• Journal of Applied Biological Chemistry
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• 제60권2호
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• pp.185-190
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• 2017

백연수 잎으로부터 얻어진 50% 에탄올 추출물의 항산화능을 조사하였다. 백연수 잎 추출물의 수율은 $18.3{\pm}0.40%$, 총 폴리페놀 함량은 $121.3{\pm}11.04{\mu}g$ gallic acid equivalents/mg, 총 플라보노이드 함량은 $105.2{\pm}2.77{\mu}g$ quercetin equivalents/mg으로 나타났다. 백연수 잎 추출물은 유리라디칼 소거활성, 양이온라디칼 소거활성, 아질산염 소거활성, 환원력 및 지질과산화 억제 활성의 항산화능을 가지고 있었다. 백연수 잎 추출물의 모든 항산화 활성은 추출물의 농도에 비례하여 증가하였으며, 유리라디칼 소거활성, 양이온라디칼 소거활성, 아질산염 소거활성 및 환원력의 $EC_{50}$은 각각 133.51, 667.22, 2.58 및 $250.00{\mu}g/mL$이었다. 백연수 잎의 우수한 항산화 활성은 높은 폴리페놀과 플라보노이드 함량에 기인한 것으로 여겨진다.

• 한국식품조리과학회지
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• 제32권3호
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• pp.299-306
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• 2016

Purpose: Curcuma aromatica Salisb., commonly known as turmeric, has long been used as a powerful health-promoting anti-inflammatory or antioxidant that supports cellular health of the human body. The objective of this study was to compare the antioxidant and antimicrobial activities of the samples with or without fermentation. Methods: Antioxidant activities of the samples were compared using total phenol, flavonoid contents, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) cation radical scavenging activity and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. Antimicrobial activities were also examined using the paper disc method and minimum inhibitory concentration (MIC). Results: Organic acid content of the C. aromatica Salisb. fermented with Aspergillus oryzae (FCAS) showed a significantly higher value of 0.41% than that of the typical sample without fermentation (CAS) which showed a value of 0.27% (p<0.001). Total phenol and flavonoid contents of the CAS and FCAS did not show significant differences. However, ABTS cation radical scavenging activity and DPPH radical scavenging activity were significantly increased in the samples with fermentation (p<0.001, p<0.01), respectively. The samples of the disc showed inhibited growth of gram positive Bacillus cereus (FCAS 3.70 cm and CAS 2.73 cm) and Staphylococcus aureus (FCAS 2.70 cm and CAS 1.97 cm). MIC of the FCAS (0.25-0.50, 0.5-1.00 mg/mL) was higher than that of the CAS (1.00-2.00, 2.00-3.00 mg/mL), respectively. Conclusion: C. aromatica Salisb. with fermentation showed higher antioxidant and antimicrobial activities in this study. Thus we conclude that fermentation can be a helpful process for more effective application of C. aromatica Salisb. with fermentation in the health-promoting food industry.

• Journal of Applied Biological Chemistry
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• 제62권2호
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• pp.167-172
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• 2019

Napier grass (Penninsetum purpureum)의 50% 에탄올 추출물의 수율, 폴리페놀 함량 및 항산화 활성을 확인하였다. Napier grass 추출물의 수율은 $6.3{\pm}0.35%$이었고, 총 페놀성 화합물 함량은 $79.6{\pm}3.65{\mu}g$ gallic acid equivalents/mg-추출물로 나타났다. Napier grass 추출물의 유리라디칼과 양이온라디칼 소거능, 환원력, 아질산염 소거능 및 지질과산화 억제능은 모두 추출물의 농도에 비례하여 증가하였다. Napier grass 추출물의 DPPH 유리라디칼에 대한 $EC_{50}$값은 $1,930.0{\mu}g/mL$로 유리라디칼에 대한 소거활성이 높지 않았다. Napier grass 추출물의 ABTS 양이온라디칼 소거, 환원력 및 아질산염 소거에 대한 $EC_{50}$값은 각각 350.0, 840.0 및 $1,470.0{\mu}g/mL$로 나타나 유리라디칼 소거활성에 비해 높은 항산화 능력을 보유하고 있었다. 특히 Napier grass 추출물은 $85.0{\mu}g/mL$의 농도에서 과산화물의 생성을 74.6% 억제할 정도로 뛰어난 지질과산화 억제활성을 보여주었다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2019년도 춘계학술대회
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• pp.105-105
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• 2019

