• 대한화학회지
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• 제46권5호
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• pp.444-456
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• 2002

차체의 산화를 방지하기 위하여 희생적 양극을 사용한 산화방지 장치를 개발하였다. 희생적 양극은 철보다 산화 전위가 높은 Mg, Al, Zn으로 만들어 졌고 이것은 차체의 철이나 철합금보다 먼저 산화되어 차체의 부식을 방지한다. 차체 산화방지 장치를 제작하여 철시편을 염산, 질산 및 황산에 대한 방식효과를 시간에 따라 측정하였고 SEM과 XPS를 이용하여 철시편 표면의 방식효과를 분석하였다. 철시편을 산화 방지 장치에 연결하면 산화되어 산성용액 속으로 녹아 들어가는 철의 양이 현저하게 감소하고 철시편 표면의 산화가 방지되며 산화된 철은 $Fe_2O_3$의 산화형태를 가짐을 확인하였다. 따라서 차체 산화방지를 차체에 직접 부착한다면 차체의 부식 및 산화를 효과적으로 방지할 것으로 기대된다.

• Restorative Dentistry and Endodontics
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• 제39권2호
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• pp.95-103
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• 2014

Objectives: This study evaluated the effect of three antioxidizing agents on pullout bond strengths of dentin treated with sodium hypochlorite. Materials and Methods: Root canals of 75 single-rooted human teeth were prepared. Fifteen teeth were irrigated with normal saline for a negative control group, and the remaining 60 teeth (groups 2 - 5) with 2.5% NaOCl. The teeth in group 2 served as a positive control. Prior to post cementation, the root canals in groups 3 - 5 were irrigated with three antioxidizing agents including 10% rosmarinic acid (RA, Baridge essence), 10% hesperidin (HPN, Sigma), and 10% sodium ascorbate hydrogel (SA, AppliChem). Seventy-five spreaders (#55, taper .02, Produits Dentaires S.A) were coated with silica and silanized with the Rocatec system and ceramic bond. All the prepared spreaders were cemented with a self-adhesive resin cement (Bifix SE, Voco Gmbh) in the prepared canals. After storage in distilled water (24 h/$37^{\circ}C$), the spreaders were pulled out in a universal testing machine at a crosshead speed of 1.0 mm/min. Pull-out strength values were analyzed by one-way ANOVA and Tukey's HSD test (${\alpha}$ = 0.05). Results: There were significant differences between study groups (p = 0.016). The highest pullout strength was related to the SA group. The lowest strength was obtained in the positive control group. Conclusions: Irrigation with NaOCl during canal preparation decreased bond strength of resin cement to root dentin. Amongst the antioxidants tested, SA had superior results in reversing the diminishing effect of NaOCl irrigation on the bond strength to root dentin.

• Ocean and Polar Research
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• 제25권1호
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• pp.129-132
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• 2003

The crude extracts of marine algae were screened for tyrosinase-inhibitory and radical scavenging effects. Among the samples tested, Symphyocladia latiuscula and Gloiopeltis furcata were found to be the most effective in DPPH radical scavenging test while Gigatina tenella, Sargassum thunbergii, and Sargassum sp. were moderately active. For the inhibition against mushroom tyrosinase, Symphyocladia latiuscula and Sargassum confusum showed the strongest inhibition. Codium adhaerens, Corallina pilulifera, Carpopeltis cornea, Halymenia acuminata, Hizikia fuziformis, Porphyra suborbiculata, and Enteromorpha linza exhibited mild inhibitory potency.

• 한국수산과학회지
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• 제27권2호
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• pp.155-165
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• 1994

To evaluate the antioxidant effect of flavonoids and a-tocopherol on purified fish oil(up to $40\%$ of n-3 polyunsaturated fatty acids), lipid peroxidation, and fatty acids content during storage and upon heating were determined. The potential of these compounds for inhibiting and delaying both oxidation and lipoxygenase processes was also evaluated. The oxidation of fish oil was effectively inhibited by flavonoids and a-tocopherol. The antioxidizing effect of these compounds increased in proportion to their concentration. The addition of a-tocopherol and catechin-a-tocopherol mixture were prolonged induction period of lipid oxidation by 3.5 to 4 times. All other flavonoids also shown more than twice the prolonging effect. Lipoxygenase activity was decreased by catechin and a-tocopherol effectively.

