• Journal of Physiology & Pathology in Korean Medicine
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• v.25 no.1
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• pp.92-99
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• 2011

Topical natural antioxidants are a useful strategy for the prevention of oxidative stress mediated cardiovascular disease including atherosclerosis. From the viewpoint of this underlying principle, the screening of natural plant extracts with scavenging activity for pro-oxidant reactive species is a primary requirement for the development of new topical antioxidant formulations. Euryale ferox Salisbury (EF) is botanical name and it's pharmaceutical name is EURYALES SEMEN (ES). The stems and branchs of EF have been used as a traditional herbal medicine for the treatment of dysentery, diarrhea, leucorrhoea, incontinence and paralysis of joint. In this study, the antioxidant activity of extract from EF was studied in vitro methods by measuring the antioxidant activity and free radical scavenging activity by TEAC and DPPH, measuring the scavenging effects on reactive oxygen species (ROS) [superoxide anion, hydroxyl radical] and on reactive nitrogen species (RNS) [nitric oxide and peroxynitrite] as well as measuring the inhibitory effect on $Cu^{2+}$-induced human LDL oxidation. The EF extracts were found to have a potent scavenging activity, as well as an inhibitory effect on LDL oxidation. In conclusion, the EF extracts have antioxidative effects in vitro system, which can be used for developing pharmaceutical drug against oxidative stress and chronic degenerative disease such as atherosclerosis.

• Food Science and Preservation
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• v.9 no.4
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• pp.385-390
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• 2002

Functional activities of Lyophyllum ulmarium microwave-assisted extracts under different conditions including electron donating ability, tyrosinase inhibition activity and nitrite scavenging effect were examined. Total polyphenol content increased as increasing microwave power up to 90 W in the water extracts. Electron donating ability increased with microwave power up to 90 W in 50% ethanol extract and 99% ethanol extract. Tyrosinase inhibition activity and nitrite scavenging effect in the extract increased as microwave power increased during extraction. Total polyphenol content increased as extending extraction time up to 5 min in the water extract. But the highest electron donating ability and tyrosinase inhibition activity was obtained after 10 min extraction. Significantly higher total polyphenol content and electron donating ability were found in the water extract whereas greater tyrosinase inhibition activity and nitrite scavenging effect were observed in 99% ethanol extract. The maxium nitrite scavenging effect was found at pH 1.2 and decreased as pH increased.

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.1013-1017
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• 2002

Functional activities of Flammulina velutipes extract including electron donating ability, nitrite-scavenging effect, and tyrosinase inhibition activity was examined. Extraction were carried out by microwave-assisted extraction (MAE) under different conditions including solvent and microwave power. Tyrosinase inhibition activity and nitrite-scavenging effect increased as microwave power increased during extraction. Total phenol content and electron-donating ability reached maximum at the microwave power of 90 W. Total polyphenol content and electron-donating ability increased as extraction time extended up to 15 min, with the highest tyrosinase inhibition obtained after 5 min extraction. Significantly higher tyrosinase inhibition activity was found in 99% ethanol extract, whereas greater nitrite-scavenging effect was observed in the water extract. The maximum nitrite-scavenging effect was found at pH 1.2 and decreased as pH increased.

• Food Science and Biotechnology
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• v.17 no.2
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• pp.295-301
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• 2008

In this study, the antioxidant activities of red pepper seed kimchi extracts were examined. The extracts were evaluated by various antioxidant assays that included determinations of total phenolic and flavonoid contents, DPPH radical scavenging, superoxide anion radical scavenging, nitric oxide scavenging, superoxide dismutase (SOD) activity, metal chelating activity, and reducing power. All the kimchi extracts showed strong antioxidant activities by the tested methods. The 7% red pepper seed kimchi that was fermented for 6 days possessed the highest activity according to the performed tests. Yet, the highest scavenging activity was exhibited against nitrite, by extracts from kimchi for 0 day of fermentation rather than 6 days. All the activities for the kimchi fermented for 0 day with the addition of 7% red pepper seed increased markedly with an increase in concentration. With the exception of metal chelating and SOD activities, for the antioxidant properties assayed, the red pepper seed kimchi extracts were found to be highly effective.

• Bulletin of the Korean Chemical Society
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• v.33 no.3
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• pp.958-962
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• 2012

In single-molecule fluorescence experiment, the oxygen scavenging system is indispensable for avoiding photo-bleaching of fluorescent dyes. Here we report that the gloxy-based oxygen scavenging system commonly used in single molecule fluorescence experiments can disturb the solution pH considerably. To track in situ pH change, we utilized the pH-sensitive conformational transition of i-motif and examined the transition with ensemble and single-molecule FRET measurements. Based on our results, we also suggested several practical remedies for the stability of the solution pH.

• Korean Journal of Pharmacognosy
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• v.34 no.4 s.135
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• pp.324-326
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• 2003

The methanol (MeOH) extract and ist fractions of Taraxacum mongolicum (Compositae) were examined for their scavenging effects on 1,1-diphenyl-2- phenylhydrazyl (DPPH) and superoxide radicals, and hepatoprotective effects on tacrine-induced cytotoxicity in human hepatoma cell line, Hep G2 cells. Both methylene chloride $(CH_2Cl_2)$ and butanol (n-BuOH) soluble fractions of the MeOH extract showed the free radicals scavenging and hepatoprotective effects. From these results, it is suggested that hepatoprotective effect of these fractions partly relies on their free radical scavenging activity.

