• KSBB Journal
• /
• v.29 no.6
• /
• pp.421-425
• /
• 2014

In this study, the antioxidant activities of fractions (methanol, hexane, methylene chloride, butanol, ethyl acetate and water) of Solanum nigrum L. extract was investigated. The contents of total phenolic compounds of each fractions of methanol, butanol, methylene chloride, ethyl acetate, hexane and water are $4.41{\pm}0.23%$, $5.57{\pm}0.35%$, $9.89{\pm}0.19%$, $9.86{\pm}0.19%$, $1.89{\pm}0.04%$, and $3.18{\pm}0.06%$, respectively. For assay of antioxidant activity, 1,1-diphenyl-2-picryhydrazyl (DPPH) radical scavenging activity, reducing power and nitrite scavenging activity are evaluated. In DPPH radical scavenging activity, the highest effect was obtained from the fraction of ethyl acetate. Reducing power is ordered as ethyl acetate > methylene chloride > methanol. In nitrite scavenging activity, the highest activity was 5.5% (butanol fraction), whereas hexane fraction did not detected. Overall, antioxidant activities are closely related the content of phenolic compound in extracts of S. nigrum L.

• The Korean Journal of Food And Nutrition
• /
• v.26 no.2
• /
• pp.280-286
• /
• 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 the Korean Society of Food Science and Nutrition
• /
• v.35 no.6
• /
• pp.774-779
• /
• 2006

The commercial green tea leaves were packaged with polyethylene film and irradiated by electron beam at doses of 0, 5, 10, 20, and 30 kGy. After irradiation, green teas were prepared by soaking the leaves in water (1 g/100 mL) at $75^{\circ}C$ for 10 min, and the physicochemical characteristics of green tea were determined. Electron beam irradiation decreased total phenol contents (TPC), total flavanol contents (TFC), ascorbic acid contents (AAC). Irradiation at dose of 20 kGy decreased TPC, TFC, and AAC from 223.46, 32.50, and 6.03 mg/g to 202.88, 31.16, and 5.57 mg/g, respectively, compared with non irradiated control. Electron beam irradiation also decreased catechins, caffeine, and nitrite scavenging activity of green tea. However, the changes of overall color and radical scavenging activity of irradiated green tea were negligible.

• Korean journal of food and cookery science
• /
• v.23 no.2 s.98
• /
• pp.165-172
• /
• 2007

This study was conducted to investigate the antioxidant amounts and properties of barley leaf tea and green tea at under various leaching conditions. The leaching temperatures and times of the distilled water were 50, 70 and $90^{\circ}$C for 1, 3 and 5 min, respectively. The levels of crude fat and ash in the barley leaf tea were higher than those in green tea. Brown color intensity and flavonoid absorbance increased with leaching temperature. The highest vitamin C levels and water-soluble phenol resulted at $90^{\circ}$C for 3 min. The DPPH radical scavenging activities of the barley leaf tea and of green tea were 11.06 and 50.56%, respectively, compared to 2.9% for L-ascorbic acid (150 ppm). The nitrite scavenging activities of barley leaf tea and green tea were 95.11 and 74.88%, respectively. The SOD-like activities of barley leaf tea, green tea, and L-ascorbic acid (150 ppm) were 12.99, 8.33, and 12.75%, respectively. The antioxidant effect of green tea was higher than that of barley leaf tea and lastly, the SOD-like activity of barley leaf tea was as high as that of green tea.

• The Korean Journal of Food And Nutrition
• /
• v.20 no.2
• /
• pp.114-119
• /
• 2007

Our research objective was to examine the in vitro biological activity of deer antler(Nogyong in Korean) extract, including the antioxidative, nitrite scavenging, and tyrosinase inhibitory effects, as well as the antithrombotic, and angiotensin I converting enzyme(ACE) inhibitory activities. The carbohydrate, protein, fat, and mineral contents of the deer antler were 7.6%, 65.3%, 3.2% and 23.9%, respectively. The electron donating ability(EDA) by the reduction of 2,2'-diphenyl-1-picrylhydrazyl(DPPH) was 67.1%, and the inhibition rate of lipid peroxidation by the thiocyanate method using linoleic acid was 92.1% in 100 mg/ml of extract. The nitrite scavenging effects were pH dependent, and were highest at pH 1.2 and lowest at pH 6.0. The sample inhibition rate against tyrosinase was above 64.0%. The platelet aggregation induced by ADP(adenosine-5'diphosphate) was inhibited up to 51.7%, and the inhibitory effect was dependent on the sample concentration. Lastly, the inhibition rate of ACE was 47.5% in 100 mg/ml of deer antler extract.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.34 no.7
• /
• pp.942-947
• /
• 2005

This study was investigated to analyze the effect of extracts from the Lepista nuda, on the antioxidant activity to form a part of studies on the functional materials of L. nuda. Antioxidant activity of L. nuda extracts was evaluated by measuring the electron-donating ability (EDA), the superoxide dismutase (SOD)-like activity, and the nitrite-scavenging ability. The EDAs of water and ethanol extracts at the concentration of 1,000 ppm by the rotary heating method from L. nuda were $60.47\%$ and $60.13\%$, respectively and those of water and ethanol extracts by microwave-assisted method were $87.73\%$ and $84.84\%$, respectively. The measurements of SOD-like activity were in the range of $24.58\%\~42.03\%$ at 1,000 ppm. EDA and SOD were increased with the concentrations of extracts. The nitrite-scavenging ability at the concentration of 1,000 ppm was the highest and $29.77\%$ at pH 1.2, and was decreased with an increment of pH value. These results indicated that microwave­assisted water extract from L. nuda showed the highest activities on the EDA and nitrate-scavenging ability, while the rotary heating ethanol extract had the highest effect on the SOD-like activity.

