• Title, Summary, Keyword: antioxidant

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Purification and Characterization of Thiol-Specific Antioxidant Protein from Human Liver: A Mer5-Like Human Isoenzyme

  • Cha, Mee-Kyung;Kim, Il-Han
    • BMB Reports
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    • v.29 no.3
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    • pp.236-240
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    • 1996
  • A 23-kDa molecular mass of antioxidant protein was purified from human liver. This protein exhibited the preventive effect against the inactivation of glutamine synthetase by a metal-catalyzed oxidation system. This antioxidant activity was supported by a thiol-reducing equivalent such as dithiothreitol in a similar manner to that of the 25-kDa thiol-specific antioxidant protein (TSA) from human red blood cells (HR). However, a thioredoxin-linked peroxidase activity of thiol-specific antioxidant protein of human liver (HLTSA) (0.91 ${\mu}mol/min/nmol$ of HLTSA) was much lower than that of thiol-specific antioxidant protein of human red blood cells (HRTSA) (16.4 ${\mu}mol/min/nmol$ of HRTSA). This HLTSA is also immnologically distinct from HRTSA Amino acid sequences of the three tryptic peptides (P1, P2, P3) of HLTSA were found to be completely homologous to segments of the known Mer5-like protein, which belongs to the known TSA family.

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Antioxidant Flavonoids and Chlorogenic Acid from the Leaves of Erobotrya japonica

  • Jung, Hyun-Ah;Park, Jong-Cheol;Chung, Hae-Young;Kim, Jong;Choi, Jae-Sue
    • Archives of Pharmacal Research
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    • v.22 no.2
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    • pp.213-218
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    • 1999
  • The antioxidant activity of Eriobotrya japonica was determined by measuring the radical scavenging effect on DPPH (1,1-diphenyl-2-picrylhydrazyl) radical and lipid peroxidation produced when mouse liver homogenate was exposed to the air at $37^{\circ}C$, using 2-thiobarbituric acid (TBA). The methanol extract and its factions of Eriobotrya japonica leaves showed strong antioxidant activity. The antioxidant activity of EtOAc and n-BuOH soluble fractions were stronger than the others, and were further purified by repeated silica gel, MCl gel CHP-20P, and Sephadex LH-20 column chromatography. Antioxidant chlorogenic acid, quercetin-3-sambubioside from n-BuOH fraction and methyl chlorogenate, kaempferol- and quercetin-3-rhamnosides, together with the inactive ursolic acid and$ 2{\alpha}$-hydroxyursolic acid from EtOAc fraction were isolated. Antioxidant flavonoids and chlorogenic acid also showed prominent inhibitory activity against free radical generation in dichlorofluorescein (DCF) method.

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Comparison of Antioxidant Potentials in Methanolic Extracts from Soybean and Rice Fermented with Monascus sp.

  • Pyo, Young-Hee
    • Food Science and Biotechnology
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    • v.16 no.3
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    • pp.451-456
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    • 2007
  • The potential antioxidant activities of methanolic extracts from soybean and rice fermented with Monascus sp. were investigated. M. pilosus IFO 480 and M. anka IFO 478 were screened as a suitable strain to promote the antioxidant activities in soybean- and rice- fermentation. The methanol extracts from soybean and rice after fermenting for 20 days at $30^{\circ}C$ resulted in a significant increase in the antioxidant capacities expressed as radical (ABTS and DPPH) scavenging assay and peroxidation inhibition (%) by thiocyanate method and increased (p<0.01) by a 2.6 to 3.1-fold compared with those of the unfermented products. The average antioxidant potentials of Monascus-fermented soybean extracts (MFSE) were significantly (p<0.01) stronger than Monascus-fermented rice extracts (MFRE). A linear correlations between free radical scavenging activity of MFSE and the total phenolics content (r=0.84) and total flavonoids content (r=0.81) were observed. These results indicated that MFSE exhibited stronger (p<0.01) antioxidant activity and contained significantly higher levels (p<0.05) of phenolics than MFRE.

