• Biotechnology and Bioprocess Engineering:BBE
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• 제11권3호
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• pp.230-234
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• 2006

In this study, we describe a one-step chemoenzymatic reaction for the production of natural blue pigments, in which the geniposide from Gardenia extracts is transformed by glycosidases to genipin. Genipin is then allowed to react with amino acids, thereby generating a natural blue pigment. The ${\beta}-glycosidases$, most notably Isolase (a variant of ${\beta}-glucanase$), recombinant ${\beta}-glycosidases$, Cellulase T, and amylases, were shown to hydrolyze geniposide to produce the desired pigments, whereas the ${\alpha}-glycosidases$ did not. Among the 20 tested amino acids, glycine and tyrosine were associated with the highest dye production yields. The optimal molar ratio of geniposide to glycine, two reactants relevant to pigment production, was unity The natural blue pigments produced in this study were used to dye cotton, silk, and wool. The color yields of the pigments were determined to be significantly higher than those of other natural dyes. Furthermore, the color fastness properties of these dyes were fairly good, even in the absence of mordant.

• BMB Reports
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• 제41권4호
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• pp.310-315
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• 2008

BirA ligase is a prokaryotic ortholog of holocarboxylase synthetase (HCS) that can biotinylate proteins. This study tested the hypothesis that BirA ligase catalyzes the biotinylation of eukaryotic histones. If so, this would mean that recombinant BirA ligase is a useful surrogate for HCS in studies of histone biotinylation. The biological activity of recombinant BirA ligase was confirmed by enzymatic biotinylation of p67. In particular, it was found that BirA ligase biotinylated both calf thymus histone H1 and human bulk histone extracts. Incubation of recombinant BirA ligase with H3-based synthetic peptides showed that lysines 4, 9, 18, and 23 in histone H3 are the targets for the biotinylation by BirA ligase. Modification of the peptides (e.g., serine phosphorylation) affected the subsequent biotinylation by BirA ligase, suggesting crosstalk between modifications. In conclusion, this study suggests that prokaryotic BirA ligase is a promiscuous enzyme and biotinylates eukaryotic histones. Moreover the biotinylation of histones by BirA ligase is consistent with the proposed role of human HCS in chromatin.

• 대한의생명과학회지
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• 제16권4호
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• pp.279-285
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• 2010

Endogenous cannabinoids (endocannabinoids) display various pharmacological effects including pain control, anti-inflammation, and neuroprotection. The synthesis and release of endocannabinoids are regulated under both physiological and pathological conditions. The main degrading enzyme of endocannabinoid is fatty acid amide hydrolase (FAAH). Therefore we have developed the fluorescence-based assay system for FAAH. We established stable CosM6 cell lines expressing human FAAH. We also synthesized 2-oxo-2H-chromen-7-yl decanoate (DAEC) as a fluorogenic substrate for FAAH. When crude membrane extracts stably expressing FAAH was incubated with DAEC at $25^{\circ}C$, FAAH reacted specifically to DAEC and catalyzes the hydrolysis of DAEC into decanoic acid and highly fluorescent coumarin. Furthermore, the serin hydrolase inhibitor, phenylmethanesulfonylfluoride, inhibited the coumarin release to the reaction buffer in concentration dependent manner. This assay system is suitable for high-throughput screening since this system has simple experimental procedure and measurement method.

• 생약학회지
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• 제19권3호
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• pp.201-207
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• 1988

Samples of red ginseng, which had been manufactured and packaged by the Korean Monopoly Corporation, were stored at ambient temperatures and humidities ($12{\sim}28^{\circ}$ and $55{\sim}68$ percent) for one to nine years to examine their overall quality stability. The proximate compositions, contents of 50% ethanol and water extracts of the samples and the TLC and HPLC patterns of ginsenosides in the samples remained almost unchanged in all cases. The lipids and fatty acids in the samples, which are otherwise susceptible to oxidation, were stable judged on the basis of the changes of the TLC and GLC patterns of the lipids and fatty acids. It was also found that polyunsaturated fatty acids such as linoleic(C18:2) and linolenic and(C18:3) present in the samples had been very stable during the long storage periods. It, therefore, seems that the autoxidations of the lipid and fatty acids of red ginseng were prevented by antioxidative compounds which will be progressively formed in red ginseng through non-enzymatic browning reactions during manufacturing process and long-term storage.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.270-270
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• 2017

