• BMB Reports
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• 제36권2호
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• pp.149-153
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• 2003

The dibucaine number (DN) was determined for serum cholinesterase (EC 3.1.1.8, SChE) in plasma samples. The ones with a DN of 79-82 were used, because they had the "usual" SChE variant. The enzyme was assayed colorimetrically by the reaction of 5,5'-dithiobis-[2-nitrobenzoic acid] (DTNB) with the free sulfhydryl groups of thiocholine that were produced by the enzyme reaction with butrylthiocholine (BuTch) or acetylthiocholine (AcTch) substrates, and measured at 412 nm. Dibucaine, a quaternary ammonium compound, inhibited SChE to a minimum within 2 min in a reversible manner. The inhibition was very potent. It had an $IC_{50}$ of $5.3\;{\mu}M$ with BuTch or $3.8\;{\mu}M$ with AcTch. The inhibition was competitive with respect to BuTch with a $K_i$ of $1.3\;{\mu}M$ and a linear-mixed type (competitive/noncompetitive) with respect to AcTch with inhibition constants, $K_i$ and $K_I$ of 0.66 and $2.5\;{\mu}M$, respectively. Dibucaine possesses a butoxy side chain that is similar to the butryl group of BuTch and longer by an ethylene group from AcTch. This may account for the difference in inhibition behavior. It may also suggest the existence of an additional binding site, other than the anionic binding site, and of a hydrophobic nature.

• 한국가축번식학회지
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• 제22권4호
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• pp.331-339
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• 1998

본 연구는 Sertoli 세포 column 과 Sertoli 세포돌기 미세구조의 연구를 위해 당질검출을 위한 PA-TCH-SP, -PD 투과전자현미경용 특수염색을 정세관에 적용한 후 각 정세포와 Sertoli 세포를 관찰하고 비교하여 이 분야 연구에 본염색법의 적용 가능성을 검토하였다. PA-TCH-SP, -PD 특수염색을 개의 정세관에 적용하여 투과전자현미경으로 관찰하였던 바, Sertoli 세포 column 과 돌기 부위에 수많은 반응과립이 관찰되었으며 정세관 기저부의 정조세포질에서도 약간의 반응과립이 관찰되었다. 이와 같은 반응과립은 각 정세포의 핵, 정모세포질, 정자세포질 및 잔류체에는 존재하지 않아 반응과립이 존재하는 Sertoli 세포 colunm 과 돌기 및 정자세포질에 침투된 돌기들을 명확히 구분할 수 있었다. 따라서 PA-TCH-SP, -PD 염색법은 투과전자현미경하에서 Sertoli 세포 colunm 과 돌기의 형태학적 및 기능학적 연구에 대단히 유용한 염색법으로 사료된다.

• Plant Biotechnology Reports
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• 제2권4호
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• pp.253-258
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• 2008

The cDNA of the touch-induced genes (TCH) of the sweet potato [Ipomoea batatas (L.) Lam.] has been cloned and analyzed. IbTCH1, which exists as at least two-copy genes in the genome of the sweet potato, encodes for 148-amino acid polypeptides, and harbors four conversed $Ca^{2+}-binding$ motif EF-hands. IbTCH1 was shown to be expressed in the flower, leaf, thick pigmented root, and particularly in the white fibrous root, but expressed only weakly in the petiole. IbTCH1 is upregulated upon exposure to environmental stresses, dehydration, and jasmonic acid. Furthermore, IbTCH1 is developmentally regulated in the leaf and root. These results strongly indicate that the gene performs functions in both plant development and in defense/stress-signaling pathways.

