• Food Science and Biotechnology
• /
• v.14 no.6
• /
• pp.715-721
• /
• 2005

Antioxidant activities of grape seeds extracted with various solvents were evaluated by measuring total phenol and flavanol contents, thiobarbituric acid reactive substances (TBARS) following lipid peroxidation, 2-deoxyribose degradation, SOD-like activity, 2,2'-azino-bis(3-ethylbenzthizaoline-6-sulfonic acid (ABTS) radical-scavenging ability, and electron-donating ability using 1,1-diphenyl-2-pycryl hydrazil (DPPH) method. Total phenol and flavanol contents of mixted-solvent extracts were higher than those of single-solvent extracts, with the mixing ratio of 17:3 (ethyl acetate: water) (EW) showed the highest contents. Antioxidant activities (%) of TBARS following phosphatidylcholine peroxidation were 14, 45, 45, 7, 4, 25, 21, 23, and 20% for ascorbic acid (AA), butylated hyroxytoluene (BHT), quercetin (Q), acetone extract (AT), ethyl acetate (EA) extract, methanol (MeOH) extract, 4:1 (EA) extract, 9:1 (EW)-extract, and 17:3 EW extract, respectively. Antioxidant activities for 2-deoxyribose degradation were 5, 80, 87, 78, 56, 73, 64, 60, and 75% in AA, BHT, Q, AT, EA, MeOH extract, 4:1 EW extract, 9:1 EW extract, and 17:3 EW extract, respectively. MeOH grape seed extract showed distinctly stronger electron-donating activity than other solvent extracts.

• Archives of Pharmacal Research
• /
• v.19 no.2
• /
• pp.112-115
• /
• 1996

Some antioxidant phenolic compounds exhibit prooxidant activity mainly due to their abilities to reduce $Fe^{3+}\; to\; Fe^{2+}.$ Reducing ability and prooxidant activity of maltol, an antioxidant component of Korean red ginseng, were compared with those of pyrogallol. Maltol at 2 mM did not appreciably reduce$ Fe^{3+}\; to\; Fe^{2+}$ and also failed to reduce nitroblue tetrazolium. Stimulation of hydroxyl radical mediated-deoxyribose degradation by pyrogallol was maximal at 60 .mu.M. Maltol stimulated the deoxyribose degradation to a much less extent, and a similar stimulatory effect was observed at a concentration of more than 100-fold higher than that of pyrogallol. The stimulatory effect of maltol reached a plateau over 1 mM, suggesting the removal of hydroxyl radicals by excess maltol. In bleomycin-$Fe^{3+}$-DNA assay, maltol at 2 mM produced a 2.5-fold increase of the iron-bleomycin-dependent DNA degradation over the basal value, whereas pyrogallol at 10 .mu.M accelerated DNA degradation by ca. 10-fold. Furthermore, maltol inhibited $Fe^{2+}$-stimulated DNA degradation by bleomycin. These results strongly suggested that maltol is an antioxidant with little prooxidant activity.

• Korean Journal of Acupuncture
• /
• v.22 no.4
• /
• pp.57-65
• /
• 2005

Objectives : Circium japonicum is a pharmacologically active used in traditional Korean medicine. An aqua-acupuncture solution of the Circium japonicum was assessed to determine the mechanism of its antioxidant activity. Materials : Circium japonicum was obtained from a Dongguk Korean Medicine Hospital (Kyung-ju, Kyungbuk). The freeze-dry powder was collected (yield 5.1%) for the aqua-acupuncture solution. Scavenging activity on DPPH free radicals by the Circium japonicum aqua-acupuncture solution (CJAS) was assessed according to the method followed by Gyamfi et al.. and then scavenging activity orl superoxide radicals $(O_2^-{\cdot})$ was assessed by the method described by Gotoh et al. with slight modification. Deoxyribose assay to determine the rate constant for the reactions between either antioxidants and hydroxyl radicals or antioxidants and iron ions. We tested by; (1) Non-site-specific scavenging assay (hydroxyl radicals, OH), (2) Site-specific scavenging assay (chelate iron ions), and (3) Pro-oxidant effect of the CJAS on iron dependent hydroxyl radical generation. Finally, we determined hydroxyl radical-mediated DNA nicking formation. Conclusion : Our study demonstrated that CJAS has antioxidant activities and we investigated the potential effectiveness of CJAS in preventing oxidative stress-mediated disease further.

