• Journal of Life Science
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• v.6 no.2
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• pp.104-110
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• 1996

The present study was conducted to elucidate the functional property of tea extract obtained from tea extracts, semi-fermented tea(oolong tea) and fermented tea(black tea). Tea extracts exhibited remarkable nitrite-scavenging actions, and the action increased with the increased of the amount of tea extracts. The nitrite-scavenging actionof tea extracts showed pH dependent, highest at pH 1.2 and lowest at pH6.0. The nitrite-scavenging rate in tea extracts/amine/nitrite systems proved to be faster than that in amine/nitrite systems. To screen the nitrite-scavenging factors, tea extracts were fractionated into water-soluble, methanol-soluble, methanol-precipitate and crude catechin fraction. Among these fractions of tea extracts, the crude catechin fraction possessed greater nitrite-scavenging action than the other fractions. The nitrite-scavenging action of tea extracts increased with the contents of total phenols and an absorbance at 280nm, nitrite-scavenging factors were supposed to be and catechins in tea polyphenol compounds.

• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.453-458
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• 1988

This research was carried out to investigate the effects of Maillard reaction products and nondialyzable melanoidins on the nitrite-scavenging. Nitrite-scavenging reactions were done at the different pH conditions(pH 1.2, 4.2 and 6.0). Maillard reaction products and nondialyzable melanoidins, produced from the glucose-amino acids(lys., gly., arg., his.)model systems, had a great of nitrite-scavenging effects. Nitrite-scavenging effects of Maillard reaction products and nondialyzable melanoidins were also pH dependent, being higher at pH 1.2 and lower at pH 6.0. By the treatment of Maillard reaction products and nondialyzable melanoidins with sodium borohydride, nitrite-scavenging effects were remarkably decreased at pH 1.2.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.526-529
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• 1993

The present study was conducted to investigate nitrite-scavenging ability of the components of Cassiae torae semen, Cassia tora L. The nitrite-scavenging effects of fractions obtained from methanol extract of Cassiae torae semen, Cassia tora L. were strong in ethyl acetate fraction, chloroform fraction, water soluble fraction and ethyl ether fraction in order. Compound D showed the strongest nitrite-scavenging effects among compound A, B, C, D separated from Cassiae torae semen. Compound D separated from Cassiae torae semen possessed ten-fold stronger the nitrite-scavenging effect than ascorbic acid.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.2
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• pp.287-292
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• 1994

This paper was investigated to elucidate the nitrite-scavenging action as one of biological actions of green tea extracts. Green tea extracts exhibited remarkable nitrite-scavenging action. Among the green tea extracts, steamed green tea showed higher nitrite-scavenging action than roasted green tea. Nitrite-savenging actions of gren tea extracts were hardly influenced until three times extraction with hot water. Furthermore , the nitirte-scavenging action of green tea extracts showed ph dependent , highest at pH 1.2 and lowest at pH 6.0. The nitrite -scavenging rate in sample extracts /amine /nitrite systems exhibited faster than that in amine/nitrite systems. In order to screen the nitirte-scavenging factors, samples extracts were fractionated with methanol. in both samples, methanol-soluble fractions possessed greater nitrite-scavenging action than methanol-insoluble fractions .The nitrite-scavenging action of methanol-soluble fractions increased with proportion to absorbance at 420nm and at 280nm, while that of green tea extracts increased with the contents of total phenols and absorbance at 280nm.

• Korean journal of food and cookery science
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• v.23 no.1 s.97
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• pp.19-24
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• 2007

This study investigated the antioxidant and synergistic effects and nitrite scavenging ability of some phenolic compounds(catechin, rutin, quercetin and naringin), The electron donating abilities of naringin, quercetin, rutin and catechin were 6.7%, 92.8%, 87.6% and 92.21%, respectively, The antioxidant activities in O/W emulsion substrates were in order of rutin > quercetin > catechin > naringin. The antioxidant effect of rutin was stranger than that of BHT or ${\alpha}$-tocopherol. ${\alpha}$-tocopherol showed synergistic effect with catechin and quercetin, but ascorbic acid not showed effect. The nitrite scavenging abilities of catechin, quercetin, rutin and naringin were 99.9%, 98.6%, 25.5% and 0.2%, respectively. The nitrite scavenging abilities of quercetin and actechin were very potent as compared with those of BHT and ascorbic acid.

