• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.3
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• pp.383-389
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• 1997

Doenjang(fermented soybean paste) was prepared by the series of processes including soaking, cooking, first fermentation(3 days at 30$\pm$2$^{\circ}C$) for the preparation of meju(soybean koji) after inoclulation of Aspergillus oryzae, and further fermentation (60 days at 30$\pm$2$^{\circ}C$) for the ripening after addition of salt 13% to meju. the crude phenolics extracted from defatted soybean and doenjang were fractionated onto the neutral phenolics(isofavonoids) and acidic phenolics(phenolic acids), respectively. Composition and antioxidative characteristics of phenolic fractions were determined. The neutral phenolic fractions contained genistin, genistein and daidzein; on the other hand, acidic phenolic fractions had syringic acid and seven other components. The content of genistin in doenjang dramatically decreased at the early stage of fermentation, whereas the content of genistein rather increased. In addition, the content of syringic acid of acidic phenolic fractions were increased during fermentation. These changes in individual phenolic components affected the antioxidative activity of neutral phenolics or acidic phenolics. antioxidative activity of phenolic compounds were evaluated during soybean fermentation. The antioxidative and free radical scavenging activity of neutral phenolic fractions and acidic phenolic fractions on linoleic acid autoxidation were also investigated.

• Food Science and Biotechnology
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• v.16 no.3
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• pp.451-456
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• 2007

The potential antioxidant activities of methanolic extracts from soybean and rice fermented with Monascus sp. were investigated. M. pilosus IFO 480 and M. anka IFO 478 were screened as a suitable strain to promote the antioxidant activities in soybean- and rice- fermentation. The methanol extracts from soybean and rice after fermenting for 20 days at $30^{\circ}C$ resulted in a significant increase in the antioxidant capacities expressed as radical (ABTS and DPPH) scavenging assay and peroxidation inhibition (%) by thiocyanate method and increased (p<0.01) by a 2.6 to 3.1-fold compared with those of the unfermented products. The average antioxidant potentials of Monascus-fermented soybean extracts (MFSE) were significantly (p<0.01) stronger than Monascus-fermented rice extracts (MFRE). A linear correlations between free radical scavenging activity of MFSE and the total phenolics content (r=0.84) and total flavonoids content (r=0.81) were observed. These results indicated that MFSE exhibited stronger (p<0.01) antioxidant activity and contained significantly higher levels (p<0.05) of phenolics than MFRE.

• Korean Journal of Food Science and Technology
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• v.52 no.4
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• pp.377-384
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• 2020

Paprika is a popular vegetable with high visual appeal and desirable flavor, the health benefits of which are increasingly attracting interest. In this study, the physical qualities, antioxidant content, and activities of six mini paprika cultivars were investigated. Both the edible part (flesh) and the by-products were studied. The average total phenolics and total antioxidant activities were higher in the flesh than in the by-products. The total flavonoids of the flesh and the byproducts were 16.41 and 37.80 mg/100 g FW, respectively. "YW glory" and "Raon yellow" flesh had the highest (245.52 mg/100 g FW) and lowest (179.96 mg/100 g FW) total phenolics among the six cultivars, respectively. However, the "RD glory" cultivar showed the highest total phenolic content (232.70 mg/100 g FW) among the by-product samples. The total phenolics in the flesh and by-products were highly correlated to the ABTS radical scavenging activity, with R=0.961 and 0.984, respectively.

• Korean Journal of Food Science and Technology
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• v.49 no.6
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• pp.714-716
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• 2017

Rose flower is widely used in the preparation of tea and contains a large variety of phytochemicals, including phenolics such as catechin, quercetin, and rutin. The effects of aging on rose (Rosa hybrida L.) flower extracts (RFE) were examined under conditions of varying temperature and relative humidity. The total phenolic content, antioxidative activity, and catechin levels were measured to evaluate the effects of temperature and relative humidity on the aging process. Performing the aging process at $30^{\circ}C$ under 60% or 90% relative humidity for 24 h significantly increased the total phenolic content and the antioxidant activities of RFE (p<0.05). Additionally, an aging process performed at $30^{\circ}C$ and 60% relative humidity for 24 h maximized the extraction rate of phenolics such as catechin and consequently led to increased antioxidative activity of RFE. In summary, this study indicates that the extraction rate of physiologically active phenolic compounds in rose flower can be increased by performing an aging process under optimized temperature and relative humidity conditions.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.3
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• pp.232-238
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• 2013

An experiment was conducted to determine the content of phenolics and flavonoids, antioxidant activity and antioxidant enzyme status for the extracts from 5 and 7-day old sprouts (DOS) of cowpea (Vigna unguiculata L. Walp). Total phenolics [mg ferulic acid equivalents (FAE) $kg^{-1}$ DW] content was highest in cotyledon extracts (48.8 mg $kg^{-1}$), followed by roots (30.8 mg $kg^{-1}$) and hypocotyl (22.2 mg $kg^{-1}$) extracts (p < 0.05) from 5 DOS. The result of total flavonoid level [mg rutin equivalents $kg^{-1}$ DW] had same tendency to the results of total phenolics, showing lower amount ranges. The antioxidant activity of the methanol extracts from all the plant dose-dependently increased. DPPH (1,1-diphenyl-2-picryl hydrazyl radical) free radical scavenging activity was higher in cotyledon extracts (82.5%) than in root (52.6%) or hypocotyl parts (35.0%) from 5 DOS. Among antioxidant enzymes, APX and CAT activities were highest in cotyledon part and POX and SOD activities in root part of 5 and 7 DOS. The results showed that total phenolics content ($r^2$ = 0.1516~0.9911) were more highly correlated with antioxidant activity than total flavonoids level ($r^2$ = 0.0113~0.9442), and that the level and activity of physiological-active substances were different depending on plant part of the sprout.