Antioxidant and free radical scavenging activities of Cleome rutidosperma

  • Bose, Anindya;Mondal, Sumanta;Gupta, Jayanta Kumar;Ghosh, Tirtha;Debbhuti, Debabrata;Si, Sudam
    • Oriental Pharmacy and Experimental Medicine
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    • v.8 no.2
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    • pp.135-145
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    • 2008
  • The study was aimed at evaluating the antioxidant and free radical scavenging activities of ethanolic extract and its fractions of Cleome rutidosperma. The antioxidant activity, reducing power, total phenolic content, total flavonoid content, superoxide anion scavenging activity, nitric oxide anion scavenging activity, in vitro antilipid peroxidation activity and in vitro non-enzymatic hemoglobin glycosylation were studied. The results obtained in the study indicate that Cleome rutidosperma is a potential source of natural antioxidant. All the parameters were found to be concentration dependent and increased with increasing amounts of sample. Flavonoids, phenolic compound like tannins, terpenoids may be responsible for the antioxidant activity of the plant. Variation of solubility parameters in various models may be attributed to non-linearity of activity of ethanol extract fractions models. Further investigation on the isolation and identification of antioxidant component(s) in the plant may lead to chemical entities with potential for clinical use.

Antioxidant Activities and Total Phenolics of Ethanol Extracts from Several Edible Mushrooms Produced in Korea

  • Choi, Young-Min;Ku, Ja-Bi;Chang, Hoo-Bong;Lee, Jun-Soo
    • Food Science and Biotechnology
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    • v.14 no.5
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    • pp.700-703
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    • 2005
  • Eight edible mushrooms grown in Korea were extracted with ethanol at room temperature for 24 hr. The extracts were investigated for their antioxidant activities as measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical cation scavenging activities. Among the mushroom extracts evaluated in this study, the ethanolic extracts from Ganoderma lucidum and Pleurotus eryngii showed the greatest potential antioxidant activity, by producing 85 and 88% inhibition in DPPH radical scavenging method and 219 and 165 mg ascorbic acid equivalent antioxidant capacity (AEAC), respectively. Total phenolics and total flavonoids in the ethanolic extracts were determined by spectrophotometric method. Positive correlations were found between total phenolic contents in the extracts and their antioxidant activities, suggesting that phenolic contents in the mushrooms extracts are mainly responsible for their antioxidant activities.

Antioxidant Activity of Main and Fine Roots of Ginseng (Panax Ginseng C.A. Meyer) Extracted with Various Solvents

  • Kim, Ji-Sang;Yoon, Ki-Sun;Lee, Young-Soon
    • Food Science and Biotechnology
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    • v.17 no.1
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    • pp.46-51
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    • 2008
  • The objective of this study was to investigate antioxidant activities of freeze-dried, main root, and fine root of ginseng (Panax ginseng CA. Meyer), which were extracted with various solvents including ethanol, methanol, and water. Ethanol extracts in both parts showed the most powerful scavenging activities against DPPH radicals. Especially, ethanol extract of fine root had higher reducing power and antioxidant capacity than that of main root. The highest antioxidant activity in linoleic acid emulsion system was also observed in fine root extracted with ethanol, followed by methanol and water. Both ferrous ion chelating activity and ferric reducing antioxidant power (FRAP) of extracts were increased with the increase of extracts concentration. These results suggest that ethanol extract of fine root of ginseng has the most effective antioxidant capacity compared to the methanol and water extracts tested in the present study. Thus it can be applied for the effective extraction of functional material from ginseng for the usage of pharmaceutical and/or food industries.

Antioxidant activities and nutritional characteristics of smoked duck marinated in natural curing agent (천연 염지제를 첨가한 오리훈제의 항산화 활성과 영양적 특성)

  • Bark, Yeon Ok
    • Journal of Nutrition and Health
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    • v.47 no.6
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    • pp.484-488
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    • 2014
  • Purpose: This study investigated the question of whether the addition of natural ingredients (pear fermented solution, celery powder, vitamin C) in curing agents may influence antioxidant activities and nutritional characteristics of smoked duck. Methods: Smoked duck samples with general or natural curing agent containing three additive ingredients were examined to determine total polyphenol contents, antioxidant activities, pH, TBARS, and food additives residue (nitrite ion, antioxidant, sodium glutamate). Results: Smoked duck with natural curing agent showed a higher level of total polyphenol content and antioxidant activities than smoked duck using general curing agent (p < 0.05). The pH and TBARS of smoked duck were significantly decreased by the addition of natural curing ingredients compared to those of smoked duck using general curing agent (p < 0.05). The residues of food additives were not detected in smoked duck using natural curing agent. Conclusion: Findings suggest that the addition of pear fermented solution, celery powder, and vitamin C in natural duck curing agent may improve the antioxidant activities and nutritional characteristics of smoked duck and provides health benefits.

