitrogenous components in the fresh Capsosiphons fulvescens cultured off the southern coast of Korea, and to determine the monthly variation of these nitrogenous components, extract samples collected monthly from December to March at Jangheung-gun, Jeonnam Province were analyzed for total nitrogen, free and combined amino acids, ATP and related compounds, betaines, trimethylamine oxide (TMAO) and trimethylamine (TMA). The content of extractive nitrogen was 1,090~1,233 mg/100 g on dry basis. The number of 21~25 ninhydrin-positive substances was detected in the analysis of free amino acids, and their total amount was 3,710~4,788 mg/100 g on dry basis. Among them, free proline, asparagine, glutamic acid, alanine, taurine and glutamine were found to be abundant. The combined amino acids amounted to 1,573~2,121 mg/100 g in total and the total amount of ATP and related compound was 33.8~84.0 mg/100 g ($1.06{\sim}2.46\;{\mu}mol/g$) on dry basis. Betaine, glycinebetaine, $\beta$-alaninebetaine, $\gamma$-butyrobetaine, homarine and trigonelline were detected in most of samples. Levels of free and combined amino acids, ATP and related compounds fluctuated from sample to sample, with their contents higher in December and January and lower in March.

• Korean Journal of Food Science and Technology
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• v.1 no.1
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• pp.78-84
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• 1969

An attempt has been made to investigate the possible occurrence of aflatoxins, a group of micotoxin which are toxic metabolites produced by Aspergillus flavus, and aflatoxin like substances in fungal fermented soybean products such as meju and soybean paste. Chloroform extracts from 15 samples which has been defated with petroleum ether are subjected to separations with thin-layer chromatography on silica gel washed with methanol prior to film coating, improves the chromatographic separation and ultraviolet absorption spectral identification. In addition to fluorescencing spot having an Rf value which is same as aflatoxin $B_1$, many of the fluorescencing spots have been occurred in every sample examined. Each fluorescencing spot is scratched and the ethanol extracts are subjected to further separation with thin-layer chromatography. Each fluorescence substance is eluted with ultra violet transparent absolute ethanol and the ultraviolet absorption spectra are checked. None of the absorption curve of eluates shsow accordance with the curve of aflatoxin. 2, 4-Dinitrophenyl hydrazine reagent, Tollen's reagent and ninhydrin reagent are applied on the chromatogram- The data show that aflatoxin is not present in any of the fungal preparations examined.

• Korean Journal of Food Science and Technology
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• v.1 no.1
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• pp.74-77
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• 1969

In this study, three kinds of Korean snake wine (50 V% alcohol extracts) were determined by amino acid analyzer and were discussed as follows. 1. Salmosa Ju and Nungsa Ju were composed of 22 free amino acids: cysteic acid, aspartic acid, threonine, serine, glutamic acid, proline, glycine, alanine, cystine, valine, methionine, iso-leucine, allo-iso-leucine, leucine, nor-leucine, tyrosine, phenylalanine, ${\beta}-alanine$, lysine, arginine, histidine, trytophan. 2. Doksa Ju were composed of 21 free amino acids which were all same as above except missing histidine. 3. The free amino acid composition were almost identical in Doksa Ju, Salmosa Ju and Nungsa Ju quantitatively. 4. The contents of cysteic acid, glutamic acid, glycine, alanine, valine, leucine and lysine were relatively high, on the other hand, methionine, allo-iso-leucine, nor-leucine, and tryptophan were trace amount in every snake wine. 5. Eleven unknowns of ninhydrin positives were identified in the every snake wine. 6. The free amino acids in snake wines were various in kind as compared with in beer, Japanese sake and Korean Tack Ju. Especially cysteic acid, allo-iso-leucine, nor-leucine and ${\beta}-alanine$ in snake wines were missed in every cereal wine.

• Journal of the Korean Chemical Society
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• v.19 no.2
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• pp.134-141
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• 1975

DL-1-aminoethylphosphonic acid(1-AEP) and DL-1-aminopropylphosphonic acid(1-APP) were synthesized from the propionic acid and butyric acid respectively using the modified cutius degradation. The following unreported derivatives containing peptide linkage were synthesized: N-phthalylglycyl-1-AEP, N-phthalyl-dl-alanyl-1-AEP, N-phthalyl-dl-phenylalanyl-1-AEP, N-phthalylglycyl-1-APP, N-tosylglycyl-1-AEP and N-tosyl-dl-alanyl-1-AEP These compounds were characterized and identified by means of elemental analysis, potentiometric titration, infrared spectroscopy and ninhydrin test.

• Journal of the Korean Chemical Society
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• v.5 no.1
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• pp.9-14
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• 1961

Ethanol extracts of Mung Bean seeds and seedings were analysed by 2-dimensional and circular paper partion chromatography for Nitrogen compounds as a part of the study on the Amino acids metabolism. In the seeds, 18 ninhydrin positive substances were present, before germination, but the number increased to 21 after germination. There were 3 unknown substances and one of it formed newly after germination. After 2-days germination, the amount of amides, such as Asparagine and Glutamine. where increased very large which were very small amount before it. Those were accumulated more in dark place than in light and the amount of Asparigine were more than that of Glutamine. Through the germination, there were large amount of Glutarmic acid, Aspartic acid and Alanine which seems to be concerned in transamination reaction in seedings. Valine, Leucine, and Phenylalanine increased to considerable amount after germination. This is very remarkable fact as those Amino acids were reported to be concerned in transamination reaction recently. ${\gamma}$-amino butyric acid was detected in both Cotyledon and Embroy through the germination. It seemed that there is no any Nitrogen Metabolism in the unbroken seed even if it is preserved very long period.

• Journal of the Korean Chemical Society
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• v.8 no.2
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• pp.85-87
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• 1964

In order to stabilze alloxan as a reagent for detection of amino acids by spot test, sugars and other reductants were added to the aqueous alloxan solution. It was found that lactose was the best for the purpose. The alloxan reagent containing lactose did not give color change on blank test and was very stable that there was no color change even it was allowed to stand in room temperature for several months. The color reaction with amino acids and some amines was not affected by lactose. This spot test for amino acids is in sensitivity as comparable to that of the previously reported methods and gave color reaction with proline and hydroxyproline to 1${\gamma}$ and 5${\gamma}$ respectively.

• Korean Journal of Microbiology
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• v.21 no.4
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• pp.207-212
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• 1983

Isolated Gram-negative bacteria, being capable of degrading toxic, recalcitrant, and pigment-producing furfural, were tentatively identified as Pseudomonas testosteroni, Pseudomonas maltophilia, Klebsiella Pneumoniae, and Pseudomonas fluorescens. They exhibited synergistic effects between P. testosteroni and the others in the degradation of colourproducing furfural. Synergistic effects and possible sequence of its degradation were attempted by manometric technique. P. testosteroni could degrade furfural to decolourize it and produce ninhydrin-reaction postive substance (NPS) which could be utilized by P. maltophilia and K. pneumoniae and the latter two bacteria could ,degrade furfural to 2-furoic acid as an oxidized form. Finally 2-furoic acid was further oxidized by P. fluorescens. Once NPS and 2-furoic acid were produced, the degradation efficiency was enhanced by competing four bacteria against furfural and 2-furoic acid.