• Food Science and Preservation
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• v.13 no.2
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• pp.119-124
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• 2006

This study was conducted to optimize roasting process of Job's tears for utilization as food Optimal condition for masting was investigated with changes in temperature and time by response surface methodology. The qualities of water extract such as browning degree, polyphenol and DPPH radical scavenging ability were affected more by roasting temperature than time. The values increased with temperature and time proportionally. The response variables were more significant with temperature than time and the established polynomial model was suitable (P>0.05) model by Lack-of-Fit analysis. Optimal roasting conditions with the limit of $0.2{\sim}0.3$ browning degree, $2.0{\sim}2.5{\mu}g/mL$ polyphenol, $30{\sim}40%$ scavenging ability and $0{\sim}100$ hue angle were $215^{\circ}C$ and 32 min.

• The Korean Journal of Food And Nutrition
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• v.26 no.2
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• pp.280-286
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• 2013

This study was performed to investigate the effect of types of microorganisms on the antioxidant activity of soybean yogurt by a single or mixed culture of Bacillus subtilis and Lactobacillus plantarum isolated from chunggukjang and kimchi. The fermented soybean milk by Bacillus subtilis exhibited the highest values of total polyphenol, DPPH radical scavenging activity, reducing power and nitrite scavenging activity compared to those of Lactobacillus plantarum or mixed culture of Bacillus subtilis/Lactobacillus plantarum. As the amount of tomato extract was added to the soybean milk, various antioxidant parameters, such as total polyphenol, DPPH radical scavenging activity, reducing power and nitrite scavenging activity, were linearly increased.

• Journal of Mushroom
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• v.16 no.1
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• pp.9-15
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• 2018

This study aimed to characterize the mycelial morphologies of Hericium erinaceus isolates, including 18 wild-type collections and cultivatable species 'Noru 1' and 'Noru 2', in Korea. The morphological characteristics were used to classify the species based on aerial or branched mycelia and their brownish or whitish colors when grown on potato dextrose agar. Of the wild-type collections, the isolates KFRI 509, KFRI 1091, KFRI 1093, and KFRI 1623 showed faster mycelial growth than the cultivars 'Noru 1' and 'Noru 2'. Moreover, 60% ethanol extracts of the fruiting body of the mushroom showed the highest phenol content and DPPH and ABTS radical scavenging activity. The DPPH and ABTS radical scavenging activities of KFRI 507, KFRI 508, KFRI 842, and KFRI 1623 were 10-60% higher than those of 'Noru 1' and 'Noru 2', depending on the extract concentrations. Thus, results suggest that these wild-type collections could be useful for breeding genetic sources or processed food materials with high antioxidant activity.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1216-1220
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• 2003

The antioxidative activities of methanol extracts of chestnut flower (Castanea Crenata Flos.) were determinated in vitro using an experimental model system. Solid yield of chestnut flower extracts was 6.26% and total phenolic acid accounted for about 20% of the crude extract. The DPPH radical scavenging activity of methanol extracts prepared from chestnut flower was 17.22%. Although the DPPH radical scavenging activity of chestnut flower extracts was lower than that of other antioxidants, chestnut flower extracts showed continuous activity by time course. The SOD-like activities of methanol extracts prepared from chestnut flower were 65.10%, 95.70% in BHT, 93.29% in quercetin, and 30.30% in ascorbic acid. Chestnut flower extracts showed 51.45% inhibitory effect on peroxidation of egg yolk lecithin.

• 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 Life Science
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• v.17 no.9 s.89
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• pp.1237-1243
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• 2007

This study was investigated on the antioxidant capacity of 80% ethanol extract of lotus root in vitro. The ex-traction yields of 80 % ethanol extract was 9.14%. Lotus root ethanol extract was fractionated by the following: n-hexane, chloroform, ethylacetate and n-butanol. n-Butanol fraction showed the highest ex-traction yield of all fractions. Antioxidative activities of different fractions were examined by l.l-diphenyl-2-picrylhydrazyl(DPPH) radical generation, the Rancimat test, the nitrite scavenging ac-tivity and the thiobarbituric acid(TBA) method, and compared with the properties of the commercial antioxidant butylated hydroxytoluene(BHT). The antioxidative capacity of the ethylacetate fraction was the highest among fractions and its fraction showed higher contents of total polyphenol. Furthermore, the antioxidative capacity of the ethylacetate fraction was similar to that of BHT. In conclusion, these results suggest that lotus root may be a good candidate as a natural antioxidant source.

