• Bulletin of the Korean Chemical Society
• /
• 제31권9호
• /
• pp.2557-2560
• /
• 2010

To assay for antioxidant capacity of natural products considered important in producing human health benefits, a practical and economical method using pellet techniques was developed. A standard visualizing reagent, 1,1diphenyl-2-picryl-hydrazyl (DPPH), was mixed with a water-miscible polyvinyl alcohol (PVA), serving as a solid phase support for the DPPH reagent. A DPPH pellet was prepared by dropping a small volume of the DPPH solution onto PET film, and drying in an oven. The PVA-based DPPH pellet was dissolved into water, in which the water-miscible PVA plays as a non-ionic surfactant to help the DPPH reagent to be dissolved into the solvent. Using the DPPH assay, the antioxidant capacity of water-soluble extracts of black soybean, barley, green tea, and green gram was examined. Among the natural products tested, green tea showed the highest antioxidant capacity. This PVA-based DPPH antioxidant assay can be further applied in the natural food, raw plant material, and health product inspection field.

• 동의생리병리학회지
• /
• 제17권6호
• /
• pp.1528-1532
• /
• 2003

To investigate the antioxidant capacity of traditional Korean medicines, water extracts from 57 species were tested on their antioxidant activity using radical scavenging effects against ABTSㆍ+. Of which, Rhus javanica, Caesalpinia sappan, Rosa rugosa, Spatholobus suberectus, and Magnolia obovata showed strong antioxidant capacities at 10㎍ concentration. Therefore, antioxidant capacities of 5 traditional medicine extracts in the different concentration (1㎍, 5㎍, and 10㎍) were determined. The 5 traditional medicine extracts was detected in antioxidant capacity dose dependently. R. javanica was showed the highest antioxidant capacity, the antioxidant activity at 1 ㎍ of herbal extract being 0.85 mM TE. At the same time, the antiperoxidation effects of these 5 medicines were determined. Lipid peroxidation in brain homogenates induced by NADPH and ADP-Fe/sup 2+/ was strong inhibited by S, suberectus, R. rugosa, and M. obovata. Extract of C. sappan was showed the highest inhibition against lipid peroxidation compared with 4 herbal extracts in vitro. These traditional medicines are a potent antioxidant capacity and antiperoxidation activity, further investigation into the in vivo antioxidant therapeutic potential for treatment of human disorders such as Alzheimer's disease.

• Preventive Nutrition and Food Science
• /
• 제22권1호
• /
• pp.21-29
• /
• 2017

The major trend in the antioxidant market is the growing consumer demand for natural antioxidants. Tea, one of the most widely consumed beverages in the world, is an easy way to obtain antioxidant components from a natural source. Our objective was to develop burdock root tea (BRT) with potent antioxidant activity and good color quality. In order to obtain maximum antioxidant activity and quality, the effect of roasting was determined. The antioxidant capacities and total phenolic contents of BRT increased as roasting increased. The color of BRT became darker with increased roasting, extraction time, and amount of burdock roots. Color of BRT was also positively correlated with total antioxidant capacity. Roasting significantly enhanced the total antioxidant activities and color quality of BRT. These results suggest that roasting BRT increases beneficial antioxidant components from burdock roots.

• Advances in materials Research
• /
• 제3권3호
• /
• pp.175-183
• /
• 2014

Natural rubber bound phenolic antioxidant, 2,6-di-tert-butyl-4-vinylphenol (2,6-DBVP), was prepared from natural rubber and 2,6-DBVP in both solution and melt state. The 2,6-DBVP had been synthesized from 3,5-di-tert-butyl-4-hydroxybenzaldehyde and methyltriphenylphosphonium iodide ($MePPh_3I$) by Wittig reaction ($0^{\circ}C$ for 2 hrs, $N_2$ atmosphere). The conditions for preparation of natural rubber bound 2,6-DBVP (NR-DBVP) were optimized for both solution state (1 phr BPO and 8 phr 2,6-DBVP at $70^{\circ}C$ for 2 hrs) and for melt state (1 phr BPO and 8 phr 2,6-DBVP at $70^{\circ}C$ for 10 mins, with rotor speed of 60 rpm). A thermoplastic vulcanizate was obtained using a compatibilizer, polypropylene modified with phenolic resin (PhHRJ-PP), in a closed mixer ($180^{\circ}C$ for 3 mins, rotor speed 60 rpm). The antioxidant properties of vulcanized NR-DBVP, using phenolic as the vulcanization system, were similar to NR with the conventional antioxidant BHT. In addition, the antioxidant, water leaching property of the thermoplastic vulcanizate of NR-DBVP/PP were good in comparison to a NR blend with BHT; the morphologies of these thermoplastic vulcanizates were similar.

• Archives of Pharmacal Research
• /
• 제13권2호
• /
• pp.132-135
• /
• 1990

Polyhydroxystilbenes including resveratrol were reported to competitively inhibit monoamine oxidase-A-without structural relation with substrates and cynthetic inhibitors for the enzyme. We attempt to explore a plausible mechanism for their inhibitory activity on MAO-A. All the polyhydroxystilbenes tested showed the antioxidant activity on liver homogenate. Furthermore, the antioxidant activity turned out to closely correlate with the MAO-A inhibitory activity.

