• Food Science and Biotechnology
• /
• v.18 no.6
• /
• pp.1505-1510
• /
• 2009

Arginyl-fructose (AF) and arginyl-fructosyl-glucose (AFG) were chemically synthesized and purified. Their in vitro and cellular antioxidant activity was investigated using oxygen radical absorbance capacity (ORAC) and cellular antioxidant activity assay, respectively. The peroxyl radical scavenging activity of AF was much higher than that of AFG, which was in good agreement with their reduction capacity to donate electrons or hydrogen atoms. On the other hand, the hydroxyl radical scavenging activity of AF was weaker than that of AFG, which was consistent with their metal chelating activity, suggesting that AFG-$Cu^{2+}$ complex may be less redox-active than AF-$Cu^{2+}$ complex due to 1 glucose molecule attached. The cellular antioxidant activity of AF and AFG appeared to depend on both their permeability into cell membrane and the scavenging activity on peroxyl or hydroxyl radicals. These results indicate that AF and AFG, Maillard reaction products, may have a high potential as a material for the development of nutraceutical food with antioxidant activity.

• Biotechnology and Bioprocess Engineering:BBE
• /
• v.8 no.2
• /
• pp.101-105
• /
• 2003

Recombinant bioluminescent bacteria were used to monitor and classify the to xicity of azo dyes. Two constitutive bioluminescent bacteria, Photobacterium phosphoreum and Es-Cherichia coli, E, coli GC2 (lac::luxCOABE), were used to detect the cellular toxicity of the azo dyes. In addition, four stress-inducible bioluminestent E. coli, DPD2794 (recA::luxCDABE), a DNA damage Sensitive strain; DPD2540 (fabA::luxCDABE), a membrane damage sensitive strain; DPD2511 (katG::luxCDABE), an oxidative damage sensitive strain; and TV1061 (grpE::luxCDABE), a protein damage sensitive strain, were used to provide information about the type of toxicity caused by crystal violet, the most toxic dye of the 16 azo dyes tested. These results suggest that azo dyes result in serious cellular toxicity in bacteria, and that toxicity monitoring and classific ation of some azo dyes, In the field, may be possible using these recombinant bioluminescent bacteria.

• Proceedings of the Korean Society of Life Science Conference
• /
• 2005.09a
• /
• pp.83-83
• /
• 2005

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2007.06a
• /
• pp.737-738
• /
• 2007

• Proceedings of the Korean Biophysical Society Conference
• /
• 2001.06a
• /
• pp.17-17
• /
• 2001

It is well known that myocardial stretch causes changes in electrical signalling and contractility of the heart. For example, mechanical stretch depolarises the membrane potential of cardiac cells and alters the shape of action potentials. As a result, these effects either accelerate the frequency of heart rate or induce arrhythmias of the heart.(omitted)

• BMB Reports
• /
• v.47 no.7
• /
• pp.361-368
• /
• 2014

Lipid components in biological membranes are essential for maintaining cellular function. Phosphoinositides, the phosphorylated derivatives of phosphatidylinositol (PI), regulate many critical cell processes involving membrane signaling, trafficking, and reorganization. Multiple metabolic pathways including phosphoinositide kinases and phosphatases and phospholipases tightly control spatio-temporal concentration of membrane phosphoinositides. Metabolizing enzymes responsible for PI 4,5-bisphosphate (PI(4,5)P2) production or degradation play a regulatory role in Toll-like receptor (TLR) signaling and trafficking. These enzymes include PI 4-phosphate 5-kinase, phosphatase and tensin homolog, PI 3-kinase, and phospholipase C. PI(4,5)P2 mediates the interaction with target cytosolic proteins to induce their membrane translocation, regulate vesicular trafficking, and serve as a precursor for other signaling lipids. TLR activation is important for the innate immune response and is implicated in diverse pathophysiological disorders. TLR signaling is controlled by specific interactions with distinct signaling and sorting adaptors. Importantly, TLR signaling machinery is differentially formed depending on a specific membrane compartment during signaling cascades. Although detailed mechanisms remain to be fully clarified, phosphoinositide metabolism is promising for a better understanding of such spatio-temporal regulation of TLR signaling and trafficking.

• Journal of Microbiology and Biotechnology
• /
• v.30 no.12
• /
• pp.1827-1834
• /
• 2020

Candida albicans is a major fungal pathogen in humans. In our previous study, we reported that an ethanol extract from Aucklandia lappa weakens C. albicans cell wall by inhibiting synthesis or assembly of both (1,3)-β-D-glucan polymers and chitin. In the current study, we found that the extract is involved in permeabilization of C. albicans cell membranes. While uptake of ethidium bromide (EtBr) was 3.0% in control cells, it increased to 7.4% for 30 min in the presence of the A. lappa ethanol extract at its minimal inhibitory concentration (MIC), 0.78 mg/ml, compared to uptake by heat-killed cells. Besides, leakage of DNA and proteins was observed in A. lappa-treated C. albicans cells. The increased uptake of EtBr and leakage of cellular materials suggest that A. lappa ethanol extract induced functional changes in C. albicans cell membranes. Incorporation of diphenylhexatriene (DPH) into membranes in the A. lappa-treated C. albicans cells at its MIC decreased to 84.8%, after 60 min of incubation, compared with that of the controls, indicate that there was a change in membrane dynamics. Moreover, the anticandidal effect of the A. lappa ethanol extract was enhanced at a growth temperature of 40℃ compared to that at 35℃. The above data suggest that the antifungal activity of the A. lappa ethanol extract against C. albicans is associated with synergistic action of membrane permeabilization due to changes in membrane dynamics and cell wall damage caused by reduced formation of (1,3)-β-D-glucan and chitin.