• The Korean Journal of Food And Nutrition
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• v.11 no.4
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• pp.426-430
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• 1998

This study was conducted to investigate electron donating ability, antioxdative activity and nitrite-scavenging effect of solvent extracts from Gyrophora esculenta. The phenolic compounds of diethylether, butanol, petroleum ether and hexane extracts were 194.20$\mu\textrm{g}$/ml, 98.80$\mu\textrm{g}$/ml, 1.60$\mu\textrm{g}$/ml and 0.20$\mu\textrm{g}$/ml, respectively. Electron donating abilities of diethyleter and butanol extracts from Gyrophora esculaenta were 80.79% and 72.81%, respectively. Absorption of DPPH by diethyleter and butanol extracts sharply increaed at initial stage. Antioxidative activities of fiethylether and butanol extracts by peroxide values are rather high as compared to those of control, but low s compared to those of BHA. Nitrite-scavenging abilities of diethylether, butanol and petroleum ether from Gyrophora esculenta were 96.07%, 77.39% and 15.07%, respectively.

• Korean Journal of Plant Resources
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• v.29 no.3
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• pp.289-296
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• 2016

This study was executed to evaluate the immune activity, nitrite scavenging activity and ABTS radical scavenging activity against extracts of various concentration of ethanol solvent from Codonopsis lanceolata cultured at 6 local regions. The immune responses from both human T and B cell line was significantly enhanced in the cell growth compared to control while the cell growth was influenced at a certain period of culture. The results revealed that the cell growth of both human T and B cell was altered in a time dependent manner. The nitrite scavenging activity of ethanol extracts from various solvent concentration of C. lanceolata were affected by pH. At a pH of 1.2, the nitrite scavenging effect of all of the extracts tested observed higher than that of the other two pH ranges. There was no distinct detection of nitrite scavenging effects of the pH range 6.0. The ABTS radical scavenging activity was progressively increased in a dose-dependent manner, and the activity was the highest in 100% ethanol extract. The result from this investigation suggests that the extract of Codonopsis lanceolata could be an addition to basic medicine for immune modulation and natural food additives.

• Korean journal of food and cookery science
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• v.18 no.1
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• pp.8-12
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• 2002

The nitrite scavenging effect of three kinds of edible wild plants belong to Umbelliferaeceae family was investigated. The contents of crude protein, crude lipid and $\beta$-carotene of the plants were in the range of 22.99∼31.00%, 3.51∼5.08% and 5.40∼19.81 mg%, respectively. The content of ascorbic acid was very low and selenium was not detected in any samples. The contents of linoleic acid and linolenic acid were 66.46∼77.44%. The content of total phenol was 875.77 mg% in Ledebouriella seseloides WOLFF, which was the highest among the samples. The methanol fraction of the plant extract showed higher nitrite scavenging effect than the water fraction. The nitrite scavenging effects of the samples were the highest at pH 1.2 and lowest at pH 6.0, suggesting that it's pH dependent. Nitrite scavenging effect of methnol-soluble fractions obtained from Ledebouriella seseloides WOLFF was 95.3% at pH 1.2, which was the greatest among tested samples. There was a high correlation between the nitrite scavenging effect and the total phenol content.

• Journal of Life Science
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• v.8 no.5
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• pp.473-478
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• 1998

The radical scavenging activity of the methanol extracts was in the order of doenjang〉 meju〉 soybean. The metha-nol extracts were further fractionated with dichloromethane, ethyl acetate, butanol and water in sequence. Among the solvent fractions of the methanol extracts, the ethyl acetate fraction demonstrated high levels of radical scave-nging activity. On the other hands, the nitrite scavenging activity of the methanol extrats was in the order of doen-jang〉soybean〉meju. All fractions from doenjang were exhibited the strong nitrite scavenging effect. Especially, $H_2O$, EtOAc and BuOH fractions with 6gmg/10$m\ell$ concentration exhibited much stronger nitrite scavenging effect than that of L-ascorbic acid. The ethyl acetate fraction showed remarkable antioxidant and nitrite scavenging effects compared with the other fractions obtained from soybean, meju and doenjang. The ethyl acetate fraction of doenjang was fur-ther purified by repeated chromoatograpic methods and isolated three compounds. There are identified as genistin, dai-dzein and genistein on the basis of spectral data.

• Food Science and Preservation
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• v.9 no.1
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• pp.92-96
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• 2002

The nitrite-scavenging and antimutagenic effects of various solvent extracts from different parts of the loquat. were investigated to develope as source of functional food. The nitrite-scavenging and antimutagenic effects of fractions obtained from methanol extract were most highest in ethyl acetate fraction. Ethyl acetate fraction showed better results in the nitrite scavenging activity of 80% in leaf, 81% in seedless fruit, 73% in peel and 63% in seed. The antimutagenic effect showed strong ethyl acetate fraction of 53.1%, 48.3% in leaf and seedless fruit. The antimutagenic effect increased with increasing concentration of ethyl acetate fraction against mutagenicity induced by direct mutagen of IQ in Salmonella typhimurium TA 100. Addition of 2.5 mg and 5 mg of ethyl acetate fraction showed inhibitory effect of 65.5%, 71.2% in leaf and 63.4%, 69.2% in seedless fruit, respectively.