• 대한예방한의학회지
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• 제12권3호
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• pp.47-58
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• 2008

The anticancer and antioxidant effect of different lengths of saturated fatty acids was tested on NIH3T3 fibroblasts and human skin melanoma cellsn in this study. The cell existence rate and antioxidizing capacity and optic reservation of cells were observed. This saturated fatty acid was concentration-dependent. IC50 Concentrations in NIH3T3 fibroblasts, human skin melanoma cells and DPPH radical scavenging activity of fatty acid was increasing the order of carbochain length ; caprylic acid < lauric acid < palmitic acid < stearic acid. The reduction in cell number and morphological change in human skin melanoma cells was increasing the order of carbochain length ; caprylic acid < lauric acid < palmitic acid < stearic acid. These results suggest that carbochain length of fatty acid can be used as structure-activity relationships for anticancer and antioxidant.

• 통합자연과학논문집
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• 제5권1호
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• pp.46-52
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• 2012

Mulberry extracts can be incorporated into skin-whitening products. The compound attributed to lighten the skin is arbutin, a form of hydroquinone that inhibits melanin release by suppressing the tyrosinase enzyme. For the cosmetic applications, the physiological effects of mulberry (Morus alba) extracts were investigated. The water soluble fraction of mulberry contains higher amount of protein (16.28~4.47%) in contrast to fat (1.55~1.41%). In addition, the fraction abundantly contains succinic acid (972.4-275.8 mg/g) and phosphoric acid (1,628.4-121.9 mg/g) in different parts of mulberry. The free radical scavenging ability in water soluble fraction was found to display remarkable effects in comparison with methanol and ethyl acetate fraction. The ethyl acetate-soluble of root and leaf showed remarkable tyrosinase inhibition activity by IC 50 (${\mu}g/ml$). The anticancer activity of methanol fraction obtained from mulberry using human cancer cell lines showed growth inhibition effect (270.14 mg/ml in Calu-6 cells, 295.29 mg/ml in HCT-116, and 332.29 mg/ml in MCF-7 cells, respectively). Based on the results, Morus alba extracts include cosmetic ingredients with antioxidizing and whitening properties.

• 대한화학회지
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• 제54권6호
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• pp.707-710
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• 2010

우리나라 서남단의 지리산에는 천연야생에서 자생하는 한방약초의 보고라고 할 수 있다. 현재 약초로 분류되는 식물로는 1200여종이 자생 혹은 재배되고 있다. 최근들어 이들 중 현대인의 피부노화억제와 관련하여 관심을 끌고 있는 약초로 홍화에 관한 연구가 활발히 연구되고 있는데 금번연구에서는 홍화의 주성분인 폴리페놀 화합물(Polyphenol cocktail)이 30 - 40대 중년기의 여성에게 주름생성을 억제시켜 피부노화에 대한 지연효과를 줄 수 있는 천연물질임을 확인하고자 한다. 본 연구에서는 1차적으로 in vitro법으로 DPPH assay로 항산화효과를 확인하고 더불어 인체에 대한 임상시험을 통해 얼굴피부의 주름발생에 대한 억제 혹은 개선효과가 있음을 입증하고자 한다. 또한 홍화추출물을 주성분으로 하는 항노화 마스크팩 시제품의 개발로 진일보하여 기능성화장품 산업의 발전에 기여할 것임을 확신한다.

• 약학회지
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• 제47권5호
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• pp.311-318
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• 2003

