• Food Science of Animal Resources
• /
• v.22 no.1
• /
• pp.13-19
• /
• 2002

The natural sources extracted from green tea and pine needle were utilized to investigate the effects of extracts on free radical reaction, lipid oxidation and nitrite scavenging ability. The degree of lipid oxidation is very sensitive to kinds of oil emulsion reacted with iron sources and oxygen species. The antioxidants of extracts from green tea and pine needle were different depending on concentration of extracts, which were a lower TBARS value in 0.3% extracts concentration, compared to 0.1% extracts concentration. And also, the binding ability on iron sources was superior in hot water extracts, but oxygen scavenging ability was the lowest TBARS values in ethanol extracts. The hydroxyl radical scavenging ability of green tea and pine needle extracts had a little low TBARS value in 0.1% and 0.3% extracts concentration in deoxyribose. The ethanol extracts of pine needle were higher than those of hot water extracts on the basis of Fe$\_$2+/ ion content. The ascorbic acid content of green tea showed 14.3 mg/100g in hot water extracts and 16.7 mg/100 g in ethanol extracts. Electron donating ability of extracts showed difference depending on extracts concentration, which were higher in ethanol extracts than those of hot water extracts. The nitrite scavenging effects were tended to be different depending on pH value, however they were decreased overall as pH value was increased. Especially, the nitrite scavenging ability of 0.3% extracts from green tea and pine needle were the mosts effective in pH 1.2 and pH 3.0, which were showed 95% nitrite scavenging ability.

• Korean Journal of Food Science and Technology
• /
• v.28 no.2
• /
• pp.232-239
• /
• 1996

Phenolic compounds are known to inhibit the nitrosation or oxidation reaction. In the present work, the effects of phenolic compounds including phenolic acids and flavonoids on the nitrite-scavenging and electron donating ability were tested as scavenger of nitrite which is believed to participate in the formation of N-nitroso compounds and investigated as electron donator. The nitrite scavenging ability appeared in all the phenolic acids and showed the highest value at PH 1.2. Among the Phenolic compounds, phenolic acids showed higher nitrite-scavenging action than some flavonoids. Futhermore, the nitrite scavenging action of phenolic compounds was pH dependent highest at pH 1.2 and lowest at pH 6.0. The electron donating ability (EDA) by reduction of ${\alpha},{\alpha}$-diphenyl-${\beta}$-picrylhydrazyl (DPPH) among hydroxybenzoic acids was in the decreasing order of gallic acid, gentisic acid, syringic acid, protocatechuic acid, salicylic acid, vanillic acid, benzoic acid and p-hydroxybenzoic acid. EDA of hydroxycinnamic acids was in the decreasing order of hydrocaffeic acid, caffeic acid, ferulic acid, p-coumaric acid and trans-cinnamic acid. EDA of flavonoids was in the decreasing order of (+)catechin, rutin, quercetin, naringin and hesperidin. Other phenolic compounds were significantly high in electron donating abilities.

• Journal of Applied Biological Chemistry
• /
• v.53 no.1
• /
• pp.8-12
• /
• 2010

The antioxidant activity of hawthorn fruit (Crataegus pinnatifida Bunge var. typica Schneider) extracts was investigated by several in vitro antioxidants properties, including DPPH free radical scavenging activity, total phenolic and flavonoid contents, hydroxyl radical scavenging activity, reducing power activity, iron-chelating capacity and nitrite scavenging activity. Among the extracts in this study, the 70% EtOH extract showed higher antioxidant activity than the others. The $IC_{50}$ value of DPPH free radical scavenging activity was $99.26\;{\mu}g/mL$. Furthermore, the 70% EtOH extract also showed significantly high total phenolic and flavonoids contents and reducing power activity. However, the MeOH extract exhibited stronger effects on hydroxyl radical scavenging activity, iron-chelating capacity and nitrite scavenging activity. All the results implicated that, the hawthorn fruit may has the available potential to be utilize as a potential source of natural antioxidant.

