• Journal of the Korean Society of Food Culture
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• v.32 no.5
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• pp.446-452
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• 2017

This study was conducted to evaluate the quality characteristics and antioxidant activities of salad dressing prepared with acaiberry powder (0, 1, 3, and 5%). The pH and titratable acidity increased as the acaiberry powder increased. The sugar content showed no significant differences between samples. The viscosity was lowest in the controls and increased with increasing amounts of the acaiberry powder. The lightness and yellowness values decreased, while the redness values increased with increasing amounts of acaiberry powder. The total polyphenol content ranged from 10.26-45.19 mg GAE/100 g, increasing with increased acaiberry powder levels. The antioxidant activities measured via DPPH radical scavenging activity, reducing power and FRAP also increased with increasing acaiberry powder concentrations. Finally, a consumer acceptance test revealed that up to 3% acaiberry powder could be added to salad dressing to provide high antioxidant activity without sacrificing sensory quality.

• Food Science and Biotechnology
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• v.18 no.6
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• pp.1532-1536
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• 2009

The objective of this study was to evaluate the antioxidant effects and acetylcholinesterase (AChE) inhibition activity of mulberry fruit extracts prepared by hot water (MFH) and 80% ethanol (MFE). Total polyphenolic contents of MFH and MFE were $195{\pm}3.4\;mg$ gallic acid equivalents/g MFH and $185{\pm}2.8\;mg$ gallic acid equivalents/g MFE. MFH and MFE significantly quenched 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydrogen peroxide dose-dependently, and showed high chelating ability and reducing power in non-cellular systems. MFH and MFE also inhibited the formation of intracellular reactive oxygen species and lipid peroxidation, and elevated intracellular glutathione (GSH) levels in RAW264.7 cells. In addition, MFH and MFE also dose-dependently suppressed AChE activity.

• Food Science and Biotechnology
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• v.18 no.6
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• pp.1523-1527
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• 2009

The present study was to investigate the in vitro antioxidant potential of hot water extract and its fractions from dichloromethane ($CH_2Cl_2$), ethyl acetate (EtOAc), n-butanol (n-BuOH), and water ($H_2O$) of castor-aralia (Kalopanax pictus) leaves using different antioxidant tests. Among these crude extract and fractions, EtOAc fraction exhibited higher antioxidant potency than others in 1,1-diphenyl-2-pricylhydrazyl (DPPH) free radical scavenging, reducing power assay, and reactive oxygen species (ROS) scavenging activity. However, $CH_2Cl_2$ fraction showed higher hydroxyl radical scavenging and DNA damage protective activity. This work demonstrates the potential of castor-aralia leaves as antioxidant functional food ingredients.

• The Korean Journal of Food And Nutrition
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• v.36 no.6
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• pp.471-478
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• 2023

This study investigated the quality characteristics and antioxidant activities of salad dressing prepared with Jerusalem artichoke powder (0%, 4%, 8%, and 12%). The pH, soluble solid content, and viscosity increased as the content of Jerusalem artichoke powder increased. The titratable acidity showed no significant differences between samples. The lightness values decreased, while the redness and yellowness values increased with increasing amounts of Jerusalem artichoke powder. The total polyphenol content ranged from 52.00-69.64 ㎍ GAE/g, and increased with the increase in Jerusalem artichoke powder levels. The antioxidant activities measured via DPPH and ABTS radical scavenging activity and reducing power also increased with increasing Jerusalem artichoke powder, at a higher rate than in the control. These results suggest that it is beneficial to add Jerusalem artichoke powder when in salad dressing.

• KSBB Journal
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• v.30 no.6
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• pp.302-306
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• 2015

In this work, the antioxidant activity and total phenolic compound content of 6 fractions of Smallanthus sonchifolius, Agrimonia pilosa, and Lithospermum erythrorhizon extract were investigated. The highest total phenolic compound contents of each plant extracts were obtained from n-butanol ($13.75{\pm}0.21%$) and methylene chloride ($12.89{\pm}1.10%$) fractions (S. sonchifolius), ethyl acetate ($19.69{\pm}1.02%$) and water ($18.72{\pm}0.76%$) fractions (A. pilosa), and n-butanol ($36.26{\pm}1.26%$) and ethyl acetate ($17.66{\pm}0.94%$) fractions (L. erythrorhizon), respectively. As a result of DPPH radical scavenging activity in 10 mg/mL condition, the highest activity were obtained from n-butanol fraction of S. sonchifolius (81.06%), ethyl acetate fraction of A. pilosa (86.32%), and n-butanol fraction of L. erythrorhizon (82.6%), respectively. Also, the highest reducing power was obtained same fractions as well as DPPH adical scavenging activity. Overall, antioxidant activity has relatively closely connected with contents of total phenolic compounds in S. sonchifolius and L. erythrorhizon extracts.

