• 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 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.

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 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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Antioxidant and free radical scavenging activities of Cleome rutidosperma

  • Bose, Anindya;Mondal, Sumanta;Gupta, Jayanta Kumar;Ghosh, Tirtha;Debbhuti, Debabrata;Si, Sudam
    • Advances in Traditional 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.

Optimization of the Extraction Parameters of Gardenia (Gardenia jasminoides Ellis) Fruits for the Maximum Antioxidant Capacity

  • Yang, Bin;Liu, Xuan;Teng, Dike;Gao, Yanxiang
    • Food Science and Biotechnology
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    • v.18 no.4
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    • pp.867-871
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    • 2009
  • Response surface methodology (RSM) was used for the optimization of antioxidant capacity in gardenia extracts. The antioxidant capacities of gardenia fruit extracts were investigated by ferric reducing ability (FRA) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity (RSA) assays. The optimum extraction parameters for the strongest antioxidant capacity were the ethanol concentration (EtOH) of 48.9%, extraction temperature of $72.9^{\circ}C$, and extraction time of 29.9 min. Analysis of variance (ANOVA) showed that the quadratics of EtOH and extraction temperature had highly significant effect on the antioxidant capacity (p<0.001). The antioxidant capacity was correlated with contents of bioactive components [crocin, geniposide, and total phenolic (TP) compounds] in gardenia extracts and mainly attributed to the content of the TP compounds.

Melt-Grafting of Maleimides Having Hindered Phenol Group onto Polypropylene

  • Kim, Taek-Hyeon;Lee, Nam-Gun
    • Bulletin of the Korean Chemical Society
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    • v.24 no.12
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    • pp.1809-1813
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    • 2003
  • Monomeric antioxidant 1 was prepared by the reaction of 3,5-di-tert-butyl-4-hydroxybenzyl alcohol with N-[4-(chlorocarbonyl)phenyl]maleimide in the presence of imidazole. Monomeric antioxidant 2, bearing carbamate group, was synthesized from the reaction of 3,5-di-tert-butyl-4-hydroxybenzyl alcohol and azidomaleimide. Antioxidant 3 was prepared by the reaction of N-(4-hydroxyphenyl)maleimide and 3-(3,5-ditert-butyl-4-hydroxyphenyl) propionic chloride in the presence of triethylamine. These reactive antioxidants were grafted onto polypropylene (PP) by melt-processing with free radical initiators in a mini-max moulder. From the infrared spectra of the grafted PP, it was found that the monomeric antioxidants were grafted onto PP. IR spectroscopic methods were used for the quantitative determination of the extent of grafting of monomeric antioxidant. To optimize the reaction conditions, the influences of the concentration of DCP, monomeric antioxidant, reaction time and temperature on the extent of grafting were studied.

Assessment of Allelopathic Potential and Antioxidant Activity of Leaf Extracts from Three Compositae Plants

  • Chon, Sang-Uk;Park, Seong-Kyu
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.48 no.4
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    • pp.303-307
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    • 2003
  • Some Compositae plants are known to contain biologically active substances that are allelopathic to weeds species as well as antioxidant to foods. Aqueous extracts from leaves of 3 plant species, Cirsium japonica, Kalimeris yomena, and Lactuca saliva, were bioassayed against alfalfa (Medicago saliva) to determine their allelopathic effects. The extracts applied on filter paper in bioassay significantly inhibited root growth of alfalfa. Extracts of 20 g dry tissue $\textrm{L}^{-1}$ from Lactuca sativa showed the most inhibitory effect on alfalfa seedling growth and followed by Cirsium japonica and Kalimeris yomena. Oxidative stability by Rancimat method and antioxidant activity by TBA method for the ground samples were the greatest in Lactuca sativa although were less than that of a commonly used antioxidant, 1% ascorbic acid. Antioxidant activity of methanol extracts on storing meat was stably kept for 28days and was excellent compared to control. These results suggest that three Compositae plants have potent allelopathic and antioxidant effects, and that their activities differ, depending on plant species.