• ALGAE
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• v.18 no.4
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• pp.341-347
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• 2003

The potential antioxidative activity of water-soluble enzymatic hydrolyzates from a kelp, Ecklonia cava was evaluated by free radical scavenging and lipid peroxidation assays. To prepare water-soluble hydrolyzates from E. cava the seaweed was enzymatically hydrolyzed by five carbohydrases (Viscozyme, Celluclast, AMG, Termamyl and Ultraflo) and five proteases (Protamex, Kojizyme, Neutrase, Flavourzyme and Alcalase). Among all the hydrolyzates, Celluclast hydrolyzate effectively scavenged free radicals released from DPPH (1,1-diphenyl-2- pricrylhydrazyl) and recorded around 73% scavenging activity at the concentration of 4 mg ${\cdot}ml^{-1}$. This hydrolyzate was thermally stable and DPPH radical scavenging activity remained 80% or higher at heating temperatures of 40 and 60$^{\circ}C$ up to 12 h and around 80% at 100$^{\circ}C$ up to 8 h. AMG and Ultraflo hydrolyzate inhibited the lipid peroxidation of fish oil as that of $\alpha$-tocopherol. These results suggested that an enzymatic extraction will be an effective way for the production of a potential antioxidant from seaweeds.

• Journal of Applied Biological Chemistry
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• v.54 no.3
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• pp.184-189
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• 2011

Polysaccharide (PS) was fractionated from hot-water extract of Artemisia iwayomogi Kitamura stems. PS showed considerably higher hydroxyl radical scavenging activity than caffeic acid and glutathione. PS showed lower superoxide anion radical scavenging activity than hydroquinone and ascorbic acid. The scavenging activity of PS on the reactive oxygen species (ROS) induced by human neutrophils with zymosan was determined by the lucigenin-enhanced chemiluminescence assay. The scavenging effect of the PS on ROS as determined by the chemiluminescence assay was about 2-fold stronger than that of ascorbic acid at the same concentration. PS significantly decreased protein carbonyl and malonaldehyde contents in UVB irradiated skin homogenates, which was comparable to glutathione at the same concentration. This result suggested that PS derived from A. iwayomogi Kitamura stems may be a potent candidate as functional compound for the protection on UVB induced skin damage in cosmetics.

• Natural Product Sciences
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• v.23 no.2
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• pp.75-83
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• 2017

The optimization and microwave assisted extraction of stem bark of Terminalia arjuna, quantitative estimation of the marker compounds arjunic acid and arjunolic acid using HPTLC and the evaluation of free radical scavenging activity has been performed in this study. The central composite design was used for optimization and the values of parameters for optimized batch of microwave assisted extraction were 1000 W (Power), 3 minutes (Time) and 1/120 (Solid/solvent ratio). The solvent system to carry out the HPTLC was toluene: acetic acid: ethyl acetate (5: 5: 0.5) and quantitative estimation was done using standard equations obtained from the marker compounds. The in-vitro free radical scavenging activity was performed spectrophotometrically using ascorbic acid as standard. The value of estimated percentage yield of arjunic acid and arjunolic acid was 1.42% and 1.52% which upon experimentation was obtained as 1.38% and 1.51% respectively. The DPPH assay of the different batches of microwave assisted extraction and marker compounds taken suggested that the marker compounds arjunic acid and the arjunolic acid were responsible for the free radical scavenging activity as the batch having the maximum percentage yield of the marker compounds showed best free radical scavenging effect as compared to standard ascorbic acid. The $IC_{50}$ value of the optimized batch was found to be 24.72 while that of the standard ascorbic acid was 29.83. Hence, the yield of arjunic acid and arjunolic acid has direct correlation with the free radical scavenging activity of stem bark extract of Terminalia arjuna and have potential to serve as active lead compounds for free radical scavenging activity.

• Journal of Nutrition and Health
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• v.38 no.5
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• pp.386-394
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• 2005

Effects of root, stem and leaf extract of sancho (Zanthoxylum schinifolium) on the inhibition of lipid peroxidation in the hepatic microsome of rat, DPPH radical scavenging activity and activated partial thromboplastin times (APTT) were examined in vitro. The highest inhibition of hepatic microsomal lipid peroxidation was observed by ethyl acetate fraction than that of methylene chloride fraction of the root and stem extracts. The high inhibition of lipid peroxidation was determined in the leaf, the root and the stem in order. The DPPH radical scavenging activity of ethyl acetate fraction was higher than that of n-butanol fraction and it was similar to the root and the steam extract. It was similar to the inhibition of hepatic microsomal lipid peroxidation. The DPPH radical scavenging activity was the highest in 2.500mg/mL of ethyl acetate fraction and it was 4.4 fold higher than that of $\alpha-tocopherol$, as an antioxidant standard. The DPPH radical scavenging activity was dependent on the extract concentration in the range of 0.125-5.000 mg/mL. The throm-boplastin times were higher than that of n-butanol fraction and it was similar to the root and the steam extracts. The leaf extract showed the highest antithrombogenic effect followed by the stem and then the root extract. The activated partial thromboplastin times were ependent on the extract concentration in the range of 0.100-2.000 mg/mL. Consequently, the effects of antioxidative, DPPH radical scavenging activity and antithrombogenic of Z. schinifolium was observed due to the inhibition of lipid peroxidation and the DPPH radical scavenging activity by methylene chloride, n-butanol and ethyl acetate fraction of the leaf extract. (Korean J Nutrition 38(5): 386 - 394, 2005)