• KSBB Journal
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• 제6권3호
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• pp.321-325
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• 1991

본 연구에서는 매생물발효에 의한 L-phenylalanine생산에 미치는 배지조성의 영향을 살펴보았다. 탄소원의 선택은 L-phenylalanine생산에 큰 영향을 미침을 알았다. 자당, 포도당, 과당 혹은 그 혼합물을 탄소원으로 사용할때에 비해 당밀을 사용하는 것이 L-phenylalapine악 생산성을 크게 향상시켜 주었다. 최소배시의 사용시 미량의 염류들이 요구됨을 확인하였으나, 과량으로 첨가하면 더이상의 효고는 없었다. 또한 세포의 증식과 아미노산의 생산에 있어 적정량의 biotin과 thiamine이 필요함도 알I 수 있었다. Corynehacterium 균주외에 L.phenylalanine생산주로 알려진 조절기작을 상실한 영양요구성 변이주인 Brev-ihacterium lactofermenticum과 Arthrohacter citreus의 생산능을 조사해본 결과, Corynehacterium에 비해 생산성이 낮았으며 역시 영양요구 성질을 잃어버린 것으로 확인되었다.

• 한국미생물·생명공학회지
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• 제15권2호
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• pp.80-83
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• 1987

Rhodotorula glutinis IFO 0559에서 유래하는 L-phenylalanine ammonia lyase(EC 4. 3. 1. 5)를 이용하거나, 유도된 세포자체를 이용하여 trans-cinnamic acid로부터 L-phenylalanine을 생합성할 때 극단적인 반응액이 미치는 효소 및 세포의 안정성에 대하여 조사하였다. 그리고 안정제를 첨가한 60％의 glycerol은 효소의 안정화에 효과를 보였으며 trans-cinnamic acid에서 L-phenylalanine으로의 전이율은 80％까지 되었다. 이에 아울러 전이율을 보다 신속하고 정확히 측정할 수 있는 wavelength scanning 방법을 개발하였다.

• KSBB Journal
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• 제5권2호
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• pp.125-131
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• 1990

본 연구에서는 인공감미료 aspartamed의 원료인, I-phenylalanine을 생산하는 tyrosine auxotroph이며 다수의 아미노산 유도체의 저항성이 있는 변이주 Corynebact-erium glutamicum ATCC21674배양의 동특성을 조사하였다. 이 균주는 tyrosine이 존재하지 않아도 성장하고 또한 과량의 tyrosine을 함께 생성하는 것으로 보아 autotrophic mutant가 reversion된 revertant로 추정된다. 대수증식기에서의 비증식속도는 $0.087hr^-1$이었다. Phen-ylalanine 최대생성속도는 세포증식이 끝날 때에 얻어졌으며 세포량의 증가는 이산화탄소의 생산량의 증가와 비례함을 알 수 있었다. 이산화탄소 생성속도는 당소비속도와도 비례하므로 이를 이용하여 발효상태를 알 수 있는 유용성이 확인되었다.

• Journal of Microbiology and Biotechnology
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• 제8권3호
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• pp.237-244
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• 1998

A study was carried out to elucidate the relation between the production of flavonol glycosides and the change of phenylalanine ammonia-lyase activity in cell suspension cultures of Ginkgo biloba by the unassisted and synergistic effects of various factors. The quercetin production showed a mixed-growth-associated pattern in cell suspension cultures. Fluorescent light and UV radiation increased phenylalanine ammonia-lyase (PAL) activity, and resulted in the increase of the production of quercetin and kaempferol ten- and four-fold, respectively, as compared to that obtained in the normal culture condition. The cell growth of Ginkgo biloba was enhanced .at higher temperatures whereas the quercetin production was at its maximum at low temperatures. Moreover, the quercetin production was increased by temperature change during the culture period. In particular, the quercetin production was at the highest level when the culture temperature was elevated from $10^{\circ}C\;to\;30^{\circ}C$. The addition of phenylalanine as a precursor in the culture medium stimulated an 8-fold increase in the production of quercetin; the addition of naringenin caused a l0-fold increase. The quercetin production was also greatly increased by feeding enzyme cofactors such as 2-ketoglutarate and ascorbic acid in the culture medium, but specific PAL activity was not increased except with phenylalanine feeding. The synergistic effect of UV radiation and naringenin feeding was observed, resulting in the increase of flavonol glycoside production at a rate higher than in any other case investigated.

• 한국미생물·생명공학회지
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• 제19권5호
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• pp.433-438
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• 1991

Phenylalanine 고생산용 plasmid pSY130-14는 $\lambda$-phage 유래 온도감수성을 가지고 있으므로 $cI_{857}$ repressor와 PL과 PR을 온도를 올려 phenylalanine의 생산을 유도한다. pSY130-14를 갖는 E.coli AT2471은 kanamycin 무첨가, $38.5^{\circ}C$, 48시간에서 약 30%로 plasmid가 없어지며 첨가에서 안정성이 떨어졌다가 배양시간과 더불어 올라갔는데, 이것은 생육에 피요한 kanamycin gene과 ori만이 남는 것으로 생각된다.

