• Korean Journal of Plant Resources
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• v.23 no.1
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• pp.47-53
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• 2010

Flowers and shoots of three species of Dendranthema boreale, Dendranthema indicum, Dendranthema zawdskii var. lucidum, were extracted with 80% ethanol by reflux, and polyphenol content, scavenging activity on DPPH and ABTS radicals, ferrous ion chelating effects and inhibition effects on lipid peroxidation were analyzed. Total polyphenol and flavonoid contents were highest in D. zawdskii var. lucidum, especially in the flower part. Scavenging activity on DPPH and ABTS was also highest in D. zawdskii var. lucidum flower with less activity in shoot. Ferrous ion chelating effects was highest with D. boreale flower and lowest in D. zawdskii var. lucidum flower. Inhibition activity on lipid peroxidation was highest in D. zawdskii var. lucidum shoot with 41.01% inhibition activity showing 32 days after reaction, which is higher than synthetic antioxidant BHT. Due to higher antioxidant level and activity of shoot and flower of D. zawdskii var. lucidum is promising material for natural plant antioxidant. It was also shown that antioxidant activity is different according to plant part ever in same plant, and proper plant species should be used for antioxidant after careful studies.

• Journal of the Korean Applied Science and Technology
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• v.32 no.2
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• pp.302-311
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• 2015

To better investigate the antioxidative property of thermal treatment yam (Dioscorea batatas DECNE.) in Korea, some established methods were used. 70% Methanol, 70% ethanol and chloroform-methanol (CM, 2:1, v/v) extracts were collected. 70% Methanol extract exhibited stronger antioxidative activity evaluated by ferrous ion chelating activity, NO radical scavenging activity and ${\beta}$-carotene bleaching assays. On the contrary, CM extract was the most effective in inhibiting linoleic acid peroxidation. Yam available in Korea was also analyzed for its bioactive compounds such as lycopene, chlorophyll a, b, tannin, phytic acid and total saponin contents. Total saponin was abundant in thermal treatment, which determined to be $42.52{\pm}1.88mg/g$. Based on the results obtained from this study, thermal treatment yam could be used as natural antioxidant source due to its high antioxidant activity and bioactive compound contents.

• Journal of the Korean Chemical Society
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• v.33 no.1
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• pp.113-119
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• 1989

Chelating resins containing hydrazide or triethylenetetramine side chain were prepared using a commercial cation exchage resin, Diaion WK 11, and their nitrogen contents were determined by elemental analysis. The synthesized resin, and commercial chelating resins, (Diaion-CR 10 and-CR 20) were treated with various metal chelates of which metal contents were subsequently determined by chelatometry. Sectioned beads of the resin-metal chelates were also observed using electron microprobs X-ray analyzer. To examine the catalytic activity of the resin-metal chelates, they were applied to the oxidation of various hydroxy compounds and l-ascorbic acid, and found to be effective catalysts.

• Nuclear Engineering and Technology
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• v.15 no.2
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• pp.117-122
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• 1983

The chelating agent with $\beta$-diketo funtional group, 1-phenyl-3-methyl-4-acyl-pyrazolone-5-one, has been used in separating and extracting radionuclides in a waste solution. The derivatives of this pyrazolone compound, prepared by different acyl groups, were synthesized and examined to figure out the extracting ability for Uranium (VI) and Zirconium (IV). The product prepared with succinic anhydride, called succinyl pyrazolone, showed excellent extraction for uranium (VI) in a chloroform solvent system. This result indicates that acyl pyrazolones having carboxylic acid group as a functional group forming $\beta$-diketo functionality are very selective for uranium (VI) and generally other metal ions with high valency.

• Journal of Environmental Science International
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• v.28 no.4
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• pp.393-401
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• 2019

The present study were conducted to determine physiological activities and antioxidant effects [2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity, reducing power, Ferric Reducing Antioxidant Power (FRAP) and Fe2+ (ferrous ion) chelating capacity] of 70% methanol, chloroform:methanol, 2:1 volume ratio (CM) and ethyl acetate extract of turmeric (Curcuma longa L.). Bioactive compound of tannin $0.125{\pm}0.007mg$ Catechin Equivalent (CE)/g dry weight. Turmeric extracts yield were 70% methanol 16.54%, CM 5.64% and ethyl acetate 4.14%, respectively. Antioxidant activity of the samples exhibited a dose-dependent increase. Results showed that extraction solvent had significant effects on total flavonoid content and antioxidant effects of ethyl acetate. But ferrous ion-chelating capacity of 70% methanol extract was higher than CM and ethyl acetate extract. From the results of this study, turmeric can be utilized as a valuable and potential nutraceutical for the functional food industry.