• Korean Journal of Medicinal Crop Science
• /
• v.21 no.4
• /
• pp.255-261
• /
• 2013

The purpose of this study was to examined the antioxidant activities by water and 70% ethanol extract from durian (Durio zibethinus.) seed, sarcocarp and peel. Durian extract were studied for reducing sugar content, polyphenol content, superoxide dismutase (SOD) like activity, electron donating ability, nitrite scavenging ability, flavonoid content, hydroxy radical scavenging activity. Reducing sugar content were increased peel > sarcocarp > seed. Total polyphenol, flavonoid content, DPPH radical scavenging ability and SOD like activity were increased seed > peel > sarcocarp. Total polyphenol content was relatively high as $21.90{\pm}0.50mg/g$ in the ethanol extract of the seed. DPPH radical scavenging ability was relatively high as $62.08{\pm}2.63%$ in the water extract of the seed. Nitrite scavenging ability was no significant difference. Hydroxy radical scavenging activity was increased seed > peel > sarcocarp, was relatively high as $58.27{\pm}1.13%$ in the water extract of the seed.

• Food Science and Biotechnology
• /
• v.15 no.3
• /
• pp.351-356
• /
• 2006

In this study, we investigated the effect of adding a 1, 3, or 5% solution of germinated brown rice concentrate (GBRC) to fermented kimchi. During fermentation, the concentration of free amino acids and essential amino acids increased with increasing concentrations of GBRC. In particular, higher levels of free amino acids were associated with a sweet taste compared with controls. The ${\gamma}$-aminobutyric acid (GABA) content of kimchi containing the 5% GBRC solution was 3 times higher than that of controls. The total phenolic compound content (130 mg%) did not change significantly in the control group, but increased in 10 mg% increments as the GBRC concentration rose from 1 to 3 to 5%. 2,2-diphenyl-1-picryhydrazyl (DPPH) free radical scavenging activity and superoxide radical scavenging activity also increased with the GBRC concentration, with maximum activity during the ripe stage with GBRC measured at 79 to 82% compared with controls (30 to 71 %). The nitrite scavenging activity was 10% higher with GBRC compared with controls and was highest when the pH was 1.2. These results showed that the addition of GBRC is effective in improving the function of kimchi.

• Korean Journal of Food Science and Technology
• /
• v.32 no.4
• /
• pp.942-948
• /
• 2000

Nitrite scavenging activity of Kimchi added with salted-fermented fish products(SFFP), such as low salt-fermented anchovy sauce(LSFAS), salted-fermented anchovy sauce(SFAS), salted-fermented anchovy(SFA), salted-fermented small shrimp(SFS), low salt-fermented sandlance sauce(LSFSS) and their alternatives, such as oyster hydrolysate(OH), Alaska pollack hydrolysate(APH) and Sea-staghorn extract(SSE) were studied during fermentation at $20^{\circ}C,\;10^{\circ}C\;and\;4^{\circ}C$. Nitrite contents of Kimchi samples added with SFFP were roughly decreased except Kimchi added with SFS and SFAS, which increased at the 2nd day of fermentation. Fermentation of Kimchi at $4^{\circ}C\;and\;10^{\circ}C$ resulted a decrease in nitrite(<5 ppm). Nitrite contents of Kimchi samples added with SFFP alternatives rapidly decreased in the initial fermentation and then kept a low level (<2 ppm). Nitrite scavenging effects of Kimchi samples added with SFFP and their alternatives were steady during fermentation, showing a little variation in samples added with SFFP. Samples added with LSFAS and OH showed higher nitrite scavenging effects(90%) than others$(70{\sim}80%)$.

