• Korean Journal of Food Science and Technology
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• v.22 no.1
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• pp.61-65
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• 1990

Comparison of induction times among the Rancimat Method, the Oven Test and the Weight Method were investigated, and the oxidation stability of perilla oil was determinated by the Rancimat Method. The induction times determinated by three methods using perilla oil show a good correlation. And the temperature dependence of the induction times of perilla oil was as follows. $t_p=e^{-0.0815T+9.183}$. The antioxidant effect of Tocopherols on the oxidation of perilla oil was not observed, and the antioxidant effect of the organic acids was increased in the order of Ascorbic acid>Ascorbyl stearate>Malic acid>Tartaric acid>Citric acid. The synergistic effect of Ascorbic acid (500 ppm)and Tocopherols was not observed below 200ppm of Tocopherols, but became larger with increasing Tocopherols level over 200ppm.

• Bulletin of the Korean Chemical Society
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• v.31 no.6
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• pp.1751-1752
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• 2010

• Korean Journal of Plant Resources
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• v.17 no.1
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• pp.14-19
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• 2004

Aerial parts of Compositae plants were harvested from pastures and crop fields of Sunchon area at vegetative stage to determine their antioxidant activity. Among 13 species, three species Taraxacum officinate, Breea segeta, and Artemisia princeps were selected as potent plant materials. Through measurement by Rancimat and TBARS method, antioxidative effect was the greatest in Taraxacum officinate among plant species. Antioxidative index (AI) investigated by Rancimat showed Siegesbeckia glabrescensi was 1.51 while commonly-used antioxidants, BHT and ascorbic acid were 3.86 and 2.43, respectively. The highest TBARS value was also obtained from Taraxacum officinate(0.18) at 4 weeks after storage, indicating the plant had the strongest antioxidant activity during long time. Even though TBARS value (0.18) in Taraxacum officinate sample showed lower in all plants than two synthetic antioxidants(0.05-0.09), antioxidant activities of the plants were much higher than that of a control (1.01). The results suggest that the plants have antioxidant potential as an alternative natural antioxidant based on natural plant resources.

• Journal of Food Hygiene and Safety
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• v.7 no.2
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• pp.107.1-112
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• 1992

Free-, soluble- and insoluble phenolic acids were extracted from defatted Galla Rhois. The extracts were then dissolved in equal amounts of an soybean oil, and POV (peroxide value) of the resulting substrates, portion of the soybean oil (control) and 0.02% BHT were measured by AOM (active oxygen method) test at 97.8$^{\circ}C$ for 40 hours through Rancimat method. Induction period of control, BHT, free phenolic acids, soluble phenolic acids and insoluble phenolic acids by the Rancimat method were 4.8, 10.5, 23.9 and 30.5hr. The phenolic acids separated and tentati-vely identified by gas chromatography were catechol, gallic acid, vanillin, protocatechuic acid, syri-ngic acid, ferulic acid.

• YAKHAK HOEJI
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• v.47 no.4
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• pp.212-217
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• 2003

We have carried out the antioxidative activity of nuts species for the development of antioxidant from natural products. From our previous report, EtOAc and n-BuOH extracts of acorn hull and chestnut hull were found to have a strong antioxidative activity in various antioxidant experiment. In the continuous study, we isolated several compounds from EtOAc and n-BuOH extracts of acorn hull and chestnut hull by fractionation using column chromatography. The structures of isolated compounds were identified as catechin, naringenin and ellagic acid on the basis of their spectroscopic properties and by comparison of their physical and spectra data with published value. Antioxidative activities of catechin, naringenin and ellagic acid were measured by DPPH, ferric-thiocyanate and Rancimat method.

• Journal of Nutrition and Health
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• v.31 no.8
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• pp.1355-1364
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• 1998

This study was planned to investigate the effect of 40 plant ethanolic extracts on antioxidant activities in vitro. The total phenolics, $\beta$-carotene, $\alpha$-tocopherol and selenium contents were also determined . Antioxidant activities fo the ethanolic extracts(0.02%, w/w) in the soybean oil were measured both by determining the peroxide value (POV) during 35 days of storage at 4$0^{\circ}C$ in a forced draft air-incubator and by determining changes in conductivity at 11$0^{\circ}C$(Rancimat method.). Soybean oil without any additives was used as a control and that treated with 0.02% BHT was used as a positive control. Based on the POV determination, green tea extract was found to be the most effective in stabilizing soybean oil, then followed by long tea, which both of them showed higher antioxidant activities compared to the BHT treatment. The antioxidant activities of them showed higher antioxidant activities compared to the BHT treatment. the antioxidant activities of coffee, cinnamomi cortex, acanthopanacis cortex, black tea, orange peel , instant coffee, peony and crni fructus extracts were stronger compared to the control .By the Rancimat method, green tea leaf and oolong tea leaf, foxglove, acanthopanacis cortex and peony extracts. Compared to other extracts, green tea leaf, black tea leaf, foxglove, acanthopanacis cortex and peony extracts had stronger antioxidative effects in both the POV and Rancimat methods used in this study. ethanolic extracts which showed the stronger antioxidative effect also has the higher contents of total phenolics, $\beta$-carotene, and/or $\alpha$-tocopherol. The antioxidative effect of ethanolic extracts was found to be due to the combined effect of various antioxidants.

