• The Korean Journal of Pesticide Science
• /
• v.7 no.2
• /
• pp.92-99
• /
• 2003

A 96-well plate was applied to determine the DPPH free radical scavenging activity using 107 plant-specific enzyme inhibitors and 100 unknown plant-originated extracts. The final optimum volume was $250{\mu}L$ containing $100{\mu}M$ DPPH ethanolic solution at pH 7.8. In this condition, the radical scavenging activities were significantly increased by two known antioxidants consisting of ascorbate and a-tocopherol in a concentration-dependent manner. Among the 107 inhibitors, ampicillin and gallic acid showed 90.2% and 92.6% antioxidant activity at $100{\mu}M$, respectively, and these results were consisted with previous findings. In the tested 100 natural materials at $50{\mu}g/mL$, antioxidant activity of AT-407 resulted in the highest of 90.1%, and 10 extracts including AT-388 and AT-443 showed over 70%. Our results suggest that the use of 96-well plate for determining DPPH free radical scavenging activity would be a suitable method to select antioxidant-like substances of both synthetic compounds and natural products.

• FLOWER RESEARCH JOURNAL
• /
• v.17 no.4
• /
• pp.271-278
• /
• 2009

The attempts to develop natural antioxidants have been made with aerial part of 16 Compositae species by analyzing their phenolic compound contents, scavenging activities on 1,l-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radicals, ferrous ion chelating effects and inhibition effects on peroxidation of linoleic acids. Total polyphenol and flavonoid contents were highest in Matricaria recutica. Scavenging activity on DPPH and ABTS radicals were highest with extracts of Echinacea angustifolia and Serratula coronata var. insularis f. insularis, respectively. Aerial palt extracts of all species showed lower DPPH scavenging activity than ascorbic acid and 2,6-Di-tert-butyl-4-methylphenol (BHT). But Serratula coronata var. insularis f. insularis demonstrated higher ABTS scavenging activity than ascorbic acid and BHT. In Hieracium pilosella, Echinacea angustifolia, Matricaria reculica extracts showed higher ABTS scavenging activity than BHT. Ferrous ion chelating effects was highest with Matricaria recutica extract, but the effects were much lower than ethylenediaminetetraacetic acid (EDTA). The inhibition activity in lipid peroxidation of linoleic acids was highest in Eupatorium japonicum with 90.06% inhibition 4 days after reaction and 40.52% after 24 days. This demonstrated higher inhibition activity and longer lasting than BHT. Aerial part of Matricaria recutica for extraction source, rather than flower, has higher potential for antiox.idant material. In conclusion, development of natural antioxidants in Compositae is possible by studying antioxidant activity of each species.

• Korean Journal of Food Science and Technology
• /
• v.53 no.1
• /
• pp.55-62
• /
• 2021

This study was conducted to investigate the potential of sea buckthorn leaf (SBL) as a natural antioxidant. SBL was extracted using different ethanol ratios (0, 40, 80, and 100%), and the resulting extracts were examined for their antioxidant contents and antioxidant activities using various methods. The 40% and 80% ethanol extracts (EEs) showed higher total polyphenol contents of 285.06 and 285.64 mg GAE/g respectively, than those in other solvents, and as the ethanol concentration increased, other antioxidant contents of the extracts increased. The 40% and 80% EEs recorded the highest radical scavenging activities against DPPH, superoxide-, ABTS+, nitrite scavenging activity (NO-), and reducing power (RP). The NO- and RP of the SBL EEs were higher than those of ascorbic acid or tannin, which are known as representative antioxidants. The results of this study, suggest that SBL is a potential source of natural antioxidants.

• Advances in Traditional Medicine
• /
• v.8 no.2
• /
• pp.154-163
• /
• 2008

The methanol extract of stem barks of Careya arborea Roxb. (MECA) (Family- Myrtaceae) was evaluated for antitumor activity and antioxidant status against Ehrlich's Ascites Carcinoma (EAC) bearing Swiss albino mice. After 24 h of tumor inoculation the MECA was administered at the doses of 50, 100 and 200 mg/kg body weight/mice/day for 14 days. After the last dose and 18 h fasting mice were sacrificed. The effect of MECA on the growth of transplantable murine tumor, life span of EAC bearing hosts, hematological profiles, serum and liver biochemical parameters were estimated. The MECA showed significant (P < 0.01) decrease in ascites volume, packed cell volume and viable cell count and prolonged the life span of EAC tumor bearing mice. Hematological profiles reverted to more or less normal levels in extract treated mice. The MECA also produced protective effect by decreasing the activity of serum enzymes, bilirubin and increase the protein and uric acid levels. MECA significantly (P < 0.05) decreased the levels of lipid peroxidation, while significantly (P < 0.05) increased the levels of glutathione content, vitamin C, vitamin E, superoxide dismutase and catalase CAT. The results indicate that MECA exhibited significant antitumor and antioxidant activity in EAC bearing mice.

