• The Korean Journal of Food And Nutrition
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• v.25 no.3
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• pp.677-684
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• 2012

A bacterium strain GS-2 isolated from the Korean traditional seasoning food, Chungkookjang and was determined to produce large amounts of ${\gamma}$-PGA with high productivity when provided with simple nutrients (L-glutamic acid 2.0%, glucose 1.0%, $NH_4Cl$ 0.5%, $KH_2PO_4$ 0.05%, $MgSO_4{\cdot}7H_2O$ 0.01%, pH 7.0). In this study, the culture medium for this strain was optimized for the production of ${\gamma}$-PGA. The Bacillus subtilis GS-2 required supplementation with L-glutamic acid and other nutrients for maximal production of ${\gamma}$-PGA. The optimal culture conditions for ${\gamma}$-PGA production were a 48 hr culture time, a temperature of $33^{\circ}C$ and initial pH of 6.5 by rotary shaking (220 rpm). A maximum ${\gamma}$-PGA production of 31.0 $g/{\ell}$ was obtained with L-glutamic acid (30 $g/{\ell}$), sucrose (the main carbon source, 30 $g/{\ell}$), $NH_4Cl$ (the main nitrogen source, 2.5 $g/{\ell}$), $KH_2PO_4$ (1.5 $g/{\ell}$) and $MgSO_4{\cdot}7H_2O$ (0.15 $g/{\ell}$) in the culture medium.

• Journal of Microbiology and Biotechnology
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• v.11 no.5
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• pp.798-803
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• 2001

Peptide synthetases produced from various microorganisms are multifunctional enzyme complexes and their substrates are recognized and activated by adenylation domains. To identify the substrate specificity of the peptide synthetase isolated from Bacillus subtilis 713, known to produce an antifungal peptide, two adenylation domains containing the minimal functional portion were expressed and purified. ATP-ppi exchange experiments and kinetic studies revealed that the two adenylation enzymes had a substrate specificity to $_{L}-lysine{\;}and{\;}_{L}-tryptophan$, respectively. In addition, based on a signature sequence comparison, the substrate of the third domain was predicted to be L-glutamic acid. These results suggest that this peptide synthetase is novel because there has been no previous report on a peptide synthetase that uses $_{L}-lysine,{\;}_{L}-tryptophan,{\;}and{\;}_{L}-glutamic$ acid as substrates in that order.

• The Korean Journal of Food And Nutrition
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• v.12 no.4
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• pp.421-426
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• 1999

The major flavor compounds of Takju mash which was brewed with a modified Nuruk made by inocu-lation and cultivation of Rhizopus japonicus T2, Aspergillus oryzae L2 and Hansenula sp. BC26 isolated from Nuruk, were analyzed, as compared with those with current fermenting agents such as commerical Nur-uk and rice koji of Aspergillus kawachii. The contents of isoamyl alcohol isobutyl alcohol and ethyl acet-ate which were known as aroma compounds in Takju were much higher in mash of modified Nuruk than in that of commercial Nuruk or ricd koji. The major organic acids were lactic fumalic and succinic acid in mash of modified and lactic and acetic acid in mash of commercial Nuruk and citric lactic and suc-cinic acid in mash of rice koji. The contents of total organic acids were 5,146mg/L, 1,706mg/L and 1, 388 mg/L in mash of commercial Nuruk rice koji and modified Nuruk respectively. The major free amino acids were glutamic acid alanine proline and histidine in mash of modified Nuruk and glutamic acid proline leucine and histidine in mash of commercial Nuruk and arginine proline and glutamic acid in mash of rice koji. The contents of total free amino acids were 14,090mg/L 12,202mg/L and 7,152 mg/L in mash of modified Nuruk commercial Nurcuk and rice koji respectively. Therefore it seemed that the Takju mash of modified Nuruk was better than that of commercial Nuruk or rice koji.

• Microbiology and Biotechnology Letters
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• v.1 no.2
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• pp.105-113
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• 1973

The effect of biotin and biotin vitamer on the fermentative production of L-glutamic acid (L-GA) by Brevibacterium flavum was studied. And results were as follows. 1) L-GA production in the medium containing 10％ Glucose was the best at the concentration of Biotin 5${\gamma}$/l, Desthiobiotin 5${\gamma}$/1, and 7,8-Diaminopelargonic acid 10${\gamma}$/1, respectively. 2) In the experiment using the Glucose-Acetate mixed media derided into four parts, considerable amounts of cell growth and L-GA production were observed in the mixed medium containing 2％ Glucose-Acetate. 3) In the cases of using the media containing methanol, ethanol, ethylacetate, acetic acid (free acetate), Na-acetate:NH$_4$-acetate=2 : 1, the production of L-GA were in decreasing order as follows; Na-Acetate:NH-Acetate=2 : 1> Acetic acid (free acetate)> Ethylacetate> Ethanol＞ Methanol. 4) When biotin vitamers as growth factors were added in the medium containing Glucose or Acetate as the source of carbon, the substitution effect of Desthiobiotin was almost the same, 7,8-Diaminopelargonic acid 3 or 4 times stronger, and Bisnorbiotin has no substitution effect, compared with Biotin.

• Journal of the Korean Chemical Society
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• v.33 no.5
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• pp.504-509
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• 1989

Cobalt(III) complexes of N,N'-dimethylethylenediamine-N,N'-di-${\alpha}$-butyric acid(dmedba) and trifunctional aminoacids, [Co(dmedba)(L-aa)] (L-aa = S-methyl-L-cysteine, L-methionine, L-glutamic acid, L-aspartic acid) have been prepared from the reaction between the $ s-cis-[Co(dmedba)Cl_2]-^$ complex and the amino acid. The amino acids have been found to coordinate through the amine and carboxylate groups just like [Co(dmedda)(L-aa)]. The complexes obtained in this work were characterized by their proton magnetic resonance, infrared and visible absorption spectral data along with the elemental analyses.

