• Microbiology and Biotechnology Letters
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• v.22 no.5
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• pp.557-560
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• 1994

The optimum medium composition for the production of L-tryptophan with Klebsiella pnuemoniae pheA tyrA trpE trpR/pSC 101-trp$^{+}$ and the effect of precusors in the optimum medium were studied. The specific growth rate in the optimum medium was almost the same as that in the basal medium, the former showing 1.01 and the latter 1.07 hr $$^{-1}$, but the produced tryptophan was increased 45% in the optimum medium. The maximum amount of produced tryptophan was 159 mg/l within 14 hours. Tryptophan production was ceased by casamino acid addition over 4 g/l in medium, but cell maSS increased with its addition. Indole and anthranilate as precusors had toxic effect on growth and tryptophan production at experimented concentration range (over 20 mg/l), but L-serine had good effect on tryptophan production, resulting in 175 mg/l tryptophan within 14 hours.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.5
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• pp.775-781
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• 2002

The T-type amino acid transporter 1 (TATI) is a Na$^{+}$-independent amino acid transporter which selectively trans- ports aromatic amino acids subserving the amino acid transport system T. To understand the transport properties of aromatic amino acids by human TAT1 (hTATl ), we have examined the hTATl -mediated aromatic amino acid transports using a Xenopus laeuis oocyte expression system. When expressed in Xenopin laeuis oocytes, hTATl induced L- [$^{14}$ C]tryptophan transport which was not dependent on Na$^{+}$ or Cl$^{[-10]}$ in the medium. Uptake was time-dependent and exhibited a linear dependence on incubation time up to 30 min. The L- ($^{14}$ C)tryptophan uptake was highly inhibited by L-isomers of tryptophan, tyrosine and phenylalanine, whereas other L-amino acids did not inhibit hTATl -mediated L- ($^{14}$ C)tryptophan uptake. The hTATl induced the relatively low-affinity transport of aromatic amino acids such as L- ($^{14}$ C)tryptophan, L- ($^{14}$ C)tyrosine and L- ($^{14}$ C)phenylalanine (Km values: 450～750 $\mu$M), consistent with the properties of classical amino acid transport system T. The L- ($^{14}$ C)tryptophan uptake did not show any remarkable pH dependence within the pH range of 5.5 to 8.5. The time-dependent efflux of L- ($^{14}$ C)tryptophan was detected from the oocytes expressing hTATl, which was not affected by the presence or absence of L-tryptophan in the extracellular medium, indicating that hTATl-mediated transport is due to the facilitated diffusion. Expression of hTATl in Xenopu laevis oocytes induced the transport of tryptophan, tyrosine and phenylalanine, indicating that hTATl is a transporter subserving system T These results suggest that hTATl has essential roles in the absorption of aromatic amino acids from epithelial cells to the blood stream. Hecause hTATl is proposed to be crucial to the efficient absorption of aromatic amino acids from intestine and kidney, its defect such as blue diaper syndrome could be involved in the disruption of aromatic amino acid transport.ort.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.8
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• pp.1202-1208
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• 2015

The effects of daily dietary Bacillus subtilis (Bs), and adding L-tryptophan, fructan, or casein to fecal fermentation broths were investigated as means to reduce the production of noxious gas during manure fermentation caused by ammonia, hydrogen sulfide ($H_2S$), and 3-methylindole (skatole). Eighty swine ($50.0{\pm}0.5kg$) were equally apportioned to an experimental group given Bs in daily feed, or a control group without Bs. After 6 weeks, fresh manure was collected from both groups for fermentation studies using a $3{\times}3$ orthogonal array, in which tryptophan, casein, and fructan were added at various concentrations. After fermentation, the ammonia, $H_2S$, L-tryptophan, skatole, and microflora were measured. In both groups, L-tryptophan was the principle additive increasing skatole production, with significant correlation (r = 0.9992). L-tryptophan had no effect on the production of ammonia, $H_2S$, or skatole in animals fed Bs. In both groups, fructan was the principle additive that reduced $H_2S$ production (r = 0.9981). Fructan and Bs significantly interacted in $H_2S$ production (p = 0.014). Casein was the principle additive affecting the concentration of ammonia, only in the control group. Casein and Bs significantly interacted in ammonia production (p = 0.039). The predominant bacteria were Bacillus spp. CWBI B1434 (26%) in the control group, and Streptococcus alactolyticus AF201899 (36%) in the experimental group. In summary, daily dietary Bs reduced ammonia production during fecal fermentation. Lessening L-tryptophan and increasing fructan in the fermentation broth reduced skatole and $H_2S$.

• 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.