• Journal of environmental and Sanitary engineering
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• v.10 no.2
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• pp.1-12
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• 1995

Under accelerated industrial developments environment pollution comes out to be very stirious. Especially the ions of heavy metal from wastewater, even if they are minimal, accumulated in ecology circle and do finally injury to human health. The general process for removal of heavy metals include coagulation and following sedimentation, ion -exchange and active carbon adsorption and sedimentation that applicate in popular, needs the expense of coagulant the additional treatment of sludge on the general process of coagulation and sedimentation. It is also a serious problem that the second pollution caused by coagulant. However chelating adsorption that uses natural chelating high- molecular compound has not pollution problem Among chelating high- molecules, the diminishing chitin that contained in crustaceans as crawfish and crab in our country with affluent water resources are easy to get. So it is advantageous to use this ubiquitous material for removing heavy metals because we could reuse natural resource. In this research, the author tested the effectiveness of the adsorption and removal of heavy metal ions by chitin and its derivatives. Chitin and cellulose became beads and used as flocculant, in this test. The results are as follows . First, bead showed higher removal ratio than powder in the comparative test on adsorbents such as chitin, chitosan and cellulose. Secondly, in the variety test by the kinds of adsorbent and time. chitosan bead and cellulose bead that showed the highest removal ratio. One hour need to remove the ions of heavy metal. Thirdly, the results of the adsorption degree test by pH revealed high removal ratio adsorption of chitin, cellulose and chitosan bead in alkalin condition but chitosan bead in acidic condition.

• Journal of Soil and Groundwater Environment
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• v.12 no.5
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• pp.105-114
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• 2007

The most advanced oxidation processes (AOPs) are based on reactivity of strong and non-selective oxidants such as hydroxyl radical (${\cdot}OH$). Decomposition of typical DNAPL chlorinated compounds (TCE, PCE) using various advanced oxidation processes ($UV/Fe^{3+}$-chelating agent/$H_2O_2$ process, $UV/H_2O_2$ process) was approached to develop appropriate methods treating chlorinated compound (TCE, PCE) for further field application. $UV/H_2O_2$ oxidation system was most efficient for degrading TCE and PCE at neutral pH and the system could remove 99.92% of TCE after 150 min reaction time at pH 6($[H_2O_2]$ = 147 mM, UVdose = 17.4 kwh/L) and degrade 99.99% of PCE within 120 min ($[H_2O_2]$ = 29.4 mM, UVdose = 52.2 kwh/L). Whereas, $UV/Fe^{3+}$-chelating agent/$H_2O_2$ system removed TCE and PCE ca. > 90% (UVdose = 34.8 kwh/L, $[Fe^{3+}]$ = 0.1 mM, [Oxalate] = 0.6 mM, $[H_2O_2]$ = 147 mM) and 98% after 6hrs (UVdose = 17.4 kwh/L, $[Fe^{3+}]$ = 0.1 mM, [Oxalate] = 0.6 mM, $[H_2O_2]$ = 29.4 mM), respectively. We improved the reproduction system with addition of UV light to modified Fenton reaction by increasing reduction rate of $Fe^{3+}$ to $Fe^{2+}$. We expect that the system save the treatment time and improve the removal efficiencies. Moreover, we expect the activity of low molecular organic compounds such as acetate or oxalate be effective for maintaining pH condition as neutral. This oxidation system could be an economical, environmental friendly, and practical treatment process since the organic compounds and iron minerals exist in nature soil conditions.