Brown rice flour (BRF) was treated with different carbohydrases (Viscozyme, Termamyl, Celluclast, AMG, Ultraflo, and Pentopan), and then aqueous alcoholic extracts (70% ethanol) from the treated RBF were examined for their phenolic compositions and antioxidant activities (ABTS and DPPH radical scavenging activity). All the carbohydrases tested induced significant increases in ABTS radical scavenging activity (2.1-3.0 times). Moreover, These enzymes increased the amount of extractable free phenolic acids by 10-15 times, especially for ferulic and p-coumaric acid. Among the enzymes tested, Pentopan which was active in arabinoxylan hydrolysis appeared to be most effective in increasing the free phenolic acid content and ABTS radical scavenging activity than other enzymes. Enzymatic hydrolysis of cell wall polysaccharides in BRF could be used as an effective procedure for raising the amount of extractable phenolic acids and thus increasing the antioxidant activity of BRF extract.

• Food Science and Biotechnology
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• 제14권5호
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• pp.614-620
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• 2005

The antioxidative effect of Ecklonia cava, a brown marine alga, was investigated on radical scavenging, including 1,1-diphenyl-2-picrylhydrazyl (DPPH), and hydroxyl and alkyl radicals, using an electron spin resonance (ESR) technique, and on the inhibition of $H_2O_2$-induced DNA damage using comet assay. E. cava was enzymatically hydrolyzed with five food industrial proteases (Alcalase, Flavourzyme, Kojizyme, Neutrase and Protamex) to prepare water-soluble extracts. All the proteolytic hydrolysates exhibited strong dose-dependent radical scavenging activities (above 80%) at a concentration of $2.5\;{\mu}g/mL$. Kojizyme extract (obtained by proteolytic hydrolysation of E. cava with Kojizyme) showed the highest hydroxyl radical scavenging activity of around 98%. In addition, the $H_2O_2$-induced DNA damage was determined using a comet assay, which was quantified by measuring the tail length. Reduction of DNA damage increased with increasing concentrations of Kojizyme extract from E. cava. These results indicated that E. cava has a potential as a valuable natural antioxidative source.

• Journal of Applied Biological Chemistry
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• 제62권4호
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• pp.385-389
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• 2019

본 연구에서는 홍삼 추출물 제조과정에서 추출 수율을 향상시킬 수 있는 효소를 선별하고 최적의 반응조건을 조사하였다. 상업용 단백질 분해효소 중 Alcalase가 단백질과 탄수화물 수율 향상에 효과적이었으며, 효소 사용량은 홍삼 중량의 2%, 반응 시간은 1.5시간이 적당하였다. 최적의 반응조건으로 홍삼을 Alcalase로 처리한 결과 대조구보다 고형분 수율은 45.1%에서 71.1%로 50% 이상, 총페놀 함량은 0.44%에서 0.80%로 80% 이상 증가하였으며, 항산화 활성은 대조군과 매우 유사하였다. 또한 진세노사이드 함량은 대조구의 1.48 mg/g에서 1.98 mg/g으로 30% 이상 증가하였다.

• 한국식품영양학회지
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• 제9권4호
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• pp.413-418
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• 1996

식물 세포벽으로부터 펙틴을 추출하는데 있어 펙틴의 중합도를 높인 고 기능의 펙틴을 추출하기 위해 펙틴의 효소추출법을 사용하여 기존의 고온 산처리 펙틴 추출법과 비교하여 다음과 같은 결론을 얻었다. 1. 불용성의 WAIP로부터 일련의 산 추출 공정과 hemicellulase를 이용한 일련의 효소 추출 공정을 거친 결과, 추출물의 수율은 효소 추출법이 더 높았다. 2. 효소 추출법에 있어 추출 조건을 다양하게 변화시켜 가며 수율을 검토한 결과, 최적의 추출 조건은 hemicellulase 1.5g을 24hr동안 38$^{\circ}C$에서 반응시킨 것으로 나타났다. 3. 펙틴의 주요 성분인 galacturonic acid 함량으로 추출물의 펙틴 순도와 수율을 비교한 결과 산 추출물에 비해 효소 추출물은 수율은 높은 대신 순도가 낮았고 메톡실 함량은 비슷하였다. 4. 효소 추출법에서 추출한 펙틴물질은 중성당 분석, GC, HPLC 등을 통해 성분을 정밀하게 분석하고 다양한 방법으로 고기능 펙틴을 추출할 수 있는 조건도 찾고, 그를 통해 정확한 식물 세포벽 모델이 제시될 수 있을 것이다.