• Food Science and Biotechnology
• /
• 제17권4호
• /
• pp.846-849
• /
• 2008

This study employed high performance liquid chromatography (HPLC) coupled to an on-line $ABTS^+$ radical scavenging detection (RSD) system along with HPLC-electro spin impact/mass spectrometry (ESI/MS), to rapidly determine and identify antioxidant compounds occurring in blueberry extract. The extract was separated by HPLC, and then the radical scavenging activities of the separated compounds were evaluated by the on-line coupled $ABTS^+$-RSD system. The negative peaks of the $ABTS^+$-RSD system, which indicates the presence of antioxidant activity, were monitored by measuring the decrease in absorbance at 734 nm. The active components in the blueberry extract were identified by HPLC-ESI/MS using their MS spectra and retention times. According to the data acquired from the on-line HPLC-$ABTS^+$-based assay and HPLC-ESI/MS systems, the antioxidant compounds detected in the blueberry extract were identified as chlorogenic acid and 11 anthocyanins.

• Journal of Applied Biological Chemistry
• /
• 제50권4호
• /
• pp.270-274
• /
• 2007

Two acetylmartynosides, 2"-acetylmartynoside and 3"-acetylmartynoside were isolated from the $CH_2Cl_2$ fraction of Clerodendron trichotomum (Verbenaceae) by open column chromatography and MPLC. Their chemical structures were identified by the direct comparison of spectral data reported in the literature, and their antioxidant properties were evaluated. Both compounds showed antioxidant activity based on evaluations of intracellular ROS and DPPH radical scavenging activities.

• Journal of Applied Biological Chemistry
• /
• 제59권1호
• /
• pp.57-62
• /
• 2016

In this study, we optimized fermentation conditions for the solid state fermentation of rice bran with Monascus pilosus KCCM60084, and the antioxidant activities were investigated. Optimal fermentation conditions were determined by the production of Monacolin K, a functional secondary metabolites with cholesterol lowering activity. The highest Monacolin K production were 2.88 mg/g observed on day 10 with 45% moisture content in the substrate when inoculated with 5% inoculum (w/w). Reducing power, iron chelating activity and $ABTS^+$ radical scavenging activity were significantly enhanced after fermentation by 60, 80, and 38% respectively. Furthermore, the content of total flavonoid were found to be increased by 4.58 fold. Based on these results, Monascus-fermented rice bran showed strong possibility to be used as a natural antioxidant agent due to its enhanced antioxidant activity.

• 동아시아식생활학회지
• /
• 제22권6호
• /
• pp.758-771
• /
• 2012

This research contains awareness of antioxidant and intakes of antioxidant foods for the present evaluate college students in Seoul, 375 patients were investigated. The subjects, the woman college student more than male's responded, showed a uniform distribution in the allowance, grade and the most type of residence is living apart from their family. All male and female college students recognize a lot about health, but male college students had higher than female students interested in the health, on the other hand, female college students had higher than male college students for the health efforts for the promotion of a healthy. Awareness about the oxide and active oxygen is moderate level, but knowledge about active oxygen is low level, they responded that active oxygen was caused when received stress or do strenuous exercise. General Health Functional Foods recognized that the usual intake, but intake of antioxidant was when the activity was caused by active oxygen. They recognized that the antioxidant effect is anti-aging and vitamin, wine and tea, were perceived as antioxidant foods, are popularly known. Usually, people was initially recognized through the internet in university or high school, they desire to obtain information was high but the effort to gain understanding and knowledge about antioxidant are relatively low. The result of comparing the difference of natural antioxidant foods and antioxidant healthy functional foods, recognizes of effects and absorption rate are similar, but recognizes that natural food intake is better recognition in the economics and health functional food is better recognition in the easy intake and nature foods was more preferred than functional foods because of nature friendly. Trying to intake of antioxidant foods is low, but people is expected anti-aging and fatigue recovery through the intake of antioxidant food. People think that intake is irrelevant to the season, but summer is higher than other seasons. Showed that efficacy perceptions about health supplements are higher, but efficacy perceptions about antioxidant health supplements when ingested are at a moderate level, which is lower, due to low antioxidant for understanding. Antioxidant functional health food intake will be affected the gifts or the people around them and purchase is also more influenced by surround people than themselves. So showed that most college students prefer natural antioxidant foods than antioxidant health supplements, in case of ingested antioxidant health supplements also showed that it was consumed by surround people than personal will.

• 생약학회지
• /
• 제21권4호
• /
• pp.270-273
• /
• 1990

Antioxidant activity of diarylbutane type lignans was evaluated in TBA-reactant assay to elucidate the structure-activity relationship. The antioxidant potency of lignans increased with increasing the number of hydroxyl groups, with the exception of macelignan(I), which showed a more potent activity than demethyl meso-dihydroguaiaretic acid(III).