• Culinary science and hospitality research
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• v.17 no.1
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• pp.208-217
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• 2011

This study explores the antioxidant activity of solvent extracts from Vitis coignetiea skins, and the result is as follows. Total phenolic compound and flavonoids contents were the highest in ethyl acetate extract, $53.4{\pm}1.2\;mg$/100 g and $644.7{\pm}3.7\;mg$/100 g, respectively. Electron donating abilities of solvent extracts from Vitis coignetiea skin were proportionally increased with concentration and ethyl acetate extract ($80.93{\pm}0.58%$) showed the higher activity than BHT($63.21{\pm}0.72%$) at concentration of $50\;{\mu}l$/mL. Reducing power of solvent extracts from Vitis coignetiea skin was the highest in ethyl acetate extract(1.769) at concentration of $1,000\;{\mu}l$/mL. TBARS of ethyl acetate extract was higher than ascorbic acid. Nitrite scavenging ability of solvent extracts from Vitis coignetiea skin(pH 1.2, $1,000\;{\mu}l$/mL) was the highest in ethyl acetate extract($92.5{\pm}2.4%$).

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.5
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• pp.814-821
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• 2000

In order to investigate the possible use of omija extract as natural preservatives for nabak kimchi omija extract was tested for antioxidation and electron-donating ability and further more antimicrobial activites against lactic acid bacteria of nabak kimchi. The concentration of the test sample used were 0.5, 1.0, 1.5, 2.0%. Antioxidative activity measured the TBA value, when omija extract concentration % is higher the antioxidation effect were more evident with the increased omija extract concentrations, and showed a high electron donating activity more than 1.0%. As the result of isolated lactic acid bacteria from nabak kimchi the primary separation tool 117 strains, of these 4 strains which had excellent growth and a strong acid formation capability was selected the second time and Lactobacillus brevis, Lactococcus faecalis, Leuconostoc mesenteriodes, Lactobacillus palantarum were identified. After measuring the antimicrobial activity of the four lactid acid bacteris, except Lactobacillus brevis the other three bacteria showed strong antimicrobial activities. The results suggest the possible use of the omija extract as natural preservative for nabak kimchi.

• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.719-724
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• 2002

Fresh bamboo was charred in the mechanical steel kiln and traditional earth kiln, and then its smoke was condensed to produce bamboo smoke distillates (BSD). BSD made by mechanical steel kiln (MBSD) was purified by distillation. There is significant difference (p<0.05) in total phenol content among them, 663.40 ppm in MBSD, 571.62 ppm in PMBSD, and 485.16 ppm in TBSD. The nitrite scavenging activity and electron donation ability of BSDs were measured and the content of total phenol content was determined. The nitrite scavenging activity of BSD increased with increasing concentration of BSD at the same pH and decreased with increasing pH. There is significant difference (p<0.05) in nitrite scavenging activity among MBSD, purified MBSD (PMBSD), and BSD made by traditional earth kiln (TBSD) and the activity was the highest in MBSD and the lowest in TBSD. The electron donationg ability of BSDs increased with increasing the concentration of BSD and the reaction time. There is significant difference in the electron donation ability of BSDs at the same period and different concentration among the BSDs, the highest in MBSD and the lowest in TBSD.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.spc1
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• pp.209-214
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• 2006

One hundred Individuals that were collected from plains and mountains all around South Korea were used for this experiment. The inhibition abilities of lipid peroxidation by Artemisia spp. collections were compared with BHT (butylated hydroxytoluene). The results could be confirmed the excellency fur control of lipid peroxide level such as BHT 200 ppm in all mugwort collections. Antioxidant activity (AEAC), electron donating ability (EDA), total phenolic compound, and flavonoids of 100 Artemisia spp. collections were analyzed. Total phenolic compound contents of Artemisia spp. collections were ranged from 156 to 1,767 rng/100 g, and mugwort collections with more than 900 mg/100 g of total phenolic compound content were 20 individuals. Electron donating abilities were ranged from 13.4 to 95.0%, and mugwort collections over 90% of electron donating ability were 23 individuals. Antioxidant activity of ethanol extracts that used ABTS and DPPH radical were measured and mugwort collections with high total phenolic compound contents had high radical exclusion ability as well. Artemisia spp. collections, AC-60, AC-67, AC-77, that showed the high levels of antioxidant activities and had good growth characters and productivity, were selected for mass production.