• Journal of Microbiology and Biotechnology
• /
• v.8 no.6
• /
• pp.705-709
• /
• 1998

In the course of screening for the substances suppressing bleb formation of K562 cell induced by phorbol 12, 13-dibutyrate (PDBu), an inhibitor, chaetoglobosin A (CgA) was isolated from a cultured broth of unidentified fungus. CgA showed a strong inhibitory activity with the $IC_{50}$ value of 60 pM against bleb formation on K562 cells induced by PDBu, but it did not inhibit the activity of protein kinase C (PKC) in vitro. The inhibitory activity of CgA might be due to the modulation of actin filaments on the cell membrane. CgA exhibited strong cytotoxicity against various human cancer cell lines.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.28 no.6
• /
• pp.413-420
• /
• 2002

Mercury is one of the most frequently used heavy metal in dental clinic. Mercury poisoning rises up when someone is exposed to mercury chronically. In 1818, Amalgam was used for dental restorative procedure, and after then study about mercury toxicity has begun. Clinical signs of mercury toxicity in oral & maxillofacial area were increases of salivation, metallic taste, swelling and pain of tongue, redness and ulceration of oral mucosa, and increased mobility and loss of teeth. After we injected mercury($HgCl_{2}$) into intraperitoneum of rat, studied about histopathological changes of submandibular gland cell. Experimental group was divided into two groups by amount of mercury. (Group 1 was 0.5mg/Kg of mercury injection, group 2 was 1.0mg/Kg of mercury injection.) 1. After 3days of intraperitoneal injection, black granules were observed at macrophage cell in both group. In group 2, author found hyperchromatism of nucleus, and vacuolization of cellular matrix and nucleus of acinar cell. 2. After 1week of intraperitoneal injection, author found severe vacuolization of nucleus and cellular matrix, and irregular granules around nuclear membrane at mucous cell and serous cell in both group. Vacuolization of nucleus and cellular matrix was seen at duct cell in group 2. 3. After 2weeks of intraperitoneal injection, author could found severe vacuolization of cellular matrix, and sometimes nucleus was positioned in central area of cellular matrix at mucous and serous cell in both group. Vacuolization of nucleus and cellular matrix was found at vascular endothelial cell in group 2. 4. After 4weeks of intraperitoneal injection, destruction and distortion of gland cells were distinct. Vacuolization and destruction of nucleus and cellular matrix was found at duct cell in group 2. After intraperitoneal injection of mercury, we found equanimity of mercury and destruction of cellular matrix at serous cell, mucous cell, and duct cell of submandibular gland. So, we thought that metallic taste of mercury poisoning patient would be due to excretion of saliva containing mercury.

• Proceedings of the Korean Society of Applied Pharmacology
• /
• 1996.04a
• /
• pp.173-173
• /
• 1996

포도당 수송을 증가시키는 것으로 밝혀진 brazilin의 작용이 지방세포의 단백질과 결합하여 나타나는지 알아보기 위한 실험으로 brazilin의 단백결합 성질을 살펴보았다. Brazilin의 단백결합 실험에는 [$^3$H]-brazilin을 사용하여 결합된 양을 방사선 동위원소량으로 확인하였다. 먼저 일반적인 단백결합을 알아보기 위하여 산침전을 이용한 brazilin의 BSA에 대한 결합을 살펴보았다. 그 결과 brazilin은 시간의 경과에 따라 BSA에 결합하는 양이 증가하여 2시간에 최고치에 달했으며 그 양은 약 80% 정도였다. 세포내 단백과의 결합은 BSA에 대한 결합과는 달리 1시간만에 최고치에 달하였다. 세포내 분획에 분포하는 brazilin의 양을 알기 위하여 brazilin처리 후 세포내 분획을 원심분리로 얻어 brazilin의 양을 확인하였다. 그 결과 brazilin은 cytosol에 대부분 존재하며 microsomal membrane과 nuclear에 많은 양이 존재하는 것으로 확인되었다. SDS-PAGE를 이용하여 brazilin과 결합한 각 분획의 단백질을 살펴본 결과 brazilin은 cytosol의 30, 65KD, microsomal membrane의 45, 130KD, nucear의 26, 35KD, plasma membrane의 46, 228KD protein과 반응하는 것으로 확인되었다.