• Food Science of Animal Resources
• /
• v.38 no.4
• /
• pp.737-748
• /
• 2018

We evaluated the physicochemical and storage characteristics of Hanwoo Tteokgalbi treated with onion skin powder (OSP) and blackcurrant fruit powder (BFP). The experimental design included seven treatments: a control (ascorbic acid 0.1%), T1: OSP 0.3%, T2: OSP 0.6%, T3: BFP 0.3%, T4: BFP 0.6%, T5: OSP 0.15%+BFP 0.15%, and T6: OSP 0.3%+BFP 0.3%. The OSP was higher in both polyphenol and flavonoid contents compared to BFP (p<0.05). The moisture and ash contents of all Tteokgalbi samples with a large amount of added natural antioxidant powder (0.6%) were higher than those with small amounts of added antioxidant (0.3%). The cooking loss and water holding capacity were outstanding in the T2 treatment compared to the others (p<0.05). The lightness, redness, and yellowness values were reduced on the addition of 0.6% antioxidant powder (p<0.05). The springiness and cohesiveness values of the Tteokgalbi samples were higher for the 0.3% addition than the control and 0.6% addition (p<0.05). The Tteokgalbi samples with natural antioxidants showed similar sensory attribute scores compared to the control. The pH values reduced as the BFP increased (p<0.05), and the total microbial count increased after OSP addition. The 2-thiobarbituric acid reactive substance values of the samples treated with OSP were significantly lower than the control after day 10 (p<0.05). As a result, the addition of OSP or BFP did not have a significant negative influence on the quality characteristics of Hanwoo Tteokgalbi. In particular, the addition of 0.6% OSP was effective in increasing water retentivity and inhibiting lipid oxidation.

• Nutrition Research and Practice
• /
• v.4 no.2
• /
• pp.114-120
• /
• 2010

The effects of grape seeds extract and grape peels extract prepared from grape pomace on the activity of antioxidant enzymes, degree of lipid peroxidation in serum and liver tissue were investigated in rabbits fed on high cholesterol diet. New Zealand white rabbits were divided as follows ; 1) NOR (normal group); 2) CHOL (cholesterol group); 3) GSH (cholesterol + grape seed extract group); 4) GPE (cholesterol + grape peel extract); 5) GSP (cholesterol + grape seed powder); 6) GPP (cholesterol + grape peel powder); 7) GE (cholesterol + grape seed and peel extract); 8) GP (cholesterol + grape seed and peel powder). Eight groups of rabbits were studied for 8 weeks. At the end of the experimental period, rabbits were sacrificed and the liver tissue were removed. Then, GSH, GPx, GST, CAT and MDA in the liver were measured. In liver tissues, total glutathione contents (GSH), glutathione peroxidase (GPx) and catalase (CAT) activity, which was significantly higher by grape seed extract supplementation. The level of malondialdehyde (MDA) was lower in the serum of rabbits fed grape seed extract or grape peel powder plus cholesterol than in the serum of rabbits fed cholesterol alone. It is therefore likely that grape seed extract prepared from grape pomace functioned as antioxidants in vivo, negating the effects of the oxidative stress induced by 1% cholesterol diet. The grape seed extract was found effective in converting the oxidized glutathione into reduced glutathione, and in removing $H_2O_2$ that is created by oxidative stress. The grape peel powder was found to have small influence on reduced glutathione content, CAT and GPX activity, but it increased GST activity in liver tissues, resulting in promoting the combination of lipid peroxide and glutathione (GSH), and further, lowering the formation of lipid peroxide in the serum. Therefore, grape pomace (grape seed extract and grape peel powder) supplementation is considered to activate the antioxidant enzyme system and prevent damage with hypercholesterolemia.

