• 한국광학회:학술대회논문집
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• 한국광학회 2007년도 하계학술발표회 논문집
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• pp.35-36
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• 2007

We report a probe using a single double clad fiber (DCF) for fluorescence spectroscopy. Bidirectional separate transmission for excitation and fluorescence light in a single fiber was implemented. A DCF coupler made by side-polished method could extract none but the collected fluorescence signals propagating in inner cladding mode, thereby diminishing the interference of silica background generated by the excitation in core mode. The experimental results show that the fluorescence spectra of biological tissues obtained using the DCF probes have much less silica background than using a standard multiple-mode fiber.

• Journal of the Optical Society of Korea
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• 제13권3호
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• pp.310-315
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• 2009

We report the fabrication of double clad fiber (DCF) and DCF coupler, suitable for fiber based imaging systems requiring the dual-channel transmission. Unlike the conventional DCF which uses silica for both cladding layers, the proposed DCF uses a low-index polymer for its outer-cladding layer coated over the conventional silica inner-cladding layer. The DCF is drawn with a conventional SMF preform but a low-index polymer coating is used for both jacket and outercladding of the fiber. To achieve the cladding mode coupling, a DCF coupler is fabricated by simply twisting two pieces of the proposed DCF after removing the polymer-coating at contacting regions. A cladding mode coupling ratio of 30% was achieved with a contact length of 16 cm. The proposed DCF and DCF coupler were employed in a composite optical coherence tomography (OCT) and fluorescence spectroscopy (FS) system, and both OCT images and FS signal from a plant tissue are measured simultaneously.

• Molecules and Cells
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• 제21권1호
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• pp.161-165
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• 2006

Dichlorodihydrofluorescein ($DCFH_2$) is a widely used probe for intracellular $H_2O_2$. However, $H_2O_2$ can oxidize $DCFH_2$ only in the presence of a catalyst, whose identity in cells has not been clearly defined. We compared the peroxidase activity of Cu,Zn-superoxide dismutase (CuZnSOD), cytochrome c, horseradish peroxidase (HRP), $Cu^{2+}$, and $Fe^{3+}$ under various conditions to identify an intracellular catalyst. Enormous increase by bicarbonate in the rate of $DCFH_2$ oxidation distinguished CuZnSOD from cytochrome c and HRP. Cyanide inhibited the reaction catalyzed by CuZnSOD but accelerated that by $Cu^{2+}$ and $Fe^{3+}$. Oxidation of $DCFH_2$ by $H_2O_2$ in the presence of a cell lysate was also enhanced by bicarbonate and inhibited by cyanide. Confocal microscopy of $H_2O_2$-treated cells showed enhanced DCF fluorescence in the presence of bicarbonate and attenuated fluorescence for the cells pre-incubated with KCN. Moreover, DCF fluorescence was intensified in CuZnSOD-transfected HaCaT and RAW 264.7 cells. We propose that CuZnSOD is a potential intracellular catalyst for the $H_2O_2$-dependent oxidation of $DCFH_2$.

• 약학회지
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• 제49권2호
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• pp.174-179
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• 2005

The human skin is constantly exposed to environmental irritants such as ultraviolet, smoke, chemicals. Free radicals and reactive oxygen species (ROS) caused by these environmen tal facts play critical roles in cellular damage. These irritants are in themselves damaging to the skin structure but they also participate the immensely complex inflammatory reaction. The purpose of this study was to investigate the skin cell protective effect of Campsis grandiflora extract on the UVB-irradiated human dermal fibroblasts (HDFs). We tested free radical and superoxide scavenging effect in vitro. C. grandiflora extracts had potent radical scavenging effect by 82% at $100{\mu}g/ml$, respectively. For testing intracellular ROS scavenging activity the cultured HDFs were analyzed by increase in DCF fluorescence upon exposure to UVB 20 $MJ/cm^2$ after treatment of C.grandiflora extracts. The results showed that oxidation of CM-DCFDA was inhibited by C.grandiflora extracts effectively and C.grandiflora extracts has a potent free radical scavenging activity in UVB- irradiated HDFs. In ROS imaging using confocal microscope we visualized DCF fluorescence in HDFs directly. In conclusion, our results suggest that C.grandiflora can be effectively used for the prevention of UV-induced adverse skin reactions such as radical production, and skin cell damage.