• Culinary science and hospitality research
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• v.16 no.4
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• pp.297-304
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• 2010

This study examines the physicochemical property and antioxidant activity of wild grape juice, and the result is as follows. Total anthocyanin and color intensity contents of wild grape juice were $17.0{\pm}0.1%$ and $33.9{\pm}1.4%$, respectively. The contents of total phenols and flavonoid in wild grape juice were $25.4{\pm}3.1$ mg/100g, $4.4{\pm}1.4$ mg/100 g, respectively. Total mineral content in wild grape juice was $28.5{\pm}8.4$ mg/l00 g and the potassium content($11.3{\pm}0.3$ mg/100 g) was the highest Electron donating abilities of wild grape juice at concentration of $1,000\;{\mu}L$/mL were $94.8{\pm}1.2%$ Reducing power of wild grape juice at concentration of $1,000\;{\mu}L$/mL was 1.134. The electron donating abilities and reducing power were increased significantly with the sample concentration in the reaction mixture increased The nitrite scavenging ability was dependent on pH of the reaction mixture and sample concentration. The nitrite scavenging ability of wild grape juice was $77.1{\pm}1.1%$ at concentration of $1,000\;{\mu}L$/mL under pH 1.2.

• Parasites, Hosts and Diseases
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• v.60 no.6
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• pp.401-407
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• 2022

Antimalarial drugs play an important role in the control and treatment of malaria, a deadly disease caused by the protozoan parasite Plasmodium spp. The development of novel antimalarial agents effective against drug-resistant malarial parasites is urgently needed. The novel derivatives, SKM13-MeO and SKM13-F, were designed based on an SKM13 template by replacing the phenyl group with electron-donating (-OMe) or electron-withdrawing groups (-F), respectively, to reverse the electron density. A colorimetric assay was used to quantify cytotoxicity, and in vitro inhibition assays were performed on 3 different blood stages (ring, trophozoite, and schizonts) of P. falciparum 3D7 and the ring/mixed stage of D6 strain after synchronization. The in vitro cytotoxicity analysis showed that 2 new SKM13 derivatives reduced the cytotoxicity of the SKM13 template. SKM13 maintained the IC₅₀ at the ring and trophozoite stages but not at the schizont stage. The IC₅₀ values for both the trophozoite stage of P. falciparum 3D7 and ring/mixed stages of D6 demonstrated that 2 SKM13 derivatives had decreased antimalarial efficacy, particularly for the SKM13-F derivative. SKM13 may be comparably effective in ring and trophozoite, and electron-donating groups (-OMe) may be better maintain the antimalarial activity than electron-withdrawing groups (-F) in SKM13 modification.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.2
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• pp.250-256
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• 2013

We investigated noodles supplemented with turmeric, purple sweet potato, or seaweed (Hizikia fusiforme) for their functional properties, including total phenol, flavonoid contents, electron donating abilities, and nitrite scavenging abilities. The percentage of total phenolic compounds in turmeric, purple sweet potato, and seaweed noodles were 2.40, 2.47, and 1.27%, respectively, whereas the percentage of total flavonoid contents were 0.55, 0.92, 0.74%, respectively. Results showed that purple sweet potato noodles had the highest amount of phenolic compounds and flavonoids compared to the other types of noodles. The electron donating abilities of the turmeric, purple sweet potato, and seaweed noodles were 4.72, 4.11, and 3.11 at 1,000 ppm respectively. The nitrite scavenging abilities of the turmeric, purple sweet potato, and seaweed noodles were 75.93, 79.81, and 73.51% at pH 1.2, respectively. Purple sweet potato noodles had the highest nitrite scavenging abilities, with an effect better than BHT and ascorbic acid. The ferrous ion chelating effect of turmeric, purple sweet potato, and seaweed noodles were 12.17, 13.63, and 42.12%. All of the experimental results showed good anti-oxidative activity; thus rice noodles supplemented with turmeric, purple sweet potato, or seaweed, have good functional effects for human beings.