• Korean Journal of Medicinal Crop Science
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• v.12 no.4
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• pp.289-294
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• 2004

Reactive oxygen species (ROS) are continuously produced at a high rate as a by-product of aerobic metabolism. Several lines of evidence provided that ROS appears to cause to develop aging and various diseases. High level of hyaluronic acid with decreased molecular weight has been detected in patients with inflammatory diseases including rheumatoid arthritis. In this study, we have conducted to investigate the antioxidant and hyaluronidase inhibitory activities of Prunus persica Batsch var. davidiana Maximowicz in order to screen the bioactive substances which can be developed as possible anti-inflammatory agents. Among the extracts of Prunus persica Batsch var. davidiana Maximowicz, EtOAc extract exhibited the strongest effect on antioxidant experiment such as DPPH, Ferric- Thiocyanate and Rancimat. Also, EtOAc extract showed a potent hyaluronidase inhibitory activity.

• Food Science and Preservation
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• v.13 no.6
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• pp.726-731
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• 2006

Extract from forty four species of natural plants in Korea were obtained. Each extinct (1,000 ppm) was added into fish oil and their antioxidative activities were screened by rancimat, From the results, seven species including Brassica juncea, Solanum tuberosum, Capsella bursa, Ulums davidiana, Broussonetia kazinoki, Oenanthe javanica, and Rhus chinensis were selected due to their relatively prolonged induction periods. When the concentration (100 - 1,000 ppm) of the selected extract was considered, the most prolonged induction period was observed from Solanum tuberosum throughout the studied concentrations, suggesting that its extinct showed the strongest antioxidative activity against fish oil. In addition, peroxide value (POV) and thiobarbituric acid reactive substance (TBARS) value were considered at $60^{\circ}C$ for 5 days. Among the selected extract, extract from Solanum tuberosum showed the lout POV while the extract from Brassica juncea var showed the least TBARS values after 5 days. Also, the free radical scavenging effect against DPPH radical were studied with the selected extract, showing that the extract from Rhus chinensis was found to be the most effective.

• Korean Journal of Food Science and Technology
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• v.26 no.5
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• pp.622-626
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• 1994

Propolis was extracted by several organic solvents, and the antioxidative effect of the extracts on palm oil and lard was tested with the extract solely or combined with some synergists, using the Rancimat Method. The extraction yields of propolis by each solvent were 68.1% (75% ethanol), 75.5% (99% ethanol), 67.4% (methanol;, 86.7% (chloroform), 72.6% (ethyl acetate) and 65.6% (butanol). AI (Antioxidative Index; induction p-eriod of oil containing antioxidant/induction period of natural oil) of the methanol extract was highest, and more effective on lard than palm oil. The ethyl acetate fraction of 75% ethanol extract showed higher antioxidative effect than 75% ethanol extract, and obtained the highest antioxidative effect on palm oil with ascorbic acid as synergist and lard with ${\dalta}-toocopherol$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.2
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• pp.207-210
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• 2003

This study was designed to investigate the antioxidative effect of glasswort (Salicornia herbacea L.) grown in closed sea beach. To compare antioxidant effects of glasswort plant parts, dried ground leaves, stems, and roots of glasswort were exploited for investigation of antioxidant activity Antioxidant activity for the samples was investigated by Rancimat and TBA method. The oxidative stability determined by the Rancimat technique showed a variation in antioxidative index (AL) between the different plant parts, ranging from 1.0 to 3.6. Oxidative stability from ground stem sample of glasswort harvested in the closed sea beach was the highest, and followed by leaf and root. Stem had higher oxidative stability than ascorbic acid. Antioxidatiue effects of glasswort were increased in dose-dependent manners, and antioxidant activity by addition of glasswort with same amount to 4% oil was similar to the activity of ascorbic acid. Specially, 8~10% glasswort addition to oil showed similar antioxidative effect to 1% $\alpha$-tocopherol.