• Bulletin of the Korean Chemical Society
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• 제24권1호
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• pp.65-69
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• 2003

The kinetic and chemical mechanisms of AChE-catalyzed hydrolysis of short-chain thiocholine esters are relatively well documented. Up to propanoylthiocholine (PrTCh) the chemical mechanism is general acid-base catalysis by the active site catalytic triad. The chemical mechanism for the enzyme-catalyzed butyrylthiocholine(BuTCh) hydrolysis shifts to a parallel mechanism in which general base catalysis by E199 of direct water attack to the carbonyl carbon of the substrate. [Selwood, T., et al. J. Am. Chem. Soc. 1993, 115, 10477- 10482] The long chain thiocholine esters such as hexanoylthiocholine (HexTCh), heptanoylthiocholine (HepTCh), and octanoylthiocholine (OcTCh) are hydrolyzed by electric eel acetylcholinesterase (AChE). The kinetic parameters are determined to show that these compounds have a lower Michaelis constant than BuTCh and the pH-rate profile showed that the mechanism is similar to that of BuTCh hydrolysis. The solvent isotope effect and proton inventory of AChE-catalyzed hydrolysis of HexTCh showed that one proton transfer is involved in the transition state of the acylation stage. The relationship between the dipole moment and the Michaelis constant of the long chain thiocholine esters showed that the dipole moment is the most important factor for the binding of a substrate to the enzyme active site.

• Journal of Plant Biotechnology
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• 제45권1호
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• pp.71-76
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• 2018

The Arabidopsis SHL1 (${\underline{Sh}}ort$ ${\underline{L}}ife$ 1) gene encodes a small nuclear protein that is critical for the proper expression of the developmental programs that are responsible for controlling plant stature, senescence, flowering and seed formation. The SHL1 contains a single PHD finger domain that works in conjunction with a bromo-adjacent homology (BAH) motif that is thought to function significantly in protein-protein interactions. The TCH4 gene of the Arabidopsis encodes a xylogluclan endotransglucosylase/hydrolase that is transcriptionally regulated by a variety of hormonal and environmental stimuli. We report here in this study that the SHL1 exhibits sequence specific DNA binding properties, recognizing a 14 bp region of the TCH4 promoter in vitro, spanning nucleotides -262 to -275 (GGAAAAAACTCCCA). Chiefly, the nuclear extracts of Arabidopsis contain a protein with similar binding properties as recombinant SHL1, which is absent in identified transgenic plants that are noted as expressing antisense SHL1 RNA. Interestingly, the SHL1 gene expression with a BL treatment in characteristically wild types of seedlings showed that the transcript level of SHL1 is significantly down regulated by the BL treatment. The SHL1 may play a subtle role in regulating the kinetics of induction of the TCH4 in response to several stimuli in vivo.

• Fisheries and Aquatic Sciences
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• 제25권6호
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• pp.335-349
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• 2022

To optimize the hydrolysis conditions in the production of antioxidant hydrolysates from tuna cooking juice concentrate (TC) to maximize the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, TC containing 48.91% protein was hydrolyzed with Alcalase 2.4 L, and response surface methodology (RSM) was applied. The optimum hydrolysis conditions included a 2.2% (w/v) Alcalase concentration and 281 min hydrolysis time, resulting in the highest DPPH radical scavenging activity of 66.49% (0.98 µmol Trolox/mg protein). The analysis of variance for RSM showed that hydrolysis time was an important factor that significantly affected the process (p < 0.05). The effects of different drying methods (freeze drying, hot air drying, and vacuum drying) on the DPPH radical scavenging activity and amino acid (AA) profiles of TC hydrolysate (TCH) were evaluated. Vacuum-dried TCH (VD) exhibited an increase in DPPH radical scavenging activity of 81.28% (1.20 µmol Trolox/mg protein). The VD samples were further fractionated by ultrafiltration. The AA profiles and antioxidant activities in terms of the DPPH radical scavenging activity, 2,2'-azino-bis(3-ethylbenzthiazoline)-6-sulfonic acid (ABTS) radical scavenging activity, ferric reducing antioxidant power, and ferrous ion chelating activity were investigated. Glutamic acid, glycine, arginine, and cysteine were the major AAs found in the TCH fractions. The highest DPPH radical scavenging activity was found in the VD-1 fraction (< 5 kDa). The VD-3 fraction (> 10 kDa) exhibited the highest ABTS radical scavenging activity and ferric reducing antioxidant power. The ferrous ion chelating activity was the highest in VD-1 and VD-2 (5 to 10 kDa). In conclusion, this study provided the optimal conditions to obtain high antioxidant activities through TCH production, and these conditions could provide a basis for the future application of TCH as a functional food ingredient.

