• Food Science and Preservation
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• v.16 no.1
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• pp.82-86
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• 2009

By analysis of pyruvic acid and sugar levels in bulbs, leaf sheaths, and leaves, and with regard to phyllotaxis, it was shown that the lower portion of each plant component had the greatest pyruvic acid content, the upper portion less, and the middle portion the lowest. When bulb scales were examined, pyruvic acid content was lowest in the second bulb scale from the papery scale. Pyruvic acid level increased toward the inner portion of the bulb. Pyruvic acid levels in leaf sheaths and leaves were greater than those in the bulb during the early stages of bulb growth. However, at harvest, the pyruvic acid content of bulbs increased slightly, whereas those of leaf sheaths and leaves decreased markedly. Tissue sugar contents were similar at the beginning of bulb growth. However, bulb sugar content increased greatly as the bulb grew, and sugar contents of leaf sheaths and leaves decreased. With respect to phyllotaxis, outer older leaves had the lowest total sugar and pyruvic acid contents. Young leaves showed a tendency to have less pyruvic acid and sugar compared with mature leaves.

• Microbiology and Biotechnology Letters
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• v.12 no.4
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• pp.265-270
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• 1984

Luminous marine bacteria which have ability toproduce pyruvic acid were isolated from fresh fishes. Among them, newly isolated bacterium BL-1980 having the highest ability to produce pyruvic acid was selected and identified as Beneckea sp. Optimal conditions for the production of pyruvic acid from glucose by the bacterium BL-1980 were investigated. At the optimal conditions, 10.6g/L of pyruvic acid was produced at the conversion ratio of 35.33%.

• Microbiology and Biotechnology Letters
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• v.15 no.5
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• pp.334-339
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• 1987

Enzymatic conversion of pyruvic acid produced by microorganism to tryptophan was investigated. A luminescent bacteria. Beneckea sp., was used for the production of pyruvic acid. As a source of tryptophanase which synthesizes tryptophan from pyruvic acid, indole and ammonia, whole cells of Enterobacter aerogenes ATCC 10031 were used directly in the reaction mixture. To increase the production of tryptophan, nonionic detergents and nonaqeous organic solvents were used ms reserviors of indole in the reaction mixture. In the case of nonionic detergents, TritonX-100 was very effective. When 1.5% of Triton X-100 was used, 7.7g/$\ell$ of tryptophan was produced at 37$^{\circ}C$ for 48hr. In the case of nonaqueous solvents, 8.7g/$\ell$ of tryptophan was produced at 37$^{\circ}C$ for 48 hr, when 10% of benzene was used. This amount of tryptophan corresponds to conversion of 48% of Indole and 36% of pyruvic acid, respectively.

• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1151-1157
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• 1997

The chemical identities of purified polysaccharide, methylan, were analyzed by various chemical methods. The polysaccharide contained 79%(w/w) sugar, 6% protein, and 16% organic acids such as uronic acid, pyruvic acid, and acetic acid. With proceeding fermentation, the acids content in methylan increased from 10% at 34 hr to 17% at 72 hr, and the viscosity of methylan in the same concentration also increased. The correlation between viscosity and acid content in methylan was studied using chemically or biologically modified methylan. Methylan with a high content of pyruvic acid exhibited a high apparent and an intrinsic ·viscosity. When the pyruvic acid content of methylan with the same content of uronic acid was increased 1%, apparent viscosity and intrinsic viscosity increased 290 cp and 6 dL/g, respectively. Methylan with a high content of uronic acid exhibited a high apparent and an intrinsic viscosity. When the uronic acid content of methylan with the same content of pyruvic acid was increased 1%, apparent viscosity and intrinsic viscosity increased 85 cp and 1.5 dL/g, respectively. It was found that the increased viscosity of methylan resulted from the increased content of organic acids in methylan, and pyruvic acid was more an important factor contributed to the increase of methylan viscosity than uronic acid.

• YAKHAK HOEJI
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• v.29 no.3
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• pp.117-123
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• 1985

A clorimetric determination method of pyruvic acid using hydroxylamine was studied. Hydroxylamine was reacted with pyruvic acid to form complex compound in the presence of Cu(II) ion. Optimal conditions for the quantitative analysis were investigated and the structure of complex was examined spectrometrically. The molar ratio (2:1) and the stability constant ($1.88{\times}10^{4}$) of the complex were measured. It was the characteristic feature of this method that the commonly encountered interfering substances such as fructose, glucose and lactic acid do not infuence the measurement of pyruvic acid.