Antioxidant, Anti-inflammatory and Cytotoxicity on Human Lung Epithelial A549 Cells of Jerusalem artichoke (Helianthus tuberosus L.) Tuber

  • Zhang, Qin;Kim, Hye-Young
    • Korean Journal of Plant Resources
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    • v.28 no.3
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    • pp.305-311
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    • 2015
  • This study investigated in vitro antioxidant, anti-inflammatory and cytotoxicity on human lung epithelial A549 cells of different solvent extracts from Jerusalem artichoke (Helianthus tuberosus L.) tuber. The EtOH extract contained amounts of phenolics (22.20 tannic acid equivalent ㎎/ɡ) and exhibited the highest antioxidant activity and anti-inflammatory activity. Several methods were employed for measure the antioxidant activity: 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity (IC50 = 206.79 ㎍/㎖), reducing power activity (21.26 ascorbic acid equivalent ㎎/ɡ) and total antioxidant activity (19.05 ascorbic acid equivalent ㎎/ɡ). Meantime, the EtOH extract inhibited the NO production completely with a concentration of 800 ㎍/㎖. Besides, the H2O extract exhibited more potent effect on human lung epithelial A549 cells. This study suggested that Jerusalem artichoke tuber had antioxidant, anti-inflammatory and cytotoxicity on human lung epithelial A549 cells.

Antioxidant Activity and Protective Effects of Extracts from Sambucus williamsii var. coreana on t-BHP Induced Oxidative Stress in Chang cells (접골목 추출물에 의한 항산화 활성이 정상 간세포의 t-BHP 유발 산화스트레스에 미치는 영향)

  • Kim, Kitae
    • The Journal of the Korean Medicine Diagnostics
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    • v.17 no.3
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    • pp.275-286
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    • 2013
  • In the present study, antioxidant activity and protective effect of extracts from Sambucus williamsii var. coreana stems (SWC) were evaluated on tert-butyl hydroperoxide (t-BHP) induced oxidative stress in human liver (Chang) cells. Antioxidant activities of the SWC extracts were determined by various radical scavenging activities, such as DPPH, ferric reducing antioxidant power (FRAP), 2,2'-azinobis-(3-ethybenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity and oxygen radical absorbance capacity (ORAC) assay. SWC extracts showed strong antioxidant effect on various assay. To determine the hepatoprotective effects of SWC on t-BHP induced oxidative damage, cell viability was measured using MTT assay. Pretreatment of SWC extracts showed increasing cell viability, decreasing ROS and restoring mitochondria membrane potential on t-BHP induced oxidative stress in Chang cells. Our findings suggest that SWC extracts may be considered a potential agent for therapeutic protective effect from oxidative stress through its antioxidant activity.

Oxidative stress and the antioxidant enzyme system in the developing brain

  • Shim, So-Yeon;Kim, Han-Suk
    • Clinical and Experimental Pediatrics
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    • v.56 no.3
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    • pp.107-111
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    • 2013
  • Preterm infants are vulnerable to the oxidative stress due to the production of large amounts of free radicals, antioxidant system insufficiency, and immature oligodendroglial cells. Reactive oxygen species (ROS) play a pivotal role in the development of periventricular leukomalacia. The three most common ROS are superoxide ($O2^{\cdot-}$), hydroxyl radical ($OH^{\cdot}$), and hydrogen peroxide ($H_2O_2$). Under normal physiological conditions, a balance is maintained between the production of ROS and the capacity of the antioxidant enzyme system. However, if this balance breaks down, ROS can exert toxic effects. Superoxide dismutase, glutathione peroxidase, and catalase are considered the classical antioxidant enzymes. A recently discovered antioxidant enzyme family, peroxiredoxin (Prdx), is also an important scavenger of free radicals. Prdx1 expression is induced at birth, whereas Prdx2 is constitutively expressed, and Prdx6 expression is consistent with the classical antioxidant enzymes. Several antioxidant substances have been studied as potential therapeutic agents; however, further preclinical and clinical studies are required before allowing clinical application.