• Journal of Microbiology and Biotechnology
• /
• 제9권6호
• /
• pp.732-736
• /
• 1999

The superoxide dismutase (SOD) in Lactococcus lactis was measured quantitatively and qualitatively under various culture conditions. The L. lactis SOD was induced by oxidative stress. As the concentration of paraquat to produce superoxide radicals increased, the growth of L. lactis decreased with concomitant increase of SOD activity. The SOD activity was found to be growth-phase dependent: when aerobically grown cells entered to the stationary phase, the activity increased gradually until the late stationary phase. From inhibition studies, L. lactis SOD was found to be insensitive to KCN and $H_2O_2$ which are known to inhibit Cu/ZnSOD and FeSOD, respectively. Moreover, as the concentration of manganese in the medium increased, the activity of SOD also increased. These data strongly suggested that L. lactis possessed a single manganese-containing SOD (MnSOD). Finally, a putative sod gene fragment of 510 bp was identified in L. lactis using a polymerase chain reaction (PCR) with degenerate primers designed from the deduced DNA sequences of known SOD genes.

• Archives of Pharmacal Research
• /
• 제28권1호
• /
• pp.22-27
• /
• 2005

Bioassay-guided fractionation of methanol extract of Reynoutria sachalinensis flower using DPPH assay has led to the isolation of three anthraquinones and three flavonoids. Their structures were identified as emodin (1), emodin-8-O-$\beta$-D-glucopyranoside (2), physcion-8-O-$\beta$-D­glucopyranoside (3), quercetin-3-O-$\alpha$-L-arabinofuranoside (4), quercetin-3-O-$\beta$-D-galactopyra­noside (5), and quercetin-3-O-$\beta$-D-glucuronopyranoside (6) by comparing their physicochemical and spectral data with those published in literatures. All isolated compounds were evaluated for antioxidant activities with free radical 1, 1-diphenyl-2-picrylhydrazyl (DPPH) scavenging, superoxide radical scavenging and $Cu^{2+}$-mediated low density lipoprotein (LDL) oxidation assay. The results demonstrated that three flavonoids, 4, 5, and 6 had remarkable antioxidant activities with the $IC_{50}$ values of 64.3, 54.7, and 46.2${\mu}M$ (DPPH scavenging), the $IC_{50}$ values of 6.0, 6.7, and $4.4{\mu}M$ (superoxide radical scavenging) and the $IC_{50}$ values of 3.8, 3.2, and 5.4${\mu}M$ against LDL oxidation, respectively.

• 생명과학회지
• /
• 제17권2호통권82호
• /
• pp.230-234
• /
• 2007

생체는 산소를 소비하는 대사 과정 중에 초산화물(superoxide, $O_{2}$), 과산화수소($H_2O_2$), 수산 라디칼(OH)과 같은 다양한 활성산소(reactive oxygen)들을 생성하게 되며, 그 중에서도 hydrogen peroxide ($H_2O_2$)는 biological membrane을 자유롭게 통과하며, 세포내에서 hydroxyl radical 등의 반응성이 큰 활성 산소종(reactive oxygen species, ROS)을 발생시키는 작용을 하는 강력한 산화제이다. 세포를 계대 배양 (5, 15, 25, 35 passage)하여 $H_2O_2$를 농도별(100 ${\mu}M$, 500 ${\mu}M$, 1 mM, 5 mM)로 처리하고, 또한 $H_2O_2$의 처리 시간(30 분, 1 시간)을 변화시킴으로써, Hepatoma 세포주에서 $H_2O_2$ 처리에 의한 Cu/Zn SOD의 발현을 Northern blot을 통하여 다음과 같이 분석하였다. 1)Hepatoma 세포주에서 시간별, 농도별로 산화제를 처리 했을 때 각각의 경우에서 발현양의 차이는 적었지만, 오랜 시간동안 고농도의 산화제에 노출시켰을 때 항산화 능력이 증가한다는 것을 확인할 수 있었다. 2)계대배양을 증가시키는 것은 노화가 진행된다는 것을 의미하므로, 산화제를 처리했을 때 25 passage에서 35 passage 단계에서 항산화 효소의 발현 정도가 급격히 감소되는 것으로 미루어 보아 이 단계에서 노화가 진행되었음을 추측할 수 있었다. 3)동일한 시간과 농도로 처리했을 때 각각의 passage의 발현 level에서 보이는 양상과는 다르게 35 passage에서는 500${\mu}M$이상의 농도를 1 시간동안 노출시켰을 경우에 Cu/Zn SOD가 거의 발현되지 않았으며, 30 분 동안 노출시켰을 때에는 500 ${\mu}M$의 농도까지 방어할 수 있는 능력을 가진 것으로 보인다.