• Journal of Bio-Environment Control
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• v.17 no.4
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• pp.266-272
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• 2008

The aim of this study was to investigate the effect of supplemental lighting with different lighting intensity during growth on the sugar and pyruvic acid content of onion bulbs. As the result of comparison with growth, the content of pyruvic acid and sugar at harvest, supplemental lightening condition showed better growth, lower pyruvic acid content and higher sugar content than control. As to the growth at harvest according to lightening condition, 'Josaeng-ssundeobol' showed better growth as the lightening increased and 'Damrojunggab' had no difference above $12{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PAR. 'Josaeng-ssundeobol' contained much more content of pyruvic acid and sugar than 'Damrojunggab'. 'Josaeng-ssundeobol' had the lowest pyruvic acid content in $24{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PAR and 'Damrojunggab' had no difference above the $12{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PAR. The sugar content of 'Josaeng-ssundeobol' had no big difference above $18{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PAR and that of 'Damrojunggab' had no big difference above $12{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PAR. Desirable indicator to select individuals for the onion breeding is to select individuals that has low pyruvic acid content and high sweetness. Therefore, it will be possible to produce sweet onion conditioned on light supplement over $18{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PAR in 'Josaeng-ssundeobol' and over $12{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PAR in 'Damrojunggab'.

• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.377-381
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• 2010

This study was carried out to access the stauts of pyruvic acid and sugars in onion bulbs during storage at room temperature. Pyruvic acid content remained in a steady state until 3 months of storage. However the pyruvic acid content gradually increased as the onions started to root, and rapidly increased after sprouting. There was no difference in dry matter contents during storage.e. Sucrose content increased as storage duration extended, and then gradually decreased right after the onions started to sprout. Fructose content gradually decreased after 45 days of storage, and remained in a steady state after sprouting. Glucose content had a tendency to increase as storage duration extended. Pyruvic acid/total sugar (PA/TS) ratio decreased after 1 month of storage, and then increased after 135 days, and was 83% higher at 150 days of storage than at harvest. Sweetness gradually decreased until 1 month of storage, but thereafter remained steady. Therefore it is desirable that pyruvic acid analysis for sweet onion selection should be conducted before breaking the dormancy.

• Applied Biological Chemistry
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• v.24 no.2
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• pp.120-125
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• 1981

Organic acids of Kochuzang (red pepper paste) prepared from glutinous rice, polished barley, wheat flour and sweet potato were analyzed by a gas chromatography. Lactic, pyruvic, succinic, fumaric, malic, pyroglutamic and citric acid were identified. And trace amount of oxalic acid was found in the Kochuzang prepared from sweet potato. The dominant organic acid of all samples was pyroglutamic acid, followed by pyruvic and citric acid. The organic acids were lower in Kochuzang from wheat flour than in other samples. The contents of succinic and fumaric acid were highest in Kochuzang prepared from sweet potato and were lowest in polished barley Kochuzang.

• Journal of Applied Biological Chemistry
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• v.43 no.4
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• pp.269-272
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• 2000

The ginseng growth-promoting bacterium Pseudomonas fluorescens KGPP 207 synthesized indole-3- acetic acid (IAA) from L-tryptophan, indole-3-pyruvic acid (IPyA), and indole-3-acetaldehyde (IAAld), but not from indole-3-acetamide (lAM) and other intermediates of various IAA biosynthetic pathways in the experiment with indole compound supplemented cell suspensions. TLC, HPLC, and GC-MS analyses revealed the presence of IPyA, indole-3-ethanol, indole-3-lactic acid and its methyl ester, IAA and its methyl, and ethyl esters in the culture supernatant of the bacterium. IAAld was detected in the supernatant using sodium bisulfite and TLC. The results indicate that unlike gall-forming bacteria which can synthesize IAA by lAM, the indole-3-pyruvic acid pathway is the route for IAA biosynthesis in this beneficial strain of P. fluorescens.

• Journal of the Korean Chemical Society
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• v.17 no.2
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• pp.136-141
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• 1973

DL-1-aminobutylphosphonic acid was synthesized from the pentanoic acid which was prepared from the butyl alcohol, by the modified Curtius reaction. DL-2-amino-2-carboxyethylphosphonic acid was also synthesized from the pyruvic acid was also synthesized from the pyruvic acid. Four previously unreported N-acylated derivatives were prepared according to the modified Schotten-Baumann method. They are as follows; N-acetyl-DL-1-aminobutylphosphonic acid, N-benzoyl-DL-1-aminobutylphosphonic acid, N-benzoyl-DL-2-amino-2-carboxyethylphosphonic acid, N-p-chlorobenzoyl-DL-2-amino-2-carboxyethylphosphonic acid. The products were identified by the methods of elemental analysis, infrared spectra, ninhydrin test and neutralization equivalent.