• Bulletin of the Korean Chemical Society
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• v.17 no.5
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• pp.433-436
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• 1996

Cobalt(Ⅲ) complexes of trifunctional amino acid and N,N'-diethylethylenediamine-N,N'-di-α-butyrate(deedba), s-cis-[Co(deedba)(L-aa)] (L-aa=S-methyl-L-cysteine, L-aspartic acid, L-glutamic acid) have been prepared from the reaction between the s-cis-[Co(deedba)(Cl2)]- complex and the corresponding amino acid. The amino acids have been found to coordinate through the amine and carboxylate groups. The S-methyl-L-cystene is coordinated not by the sulfur donor atom, but by the nitrogen and oxgen donor atoms, and the L-aspartic and L-glutamic acids are coordinated to the cobalt(Ⅲ) ion via formation of the five-membered glycinate chelate ring. Relatively small optical activity shown by the complexes is due to the chiral center present in the amino acids.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.4
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• pp.289-295
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• 2005

In this study, the cultural medium used for the efficient production of $\gamma$-PGA with a newly isolated Bacillus sp. RKY3 was optimized. It was necessary to supplement the culture medium with L-glutamic acid and an additional carbon source in order to induce the effective production of $\gamma$-PGA. The amount of $\gamma$-PGA increased with the addition of L-glutamic acid to the medium. The addition of 90 g/L L-glutamic acid to the medium resulted in the maximal yield of $\gamma$-PGA (83.2 g/L). The optimum nitrogen source was determined to be peptone, but corn steep liquor, a cheap nutrient, was also found to be effective for $\gamma$-PGA production. Both the $\gamma$-PGA production and cell growth increased rapidly with the addition of small amounts of $K_2HPO_4$ and $MgSO_4\cdot7H_{2}O$. Bacillus sp. RKY3 appears to require $Mg^{2+}$, rather than $Mn^{2+}$, for $\gamma$-PGA production, which is distinct from the production protocols associated with other, previously reported bacteria. Bacillus sp. RKY3 may also have contributed some minor $\gamma$-PGA depolymerase activity, resulting in the reduction of the molecular weight of the produced $\gamma$-PGA at the end of fermentation.

• Polymer(Korea)
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• v.24 no.6
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• pp.802-809
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• 2000

Counterion-specific helix formation and ion-selective transport of alkali metal chlorides (LiCl, NaCl, KCl, CsCl) were investigated for a poly(L-glutamic acid)(PLGA)/poly (vinyl alcohol)(PVA) blend membrane immersed in aqueous ethanol. The counterion specificity for helix formation of PLG alkali metal salts in the membrane was Li>Na>K>Cs. This specificity is ascribed to a contact ion-pair formation between the PLG carboxyl anion and the bound counterion, which depends on the energy balance between the electrostatic interaction and the desolvation. In aqueous ethanol, an appreciable ion-selectivity was observed for the permeability coefficient, i.e. Li$^{+}{\cdot}$Cl$^{-}$) formation between counterion and coion, and the latter to a specific interaction of diffusing counterions with polymer charges.

• Journal of the Korean Wood Science and Technology
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• v.31 no.6
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• pp.60-66
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• 2003

Mycelial growth of L. edodes by supplement nutrition of softwood was studied on a sawdust medium. The sawdust used was from the following softwood species : Larix leptolepis, Pinus densiflora and Pinus koraiensis. The added nutritions consisted of carbon nutritions(sucrose, active carbon, xylose, glucose, paper pellet), nitrogen nutritions(potassium nitrate, ammonium chloride, asparagine, glutamic acid) and vegetable oil(rice bran oil). The sawdust medium was a mixture of 76% sawdust, 20% rice bran, 3% carbon nutrition, 0.4% nitrogen nutrition and 0.6% calcium carbonate. Following addition of carbon and nitrogen nutritions on the sawdust medium proved most suitable : L. leptolepis (glucose, glutamic acid), P. densiflora (active carbon, asparagine) and P. koraiensis (xylose, glutamic acid). The highest mycelial growth was obtained from sawdust medium of optimum condition with 97% of L. leptolepis, 110% of P. densiflora and 98% of P. koraiensis. This study has provided useful preliminary information for the cultivation of L. edodes.

• Korean Journal of Microbiology
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• v.53 no.2
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• pp.97-102
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• 2017

Catechol type siderophore different from 2, 3-dihydroxybenzoic acid (DHB) was produced from Acinetobacter sp. B-W grown in medium containing L-glutamic acid as both carbon and nitrogen sole sources at $28^{\circ}C$. Optimal concentration of glutamic acid for siderophore production was 3% and production of siderophore was decreased above 3% glutamic acid. In previous report, siderophore, 2, 3-DHB was produced from strain B-W grown in medium containing glucose as carbon source and glutamic acid as nitrogen source. Rf value of siderophore produced from strain B-W grown in medium glutamic acid as both carbon and nitrogen sole sources at $28^{\circ}C$ was 0.32, while 2, 3-DHB was 0.84 in butanol-acetic acid-water (12:3:5) as developing solvent. Antioxidative activity of 2, 3-DHB was not detected in that siderophore produced from glutamic acid. Catechol nature of siderophore was detected by Arnow test. Although in iron-limited media optimal cell growth was identified at $36^{\circ}C$, significant quantities of siderophore were produced only at $28^{\circ}C$. Biosynthesis of siderophore was strongly inhibited by growth at $36^{\circ}C$. Production of siderophore was completely inhibited by $10{\mu}M\;FeCl_3$.