• Applied Biological Chemistry
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• 제38권1호
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• pp.13-19
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• 1995

Phenylalanine 생산시 tyrosine이 부생되지 않도록 tyrA유전자 발현이 낮은 여러 가지 온도조절형 plasmid를 제작하였으며, phenylalanine 생산균주인 대장균 AT2471$[tyrA^-,\;thi^-]$은 tyrosine 영양요구 변이균주이므로 생산배지에 tyro-sine 첨가없이 phenylalanine을 생산할 수 있도록 하기 위하여 tyrosine 복귀변이균주를 분리하여 phenylalanine 생산을 검토하였다. 2.5 l jar fermenter를 사용하여 tyrosine 첨가없이 phenylalanine 생산을 검토하여 대장균 AT2471/pSY146A, 대장균 AT2471 tyrosine 복귀변이균주 5/pSY111-14를 $39^{\circ}C$에서 55시간 배양한 결과 각각 12 g/l, 15 g/l를 생산하였다.

• Food Science and Biotechnology
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• 제18권4호
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• pp.954-958
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• 2009

Effects of controlled- and uncontrolled-pH operations on phenylalanine ammonia lyase (PAL) production by a recombinant Escherichia coli strain were investigated at uncontrolled-pH ($pH_{UC}$) and controlled-pH ($pH_C$) of 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, and 8.5 in bioreactor systems. The results showed that the recombinant PAL activity was improved significantly by controlled pH strategy. Among the $pH_C$ operations, the highest PAL activities were obtained under $pH_C$ 7.5 strategy where cell mass ($OD_{600\;nm}$) and PAL activity was 1.3 and 1.8 fold higher than those of $pH_{UC}$, respectively. The maximum PAL activity reached 123 U/g. The $pH_C$ 7.5 strategy made recombinant plasmid more stable and therefore allowed easier expression of PAL recombinant plasmid, which increased PAL production. It was indicated that the new approach (controlled-pH strategy) obtained in this work possessed a high potential for the industrial production of PAL, especially in the biosynthesis of L-phenylalanine.

• 한국식품영양학회지
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• 제9권1호
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• pp.21-28
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• 1996

This study was attempted to investigate the production of L-tyrosine by Brevibacterium flavum ATCC 14067. To select the strain which produce more L-tyrosine, mutants were induced by N-methyl-N'-nitro-nitrosoguanidine (NTG) treatment and phenylalanine auxotrophic mutants were induced by NTG and penicillin treatments. PFP resistant mutant was isolated from a phenylalanine auxotroph by retreatment with NTG and screened for increase of L-tyrosine production. PFP-326 mutant resistant to PPP (100ug/ml) was derived from phenylalanine auxotroph by mutagenesis with NTG and PFP-106 mutant resistant to PFP (1201g/ml) was derived from PFP-326 by mutagenesis with NTG. The composition of media for L-tyrosine production in strain PFP-106 was studied. PFP-106 mutant strain produced 50mg 11 of L-tyrosine while the parent strain produced 0.56mg 11 of L-tyrosine. The optimum composition of medium for L-tyrosine by strain PFP-106 was 10cA sucrose as carbon source, 3% ammonium sulfate as nitrogen source. The optimum cultural condition for producing L-tyrosine by strain PFP-106 was L-phenylalanine at a concentration of 1000g/mg.

• 생약학회지
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• 제27권4호
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• pp.301-308
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• 1996

Hairy roots induced from stems of Rubia cordifolia var. pratensis were cultured in the liquid medium under a variety of auxins to find the optimal condition for the growth and production of pigments. Culture of the hairy roots on NN liquid medium containing NAA 0.5 mg/l was best for growth of hairy roots. Production of yellow anthraquinone derivatives and purpurin in hairy roots was enhanced by the culture on NN liquid medium without auxins. Effects of L-phenylalanine, L-tyrosine and juglone, synthesized via the shikimic acid pathway, on growth and production of pigments in hairy roots were studied in the present study. Concentration of exogeneous L-phenylalanine. L-tyrosine and juglone in liquid culture system of hairy root containing NAA 0.1 mg/l was decreased quickly in its early stages of the culture period. Addition of juglone to NN liquid medium containing NAA 0.1 mg/l enhanced the productivity of pigments in hairy roots.

• Applied Biological Chemistry
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• 제31권4호
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• pp.376-381
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• 1988

Rhodotorula glutinis IFO 0559에 의한 transcinnamic acid와 암모니아로부터 L-Phenylalanine 생산의 최적 조건을 검토하였다. L-phenylalanine 생산은 반응액으로 200mM transcinnamic acid, 4M $NH_4OH$, 250mM$(NH_4)_2SO_4$, 0.005% cetylpyridiniurn chloride (pH 10.5), 50mg/m1건조균체를 사용하였을 때 최대 생산량을 나타내었다. 비수용성 유기용매중에서 petroleum ether가 가장 효과적인 유기용매이였으며 반응액에 50% 첨가시 가장 효과가 좋았다. 최적 반응조건하에서 12시간 반응후 L-phenylalanine이 21.19생성되었으며, 이때의 trans-cinnamic acid의 전환율은 63.9%이었다.