• 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 Journal of Poultry Science
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• v.17 no.4
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• pp.303-309
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• 1990

In order to study the effect of diet supplemented with 0.015% (150ppm) of L-tryptophan on the performance of broiler breeder, the performance of parent stock of 1768 breeder(Hubbard) fed on the diet supplemented with L tryptophan was compared with those of 1105 breeders fed on the basal (control) diet Henday egg and settable egg production, fertility, hatchability and number of quality chicks per settable egg were recorded during 133 days(34－52 week－old) of experimental feeding period. Also during 28 days of after experimental feeding period(53－56 week－old) the henday egg and settable egg production were recorded. The henday egg production of breeder fed L-tryptophan was similar with that fed the control diet during 7 weeks of the peak laying period(34－41 week－old) after beginning of the experimental feeding but which was significantly(P＜0.05) higher during 84 days of the post peak laying period(41－52 week－old) and 28 days of after experimental feeding period(53－56 week－old) than those of control And birds fed the L-tryptophan layed significantly (P＜0.01) higher numbers of the sellable eggs than those fed control diet during the post peak laying and after experimental feeding periods. While the coefficient of variance for the henday egg and settable egg production were shown lower values in birds fed the diet supplemented with L-tryptophan compared with those fed the control diet Also the diet containing L-tryptophan did not affect fertility and hatchability of settable egg though the number of quality chicks per sellable egg was higher significantly(P＜0.05) in birds fed the L-tryptophan than that fed the control diet.

• Natural Product Sciences
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• v.28 no.3
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• pp.138-142
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• 2022

Alzheimer's disease (AD) is the most common age-related neurodegenerative disease in industrialized countries. It is estimated that about 47 million people living with dementia and the number of cases will be tripled by 2050. However, the exact mechanism of AD is not known, and full therapy has still not been found. Various tryptophan-derived alkaloids have been reported as promising agents for the treatment of AD. In the present study, a series of tryptophan-derived alkaloids were isolated and characterized from the methanol extract of Hedera rhombea fruit. Based on the analysis of their observed and reported spectroscopic data, their structures were identified as N-[4'-hydroxy-(E)-cinnamoyl]-L-tryptophan (1), N-[3',4'-dihydroxy-(E)-cinnamoyl]-L-tryptophan (2), N-[4'-hydroxy-(E)-cinnamoyl]-L-tryptophan methyl ester (3), and N-[3',4'-dihydroxy-(E)-cinnamoyl]-L-tryptophan methyl ester (4). These compounds were screened for anti-Alzheimer activity via their inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes in vitro. As a result, compounds 3 and 4 showed moderate BChE inhibition with IC₅₀ values of 86.9 and 78.4 μM, respectively, compared to those of the positive control [berberine (IC₅₀ = 11.5 μM)]. However, all four compounds did not show significant inhibition of the AChE enzyme. This is the first time, the AChE and BChE inhibitory activities of these tryptophan-derived alkaloids were investigated and reported.

• KSBB Journal
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• v.7 no.4
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• pp.284-289
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• 1992

The optimum conditions for the production of tryptophan using a recombinant Klebsiella pnuemoniae phe A tyr A trp R/pSC 101-$trp^{+}$ and its plasmid stability during tryptophan production were studied. The optimum temperature was $37^{\circ}C$ and the specific growth rate was 1.05$h^{-1}$ at $37^{\circ}C$. Tryptophan production was increased by glucose fed-batch culture, and tryptophan was accumulated to 0.175 g/l after 36 hrs. This amount was about 1.2 and 1.6 times greater than that obtained from batch culture and flask culture, respectively. The stability of the strain in fed-batch cu1ture was greatly different from that in repeated flask culture. After 6 generation, 95% of total cells was stable in repeated flash culture, but in fed-batch culture only 50% was stable.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.1
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• pp.52-58
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• 1995

5-methyltryptophan（5MT） resistant mutant plants （MRl） were analyzed for characterization of anthranilate synthetase （AS） and tryptophan synthetase （TS） enzymes. The enzyme was measured in crude extracts from MR1 and control seedlings of Danggin inbred line. There was no significant difference in the level of AS between MR1 and control seedlings when grown on MS medium without 5MT. However, MR1 seedlings grown on MS medium with 25mg/L 5MT showed the level of AS twice higher than that of control seedlings. The activity of AS was inhibited to 50％ in untreated plants when 4mg /L L-tryptophan was added to their extracts. Extracts from MR1 plants required about four times higher concentration of amino acid to cause equal inhibition. In the TS assay, the activity observed in MR1 seedlings was four times higher than that of control seedlings. We have also isolated and sequenced the gene which encoding the tryptophan synthetase B subunit （TSB） from maize. The gene encodes polypeptides with high homology to TSB isolated from other plants, and is expressed in all the developmental stages examined. Northern hybridization analysis indicated that the gene expression in MR1 seedlings grown on MS medium showed a higher level than in control seedlings.

• Microbiology and Biotechnology Letters
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• v.20 no.1
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• pp.73-78
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• 1992

- Enzymatic synthesis of L-tryptophan(Trp) using E. coli tryptophanase has been investigated. In order to reduce the substrate inhibition by indole and to increase the product yield of L-tryptophan three different approaches have been made in this work. First, indole was intermittently fed to the reaction mixture in order to control the indole concentration at lower level. When 15 mM of indole was used as a total amount of substrate, conversion yield of 80% has been obtained with intermittent feeding while only 20% of indole was converted into L-tryptophan by conventional batch operation, The second method employed in this work was the use of cyclohexane-phosphate buffer organic two-phase system. In this system, indole was mainly partitioned into the organic-solvent phase and therefore substrate inhibition was expected to be reduced. L-Tryptophan production in organic two-phase system was, however, unexpectedly lower than that obtained in aqueous buffer solution. As a third method cyclodextrins have been added to the aqueous reaction mixture. It was found that the addition of $\beta$-cyclodextrin enhanced the tryptophan synthesis noticeably while $\alpha$-cycfodextrin showed little effect on tryptophan production.