• The Korean Journal of Community Living Science
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• v.16 no.2
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• pp.17-26
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• 2005

This study was conducted to investigate the usefulness of a hot water extract of licorice root as a source for production of healthy food. The electron donating capacity of the hot water extract of licorice root was very strong. This activity decreased by $6.9\%$ after keeping it in 5 days of cold storage, but it was not significantly different. Ten types of licorice jellies were prepared, using agar, agar-pectin, agar-cellulose, 2 different proportions of agar-pectin-cellulose as a gelling agent, and 2 levels of sugar. Among the 5 jellies containing $10\%$ sugar, the elasticity and overall acceptance of the agar jelly obtained the highest sensory score, but the color and flavor were not affected by the type of gelling agents. As the sugar concentration increased to $15\%$, the elasticity of the agar jelly was also evaluated as being the best one among the 5 jellies, but the overall acceptance was not significantly different from the others.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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• pp.1039-1043
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• 1997

Correlation among color intensity, electron donating ability to $\alpha$, $\alpha$-diphenyl-$\beta$-dicrylhydrazy(DPPH) and cultivation conditions by Bacillus subtilis DC-2 were tested with response surface methodology. Both of pigment generation ability and DPPH were more affected by temperature than any other factor. The highest correlation was appeared between color intensity and DPPH as 0.8364 which is significant at 1% level. After fixing cultivation time which is not significant at 10% level to 84hrs as optical cultivation time, response surface methodology was conducted in regarding temperature and color intensity. As a result of overlapped contour map of color intensity and DPPH, when cultivation temperature was in the range of 38.9~41.1$^{\circ}C$ and pH was in the range of 8.34~9.12, optical density of color intensity was predicted higher than 0.374 at 390nm and DPPH was infered higher than 1.310 at 528nm. In the range of optical culture condition, cultivation temperature, pH and cultivation time was fixed to 4$0^{\circ}C$, 8.5 and 85hrs, respectively. In resulting, observation value of color intensity and DPPH was in the range of anticipation value as 0.386 at 390nm and 1.332 at 528nm respectively.

• The Korean Journal of Food And Nutrition
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• v.21 no.3
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• pp.312-319
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• 2008

The principal objective of was to assess the effects of herb extracts on the antioxidant activity and quality characteristics of Maejakgwa. The total phenolic and flavonoid contents were found to be the highest by a significant degree in the rosemary, lavender, thyme, lemon balm and olive samples, in order. With regard to electron donating ability, increasing concentrations of added herbs resulted in a more significant rise in the DPPH radical scavenging effect in a range of concentrations of between $100{\sim}1000{\mu}g/m{\ell}$. In particular, the rosemary, lavender, and thyme samples were shown to be lower in antioxidant activity than ascorbic acid, but higher than a-tocopherol, thus the antioxidant activities detected in the rosemary, lavender, and thyme samples were considered to be excellent. With regard to reducing ability, increases in the concentration of added herb extract resulted in significant growth. However, the anti-oxidative activity detected in the rosemary extract was indicated to be superior even to that of $\alpha$-tocopherol when added to concentrations of $500{\sim}1,000{\mu}g/m{\ell}$. In our assessment of external appearance, color, flavor, texture, and overall quality, the highest preference was seen in the control group and in the group with 2% added rosemary extract. The lowest score was earned in the group with a 5% addition of rosemary. The functional ingredients and antioxidant activities of the samples were excellent. Our results appear to indicate that rosemary has some value as a natural antioxidant that can prevent oxidation in food.