• Journal of Apiculture
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• v.32 no.4
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• pp.327-332
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• 2017

In this study, we studied the changes in antioxidant activity of Actinidia arguta fruit of Autumn Sense cultivar during fruit ripening. The aim of this investigation was to find the knowledge of the changes of physiochemicals associated with fruit quality, antioxidant properties (free-radical scavenging activity and reducing power), total phenolics and vitamin C during fruit ripening. The highest free-radical scavenging activity (at $100{\mu}g/ml$) and reducing power (at $100{\mu}g/ml$) in A. arguta fruit were 78.57% and 0.22, respectively. Total phenolic content and vitamin C content in fruit of 10 days after fruit set were $639.48{\mu}g/g$ and $1052.2{\mu}g/g$, respectively. In general, the antioxidant activity and the related parameters, including total phenolic content and vitamin C content decreased during fruit ripening. These results improve knowledge of the effect of ripening on the antioxidant activity and related compounds contents that could help to establish the optimum A. arguta fruit harvest data for various usages.

• Korean Journal of Plant Resources
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• v.26 no.2
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• pp.159-168
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• 2013

The study was conducted to determine the content of phenolics and flavonoids, antioxidant activity and antioxidant enzyme activity for the extract from 7 days old sprouts of cowpea (cv. "Seowon"), mungbean (cv. "Owool") and soybean (cv. "Pungsannamulkong"). Sprout length and weight of soybean sprouts were higher than those of cowpea and mungbean sprouts. Total phenolics content [mg ferulic acid equivalents (FAE) $kg^{-1}$ DW] was highest in soybean sprout extracts (82.2 mg $kg^{-1}$), followed by cowpea (32.2 mg $kg^{-1}$) and mungbean (24.5 mg $kg^{-1}$) sprout extracts (p < 0.05). The result of total flavonoid level [mg rutin equivalents $kg^{-1}$ DW] had same tendency to the total phenolics, showing lower amounts. The antioxidant activity of the methanol extracts from all the plant dose-dependently increased. DPPH (1,1-diphenyl-2-picryl hydrazyl radical) free radical scavenging activity was higher in cowpea (44%) and mungbean (42%) sprouts than in soybean sprouts (25%). Among antioxidant enzymes, APX and POX activities were highest in cowpea sprouts and CAT and SOD activities in soybean sprouts. The results showed that total phenolics content ($r^2$ = 0.5320 ~ 0.9032) and total flavonoids level ($r^2$ = 0.4672 ~ 0.9380) were highly correlated with antioxidant or with antioxidant enzyme activity, and that the level and activity of biologically active substances were different depending on plant species.

• Preventive Nutrition and Food Science
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• v.16 no.4
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• pp.370-375
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• 2011

The antioxidative activity and the polyphenolic composition were examined in four different cultivars of apple (Malus domestica), 'Fuji', 'Tsugaru', 'Hongro' and 'Kogetsu', and their parts (peel, core, pulp and juice). The total phenolics, flavonoids and anthocyanins differed among the tested cultivars and parts. Peel parts had the highest total phenolics and anthocyanin content. Contributions of those phenolics to total antioxidative activity were determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging assays, and the linoleic acid oxidation assay. Concentration of phenolics contributes significantly to the total antioxidative activity of apples. Clearly, apple peels, especially from Hongros and Kogetsus, possess high levels of phenolic compounds and antioxidants. Therefore, apple peels may potentially function as a value-added ingredient.

• Journal of Society of Preventive Korean Medicine
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• v.13 no.1
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• pp.59-67
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• 2009

Objectives : This research aimed to evaluate the effects of Rubus coreanus $M_{IQ}$. Methods: These extracts from fresh R. coreanus $M_{IQ}$. were investigated with radical scavenging activity, the content of total phenolics, ferric thiocyanate method and flavonoid contents Results: These results revealed that the ethyl acetate extract from fresh R. coreanus $M_{IQ}$. possesses remarkable radical scavenging activity. The content of total phenolics of the ethanol extract from dried R. coreanus $M_{IQ}$. ($IC_{50}$=155.87${\pm}$8.8${\mu}$g/mL) is the highest among all of the samples. The stronger radical-scavenging activity ($IC_{50}$=77.72${\pm}$2.1${\mu}$g/mL) of ethyl acetate extract from dried R. coreanus $M_{IQ}$. should be related to its phenolic content as measured by gallic acid test. Conclusion: These results suggest that dried R. coreanus $M_{IQ}$. may act as a potential antioxidant agent.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.310-316
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• 1994

The phenolic substances contents of 45 plant foods in Korean diet were determined by different methods. Total phenolics contents by Folin-Denis method were $0.1{\sim}5.8%$ (dry matter basis), in which persimmon leaf, chestnut's inner skin, Chinese quince, walnut, sunflower seed and arrowroot exhibited the higher levels above 2%. Condensed tannin contents by vanillin method were $0{\sim}48%$, in which Chinese quince and chestnut's inner layer gave very high levels. Protein-precipitable phenolic substances ranged from 0.4% to 2.2%, in which chestnut's inner layer, walnut and Chinese quince had the highest content. The ability of phenolics to form precipitate was higher with pepsin and albumin than with trypsin. Among different phenolics content, total phenlolics correlated significantly with protein-precipitable phenolics (r=0.65) and condensed tannin (r=0.56). Chinese quince, chestnut's inner skin and sorghum showed a relatively lower degree of polymerization, as expressed by vanillin/FolinDenis ratio. Processed foods from buckwheat, acorn, mugwort and arrowroot showed a lower content of phenolic substances, suggesting a negligible adverse effect on the bioavailability of food proteins, if any.