• Applied Biological Chemistry
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• v.25 no.3
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• pp.155-160
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• 1982

Claviceps purpurea PRL 1980 produces a fluorescent reddish brown pigment in the alkaloid production medium. When D,L-tryptophan $[side\;chain-3-^{14}C]$ was administered into the production medium, the radioactive pigment and 5-hydroxytryphan were isolated from the cultures. Conversion of tryptophan to 5-hydroxytryptophan in vivo was shown by an isotopic trapping procedure. 5-hydroxytryptophan isolated from the cultures contained appreciable radioactivity and was recrystallized to constant specific radioactivity. The injection of the $^{14}C-labelled$ 5-hydroxytryptophan showed an incorporation of radioactivity into brown pigment significantly higher than that of tryptophan. The brown pigment produced by Claviceps purpurea PRL 1980 seems to be derived from tryptophan through 5-hyrdroxytryptophan.

• Korean Chemical Engineering Research
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• v.44 no.5
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• pp.453-459
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• 2006

D-tryptophan and N-CBZ-D-phenylalanine were separated using ionic liquid as additives for the mobile phase in high performance liquid chromatography (HPLC). The ionic liquid of 1-butyl-3- methylimidazolium tetrafluoroborate (${[BMIm]}^+{[BF_4]}^-$) was used. Mobile phases were 65％, 70％, and 80％ methanol in water with addition of different concentrations (0.5, 1.0, 1.5, 2.0, 4.0, 6.0, 8.0, 10.0, 12.0, and 15.0 mmol/L) of the ionic liquid. The experiments were performed on stainless steel column, $3.9{\times}300mm$ i.d., packed with $15{\mu}m$ octadecyl-bonded silica gel at laboratory.The retention factor of D-tryptophan was not negligibly changed while that of N-CBZ-D-phenylalanine was decreased. The resolution between the two components were affected by the contents of methanol and ionic liquid in the mobile phase. With the small content of methanol and the high concentration of ionic liquid, the resolution was improved.

• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3367-3371
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• 2011

An easy and convenient synthetic route to (S)-2-hydroxy-2'-(3-phenyluryl-benzyl)-1,1'-binaphthyl-3-carboxaldehyde (1), capable of recognizing tryptophan by fluorescence has been developed. The binol carboxaldehyde 1 exhibited a high selectivity to L-tryptophan over other examined L-${\alpha}$-amino acids such as alanine, phenylalanine, glutamine, arginine, lysine, serine, threonine, aspartat, valine, histidine and cysteine, with a fluorescence "turn-on" signal. In addition, 1 displayed chiral discrimination with good enantioselectivity toward L-tryptophan over D-tryptophan through different fluorescence enhancement factors.

• Journal of the Korean Home Economics Association
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• v.30 no.4
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• pp.89-105
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• 1992

The purpose of this study was to see the effect of oral administration of reserpine (2mg/d) and tryptophan (40.35mg/d) on the serum amino acid concentrations and organ composition, food consumption, body weight, blood hematocrit(Hct) and hemoglobin(Hb) levels in Sprague-Dawley rats fed 6% or 20% casein diet. Any adverse effects of reserpine and tryptophan were not observed in animals, except that liver fat contents were increased in low protein group. In other words the administration of typtophan decreased liver fat contents in 6% casein and reserpine-treated 20% casein groups, but increased in reserpine-treated 6% casein group. But the low protein diet had significant adverse effects in animals. The 6% casein diet, therefore, had a tendency to decrease food consumption and body weight. The simillar tendency was shown in serum essential amino acid concentrations, organ weight and protein contents of liver and muscle. From the results, it would be safe to conclude that the oral administration of large deses of reserpine and tryptophan did not induce such a signifcant malnutrition as the low protein diet did.

• Journal of Plant Biotechnology
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• v.42 no.3
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• pp.186-195
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• 2015

Anthranilate synthase (AS) is a key enzyme in the biosynthesis of tryptophan (Trp), which is the precursor of bioactive metabolites like indole-3-acetic acid and other indole alkaloids. Alpha anthranilate synthase 2 (OsASA2) plays a critical role in the feedback inhibition of tryptophan biosynthesis. In this study, two vectors with single (F124V) and double (S126F/L530D) point mutations of the OsASA2 gene for feedback-insensitive ${\alpha}$ subunit of rice anthranilate synthase were constructed and transformed into wildtype Dongjinbyeo by Agrobacterium-mediated transformation. Transgenic single and double mutant lines were selected as a single copy using TaqMan PCR utilized nos gene probe. To select intergenic lines, the flanking sequence of RB or LB was digested with a BfaI enzyme. Four intergenic lines were selected using a flanking sequence tagged (FST) analysis. Expression in rice (Oryza sativa L.) of the transgenes resulted in the accumulation of tryptophan (Trp), indole-3-acetonitrile (IAN), and indole-3-acetic acid (IAA) in leaves and tryptophan content as a free amino acid in seeds also increased up to 30 times relative to the wildtype. Two homozygous event lines, S-TG1 and D-TG1, were selected for characterization of agronomic traits and metabolite profiling of seeds. Differentially expressed genes (DEGs), related to ion transfer and nutrient supply, were upregulated and DEGs related to co-enzymes that work as functional genes were down regulated. These results suggest that two homozygous event lines may prove effective for the breeding of crops with an increased level of free tryptophan content.

