• Korean Journal of Food Science and Technology
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• v.21 no.4
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• pp.492-497
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• 1989

The antioxidant effects against linoleic acid of various protein hydrolysates from fish protein, defatted soybean cake, egg albumin and casein were investigated. Each protein hydrolysate by enzyme hydrolysis exhibited the antioxidative effects by addition of 5mg and 10mg per 1g linoleic arid. Especially, egg albumin and fish protein hydrolysates had a great antioxidative effects. The protein hydrolysates indicated the synergitic effects with ${\alpha}-tocopherol$, and indicated scavenging effects toward metal ion $(Fe^{3+},\;Cu^{2+})$ as prooxidants.

• Journal of the Korean Applied Science and Technology
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• v.34 no.3
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• pp.555-561
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• 2017

This study was conducted to investigate the several physicochemical extraction characteristics and the antioxidant activities of ethanol extract from Rhus javanica bark. The contents of soluble solid and sugar in extract was measured to 73.5 mg/100g dry basis and $17.8^{\circ}Brix$, respectively. The contents of total aromatics, total flavonoids and total phenolic compounds was measured to 0.508 in absorbance, 49.88 mg/100g and 296.6 mg/100g, respectively. The reducing power of extract was about 27.5 % of ascorbic acid with the same soluble solid contents of the extract. But the ferric reducing antioxidant power and the DPPH radical scavenging ability of extract were measured to equivalent to those of ascorbic acid. The metal ion chelating ability of the extract was 81.58 % whereas that of ascorbic acid was 74.73 %. The nitrite scavenging ability of the extract was measured to 51.76 % at pH 2. And the antioxidative effect of the extract on soybean oil was observed with Rancimat test.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.2
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• pp.527-534
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• 2019

Japanese sumac (Rhus javanica) is one of the common herbaceous plants growing over the country. This study was conducted to investigate the extraction characteristics and physiological activities inluding nitrite scavenging ability of the water extracts from leaf, fruit and bark of Japanease sumac. Extraction yield was 6.62~13.84%, free amino acids were detected as 24 kinds with 37.9 mg/100g in leaf extract, 23 kinds with 27.0 mg/100g in fruit extract and 27 kinds with 39.0 mg/100g in bark extract, respectively, and seven kinds essential amino acids were detected. Total contents of flavonoids equivalent to naringin were 587.2 mg/100g in bark extract, 557.3 mg/100g in fruit extract and 379.9 mg/100g in leaf extract, respectively. Total contents of phenolics equivalent to gallic acid were 111.2 mg/100g in leaf extract, 108.4 mg/100g in fruit extract and 80.4 mg/100g in bark extract, respectively. The nitrite scavenging ability of extracts was order of 61.93% in bark extract>57.38% in fruit extract>55.49% in leaf extract, and was 78.1~100% of those of BHT (butylated hydroxytoluene) equivalents at pH 1.2. The electron donating ability was order of 47.38% in fruit extract>43.06% in leaf extract>38.55% in bark extract, and was compared to 65.6%, 58.8% and 53.6% of those of BHT equivalents, respectively. The reduction power was evaluated to 37% higher in leaf extract, 43% higher in fruit extract and 46% higher in bark extract than those of BHT equivalents. The metal chelating ability of extracts was considerably low and was order of 27.3% in bark extract>20.6% in leaf extract>11.2% in fruit extract.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.6
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• pp.1097-1101
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• 2002

This study was conducted to investigate the efficacy of antioxidant ability and nitrite scavenging ability of Poria cocos Poria cocos mycelium and Poria cocos fermented with rice were extracted with water and ethanol for measurement of degree of fat acidification against fish oil. Lower TBARS values of Poria cocos mycelium and Poria cocos fermented with rice were shown compared with control. Iron chelating ability of Poria cocos mycelium against Fe$^{2+}$, Cu$^{2+}$ was higher than Poria cocos fermented with rice. Electron donating abilitv of water extract and ethanol extract of Poria cocos mycelium were 76.8% and 79.9%, respectively. Higher nitrite scavenging ability was shown at ethanol extract than water extract of Poria cocos mycelium.ium.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.5
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• pp.842-849
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• 1997

This study was designed to investigate the antioxidative activity of enzymatic hydrolysates prepared from defatted anchor muscle by various pretenses. In these hydrolysates, the hydrolysates derived from pepsin and Protamex showed the strongest antioxidative activity. Enzymatic hydrolysates also showed the synergistic effects on antioxidative activity of $\alpha-tocopherol$, and almost no change in butylated hydroxytoluene (BHT). Peroxidation of metal ions $(Fe^{3+},\;Cu^{2+})$ was inhibited by enzymatic hydrolysates. Ten fractions (P-1 to P-10) were fractionated from the peptic hydrolysates by Amberlite IR-120 and Bio-gel P-2 column chromatography. The maximum antioxidative activity was observed in the traction P-2 (fraction No. $26\~31$). In amino acid composition of before and after hydrolysis of defatted anchovy muscle and the active fractions (P-2), contents of aspartic arid and glutamic acid were increased, but alanine, cysteine, tyrosine and phenylalanine were decreased.