• Archives of Pharmacal Research
• /
• 제27권2호
• /
• pp.173-176
• /
• 2004

Three phenolic compounds, rosmarinic acid (1), methyl rosmarinate (2), ethyl rosmarinate (3), and two flavonoids, luteolin (4), luteolin-7-O-$\beta$-D-glucuronide methyl ester (5) were isolated from the aerial part of Lycopus lucidus (Labiatae). Their structures were determined by chemical and spectral analysis. Compounds 1-5 exhibited potent antioxidative activity on the NBT superoxide scavenging assay. The $IC_{50}$ values for compounds 1-5 were 2.59, 1.42, 0.78, 2.83, and 3.05 $\mu\textrm{g}$/mL respectively. In addition, five compounds were isolated from this plant for the first time.

• Food Science and Biotechnology
• /
• 제15권6호
• /
• pp.993-996
• /
• 2006

Cyanidin 3-glucoside (C3G) isolated from black rice was investigated for hepatoprotective effects in HepG2 cells under oxidative stress. When an increase in the production of reactive oxygen species (ROS) was induced by gramoxone, cell viability was drastically decreased by 42%. However, in the presence of C3G, no hepatocytic damage was observed in HepG2 cells treated with gramoxone. C3G was found to manifest a stronger scavenging effect (91%) on superoxide anion radical ($O_2\;^{.-}$) than any of the other natural and synthetic antioxidants. Results suggest that C3G from black rice possesses hepatoprotective effects in vitro, which may be, at least in part, due to $O_2\;^{.-}$ scavenging.

• 한국식품영양과학회지
• /
• 제32권3호
• /
• pp.444-449
• /
• 2003

To investigate the long term effect of buchu (Chinese chives) diet on ROS formation in the liver and stin tissue of ICR mice, one of control, 2% or 5% buchu-added diet was fed to ICR mice for 12 months. Superoxide anion (O2ㆍ), hydrogen peroxide($H_2O$$_2$) and hydroxyl radical (ㆍOH) contents were measured in cytosol, microsome, mitochondria of liver and skin of mice, respectively. Behu diet showed a significant decrease of superoxide anion, hydrogen peroxide and hydroxyl radical contents in liver and skin tissues compared to control diet, and this effect is especially higer at 5% than at 2% buchu diet level. ICR mice showed an age-dependent increase in ROS contents, while the group fed buchu diet decreased its ROS contents significantly and ROS contents of liver appeared to be 2 fold higher than skin. The results of the present study suggest that antioxidative components and sulfur-compounds in buchu diet appear to be responsible for the inhibition of ROS formation in ICR mice.

• 생명과학회지
• /
• 제21권5호
• /
• pp.693-699
• /
• 2011

Spermidine은 spermine의 전구체로 역할을 하는 putrescine로부터 합성되는 polycation의 한 형태이다. 최근에 spermidine는 수명연장에 중요한 역할을 하는 하나의 polyamine으로 알려져 있다. Hydroxyl radical, superoxide 및 hydrogen peroxide와 같은 활성산소(ROS)는 노화뿐만 아니라 다양한 병원성 과정에서 관여한다고 보고되고 있다. DPPH radical, $H_2O_2$ 및 hydroxyl radical에 대한 spermidine의 소거활성과 산화적 스트레스와 관련된 DNA oxidation에 대한 보호 효과가 in-vitro에서 평가되었다. Spermidine은 500 ${\mu}M$ 이상에서 DPPH radical와 $H_2O_2$에 대한 소거 효과를 보여주었다. 특히 활성산소종 중에서 spermidine는 hydroxyl radical에 대한 효과가 탁월하였다. 뿐만 아니라, spermidine는 500 ${\mu}M$에서 DNA oxidation에 대해서도 뚜렷한 보호 효과를 나타내었다. 더욱이 사람피부섬유아세포에서 superoxide dismutase와 같은 항산화 관련 단백질의 발현이 대조군과 비교시 spermidine 존재 하에 증가하였다. 이상의 결과로부터 spermidine은 암, 노화 및 염증을 포함하는 활성산소와 관련 있는 질병들을 예방하기 위한 항산화제로 이용될 수 있을 것이다.

