• 한국미생물·생명공학회지
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• 제20권6호
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• pp.704-706
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• 1992

A model peptide, N-carbobenzoxy-L-phenylalanyl-L-phenylalanine methyl ester, was synthersized with free and immobilized thermolysin in a microaqueous system. The model peptide was formed mostly during the initial phase of the reaction. The yields of the compound with free and immobilized thermolysin after 4hr of reaction were 77.8 and 71.2, respectively.

• 약학회지
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• 제44권3호
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• pp.279-282
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• 2000

The inhibition mode of S-hydroxy-2-phenylalanylaminomethyl-4-pyron ($IC_{50}=24.6{\;}{\mu}M$) on mushroom tyrosinase was investigated using L-tyrosine as a substrate. This inhibitor is the kojic acid derivative, where the C-7 hydroxyl of kojic acid was replaced by amino group and coupled to the carboxyl of L-phenylalanine. The kinetic data obtained show a competitive inhibition pattern.

• Journal of Microbiology and Biotechnology
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• 제25권6호
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• pp.782-787
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• 2015

In this study, we developed an assay system for missense mutations in human phenylalanine hydroxylases (hPAHs). To demonstrate the reliability of the system, eight mutant proteins (F39L, K42I, L48S, I65T, R252Q, L255V, S349L, and R408W) were expressed in a mutant strain (pah^-) of Dictyostelium discoideum Ax2 disrupted in the indigenous gene encoding PAH. The transformed pah - cells grown in FM minimal medium were measured for growth rate and PAH activity to reveal a positive correlation between them. The protein level of hPAH was also determined by western blotting to show the impact of each mutation on protein stability and catalytic activity. The result was highly compatible with the previous ones obtained from other expression systems, suggesting that Dictyostelium is a dependable alternative to other expression systems. Furthermore, we found that both the protein level and activity of S349L and R408W, which were impaired severely in protein stability, were rescued in HL5 nutrient medium. Although the responsible component(s) remains unidentified, this unexpected finding showed an important advantage of our expression system for studying unstable proteins. As an economic and stable cell-based expression system, our development will contribute to mass-screening of pharmacological chaperones for missense PAH mutations as well as to the in-depth characterization of individual mutations.

• 한국식품과학회지
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• 제24권5호
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• pp.504-510
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• 1992

고정화 thermolysin에 의한 아스파탐 전구체의 하나인 N-Benzoylaspertame(BzAPM)의 합성을 효율적으로 할 수 있는 수용성 유기용매가 함유된 용매계를 산정하고자 하였다. BzAPM 및 L-phenylalanine(Phe)의 용해도는 methanol 45%가 함유된 용매계에서 각각 1.84 및 1.79%로 가장 높았으며, dimethyl sulfoxlilde(DMSO) 25%와 polyethylene glycol(PEG) 200 20%가 함유된 혼합 용매계도 비교적 높은 용해도를 보였다. BzAPM의 용해도는 ethylene glycol류의 분자량이 커질수록 용해도가 증가하였으나, Phe의 경우에는 이러한 경향을 나타내지 않았다. 고정화 thermolysin에 의한 BzAPM의 합성역가는 methanol 45% 및 DMSO 45%의 난일 유기용매계와 DMSO 25% 및 PEG 200 20%가 함유된 혼합 용매계에서 높게 나타났으며, 초기 합성속도도 빠른 것으로 나타났다. $40^{\circ}C$에서 42일간 고정화 효소를 보관하였을 때, thermolysin은 DMSO 25%와 PEG 200 20%가 함유된 용매계에서 가장 안정하였다. L-phenyalanine methyl ester의 비효소적 가수분해 속도는 methanol함유 용매계에서 가장 낮았고, DMSO 25%와 PEG 200이 함유된 용매계에서는 이들의 중간 정도인 것으로 확인되었다. 그리하여 고정화 thermolysin에 의한 BzAPM의 합성에 적합한 용매계로서 DMSO 25% 및 PEG 200 20%가 함유된 용매계를 선정하였다.

