• Journal of the Korean Chemical Society
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• v.36 no.6
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• pp.894-905
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• 1992

Dioxygen binding and homogeneous catalytic oxidation of hydrazobenzene were investigated by employing tetradentate Schiff base Cobalt(II) complexes such as Co(II)(SED)$(Py)_2$, Co(II)(SOPD)$(Py)_2$ and Co(II)(SND)$(Py)_2$ in saturated oxygen methanol solvent. The major product of hydrazobenzene ($H_2$AB) oxidation by catalysts of superoxo type [Co(III)(SED)(Py)$O_2$] and [Co(III)(SOPD)(Py)$O_2$] complexes are trans-azobenzene (t-AB) and rate constants k for oxidation reaction was 7.692 ${\times}$ $10^{-2}$ M/sec for [Co(III)(SED)(Py)$O_2$] and 5.076 ${\times}$ $10^{-2}$ M/sec for [Co(III)(SOPD)(Py)$O_2$]. But cis-azobenzene (c-AB) are obtained as a major product with ${\mu}$-peroxo type [Co(III)(SED)(Py)]$_2O_2$ catalyst, and rate constant k is 1.266 ${\times}$ $10^{-2}$ M/sec. The rate constants of oxidation reaction has been studied spectrophotometrically and the rate law established. A mechanism involving a intermediate activated complexes of catalyst, hydrazobenzene and oxygen has been proposed. $H_2$AB + Co(II)(Schiff base)$(Py)_2$ + $O_2$ ${\rightleftharpoons}_{MeOH}^K$ Co(III)(Schiff base)(Py)$O_2$${\cdot}$$H_2$AB + Py $\longrightarrow^k$ Co(II)(Schiff base)$(Py)_2$ + t-AB + $H_2O_2$(Scchiff base : SED and SOPD). $H_2$AB + 2Co(II)(SND)$(Py)_2$ + $O_2$ ${\rightleftharpoons}_{MeOH}^K$ [Co(III)(SND)(Py)]$_2O_2$${\cdot}$H_2$AB + 2Py ${\longrightarrow}^k$ (Co(II)(SND)$(Py)_2$ + c-AB + $H_2O_2$.

• Food Science and Preservation
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• v.24 no.8
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• pp.1067-1078
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• 2017

This study was carried out to investigate the physicochemical and antioxidant properties of fermented milk with addition of hot water extract of Cordyceps militaris grown upon Tenebrio molitor. The general components of Cordyceps militaris grown upon Tenebrio molitor are moisture 10.85%, crude protein 18.44%, crude fat 2.07%, crude ash 5.46%. The DPPH radical scavenging activities of different solvents were the highest (74.81 EDA%) with hot water extract sample. The acidity of fermented milk was high with increasing amount of extracts. The pH of fermented milk reached 4.60-4.66 after 4 h of fermentation, and the number of lactic acid bacteria was highest (11.70 log CFU/mL) with 1% fermented milk. The moisture content of fermented milk showed no significant difference. In addition, contents of crude protein were not significantly different according to addition amount. Regarding Hunter's color values, L value decreased as the amount of extract increased, whereas a value and b value increased. The content of free amino acid increased with increasing amount of extract. The DPPH free radical scavenging ability and ABTS free radical scavenging ability of fermented milk were significantly different as the addition amount of extract increased. In the sensory evaluation, fermented milk containing 1% of extract showed the highest preference.

• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1248-1254
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• 1997

To measure antioxidative activities, the various extracts from RVS (Rhus Verniciflua Stokes) were tried out with either DPPH or thiocyanate method. Also we used the GO (Glucose Oxidase) 20 mU/mL hydroxyl radical system in mouse whole brain cell culture. Chloroform, n-hexane or ethanol were used as extract solutions which had different polarity respectively. In DPPH and thiocyanate method, the antioxidative activities of the crude ethanol extracts were stronger than other extracts. The crude ethanol extracts were fractionated 5 peaks by glass column. Among of them, antioxidative activity of peak II $(P_{II})$ was shown stronger than other fractions, a little for peak III $(P_{III})$ and peak IV $(P_{IV})$, and none for peak I $(P_I)$ and Peak V $(P_V)$. In the antioxidative effects of crude ethanol extracts (30 mg/mL), cell viabilities were evaluated $1\;{\mu}L\;(297\;{\mu}g/mL)$, $2\;{\mu}L\;(588\;{\mu}g/mL)$ of crude ethanol extracts 59%, 68% respectively. $10\;{\mu}L\;(2,727\;{\mu}g/mL)$ addition of crude ethanol extracts had 95% cell viabilities, 0.01% significant, comparing control. In addition, the compounds related to antioxidative effect of crude ethanol extract might be glycoproteins by means of SDS-PAGE. Comparison to antioxidative effects between several antioxidants (ascorbic acid, ${\alpha}-tocopherol$, catalase) $273\;{\mu}L/mL$ addition of crude ethanol extracts corresponds to $1\;{\mu}g/mL$ catalase in antioxidative effects.

• Korean Journal of Medicinal Crop Science
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• v.11 no.1
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• pp.53-61
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• 2003

Cirsium japonicum var. ussuriense were extracted with methanol and then fractionated with nhexane, EtOAc and BuOH to get active fractions. And their antioxidant and antimicrobial activities in each fraction were determined. Ethyl acetate and butanol fraction of Cirsium japonicum var. ussuriense showed strong antioxidant activities, but hexane fraction did not show any activities. But in the antimicrobial test, Ethyl acetate fraction showed strong antimicrobial activities except to Aspergillus awamori, Asperigillus niger. Especially, Ethyl acetate fraction showed the strongest activities against Bacillus subtilis. And aqueous fraction showed the strongest activities against Cladosporium herbarum, Hypocrea nigricans. This study was performed to determine the antimutagenic and cytotoxic effect of Cirsium japonicum var. ussuriense methanol extract on Salmonella typhimurium TA98, TA100 and cancer cell lines using Ames test and cytotoxicity assay, respectively. Cancer cell lines include human lung carcinoma(A549), human breast adenocarcinoma(MCF-7) and human hepatocellular carcinoma (Hep3B). Futher fractionations with hexane, ethyl acetate, butanol and water from methanol extract of Cirsium japonicum var. ussuriense were performed to obtain effective fraction, methanol extract showed 60.14% inhibition effect on the mutagenesis induced by MNNG against TA100, while 77% and 72.5% inhibition was observed on the mutagenesis induced by 4NQO against TA98 and TA100, respectively. and methanol extract showed 82.25% and 73.7% inhibitory effect on the mutagenesis induced by Trp-P-1 against TA98 and TA100, respectively. methanol extract showed the strongest effect against A549, MCF-7 and Hep3B at the same concentration compared to those of other fration.