• 생명과학회지
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• 제27권7호
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• pp.796-804
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• 2017

본 연구는 어성초의 메탄올 추출물을 이용하여 항산화 효능이 가장 좋은 fraction을 찾고, 항산화 효능을 나타내는 성분을 분석하였다. 메탄올 추출에 의한 유기 용매 별 분획에서 항산화 효과가 가장 좋은 ethyl acetate 분획물을 칼럼 크로마토그래피하여 12가지의 fraction 중 가장 높은 항산화 효과를 보인 Fr. 10을 이용하여 DPPH 라디칼의 소거활성, 환원력, 지질과산화, 세포독성, DNA 산화 및 DCFH-DA를 이용한 세포내 과산화수소 제거효과를 조사하였다. DPPH radical scavenging activity, reducing power, TBARS, cell viability, DNA oxidation and DCF fluorescence 12가지의 fraction들 중 항산화 효능이 가장 좋은 Fr. 10의 DPPH radical 소거 활성 결과로 $64{\mu}g/ml$ 농도에서 양성대조군에 근접하는 60%의 억제능을 보였다. Reducing power 결과로 $32{\mu}g/ml$의 농도에서 140%로 양성대조군과 비슷한 결과 값을 보였다. TBARS 결과로 $2{\mu}g/ml$에서 양성대조군과 같은 값의 활성산소 억제능이 나타난다. 또한 cell viability 결과로 $32{\mu}g/ml$ 이상의 농도에서 세포 독성에 의해 생존율이 감소하였고, DCF fluorescence 결과로 농도의존적으로 $H_2O_2$에 의한 산화적 손상을 억제하는 것으로 나타났다. DNA oxidation 실험결과 $1{\mu}g/ml$ 이상의 농도에서 DNA의 손상을 감소시킴을 확인할 수 있었다. IR 및 LC-MS를 이용하여 Fr. 10의 유효성분을 조사한 결과 rutin (분자량, 610)으로 확인 되었다. 결론적으로 어성초의 메탄올 추출물로부터 분리한 Fr. 10은 농도 의존적으로 항산화 효능이 우수하게 나타났고, 어성초는 화장품 및 기능성 식품의 소재로 활용될 수 있음을 시사한다.

• 대한약침학회지
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• 제10권3호
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• pp.53-62
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• 2007

Objective The objective of this study was to investigate the antioxidative effects of Puerariae Radix extract. Method Total antioxidant capacity (TAC), Total antioxidant response (TAR), Total phenolic content, Reactive oxygen species (ROS), 1,1-Diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activities, lipid peroxidation were examined. Result Total antioxidant status was examined by total antioxidant capacity(TAC) and total antioxidant response(TAR) against potent free radical reactions. TAC and TAR of Puerariae Radix extract at the concentration of 5 mg/ml were 2.02 and 1.50 mM Trolox equivalents, respectively. Total phenolic content of Puerariae Radix extract at the concentration of 5 mg/ml was 2.29 mM gallic acid equivalent. Concentration of Puerariae Radix extract at which DPPH radical scavenging activity was inhibited by 50% was 5.91 mg/ml as compared to 100% by pyrogallol solution as a reference. The inhibitory effect of the extract on lipid peroxidation was examined using rat liver mitochondria induced by FeSO4/ascorbic acid. Puerariae Radix extract at the concentration of 1 mg/ml slightly but significantly decreased TBARS concentration. The extract further prevented lipid peroxidation in a dose-dependent manner. The effect of Puerariae Radix extract on reactive oxygen species (ROS) generation was examined using cell-free system induced by hydrogen peroxide/FeSO4. Addition of 1 mg/ml of Puerariae Radix extract significantly reduced dichloroflurescein (DCF) fluorescence. The extract caused concentration-dependent attenuation of the increase in DCF fluorescence, indicating that the extract significantly prevented ROS generation in vitro. Thus antioxidant effects of Puerariae Radix extract seem to be due to, at least in part, the prevention from free radicals-induced oxidation, followed by inhibition of lipid peroxidation. Conclusion As a result, Puerariae Radix seems to have antioxitative effect and antioxidant compount.