• Journal of the Korean Applied Science and Technology
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• v.32 no.3
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• pp.451-460
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• 2015

An enantioselective recognition of D- and L-tryptophan (Trp)-b-cyclodextrin (CD) inclusion complex was performed using electrochemical and FT-Raman spectroscopic analysis. From the electrochemical analysis, the selectivity coefficient ($K_{DL}$) of b-CD inclusion complexes was found higher than that of the D- and L-Trp in phosphate buffered saline (PBS, pH=7.0) solution. The percentage of enantioselectivity ($I_{%{ee}}$) for peak current of D-Trp-b-CD inclusion complexes was observed higher than that of L-Trp-b-CD inclusion complexes in PBS solution. From Raman spectroscopy, chemical shift difference (D, $cm^{-1}$) for the C=C stretch, ring vibration, and ring breathing of D-Try-b-CD inclusion complex were observed higher than that of L-Trp-b-CD inclusion complex. The electrochemical and Raman spectroscopic analyses were found very useful for chiral detection of racemic amino acid in the presence of b-CD.

• KSBB Journal
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• v.4 no.3
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• pp.288-292
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• 1989

Induction and culture of hairy roots from ginseng(Panax ginseng C. A. Meyer) roots discs by A. rhizogenes strain $A_4$ were studied. After 6-12 weeks infected with A. rhizogenes tumor and hairy roots emerged from the root discs. The ratio of hairy root induction on root discs was higher in 5-year old than in 3, 4, and 6-year old ginseng. On treatment with IAA, IBA, 2, 4-D and tryptophan, hairy roots formation showed a significant increase at 15-30mg/1 tryptophan treated. Subsequently, hairy roots were cultured on hormone-free RCM medium(pH 4.5, sucrose 30g/1).

• Journal of Microbiology and Biotechnology
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• v.10 no.6
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• pp.789-796
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• 2000

In order to analyze the effects of tktA, $aroF^{FBR}$, and aroL expression in a tryptophan-producing Escherichia coli, a series of plasmids carrying the genes were constructed. Introduction of tktA, $aroF^{FBR}$, and aroL into the E. coli strain resulted in approximately 10-20 fold increase in the activities of transketolase, the feedback inhibition-resistant 3-deoxy-D-arabinoheptulsonate-7-phosphate synthase, and shikimate kinase. Expression of $aroF^{FBR}$ in the aroB mutant strain of E. coli resulted in the accumulation of 10 mM of 3-deoxy-D-arabinoheptulsonate-7-phosphate (DAHP) in the medium. Simultaneous expression of tktA and $aroF^{FBR}$ in the strain further increased the amount of excreted DAHP to 20 mM. In contrast, the mutant strain which has no gene introduced accumulated 0.5 mM of DAHP. However, the expression of tktA and $aroF^{FBR}$ in a tryptophan-producing E. coli strain did not lead to the increased production of tryptophan, but instead, a significant amount of shikimate, which is an intermediate in the tryptophan biosynthetic pathway, was excreted to the growth medium. Despite the fact that additional expression of shikimate kinase in the strain could possibly remove 90% of excreted shikimate to 0.1 mM, the amount of tryptophan produced was still unchanged. Removing shikimate using a cloned aroL gene caused the excretion of glutamate, which suggests disturbed central carbon metabolism. However, when cultivated in a complex medium, the strain expressing tktA, $aroF^{FBR}$, and aroL produced more tryptophan than the parental strain. These data indicate that additional rate-limiting steps are present in the tryptophan biosynthetic pathway, and the carbon flow to the terminal pathway is strictly regulated. Expressing tktA in E. coli cells appeared to impose a great metabolic burden to the cells as evidenced by retarded cell growth in the defined medium. Recombinant E. coli strains harboring plasmids which carry the tktA gene showed a tendency to segregate their plasmids almost completely within 24h.

• Toxicological Research
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• v.3 no.1
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• pp.9-14
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• 1987

The effects of monosodium glutamate (MSG) on the activities if tyrosine hydroxylase (TH), dopamine ${\beta}$-hydroxylase (DBH), tryptophan hydroxylase (TPH) and monoamine oxidase (MAO) in various regions (cerebral cortex, striatum, midbrain, pons and medulla of nat brain have been determined. It was observed that up to 1mM MSGhad no significant effects on the activities of brain tyrosine hydroxylase, dopamine ${\beta}$-hydroxylase, tryptophan hydroxylase and monoamine oxidase in all regions of rat brain. These results indicated that MSG itself exerted no direct effect on the important enzymes synthsizing and metabolizing the monoaminergic neuronal system.

• Korean Chemical Engineering Research
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• v.48 no.4
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• pp.515-518
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• 2010

D,L-tryptophans were separated by using $Chirobiotic^{(R)}$ T HPLC column. Mobile phases were the mixture of methanol and water(70:30, 80:20, 90:10, v/v). Experimental temperatures were adjusted as 25, 40 and $55^{\circ}C$ in order to compare retention times. Difference in D,L-tryptophan retention times was studied in terms of the interaction between stationary phase and tryptophans. Selectivity, resolution and efficiency of column were utilized to find an optimum separation condition. Retention times were shortened by increasing the amount of methanol in mobile phase and the temperature of column. The best selectivity and resolution was obtained with the temperature($25^{\circ}C$) and the ratio of mobilephase(70/30 v/v%).