• Mycobiology
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• v.38 no.4
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• pp.295-301
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• 2010

We evaluated the antioxidant activity and tyrosinase inhibitory effects of Pleurotus ostreatus fruiting bodies extracted with acetone, methanol, and hot water. The antioxidant activities were tested against $\beta$-carotene-linoleic acid, reducing power, 1,1-diphenyl-2-picrylhydrazyl free radical scavenging activity, and ferrous chelating ability. Furthermore, phenolic acid and flavonoid contents were also analyzed. The methanol extract showed the strongest $\beta$-carotene-linoleic acid inhibition as compared to the other exracts. The acetone extract (8 mg/mL) showed a significantly high reducing power of 1.54 than the other extracts. The acetone extract was more effective than other extracts for scavenging on 1,1-diphenyl-2-picrylhydrazyl radicals. The strongest chelating effect (85.66%) was obtained from the acetone extract at 1.0 mg/mL. The antioxidant activities of the extracts from the P. ostreatus fruiting bodies increased with increasing concentration. A high performance liquid chromatography analysis detected seven phenolic compounds, including gallic acid, protocatechuic acid, chlorogenic acid, naringenin, hesperetin, formononetin, and biochanin-A in an acetonitrile and 0.1 N hydrochloric acid (5 : 1) solvent extract. The total phenolic compound concentration was $188{\mu}g$/g. Tyrosinase inhibition of the acetone, methanol, and hot water P. ostreatus extracts increased with increasing concentration. The results revealed that the methanol extract had good tyrosinase inhibitory ability, whereas the acetone and hot water extracts showed moderate activity at the concentrations tested. The results suggested that P. ostreatus may have potential as a natural antioxidant.

• Korean journal of food and cookery science
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• v.32 no.4
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• pp.466-475
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• 2016

Purpose: This study investigated the quality characteristics and antioxidant effects of Yakju added with rose, camellia, or cockscomb flower during fermentation. Methods: The quality characteristics and antioxidant effects were estimated including pH, amino acidity, total acid, ethanol content, color value, sensory test, electric donating ability, nitrite-scavenging ability, and ferrous ion chelating effect. Results: The pH values of Yakjus added with rose, camellia, or cockscomb flower were decreased after 2 days of fermentation and then increased after 4 days of fermentation, with final pH ranging from 4.15 to 4.27. Total acid content and amino acidity were increased during fermentation. The ethanol content in Yakjus fermented with rose, camellia, or cockscomb flower was rapidly increased after 2 days of fermentation, reaching the maximum content of 19.1% after 8 days of fermentation. In color evaluation, the L values of Yakjus added with rose, camellia, or cockscomb flower did not changes during fermentation, whereas values of a and b were increased. Total phenolic compound contents in Yakjus added with rose, camellia, or cockscomb flower were 0.67, 0.59, and 0.52 mg/mL, respectively. Total flavonoid contents in Yakjus added with rose, camellia, or cockscomb flower were 0.20, 0.09, and 0.26 mg/mL, respectively. In sensory test, the overall acceptability of Yakjus added with cockscomb flower was higher than that of Yakju added with rose or camellia flower. However, the difference was not statistically significant (p<0.05). Electron donating ability and nitrite-scavenging abilities were the highest in Yakjus added with rose flower, whereas ferrous ion chelating effect was the highest in Yakjus added with cockscomb flower. Conclusion: These results indicated that Yakjus added with rose, camellia, or cockscomb flower might have valuable functional properties due to their antioxidant effects.

• Analytical Science and Technology
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• v.11 no.1
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• pp.8-12
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• 1998

The 2,2'-Biimidazole was synthesized by the reaction between glycol and ammonium solution. The correct solid structure of 2,2'-biimidazole in this method reported either trans ($C_{2h}$) or cis ($C_{2v}$) form. In this study, the correct structure of 2,2'-biimidazole was analysed by both FTIR and Raman spectroscopy using mutual exclusion properties of them. Also, it was analysed by $^1H$ and $^{13}C$ NMR and computer molecular modeling. The structure of 2,2'-biimidazole found to be trans ($C_{2h}$) than cis ($C_{2v}$) by comparison between FTIR and Raman Spectra. This results agree with computer molecular modeling and x-ray crystallography. This study provide good evidence for identifying structural orientation of the 2,2'-biimidazole containing pyridyl nitrogen.