• 한국어병학회지
• /
• 제14권1호
• /
• pp.3-10
• /
• 2001

식물성 생약재의 항균력과 활성산소(superoxide anion, $O_2^-$)의 생산에 미치는 in vitro 효과를 조사하여 금후 in vivo 실험에 적용할 때, 어류 체내 자연 저항성 증진을 꾀할 수 있는 식물성 생약재를 발굴하기 위한 기초자료를 얻고자 하였다. 식물성 생약재는 고삼, 귀전우, 구절초, 박하, 방풍, 연교, 약쑥, 지유, 삼백초, 삼지구엽초, 상백피, 소회향, 편축, 팔각 등 14종류로 이들을 열수추출하여 실험에 사용하였다. 항균력 시험에는 어병세균 Listonella anguillarum(Vibrio anguillarum), Vibrio sp., Vibrio alginolyticus, Edwardsiella tarda, Streptococcus sp., Lactcoccus garvieae를 대상으로 disk법을 사용하였으며, 활성산소의 생산능은 넙치 신장 대식세포를 이용한 nitroblue tetrazolium(NBT) 반응으로써 조사하였다. 그 결과,약쑥이 다른 생약재에 비하여 시험에 사용된 어병 세균에 대한 항균활성이 월등히 뛰어났으며, 또한 넙치 대식세포의 활성산소 생산능을 크게 자극하는 효과가 있음을 확인할 수 있었다.

• Food Science and Biotechnology
• /
• 제16권1호
• /
• pp.90-98
• /
• 2007

The antioxidant activities of water ($H_2O$) and ethanol (EtOH) extracts from hamcho (Salicornia herbacea L.) juice and cake prepared by enzymatic treatments were evaluated by in vitro assays against DPPH, superoxide, and hydroxyl radicals. Among the $H_2O$ and EtOH extracts from five different carbohydrases treated, the EtOH extract from viscozyme-treated hamcho cake had higher yield and phenolic content, and exhibited the strongest radical scavenging activity against DPPH ($IC_{50}=186.91\;{\mu}g/mL$), superoxide ($IC_{50}=87.54\;{\mu}g/mL$), and hydroxyl radicals ($IC_{50}=367.07\;{\mu}g/mL$). Antioxidant assay-guided fractionation and purification of the EtOH extract led to isolation and identification of five phenolic compounds, procatechuic, ferulic and caffeic acids, quercetin, and isorhamnetin. Most of these phenolic compounds exhibited considerable DPPH, superoxide, and hydroxyl radical scavenging activities, and in particular, caffeic and ferulic acids had stronger superoxide and hydroxyl radical scavenging activities than the well-known antioxidant radical scavenger, (+)-catechin (p<0.05). Quercetin and isorhamnetin were the primary compounds responsible for the strong antioxidant activity in the EtOH extract of the viscozyme-treated hamcho cake. Meanwhile, these five phenolic compounds were detected in the EtOH extract of the viscozyme-treated hamcho cake at the following levels (dry base of hamcho); procatechuic acid (1.54 mg%), caffeic acid (6.87 mg%), ferulic acid (8.45 mg%), quercetin (12.63 mg%), and isorhamnetin (6.65 mg%). However, three of these phenolic compounds (procatechuic, caffeic acid, and ferulic acids) were detectable in the $H_2O$ extract of viscozyme-treated hamcho juice. These results suggest that the EtOH extract of viscozyme-treated hamcho cake may be a potential source of natural antioxidants.

• Biomolecules & Therapeutics
• /
• 제8권1호
• /
• pp.32-37
• /
• 2000

Recently new soybean saponins with D DMP (2,5-dihydroxy-6-methyl-2,3,- dihydro-4H-pyran-4-one) moiety have been isolated from legumes. The purpose of this study is to characterize ROS scavenging activities of DDMP saponins ($\alpha$g, $\beta$g saponin) isolated from Glycine max (L.) Merrill. The scavenging activity on OH was examined in terms of lipid peroxidation in the rat liver homogenates and the same activity on $O_2$ was also determined in the xanthine-xanthine oxidase system, respectively. Up to 0.25 mg DDMP saponins ($\alpha$g and $\beta$g saponins) did not cause any significant effects on the prevention of lipid peroxidation as compared with the control group. In terms of superoxide scavenging activities, 0.25 and 0.5 mg $\alpha$g saponin inhibits only 2.6% and 5.5% (p<0.05) of the control group, respectively. However, $\alpha$g saponin dose-dependently (p<0.01, r=0.955) inhibits the formation of superoxide radical unto 21.3% of the control group with a maximal dose of 0.5 mg (p<0.01), equivalent to 0.17 units of superoxide dismutase activity.