Eurya emarginata (Thunb.) Makino (Theaceae) is distributed in coastal areas of island. The leaves of Eurya are used in the traditional medicine of the coastal areas of jeju island with the aim of diuresis or to treat ulcers. Nevertheless, there are few reports on the biological activity and constituents of E. emarginata. In this study, we investigated the pharmacological activity of the solvent extracts of E. emarginata on the several inflammatory markers (TNF-$\alpha$, IL-1$\beta$, IL-6, NO, iNOS and COX-2). Also we examined the antioxidizing effect of the solvent extracts by determination of DPPH radical-scavenging activity. Among the solvent fractions, EtOAc and BuOH extracts showed potent radical scavenging activity (RC$_{50}$=10.9 and 12.7 respectively). The subtractions of EF 5-4-6-3-2 and BF 1 potentially inhibited the mRNA expression of pro-inflammatory cytokines (IL-1$\beta$, IL-6 and TNF-$\alpha$) at the concentration of 100 $\mu\textrm{g}$/mι. Also the fractions inhibited the mRNA expression of pro-inflammatory cytokines (IL-1$\beta$, IL-6 and TNF-$\alpha$) and protein expression of iNOS and COX-2 at the concentration of 100 $\mu\textrm{g}$/mι. And then, the inhibition of iNOS was correlated with the decrease of nitrite level. These results suggest that E. emarginata may have anti-inflammatory activity through the inhibition of pro-inflammatory cytokines, iNOS and COX-2.2.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2003년도 제10차 국제학술회의 및 추계정기 학술발표회
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• pp.48-49
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• 2003

This project was conducted to development several camellia tea mixed herb teas having any physiological effects. Leaves of tea tree contain many compounds, such as polysaccharides, volatile oils, vitamins, minerals, purines, alkaloids(eg. caffeine) and polyphenols(catechins and flavonoids). Although all three tea types(green, oolonr and black) have antibacterial and free radical capturing(antioxidizing) activities, the efficacy decreases substantially the darker the variety of tea is. This is due to lower contents of anti-oxidizing polyphenols remaining in the leaves. Unlike tea tree(Camellia sinensis), the biochemical features and effects of camellia(Camellia japonica) are not well known. Fresh mature leaf of sasanqua camellia(C. sasanqua), roasted young leaf tea(C. japonica) and fresh mature leaf and bark of camellia had high antibacterial activity against P. vulgaris and B. subtilis. In antifungal activity bioassay, young leaf roasted teas of camellia and sasanqua camellia had high activity against C. albicans and T. beigelil. Plant extracts from Camelia japonica had higher inhibitory activity against fungi than against bacteria. In cytotoxic effect against human acute myelogenous leukaemia cell extracts including fresh leaf(200$\mu\textrm{g}$/m1), bark(230$\mu\textrm{g}$/ml) and flower tea (320$\mu\textrm{g}$/m1)inhibited growth of AML cells.(중략)

• KSBB Journal
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• 제19권1호
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• pp.57-61
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• 2004

본 연구에서는 항산화 활성을 갖는 유용한 선도 물질을 찾기 위한 일환으로 20종의 염생식물의 추출물에 대해 peroxynitrite와 DPPH 라디칼 소거 활성을 측정하였다. 그 결과 해당화 (Rosa rugosa), 개망초 (Erigeron annus), 냇씀바귀(Ixeris tamagawaensis), 띠 (Imperata cylindrica), 범행초(Tetragonia tetragonoides), 사철쑥 (Artemisia capillaris)의 MeOH 추출물에서 우수한 DPPH 라디칼 소거 효과가 확인되었다. 또한, 해당화(Rosa rugosa), 개망초 (Erigeron annus), 칠면초 (Suaeda japonica), 냇씀바귀 (Ixeris tamagawaensis), 띠 (Imperata cylindrica), 갯방풍 (Glehnia littoralis), 함초(Salicornia herbacea), 해국 (Aster spathulifolius), 범행초 (Tetragonia tetragonoides)의 MeOH 추출물과 CH$_2$Cl$_2$ 추출물에서 각각 peroxynitrite의 소거효과가 관찰되었다. 그 중에서도 해당화 MeOH 추출물의 DPPH 래디칼 소거효과는 100 $\mu\textrm{g}$/$m\ell$ (f.c.) 농도에서 87.51%로 나타났고, peroxynitrite 소거효과는 5 $\mu\textrm{g}$/$m\ell$ 농도에서 표품의 ONOO를 첨가했을 때 97.03%와 SIN-1을 첨가했을 때 98.48%로서 가장 강력한 항산화활성을 가지는 것으로 나타났다. 해당화의 peroxynitrite의 효과는 대조군으로 사용된 penicillamine보다도 우수하며, L-ascorbic acid와 비슷한 효과였다.