• Food Science and Preservation
• /
• v.13 no.5
• /
• pp.548-554
• /
• 2006

This study investigated the effect of the addition of germinated brown rice extract powder (0, 0.67, 3.35 and 6.70%) to the fermentation of Korean cabbage kimchi. During the fermentation of Korean cabbage kimchi with GBREP, content of total free amino acid and essential amino acid was showed higher value by increasing the addition of GBREP. In particular, ${\gamma}$-aminobutyric acid (GABA) content of Korean cabbage kimchi, prepared with 6.70% GBREP was 2 times higher than control Korean cabbage kimchi. By increasing the content of GBREP, total phenol content was showed high value and the content was more increased during fermentation except control Korean cabbage kimchi. By increasing the content of GBREP, electron donating activity and superoxide radical scavening activity were showed higher value and then showed maximum scavening activity on palatable period. Nitrite-scavenging ability of Korean cabbage kimchi with GBREP was higher than control Korean cabbage kimchi and showed the highest scavenging ability at pH 1.2.

• Food Science and Preservation
• /
• v.8 no.4
• /
• pp.399-404
• /
• 2001

Antimutagenic, antioxidative and nitrite-scavenging effects of seafood bun were investigated. Each samples were extracted with methanol. Aflatoxin Bl(AFB1) was used as mutagen. Seafood bun added 20% kimchi(5mg/plate) reduced mutagenicity of AFB1 for Salmonella typhimurium TA and YG 1024 to 47% and 61%, rrespectivery. The reduction rate of seafood bun added 20% kimchi was higher relative to that of other samples. Mydrogen donating activity in all buns showed over 50% and seafood bun added 20% kimchi was higher than others, but the activity was lower than that of 0.1% BHT. The peroxide value for linoleic acid increased during the storage, the values in seafood bun added 20% kimchi was higher than others, but the activity was lower than that of 0.1% BHT. The peroxide value for linoleic acid increased during the storage, the values in seafood bun added 20% kimchi was significantly lower and the values in other buns were a lower than that of control, the values in all of the samples were higher than that in 0.1% BHT. Among the samples tested, the TBA value in the seafood bun added 20% kimchi for liver homogenate of rat was the lowest. Nitrite-scavenging effect in all the samples tested was higher than 50%.

• Korean Journal of Plant Resources
• /
• v.25 no.1
• /
• pp.80-88
• /
• 2012

This study was conducted to clarify the antimicrobial effects and radical scavenging activities of the cosmetic compositions having the natural plant pigments, and to enhance the natural materials utilization of cosmetics. The antimicrobial activities of the fifteen kinds of cosmetic composition having natural plant pigments were evaluated using the agar diffusion method. Most of the cosmetic composition having the natural pigments showed the clear zone formation of growth inhibition against Bacillus subtilis, Staphylococcus aureus, Listeria monocytogenes, Vibrio parahaemolyticus and Aspergillus flavus. Especially, purple sweet potato, bitter melon, mulberry leaf and gromwell showed the higher antimicrobial activities. All the cosmetic compositions were evaluated for their antioxidant activity using DPPH radical scavenging capacity and nitrite scavenging ability activity. Both of the free radical DPPH and nitrite scavenging ability was the highest in the cosmetic compositions of onion peel, and these antioxidant activity was significant differences according to different plant pigments. In this study, we conjectured that the plant pigment had the potent biological activities, therefore these plant resources having functional components could be a good materials for development into source of natural cosmetics.

• Bulletin of the Korean Chemical Society
• /
• v.22 no.4
• /
• pp.362-366
• /
• 2001

To show the effects of metallothionein (MT) on the activity of enzymes involved in the removal of reactive oxygen species, MT has been added to the assay systems of superoxide dismutase (SOD), catalase and peroxidase. We have used assay systems of SOD based on NADPH oxidation and nitrite formation from hydroxylammonium chloride as an assay of superoxide breakdown rate. The two assay systems showed different results at the high concentration of MT. MT showed the scavenging of superoxide in the SOD assay system in the presence and absence of SOD. MT added to the SOD assay system behaved as an activator of SOD, but apo-MT behaved as an inhibitor. When MT was added to the assay system in the presence of a fixed amount of SOD, the breakdown rate of superoxide increased. The effects of MT on the decomposition of hydrogen peroxide and the activity of catalase and peroxidase decomposing hydrogen peroxide were evaluated. MT decreased the activities of catalase and peroxidase. We have concluded that the function of MT as an antioxidant might effect the level of superoxide scavenging and not the level of hydrogen peroxide.