• 대한수의학회지
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• 제36권3호
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• pp.521-529
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• 1996

In an effort to obtain basic data of carbohydrate metabolism during spermiogenesis of the sexually-matured Jindo dog, the glycogen distribution in the testis was investigated by light and transmission electron microscopy. Periodic acid thiocarbohydrazide silver proteinate physical development(PA-TCH-SP-PD) staining method provided better results in the detection of glycogen granules from Sertoli cells and germ cells than the periodic acid schiff(PAS) staining method did. Pre-treatment of the tissue sections with ${\alpha}$-amylase elicited a significant decrease in PA-TCH-SP-PD stained granules, which suggested that the stained granules were of glycogen origin. High concentration of the glycogen granules were observed in the Sertoli cells, especially in its column, sheet-like processes, club-like processes, and tubular processes. The glycogen granules were unevenly distributed in some Sertoli cell columns. These results strongly indicated that the Sertoli cells of Jindo dogs showed vigorous activity of carbohydrate metabolism.

• 대한화장품학회지
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• 제39권4호
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• pp.289-294
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• 2013

본 연구는 미백 소재 개발을 위하여 강진향(Dalbergia odorifera T. Chen) 추출물에서 분리한 활성물질인 biochanin A의 멜라닌 생성에 연관된 효과를 알아보았다. Biochanin A는 B16F1 melanoma 세포에서 농도 의존적으로 멜라닌 양을 억제하였으며, 멜라닌 생합성 저해 효과는 10 ${\mu}g/mL$ 농도에서 멜라닌 생성 억제율이 48%로 나타났다. Western blot을 이용하여 microphthalmia associated transcription factor (MITF), Tyrosinase, Trp-1와 Trp-2의 발현을 억제함을 확인하였다. 따라서 biochanin A는 미백 효능을 갖는 화장품 소재로서의 개발 가능성이 클 것으로 기대된다.

• 한국식품영양학회지
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• 제9권4호
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• pp.490-495
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• 1996

홑파래로부터 황산기를 함유한 다당체를 크로마토그래프로 분리정제하여 rhamnan sulfate가 항보체 활성화에 미치는 영향을 조사하였다. 항보체 활성능력은 F-4-3 획분을 비교군으로 Heparin H-180, Dextran과 비교해 결과 비교군보다 높았고, C4a와 C3a의 C convertase의 형성과 기능을 F-4-3 획분이 억제하였다. 이러한 보체 활성화 양식은 classical pathway 및 alternative pathway로도 경유함을 알 수 있었다.

• Applied Biological Chemistry
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• 제35권1호
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• pp.42-50
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• 1992

한약재를 대상으로 용철 보체 분석법$(TCH_{50})$을 이용, 항보체 활성물질에 대한 전반적인 검색을 실시하였다. 총 55종의 시료의 열수 추출물을 대상으로 동 활성을 측정한 결과, 대조구에 비해 70%이상의 $TCH_{50}(total\;complement\;hemolysis\;of\;50%)$의 감소를 일으키는 비교적 강력한 항보체 활성을 소유한 울금, 대복피, 조각자, 화살나무, 가시오갈피, 인동, 부자, 계피 등 9종의 시료를 선택할 수 있었다. 이들은 pronase 소화 후 활성을 유지한 반면, $NaIO_4$ 산화에 의해 급격한 활성의 감소를 나타냄으로써, 그 활성의 본체가 다당에 기인함을 알 수 있었다. 또한 가장 높은 활성을 보였던 대복피(Areca catchu) 다당의 경우 $Ca^{++}$ 이온 부재시 부분적으로 활성의 감소를 보였으며, 정상인의 혈청과 반응시 C3의 분해산물을 면역 전기 영동법에 의해 확인할 수 있었는 바, 동 사실로부터 대복피의 보체 활성화 기구는 classical pathway뿐만 아니라 alternative pathway도 경유함을 알 수 있었다.