• 대한약침학회지
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• 제11권3호
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• pp.67-78
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• 2008

Objective: The objective of this study was to compare the antioxidant effects among wild ginseng, cultivated wild ginseng, and ginseng extracts. Methods: In vitro antioxidant activities were examined by total antioxidant capacity (TAC), oxygen radical scavenging capacity(ORAC), total phenolic content, 1, 1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, inhibition of induced lipid peroxidation using liver mitochondria, reactive oxygen species(ROS) scavenging effect using 2', 7'-dichlorofluorescein(DCF) fluorescence. Results: 1. TAC of 1.5 and 3.75 mg extracts was highest in cultivated wild ginseng, followed by wild ginseng and lowest in ginseng. 2. ORAC of 2, 10, and $20{\mu}g$ extracts was highest in cultivated wild ginseng, followed by wild ginseng and lowest in ginseng. 3. Total phenolic content of 0.375, 0.938, and 1.875 mg extracts was highest in cultivated wild ginseng, followed by wild ginseng and lowest in ginseng. 4. DPPH(1, 1 -Diphenyl-2-picrylhydrazyl) scavenging activity between wild ginseng and cultivated wild ginseng did not differ significantly (p>0.05). 5. Induced lipid peroxidation, measured by TBARS concentration in solution containing rat liver mitochondria incubated in the presence of $FeSO_4$/ascorbic acid was inhibited as amounts of wild ginseng, cultivated wild ginseng, and ginseng extracts increased. TBARS concentration of ginseng extracts were significantly (p<0.05) higher than wild ginseng or cultivated wild ginseng extracts. 6. DCF fluorescence intensity was decreased as concentrations of wild ginseng, cultivated wild ginseng, and ginseng extracts increased, demonstrating that ROS generation was inhibited in a concentrationdependent manner. Conclusions: In summary, the results of this study demonstrate that cultivated wild ginseng extracts had similar antioxidant activities to wild ginseng extracts and greater that of cultivated ginseng extracts.

• 한국자원식물학회지
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• 제19권6호
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• pp.649-654
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• 2006

The objective of present study was to investigate the anti oxidative and hepatoprotective effects of tomato extracts. Total antioxidant capacity and total antioxidant response were 5.5 and $19.8{\mu}g$ Trolox equivalent per mg of tomato extract, respectively. DPPH radical scavenging activity of tomato extracts ($10mg\;ml^{-1}$) was 70% as compared to 100% by pyrogallol solution as a reference. The effect of the tomato extracts on lipid peroxidation was examined using rat liver mitochondria induced by iron/ascorbate. Tomato extracts at the concentration of $0.5mg\;ml^{-1}$ significantly decreased TBARS concentration. Tomato extracts prevented lipid peroxidation in a dose-dependent manner. The effect of the tomato extracts on reactive oxygen species (ROS) generation was examined using cell-free system induced by $H_2O_2/FeSO_4$. Addition of $1mg\;ml^{-1}$ of tomato extracts significantly reduced dichlorofluorescein (DCF) fluorescence. Tomato extracts caused concentration-dependent attenuation of the increase in DCF fluorescence, indicating that tomato extracts significantly prevented ROS generation in vitro. The effect of tomato extracts on cell viability and proliferation was examined using hepatocyte culture. Primary cultures of rat hepatocytes were incubated with 1mM tert-butyl hydroperoxide (t-BHP) for 90 min in the presence or absence of tomato extracts. MTT values by addition of tomato extracts at the concentration of 2, 10, and $20mg\;ml^{-1}$ in the presence of t-BHP were 13, 33 and 48%, respectively, compared to 100% as control. Tomato extracts increased cell viability in a dose-dependent manner. These results demonstrate that tomato extracts suppressed lipid peroxidation and t-BHP-induced hepatotoxicity and scavenged ROS generation. Thus antioxidant and hepatoprotective effects of tomato extracts seem to be due to, at least in part, the prevention from free radicals-induced oxidation, followed by inhibition of lipid peroxidation.