• BMB Reports
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• 제40권1호
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• pp.53-57
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• 2007

The enzymatic properties of NADH:quinone oxidoreductase were examined in Triton X-100 extracts of Bacillus cereus membranes by using the artificial electron acceptors ubiquinone-1 and menadione. Membranes were prepared from B. cereus KCTC 3674 grown aerobically on a complex medium and oxidized with NADH exclusively, whereas deamino-NADH was determined to be poorly oxidized. The NADH oxidase activity was lost completely by solubilization of the membranes with Triton X-100. However, by using the artificial electron acceptors ubiquinone-1 and menadione, NADH oxidation could be observed. The activities of NADH:ubiquinone-1 and NADH:menadione oxidoreductase were enhanced approximately 8-fold and 4-fold, respectively, from the Triton X-100 extracted membranes. The maximum activity of FAD-dependent NADH:ubiquinone-1 oxidoreductase was obtained at about pH 6.0 in the presence of 0.1M NaCl, while the maximum activity of FAD-dependent NADH:menadione oxidoreductase was obtained at about pH 8.0 in the presence of 0.1M NaCl. The activities of the NADH:ubiquinone-1 and NADH:menadione oxidoreductase were very resistant to such respiratory chain inhibitors as rotenone, capsaicin, and $AgNO_3$, whereas these activities were sensitive to 2-heptyl-4-hydroxyquinoline-N-oxide (HQNO). Based on these results, we suggest that the aerobic respiratory chain-linked NADH oxidase system of B. cereus KCTC 3674 possesses an HQNO-sensitive NADH:quinone oxidoreductase that lacks an energy coupling site containing FAD as a cofactor.

• 한국수산과학회지
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• 제29권3호
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• pp.345-356
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• 1996

우렁쉥이 껍질은 다량의 색소를 함유하지만 껌질 자체는 어류가 소화시킬 수 없는 구조를 갖기 때문에 색소분해가 일어나지 않도록 고압 가열하거나 효소처리하여 소화할 수 있는 상태로 만들면 어류 사료에 직접 첨가할 수 있게 된다. 따라서 본 실험은 우렁쉥이 껍질 분말에 viscozyme, celluclast, visco-cell (1:1), ultrazyme 등의 복합효소를 일정량 첨가한 후 $50^{\circ}C$에서 일정시간 분해시키면서 일어나는 화학적 변화를 조사하였다. 불용성 고형분과의 분리능력을 의미하는 상청액율은 효소 첨가구의 농도가 $55.20\~71.88\%$로 효소 무처리구의 $52.68\%$에 비하여 높았고, 고형분 수율도 $800{\mu}l$ 첨가시 까지는 증가하다가 이후 감소하는 경향이었다. 이를 토대로 Duncan multiple test를 하여 각 인자간의 상관관계를 고려한 후 기준 첨가량을 $400{\mu}l$로 하였다. 각 효소의 최적 반응시간을 결정하기 위하여 껍질 분말에 각 효소 $400{\mu}l$를 첨가한 후 20, 40, 60, 120, 180, 240분간 반응시켰다. 효소의 종류에 관계없이 고형분 수율, 상청액율 및 고형분 농도 값이 반응 60분 후에는 거의 변화가 없는 것으로 나타났다. 상청액 중 당 조성을 분석한 결과 viscozyme 처리구는 glucose, N-acetyl-D-galactosamine이 주성분이었고, celluclast 처리구는 glucose, N-acetyl-D-glucosamine이, ultrazyme 처리구는 glucose가 주성분이었으며, visco-cello(1:1) 혼합효소구는 celluclast에 의한 영향이 큰 것으로 나타났다. 껍질은 약 $40\%$의 단백질 (건물량)을 함유하지만, 각 부위별 아미노산 조성은 내피 중의 함량이 가장 높아 21.00g/100g sample이었다. 이들 아미노산 함량중 Asp와 Glu가 가장 많았고, 내피 중 필수아미노산의 함량도 껍질보다 높았다. 껌질 중의 지방산 조성은 매우 다양하였으며, 포화 지방산 중에서는 14 : 0, 16 : 0, 18 : 0가 주성분이었으며, 불포화지방산 중에서는 n-3 계열의 총지질 (TL), 중성지질 (NL), 극성지질 (PL)이 각각 $19.72\%,\;20.44\%,\;20.10\%$였고, n-6 계열의 TL, NL, PL이 각각 $9.21\% \;9.10\%,\;12.18\%$였다. 총 포화지방산의 함량은 PL이 $40.31\%$, NL이 $36.44\%$, TL이 $35.41\%$로 PL의 함량이 높았다.