• Korean journal of food and cookery science
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• v.25 no.2
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• pp.219-226
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• 2009

Red ginseng extract was added to Yanggaeng to determine a practical use for the herb which has medical usage and functionality. We examined the antioxidant activity and quality characteristics of Yanggaeng prepared with different amounts (as ratios of 1%, 2%, 3% to the total materials) of red ginseng extract, as well as those of commercial red ginseng Yanggaeng. The antioxidant activity of the Yanggaengs samples was estimated by the DPPH free radical scavenging activity, $ABTS^{+\cdot}$ scavenging activity, and reducing power. The antioxidant activity of the Yanggaeng increased as a result of the addition of the red ginseng extract. Levels of polyphenol compounds and flavonoids increased according to the extract concentration. The quality characteristics of the red ginseng Yanggaeng were estimated in terms of pH, sugar content, viscosity, color, texture profile analysis, and sensory evaluations. With increasing concentrations of the extract, viscosity and sugar content increased, but pH decreased. In terms of the overall palatability, color, taste, flavor, and hardness, the 3% red ginseng Yanggaeng was determined as the best among the tested samples. Also, the 3% red ginseng Yanggaeng had higher scores than the commercial red ginseng Yanggaeng.

• Preventive Nutrition and Food Science
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• v.16 no.2
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• pp.179-183
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• 2011

This study was conducted to determine the biological activities of 70% ethanol extracts from rice husks of nine rice cultivars in Korea. The relative antioxidant activities of rice husk extracts were evaluated by determining DPPH, ABTS radical scavenging activity and reducing power. The contents of total polyphenol, flavonoid and r-oryzanol were measured by spectrophotometric methods. Among the extracts of rice husks, Nokmi rice husks tended to have the most effective antioxidant activities compared to other rice husk varieties. Seolgaeng rice husk extract showed anti-proliferative activity against cancer cell lines (MCF7 and NCI-H460), and Hongjinju rice husk extract significantly exhibited mitogenic activity.

• Journal of Microbiology and Biotechnology
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• v.8 no.6
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• pp.700-704
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• 1998

Each of the recombinant structural genes of Helicobacter pylori urease, ureA and ureB, was cloned and overexpressed as inclusion bodies. Solubilization and renaturation of the inclusion bodies were carried out, to accelerate the pairing of sulfhydryl groups and the incorporation of nickel ions, which would lead to the native structure with high enzyme activity. Rates of urea hydrolysis were monitored as an indication of in vitro activation of renatured ureases. The activation of the apoprotein using 1 mM nickel ion, 100 mM sodium bicarbonate and a 10:1 ratio of reducing power resulted in a weak urease activity (about 11% of the native urease activity encoded by pTZ 19R/ure-l). When a sparse matrix screen method originally discovered for the crystallization of proteins was used, the activity increased higher than that obtained using glutathione. The effect of polyethylene glycol (PEG) on the activity was noticeable, giving two-fold increase in the specific activity (about 11 U/mg of protein corresponding to 22% of the native urease activity encoded by pTZ19R/ure-1).

• Journal of the Korean Society of Food Culture
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• v.36 no.5
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• pp.522-529
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• 2021

This study was conducted to analyze the antioxidant and antidiabetic activities of acorns according to the types of Quercus serrata Thunb (QST) and Q. acutissima Carruther (QAC). The total polyphenol contents of the extracts from QST and QAC were 220.59 and 320.96 mg GAE/g, respectively. The content of total polyphenol of QAC was higher than that of QAC (p<0.001). DPPH (2,2 Diphenyl 1 picrylhydrazyl) radical scavenging activity, reducing power and superoxide dismutase (SOD)-like activity were increased in a concentration-dependent manner by both acorn extracts, and QAC showed high activity in all antioxidant experiments (p<0.05). The inhibitory activities of α-glucosidase and α-amylase were also increased in a concentration-dependent manner, and QAC showed higher inhibitory activity than QST (p<0.05). Our study indicates that QST and QAC are functional food materials with high antioxidant and antidiabetic activities. In addition, QAC has a higher physiological activity than QST.

• The Korean Journal of Food And Nutrition
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• v.35 no.4
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• pp.268-275
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• 2022

The purpose of this study was to confirm the possibility of using Korean purple yam (Dioscorea alata) as proximate composition, material, and antioxidant activity. In the proximate composition of the freeze-dried purple yam powder, the carbohydrate content was the highest at 86.67%, and in minerals, potassium showed the highest content at 1,765.69 mg/100 g. To study the antioxidant activity of purple yam, distilled water and 70% ethanol were used as extraction solvents. The total polyphenol, total flavonoid, and total anthocyanin contents were 1.3~1.6 times higher in 70% ethanol extract, than in the distilled water extract. As a result of ORAC, DPPH and ABTS radical scavenging activity, SOD activity, and reducing power, the 70% ethanol extract showed higher antioxidant activity than the distilled water extract in all results. As a result of freeze-drying purple yam and measuring antioxidant activity by extraction solvents, it is concluded that purple yam can contribute to the food industry as a natural antioxidant and health functional material.