• KSBB Journal
• /
• v.18 no.4
• /
• pp.282-288
• /
• 2003

For the screening of anti-inflammation and antioxidative activities, ethanolic extract of 40 species of traditional herbal medicines were examined their hyaluronidase inhibitory effect and radical scavenging activity in vitro. From the result of the hyaluronidase inhibitory activity using a Morgan-Elson assay, Astragali Radix, Eucommia Cortex, Schizandrae Fructus, Scutellaria Radix, Acanthopanacis Cortex, Chaenomelis Fructus, Amomum xanthioides Wallich and Moutan Radicis Cortex showed more than 50% hyaluronidase inhibitory effects at the concentration of 10 mg/mL. In the various solvent fractions (n-hexane, chloroform, ethyl acetate, water) prepared from ethanolic extracts, the ethyl acetate fraction of all extracts tested showed strong activity. Antioxidative activity was evaluated by assaying electron-donating ability to DPPH free radical and scavenging of hydroxyl radical (ㆍOH) generated through Fenton reaction, respectively. Rubus coreanus Miq, Moutan Radicis Cortex, Paeoniae Radix Alba, Plantaginis Semen and Sorbus commixta Hedl. showed high activity more than 90%, yet similar activity to $\alpha$-tocopherol and BHA at the concentration of 1 mg/mL in electron donating activity. The scavenging effects of ethanolic extracts on hydroxyl radical were investigated using a 2-deoxyribose oxidation method and tested all extracts showed significant radical scavenging activity. The experiment was also performed to examine whether herbal medicines having significant lipid peroxidation inhibitory activity, Schizandrae-Fructus is the strongest inhibitory activity in both linoleic acid and liposome peroxidation.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.35 no.8
• /
• pp.1097-1101
• /
• 2006

In this study, seven species of seaweeds (Sargassum horneri, Grateloupia filicina, Kjellmaniella crassifolia, Porphyra tenera, Ecklonia stolonifera, Scytosiphon lomentaria, Agarum cribrosum) from Gangwon coast were collected for antioxidative assays. The methanol soluble and insoluble (water soluble) fraction which were prepared from 75% methanol extraction were assayed by DPPH method and deoxyribose assay. The antioxidative activity of methanol soluble fraction of Agarum, Scytosiphon and Sargassum reached to 26.60%, 24.28% and 23.40%, respectively. The antioxidative activities of methanol insoluble fractions of the Kjellmaniella and Porphyra were assayed to 29.70% and 21.01% which were higher than methanol soluble fractions with the values of 9.26% and 8.66%, respectively. The results from DPPH assay and deoxyribose assay showed the methanol soluble fractions of Agarum and Sargassum have strong antioxidative activity. However the methanol insoluble (water soluble) fractions of seaweeds did not show any meaningful antioxidant activity excepted Kjellmaniella and Porphyra.

• Applied Biological Chemistry
• /
• v.45 no.3
• /
• pp.162-167
• /
• 2002

Free, soluble esterified and insoluble bounded phenolic acids were separated from Eungi chestnut endoderm. The composition and contents of phenolic acid were analyzed by gas chromatography, and their antioxidant activity was examined by DPPH assay, 2-deoxyribose oxidation, and ferric thiocyanate method. Gallic, ellagic, salicylic, and gentisic acids in free phenolic acid fraction, gallic, ellagic, and protocatechuic acids in soluble esterified fraction, sianpic and gentisic acids were the major phenolic acids in insoluble bounded fraction. Marked differences were observed in the phenolic acid composition and contents among the fractions. Free phenolic acid fraction showed the strongest antioxidant activity. Results revealed chestnut endoderm could be a potential antioxidant source containing gallic and ellagic acids.

• Microbiology and Biotechnology Letters
• /
• v.35 no.2
• /
• pp.142-149
• /
• 2007

In this study, we investigated the biological activity of antioxidant and antibacterial activity of citrus by-product ferment. Hot water extracts and 80% methanol extracts from citrus byproduct of ferment were screened for antibacterial activity pathogenic bacteria by paper disc method. Among the various hot water extracts and 80% methanol extracts the Bacillus subtilis showed relatively strong antibacterial activities in the order. The reducing activity on the 1,1-diphenyl-2-picrylhydrazyl(DPPH) radical and ${\cdot}OH$ radical scavenging potential were sequentially screened, in search for antioxidant activities of citrus by-product ferment.