• The Journal of Natural Sciences
• /
• v.18 no.1
• /
• pp.39-46
• /
• 2007

Three kinds of plant fermentation broths and one liquor were prepared using persimmon, Ulmus davidiana var. japonica and barley, and investigated its physiological functionality. Anti-aging antioxidants activity was the highest of 99% in Ulmus dacidiana bar. japonica liquor and also was high in the persimmon vinegar(68.3 %). SOD-like activity show also 80.6% in the Ulmus davidiana var japonica liquor however the other fermentation broths were less 25%. Antihypertensive angiotensin I-converting enzyme inhibitory activity and fibrinolytic activity were weak or not detected in all the fermentation broths. Anti-dementia acetylcholinesterase inhibitory activity were showed 54.7% in the Ulmus davidiana var. japonica liquor. Our results showed that the Ulmus davidana var. japonica liquor has the potential to become a new functional liquor because of high antioxidant activity and anti-dementia activity.

• Journal of the Korean Dietetic Association
• /
• v.4 no.2
• /
• pp.168-177
• /
• 1998

It has been reported that cigarette smoking increases free radical generation, which can also increase lipid peroxides and deplete antioxidants. The purpose of this study was to determine whether cigarette smoking and other lifestyle choices may affect serum lipid peroxide concentrations, serum antioxidant concentrations such as tocopherol and vitamin C, and serum antioxidant enzyme activity such as glutathione peroxidase and superoxide dismutase. Dietary intakes were assessed by 24-hour recall and survey questionnaires from 48 male non-smokers and 52 male smokers. Overnight fasting blood was collected and measured for individual antioxidant status. The daily vitamin C intakes of smokers tended to be lower than those of non-smokers, and the intakes of both groups were under the Recommended Daily Allowance (RDA). Vitamin E intake was sufficient for smokers and non-smokers. Serum lipid peroxide concentrations were no difference among all subjects. The serum $\alpha$-tocopherol concentrations of all subjects were in a normal range, and they were highest in mild smokers (p<0.05). Mean serum vitamin C levels were lowest in heavy smokers (p<0.05). The activities of serum glutathione peroxidase and superoxide dismutase were not significantly different in smokes and non-smokers. In conclusion, smoking did not increase oxidative stress in heathy young men. However, it is desirable for heavy smokers to consume more vitamin C than the RDA sine their serum vitamin C concentrations are relatively low.

• Animal cells and systems
• /
• v.13 no.2
• /
• pp.133-139
• /
• 2009

Green tea seed was extracted with absolute ethanol,and the green tea seed extract(GTSE)was subjected to assays for toxicity, antioxidant ability, angiogenesis inhibitory effects and cell adhesion, as well as western blotting, and an in vivo experiment against 4 high-ranking adult cancers in Korea. Our series of experimental data demonstrated that GTSE has an antioxidant ability superior to that of EGCG in the green tea leaf, and also exhibits a profound high tumor growth inhibitory activity on a variety of cancer cell lines, as well as nude mice infected with cancer cells. GTSE was identified as a natural anticancer compound showing excellent angiogenesis inhibition and cancer cell suppression abilities. Our preliminary observations also indicate that GTSE may be another potential source of natural dietary antioxidants and also may be applicable as a novel natural anticancer agent.

• Archives of Pharmacal Research
• /
• v.24 no.4
• /
• pp.307-311
• /
• 2001

The activation of NF-$\kappa$B induced by kojic Acid, an inhibitor of tyrosinase for biosynthesis of melanin in melanocytes, was investigated in human transfectant HaCaT and SCC-13 cells. These two keratinocyte cell lines transfected with pNF-$\kappa$B-SEAP-NPT plasmid were used to determine the activation of NF-$\kappa$B. Transfectant cells release the secretory alkaline phosphatase (SEAP) as a transcription reporter in response to the NF-$\kappa$B activity and contain the neomycin phosphotransferase (NPT) gene for the dominant selective marker of geneticin resistance. NF-$\kappa$B activation was measured in the SEAP reporter gene assay using a fluorescence detection method. Kojic Acid showed the inhibition of cellular NF-$\kappa$B activity in both human keratinocyte transfectants. It could also downregulate the ultraviolet ray (UVR)-induced activation of NF-$\kappa$B expression in transfectant HaCaT cells. Moreover, the inhibitory activity of kojic Acid in transfectant HaCaT cells was found to be more potent than known antioxidants, e.g., vitamin C and N~acetyl-L-cysteine. These results indicate that kojic Acid is a potential inhibitor of NF-$\kappa$B activation in human keratinocytes, and suggest the hypothesis that NF-$\kappa$B activation may be involved in kojic Acid induced anti-melanogenic effect.