• Korean Journal of Plant Resources
• /
• v.26 no.4
• /
• pp.426-432
• /
• 2013

The results of the content of total polyphenol and flavonoid, DPPH (1-1-diphenyl-2-picryl-hydrazyl) radical scavenging activity, ABTS [2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)] radical scavenging activity, nitrite scavenging activity and SOD-like activity of methanol extracts from immature cotton boll are follows. The contents of total polyphenol and flavonoid compound were higher in small size cotton boll, and DPPH and ABTS radical scavenging activity also showed a relatively high activity in the small size. These results indicate that there is a correlation between phenol content and DPPH radical scavenging, ABTS radical scavenging. The test concentrations of immature cotton boll extract for measuring DPPH and ABTS radical scavenging activities were set as 1.25, 2.5, 5, 10 and 20 mg/ml. Immature cotton boll has high radical scavenging activity at the concentration of 1.25~20 mg/ml and the result showed a tendency to increase in a concentration-dependent. The nitrite scavenging activity showed high activity in the pH 1.2, and the result in the pH 4.2 showed progressively less active, and in the pH 6.0 near neutral was confirmed that does not affect the nitrite scavenging. In addition, SOD-like activity showed somewhat lower activity compared with ascorbic acid, but tended to be higher when compared with the results of the other natural substances. Through this experiment, we confirmed that immature cotton boll was excellent antioxidant activity. Therefore, it is demonstrated that the cotton suggest the possibility of development of new material for cosmetic product or functional food in the future, and is expected to make a greater usability.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.30 no.4
• /
• pp.589-593
• /
• 2001

The natural sources extracted from crab shell Korean tagnrine peel, sesame meals were utilized to investigate the effects of extracts on free radical reaction, lipid oxidation and nitrite scavenging ability. The recovery percentage of extracts from waste resources (crab shell, sesame meal, dry korean tangrine peel) were chitosan 11.6%, crude sesamol 2.2% and ascorbic acid 2.8%, respectively. The antioxidants were tended to have a lower TBARS value than those of control. The nitrite scavenging and electron donating ability of crude sesamol were tended to be the most effective extract among all extracts. However, In case of chitosan, the superoxide dismutase (SOD)-like activity was the most highest, compared to other extracts.

• Preventive Nutrition and Food Science
• /
• v.14 no.3
• /
• pp.195-200
• /
• 2009

This study was carried out to investigate the biological activities of star anise extracts obtained from four different solvents (water, methanol, ethanol and chloroform) by measuring total polyphenol and flavonoid contents, DPPH radical scavenging, hydroxyl radical scavenging, nitrite scavenging activity and antimicrobial activity. The methanol extract showed the highest extraction yield, followed by ethanol, water and chloroform. The properties of the extracting solvents significantly affected the total polyphenol content. Methanol extracts contained more total polyphenols than any other extracts. The highest DPPH radical scavenging activity was found in methanol extract. The hydroxyl radical and nitrite scavenging activity were highest in methanol and ethanol extracts. In antimicrobial activity, water extract showed stronger activities than methanol and ethanol extract against Micrococcus luteus and Bacillus subtilis, and no inhibitory effects on Gram negative bacteria were found in all extracts at the concentration used.

• The Korean Journal of Food And Nutrition
• /
• v.34 no.2
• /
• pp.181-186
• /
• 2021

Antioxidant properties and antioxidant activities were analyzed for water extracts and 50% and 70% ethanol extracts of the leaf of Angelica gigas Nakai. The polyphenol and flavonoid contents in water, 50%, and 70% ethanol extract of the leaf of Angelica gigas Nakai, it was found that the polyphenol contents were 18.75 mg GAE/g, 28.95 mg GAE/g, and 34.73 mg GAE/g, respectively, and flavonoid contents were respectively. The DPPH IC50 scavenging activity was 45.84 mg/mL, 36.44 mg/mL, 19.11 mg/mL, respectively, and theABTS+ radical scavenging ability (1 mg/mL) was 28.73%, 22.79%, and 12.70%, respectively. Tyrosinase inhibitory activity, 70% ethanol extract, 50% ethanol extract, and water extract 33.14%, and 4.53%, respectively. Nitrite scavenging activity, 70% ethanol extract, 50% ethanol extract, and water extract were in the order of 1 mg/mL scavenging activity, 36.43%, 34.80%, and 18.85%, respectively.