• Plant Biotechnology Reports
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• 제2권2호
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• pp.133-136
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• 2008

Cell cultures of Commiphora wightii (Arnott.) Bhandari were grown in shake flasks and a bioreactor and an increase in guggulsterone accumulation up to $18{\mu}g\;l^{-1}$ was recorded in cells grown in the production medium containing a combination of sucrose:glucose (4% total), precursors (phenylalanine, pyruvic acid, xylose, and sodium acetate), morphactin, and 2iP. A yield of $10g\;l^{-1}$ biomass and ${\sim}200{\mu}g\;l^{-1}$ guggulsterone was recorded in a 3-l flask and in a 2-l stirred tank bioreactor compared with 6.6 g biomass and $67{\mu}g\;l^{-1}$ guggulsterone in 250-ml flasks. Increased vessel size was correlated with increased biomass and guggulsterone accumulation. 2iP alone was not effective for biomass and guggulsterone accumulation in cell cultures of C. wightii.

• 생명과학회지
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• 제17권2호통권82호
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• pp.286-292
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• 2007

마늘주의 산업화에 앞서 기초 자료로써 활용하고자, 마늘을 소주 등의 술에 침지하였을 때 마늘의 휘발성 기능성분과 유리아미노산이 술로 침출되는 정도 및 형태에 관하여 조사하고자, 생마늘을 20% 주정에 5주간 침지하고 매주 휘발성 향기성분과 유리아미노산들이 침출되는 양적 및 형태적 변화를 조사하였다. 마늘의 주요 유리 아미노산은 L-aspartic acid, L-glutamic acid, L-arginine, L-alanine, L- proline, L-asparagine 및 L-serine이었으며, 유리 아미노산들 모두 침지 기간의경과에 따라 침출량이 증가하였다. 또한, L-threonine, L-proline, L-valine 및 L-leucine 등의 중성아미노산들과 방향족아미노산인 tyrosine과 phenylalanine은 3주 후부터 80% 이상 침출된 반면에, 산성, 염기성 및 함황아미노산들은 5주 후에도 80% 미만이었다. 생마늘의 휘발성 향기성분은 diallyl trisulfide, diallyl disulfide, methyl allyl disulfide, 2-vinyl-4H-1,3-dithiin, 3-vinyl-3,4-dihydro-1,2-dithiin, 3,5-diethyl-1,24-trithiolane, isobutyl isothiocyanate 및 diallyl sulfide 등의 황화합물들이 주요 성분들이었다. 생마늘로부터 주정으로 침출된 휘발성 향기성분은 allyl alcohol, diallyl disulfide, 3,5-diethyl-1,2,4-trithiolane, diallyl trisulfide, 3,4-dimethoxyfuran의 5종이었으며, 침지기간의 경과에 따라 3,5-diethyl-1,2,4-trithiolane는 계속 침출량이 증가하였지만 그 외 4종은 감소하였다. 침 지기간 중 furfural, 5-methylfurfural, 5-hydroxymethylfurfural, dimethyl pyrazine, furfuryl alcohol, 3-hydroxy-2-bytanone과 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one이 새로이 생성되었으며, 침지기간의 경과에 따라 침출주에 대부분 축적되는 양상을 보였다.

• 대한화장품학회지
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• 제44권3호
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• pp.327-334
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• 2018

조류 소재에 관한 연구는 꾸준히 진행되고 있다. 본 연구에서는 미역, 다시마, 불등가사리 등 해조류를 혼합한 발효추출물의 항산화, 미백, 보습의 활성 실험을 진행하였다. 또한 유산균으로는 김치유산균 Lactobacillus sakei균주를 이용하였다. 복합해조류 발효추출물의 생리활성 실험을 진행하였으며, 1,1-diphenyl-2-picrylhydrazyl(DPPH), 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS) 라디칼 소거능에서는 양성대조군 보다 높은 저해효능을 보였다. 미백효능 실험에서는 3,4-dihydroxy-L-phenylalanine (L-DOPA), mushroom tyrosinase 실험을 수행하였으며, 발효 전보다 발효 후의 미백활성이 높게 나타나는 것을 확인할 수 있었다. 한편, 해조류 소재의 유효성분인 fucose에 대한 HPLC분석을 수행하였으며, 용매조건에 대한 표준화 방법을 새로이 정립하였다. 이 연구는 복합해조류 추출물이 항산화, 미백 등 화장품 소재로서 가능성을 제안할 수 있다.