Dendropanax morbifera H.Lev is an evergreen tree that lives in subtropical climates. About 75 species of D. morbifera live in East Asia, but only one species live in Korea(Korean dendropanax). D. morbifera belonging to Aralicacae family 98% of D. morbifera are distributed in Jeollanam-do in the Korea and the grow wild in Gyeongsangnam-do and Jeju Island. The harvest time and usage of D. morbifera were recorded in traditional medicinal books. The roots and stems of D. morbifera had been used for traditional medicine to treat migraine, menstrual irregularity and skin disease. And D. morbifera leaves are contain flavonoids and polyacetylene compounds. In this study, we were investigated the physiological activity of D. morbifera by different areas collected at the same time, and compared to characteristics of plants. D. morbifera collected from Jeollanam-do (Goheung-gun), Gyeongsangnam-do (Namhae-gun) and Jeju Island, and dried at $50^{\circ}C$ for three days. We used dried D. morbifera powder for antioxidant tests. Each sample was extracted with hot water under the same conditions. The contents of total polyphenols and total flavonoids from D. morbifera were identified. Also, we performed to DPPH radical scavenging activity, ABTS cation radical scavenging activity and Superoxide anion scavenging activity efficacy for antioxidant activity determination. The contents of total polyphenols and total flavonoids in hot water extract of D. morbifera harvested from Gyeongsangnam-do and Jeollanam-do were higher than Jeju. However, D. morbifera harvested from Gyeongsangnam-do and Jeollanam-do showed no significant difference those content of total polyphenols and total flavonoids. And the antioxidant capacity was showed the similar patterns in antioxidant activity.

• 대한화학회지
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• 제40권8호
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• pp.34-585
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• 1996

• 대한화학회지
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• 제8권1호
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• pp.25-29
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• 1964

Benzhydryl azide 類에 Benzhydrol 類를 混合하여 Schmidt 反應을 逐行할 때에 Benzhydryl 基 間에 完全한 Radical exchange 現象이 일어남을 알았다. 故로 Benzhydrol 類의 Schmidt 反應에 있어서는 一但 生成된 Benzhydryl azide가 濃硫酸存在下에서 Benzhydryl cation과 Hydrazoic acid로 分離되어 完全平衡狀態에 있음을 確認할 수 있었다.

• 한국광학회:학술대회논문집
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• 한국광학회 2008년도 동계학술발표회 논문집
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• pp.319-320
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• 2008

• Journal of Applied Biological Chemistry
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• 제43권3호
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• pp.156-160
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• 2000

The possible mechanism of the DNA strand breaking activity of the hot-water extract of Fructus Chaenomelis (dried fruit of Chaenomeles sinensis) in a closed circular duplex replica form DNA (RFI DNA) was studied through agarose gel electrophresis under various conditions. Induction of DNA strand scission by the hot-water extract of C. sinensis occurred in dose and time-dependent manners. $Cu^{2+}$ was indispensable for the induction of DNA strand breakage. Exogeneous chelating agents inhibited the DNA breaking activity, conforming the catalytic action of $Cu^{2+}$ on generation of free radicals responsible for oxidative damage. Antioxidant enzymes and some radical scavengers were used to investigate the major radical species triggering the DNA strand scission, demonstrating that a highest inhibitory activity was found in the presence of catalase, while less in the presence of tiron (a scavenger for superoxide radical), 2-aminoethyl-isothiuroniumbromide-HBr, cysteamine (scavengers for hydroxyl radical), and 1,4-diazabicyclo [2,2,2] octane (a scavenger for singlet oxygen) in decreasing order. The findings implied that oxygen radical species generated in presence of transition divalent cation during the oxidation of some compounds contained in the hot-water extract of C. sinensis is mainly responsible for inducing genotoxicity.

• Journal of Electrochemical Science and Technology
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• 제4권2호
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• pp.71-80
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• 2013

The study of methyl viologen ($MV^{2+}$) mediated oxygen reduction in electrolytic ethanol media possesses potential application in the electrochemical synthesis of hydrogen peroxide mainly due to the advantages of the much increased solubility of molecular oxygen ($O_2$) and high degree of reversibility of $MV^{2+/{\bullet}+}$ redox couple. The diffusion coefficients of both $MV^{2+}$ and $O_2$ were investigated via electrochemical techniques. For the first time, $MV^{2+}$ mediated $O_2$ reduction in electrolytic ethanol solution has been proved to be feasible on both boron-doped diamond and micro-carbon disc electrodes. The electrocatalytic response is demonstrated to be due to the radical cation, $MV^{{\bullet}+}$. The homogeneous electron transfer step is suggested to be the rate determining step with a rate constant of $(1{\pm}0.1){\times}10^5M^{-1}s^{-1}$. With the aid of a simulation program describing the EC' mechanism, by increasing the concentration ratio of $MV^{2+}$ to $O_2$ electrochemical catalysis can be switched from a partial to a 'total catalysis' regime.

• 대한화학회지
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• 제40권11호
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• pp.686-691
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• 1996

Viologen 유도체를 합성하여 이들의 electrochromic(전기변색) 특성을 조사했다. 1, 1'-diethyl-4, 4'-bipiridinium dibromide(EV), 1, 1'-dipropyl-4, 4'-bipyridinium dibromide(PV), 1, 1'-dibuthyl-4, 4'-pyridinium dibromide(BV), 1-ethyl-1'-butyl-4, 4'-bipyridinium dibromide(EBV)를 대상으로 하여 propylene carbonate/methanol 용액내에서 전기변색성을 검토하였다. 또한 전장하에서 EV와 EBV의 cation radical은 dimer를 형성하는 것을 알 수 있었다.