Antioxidant mechanism of black garlic extract involving nuclear factor erythroid 2-like factor 2 pathway

  • Ha, Ae Wha;Kim, Woo Kyoung
    • Nutrition Research and Practice
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    • v.11 no.3
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    • pp.206-213
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    • 2017
  • BACKGROUN/OBJECTIVES: Although studies have revealed that black garlic is a potent antioxidant, its antioxidant mechanism remains unclear. The objective of this study was to determine black garlic's antioxidant activities and possible antioxidant mechanisms related to nuclear factor erythroid 2-like factor 2 (Nrf2)-Keap1 complex. METHODS/MATERIALS: After four weeks of feeding rats with a normal fat diet (NF), a high-fat diet (HF), a high-fat diet with 0.5% black garlic extract (HF+BGE 0.5), a high-fat diet with 1.0% black garlic extract (HF+BGE 1.0), or a high-fat diet with 1.5% black garlic extract (HF+BGE 1.5), plasma concentrations of glucose, insulin,homeostatic model assessment of insulin resistance (HOMA-IR) were determined. As oxidative stress indices, plasma concentrations of thiobarbituric acid reactive substances (TBARS) and 8-isoprostaglandin $F2{\alpha}$ (8-iso-PGF) were determined. To measure antioxidant capacities, plasma total antioxidant capacity (TAC) and activities of antioxidant enzymes in plasma and liver were determined. The mRNA expression levels of antioxidant related proteins such as Nrf2, NAD(P)H: quinone-oxidoreductase-1 (NQO1), heme oxygenase-1 (HO-1), glutathione reductase (GR), and glutathione S-transferase alpha 2 (GSTA2) were examined. RESULTS: Plasma glucose level, plasma insulin level, and HOMA-IR in black garlic supplemented groups were significantly (P < 0.05) lower than those in the HF group without dose-dependent effect. Plasma TBARS concentration and TAC in the HF+BGE 1.5 group were significantly decreased compared to those of the HF group. The activities of catalase and glutathione peroxidase were significantly (P < 0.05) increased in the HF+BGE 1.0 and HF+BGE 1.5 groups compared to those of the HF group. The mRNA expression levels of hepatic Nrf2, NQO1, HO-1, and GSTA2 were significantly (P < 0.05) increased in the HF with BGE groups compared to those in the HF group. CONCLUSIONS: The improvements of blood glucose homeostasis and antioxidant systems in rats fed with black garlic extract were related to mRNA expression levels of Nrf2 related genes.

Antioxidant potential of a soft cheese (paneer) supplemented with the extracts of date (Phoenix dactylifera L.) cultivars and its whey

  • Qureshi, Tahir Mahmood;Amjad, Aniqa;Nadeem, Muhammad;Murtaza, Mian Anjum;Munir, Masooma
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.10
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    • pp.1591-1602
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    • 2019
  • Objective: The present study was conducted to evaluate the antioxidant potential of paneer, a soft cheese supplemented with various water soluble date extracts during storage. Further, the whey obtained from all the paneer samples was also investigated for its antioxidant potential. Methods: The date cultivars were evaluated for their physico-chemical characteristics and date extracts were assessed for their antioxidant potential. Physico-chemical evaluation, microbiological quality and further antioxidant potential of the prepared paneer were carried out during storage period (0 to 8 days, $5^{\circ}C$). Results: All the date extracts were found to have considerable antioxidant activity due to presence of total phenolics and flavonoids. Owing to the presence of phenolics and flavoinds in date extracts, supplemented paneer showed higher trolox equivalent antioxidant capacity, reducing power and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity than control paneer. Paneer supplemented with Rabi extracts had the highest total phenolics ($190.7{\mu}g$ gallic acid equivalent/g paneer), DPPH radical scavenging activity ($928.1{\mu}mol$ equivalent of Trolx/g paneer) and trolox equivalent antioxidant capacity ($9.2{\mu}mol$ equivalent of Trolx/g paneer). The whey obtained from control paneer showed lower values of total phenolics, total flavonoids, DPPH, trolox equivalent antioxidant capacity and reducing power as compared to the values of whey obtained from paneer supplemented with date extracts. Conclusion: Paneer supplemented with date extracts and its whey may offer potent antioxidant activity.