• Journal of Microbiology and Biotechnology
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• 제23권12호
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• pp.1791-1801
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• 2013

Diketopiperazine is produced by various organisms, including bacteria, fungi, and animals, and has been suggested as a novel signal molecule involved in the modulation of genes with various biological functions. Vibrio vulnificus, which causes septicemia in humans, produces cyclo($\small{L}$-phenylalanine-$\small{L}$-proline) (cFP). To understand the biological roles of cFP, the effect of the compound on the expression of the total mRNA in V. vulnificus was assessed by next-generation sequencing. Based on the transcriptomic analysis, we classified the cFP-regulated genes into functional categories and clustered them according to the expression patterns resulted from treatment with cFP. From a total of 4,673 genes, excepting the genes encoding tRNA in V. vulnificus, 356 genes were up-regulated and 602 genes were down-regulated with an RPKM (reads per kilobase per million) value above 3. The genes most highly induced by cFP comprised those associated with the transport and metabolism of inorganic molecules, particularly iron. The genes negatively regulated by cFP included those associated with energy production and conversion, as well as carbohydrate metabolism. Noticeably, numerous genes related with biofilm formation were modulated by cFP. We demonstrated that cFP interferes significantly with the biofilm formation of V. vulnificus.

• 대한유전성대사질환학회지
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• 제2권1호
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• pp.89-94
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• 2002

목 적 : 한국에서 처음 개발된 페닐케톤뇨증 소아를 위한 특수분유를 1년간 섭취시켜 발달양상 및 치료결과를 관찰하여 효율성과 안정성을 확인하고자 하였다. 방 법 : 순천향대학병원에서 페닐케톤뇨증으로 진찰된 소아 14명을 대상으로 1년간 수유하면서 식이 일기 평가, 혈장 아미노산 분석, 일반혈액검사, ferritin, 간기능검사, 소변검사를 시행하였다. 결 과 : 14명 모두 잘 먹었으며 신장, 체중, 두위는 모두 정상발육을 보였다. 혈색소는 모두 정상범위였다. 14례중 4례에서 ferritin 치가 12 ng/mL 이하여서 철분체제를 투여하였다. 알부민 치, S-GOT, S-GPT 소변검사는 모두 정상이었다. 페닐알라닌 치는 0.7-15.6 mg/dL로 대부분 정상 범위로 잘 유지되었다. 발진, 설사, 변비 등의 부작용은 관찰되지 않았다. 결 론 : 국내에서 처음 개발된 PKU-1과 PKU-2 Formula의 발육양상과 치료 결과가 좋은 것으로 확인되어 환자에게 안심하고 사용할 수 있는 우수한 제품으로 사료된다.

• Journal of Animal Science and Technology
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• 제63권1호
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• pp.114-124
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• 2021

The objective of this study was to characterize the enzymatic hydrolysis of lipopolysaccharide (LPS) by wheat phytase and to investigate the effects of wheat phytase-treated LPS on in vitro toxicity, cell viability and release of a pro-inflammatory cytokine, interleukin (IL)-8 by target cells compared with the intact LPS. The phosphatase activity of wheat phytase towards LPS was investigated in the presence or absence of inhibitors such as L-phenylalanine and L-homoarginine. In vitro toxicity of LPS hydrolyzed with wheat phytase in comparison to intact LPS was assessed. Cell viability in human aortic endothelial (HAE) cells exposed to LPS treated with wheat phytase in comparison to intact LPS was measured. The release of IL-8 in human intestinal epithelial cell line, HT-29 cells applied to LPS treated with wheat phytase in comparison to intact LPS was assayed. Wheat phytase hydrolyzed LPS, resulting in a significant release of inorganic phosphate for 1 h (p < 0.05). Furthermore, the degradation of LPS by wheat phytase was nearly unaffected by the addition of L-phenylalanine, the inhibitor of tissue-specific alkaline phosphatase or L-homoarginine, the inhibitor of tissue-non-specific alkaline phosphatase. Wheat phytase effectively reduced the in vitro toxicity of LPS, resulting in a retention of 63% and 54% of its initial toxicity after 1-3 h of the enzyme reaction, respectively (p < 0.05). Intact LPS decreased the cell viability of HAE cells. However, LPS dephosphorylated by wheat phytase counteracted the inhibitory effect on cell viability. LPS treated with wheat phytase decreased IL-8 secretion from intestinal epithelial cell line, HT-29 cell to 14% (p < 0.05) when compared with intact LPS. In conclusion, wheat phytase is a potential therapeutic candidate and prophylactic agent for control of infections induced by pathogenic Gram-negative bacteria and associated LPS-mediated inflammatory diseases in animal husbandry.