• Korean Journal of Food Science and Technology
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• v.46 no.5
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• pp.601-608
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• 2014

In this study, we investigated the antioxidant activity of green kohlrabi juice (GKJ) and purple kohlrabi juice (PKJ) using various in vitro methods. The results of 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging activities, ferric ion reducing antioxidant power (FRAP), reducing power, and nitrite scavenging activities showed that GKJ possessed higher antioxidant activity than PKJ. Green kohlrabi powder (GKJP) and purple kohlrabi powder (PKJP) inhibited hydrogen peroxide-induced cell death in human dermal fibroblasts. In addition, GKJP and PKJP suppressed intracellular reactive oxygen species (ROS) production induced by hydrogen peroxide in human dermal fibroblasts. These results suggest that green and purple kohlrabi juices are potential natural sources of antioxidants.

• Korean Journal of Food Science and Technology
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• v.53 no.1
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• pp.55-62
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• 2021

This study was conducted to investigate the potential of sea buckthorn leaf (SBL) as a natural antioxidant. SBL was extracted using different ethanol ratios (0, 40, 80, and 100%), and the resulting extracts were examined for their antioxidant contents and antioxidant activities using various methods. The 40% and 80% ethanol extracts (EEs) showed higher total polyphenol contents of 285.06 and 285.64 mg GAE/g respectively, than those in other solvents, and as the ethanol concentration increased, other antioxidant contents of the extracts increased. The 40% and 80% EEs recorded the highest radical scavenging activities against DPPH, superoxide-, ABTS+, nitrite scavenging activity (NO-), and reducing power (RP). The NO- and RP of the SBL EEs were higher than those of ascorbic acid or tannin, which are known as representative antioxidants. The results of this study, suggest that SBL is a potential source of natural antioxidants.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.2
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• pp.159-164
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• 2010

The present experiments were carried out to develop new antioxidants from EtOH extract of flower resources of Compositae plant concerning total polyphenol and flavonoid content, scavenging activities on DPPH and ABTS radicals, ferrous ion chelating effects, and inhibition activity on lipid peroxidation of linoleic acid. EtOH extracts from Matricaria recutica, Cosmos bipinnatus, Synurus deltoides, and Aster pilosus showed higher level of total polyphenol content, and the flavonoid content was the highest in C. bipinnatus. However, scavenging activity on DPPH radicals was the highest in EtOH extract of Hieracium pilosella-1.1 times higher than BHT control. The activity on ABTS radical scavenging was the highest in EtOH extracts of M. recutica and S. deltoides-2.0 and 1.2 times higher than ascorbic acid, and 2.2 and 1.3 times higher than BHT, respectively. Ferrous ion chelating effects was also the highest in M. recutica, but the level was much lower than EDTA. Inhibition activity on lipid peroxidation of linoleic acid, measured at every 4 days for 32 days, was superior and longer lasting with M. recutica and Achillea alpina, compared to that of BHT. In conclusion, antioxidant activity was different depending on species, so selection of proper plant species for the development of potential antioxidant is very important.

• Korean Journal of Food Science and Technology
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• v.44 no.4
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• pp.493-497
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• 2012

The objective of this study was carried out in order to evaluate the antioxidative activities of n-hexane fractions from medicinal herbs. Certain parts from 6 species of edible and medicinal herbs were extracted with methanol. Radical scavenging activity of the n-hexane fractions against DPPH and ABTS radicals were observed to be high in Psoralea corylifolia, and Scutellsria barbata; it also significantly increased (p<0.05). For a comparison of the effect of various concentration of fractions, as the concentration of treatment increased, the antioxidative effects on radical scavenging activity also oncreased; yet it was not significant. The antioxidative effect of medicinal plants was dependent on the concentration but was not significant. Therefore, these results indicate that edible wild plants, such as Psoralea corylifolia, and Scutellsria barbata may be useful as potential antioxidant sources for improving the human antioxidant defense system against disease.