• 대한한의학회지
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• 제28권1호통권69호
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• pp.137-147
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• 2007

Objective : The objective of this study was to investigate the antioxidative effects of Carthami Flos extract. Methods : Total antioxidant status was examined by total antioxidant capacity(TAC) and total antioxidant response(TAR) against potent free radical reactions. The effect of Carthami Flos extract was examined far details of total phenolic content concentration at which 1,1-dipheny1-2-picrylhydrazyl(DPPH) radical scavenging activity was inhibited, the inhibitory effect on lipid peroxidation, and the effect on reactive oxygen species(ROS) generation. Results : TAC of Carthami Flos extract at the concentration of 5 mg/ml was 1.84 mM Trolox equivalent. 2. TAR of Carthami Flos extract, on the other hand, couldn't be determined due to interference from unidentified compounds. 3. Total phenolic content of Carthami Flos extract at the concentration of 5 mg/ml was 2.01 mM gallic acid equivalent. 4. Concentration of Carthami Flos extract at which DPPH radical scavenging activity was inhibited by 50% was 6.43 mg/ml as compared to 100% by Pyrogallol solution as a reference. 5. The inhibitory effect of the extract on lipid peroxidation was examined using rat liver mitochondria induced by FeS04/ascorbic acid. Carthami Flos extract at the concentration of 10 ms/ml slightly but significantly decreased TBARS concentration. The extract continued to prevent lipid peroxidation in a dose-dependent manner. 6. The effect of Carthami Flos extract on reactive oxygen species(ROS) generation was examined using a cell-free system induced by hydrogen peroxide/FeS04. Addition of 1 mg/ml of Carthami Flos extract significantly reduced dichlorofluorescein(DCF) fluorescence. Carthami Flos extract caused concentration-dependent attenuation of the increase in DCF fluorescence, indicating that the ektract significantly prevented ROS generation in vitro. Conclusion: : Antioxidant efffcts of Carffami ffor extract seem to be due, at least in part, to the prevention offree radical-induced oxidation, fellowed by inhibition of lipid peroxidation.

• 대한한의학회지
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• 제28권1호통권69호
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• pp.148-158
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• 2007

Objective : The objective of this study was to investigate the antioxidant effects of Mori Folium extract. Methods Total antioxidant status was examined by total antioxidant capacity(TAC) and total antioxidant response(TAR) against potent free radical reactions. The effect of Mori Folium extract was examined by measuring total phenolic content, concentration at which 1,1-dipheny1-2-picrylhydrazyl(DPPH) radical scavenging activity was inhibited, inhibitory effect on lipid peroxidation, and the effect on reactive oxygen species(ROS) generation. Results : 1. TAC and TAR of Mori Folium extract at the concentration of 5 mg/ml were 1.61 and 1.24 mM Trolox equivalents, respectively. 2. Total phenolic content of Mori Folium extract at the concentration of 5 mg/Ml was 1.70 mM gallic acid equivalent. 3. Concentration of Mori Folium extract at which DPPH radical scavenging activity was inhibited by 50% was 2.29 m9/m4 as compared to 100% by Pyrogallol solution as a reference. 4. The inhibitory effect of the extract on lipid peroxidation was examined using rat liver mitochondria induced by FeSO$_4$/ascorbic acid. Mori Folium extract at the concentration of 10 mg/ml significantly decreased thiobarbituric acid reactive substances(TBARS) concentration. The extract prevented lipid peroxidation in a dose-dependent 5. The effect of Mori Folium extract on reactive oxygen species(ROS) generation was examined using a celt-free system induced by hydrogen peroxide FeSO$_4$. Addition of 1 mg/ml of Mori Folium extract significantly reduced dichlorofluorescein(DCf) fluorescence. The extract caused concentration-dependent attenuation of the increase in DCF fluorescence, indicating that the extract significantly prevented ROS generation in vitro. Conclusion ; The antioxidant effects of Mori Folium extract seem to be due, at least in part, to the prevention offree radical-induced oxidation, fllowed by inhibition of lipid peroxidation.