• Korean Journal of Food Science and Technology
• /
• v.40 no.3
• /
• pp.257-264
• /
• 2008

In this study, the antioxidant activities and nitrite scavenging abilities of olive leaf fractions acquired from plants cultivated in Australia (Olea europaea L. var. Picual) and Spain (Olea europaea L. var. Hojiblanca) were evaluated. Oleuropein was found to be the major phenolic compound in the leaves, with the butanol fractions presenting the highest contents. Antioxidant activity was evaluated in terms of superoxide dismutase (SOD)-like activity, 1,1-diphenyl-2-picryl hydroxyl (DPPH) radical scavenging activity, and the inhibitory effect on the auto-oxidation rate of linoleic acid. The SOD-like activities of the olive leaf extracts ranged from 0 to 36.8%. DPPH radical scavenging activity was highest in the ethanol extract of the Australian cultivated olive leaves. Finally, the chloroform fractions of the extracts showed inhibitory effects on the auto-oxidation rate of linoleic acid as well as nitrite scavenging ability.

• Preventive Nutrition and Food Science
• /
• v.13 no.3
• /
• pp.176-181
• /
• 2008

This study analyzed the some of the physiological activities of 70% ethanol extracts of specialty rough rice ('Goami2', 'Keunnunbyeo', and 'Heugkwangbyeo' rough rice cultivars) before and after germination. The physiological activities of the extracts were analyzed for their inhibition of linoleic acid peroxidation, hydrogen peroxide radical scavenging activity, superoxide dismutase-like activity, xanthine oxidase inhibitory activity, and nitrite scavenging effects. The most active rough rice cultivar was 'Heugkwangbyeo' and germinated 'Heugkwangbyeo' rough rice was more effective than ungerminated rough rice, having higher inhibition activity of linoleic acid peroxidation (1.2-fold), hydrogen peroxide radical scavenging activity (1.4-fold), superoxide dismutase-like activity (1.2-fold), and xanthine oxidase inhibitory activity (1.1-fold). The nitrite scavenging effect was increased after germination (2.1-fold) and decreased as pH increased. According to the results obtained in this study, 70% ethanol extracts from germinated 'Heugkwangbyeo' rough rice can be used for industrial applications such as the functional food materials.

• Korean Journal of Plant Resources
• /
• v.24 no.1
• /
• pp.105-112
• /
• 2011

The objective of this study was to determine the effect of antioxidant enzyme activity and radical scavenging activities of thirteen kinds of natural plant pigments. The analytic method of antioxidant activities were measured by estimating DPPH free radical scavenging and nitrite scavenging ability activity. The free radical scavenging activity by method using stable free radical DPPH was the highest in the red cabbaged pigment. Addition of ethanol extract 1mg/ml from onion peel pigment displayed remarkable effect on nitrite scavenging ability about 91.9%. Antioxidative enzyme activity was evaluated in terms of superoxide dismutase(SOD), catalase(CAT), and ascorbate peroxidase(APX) activity. The bitter melon pigment had the highest SOD activity of 87.3%. The activities of CAT and APX were higher in the mulberry leave pigment compared with other natural plant pigments. In contrast, CAT activity of plant pigment samples were unaffected. These results suggest that natural plant pigment had the potent biological activities such as antioxidant enzyme activities, and that their activities exhibited differently depending on each kind of pigments.

• The Korea Journal of Herbology
• /
• v.31 no.6
• /
• pp.21-28
• /
• 2016

Objectives : This study was performed to investigate the antioxidant activity of water extracts from Lycopus lucidus Turcz. ex Benth. leaves, stems and roots at the $100{\mu}g/m{\ell}$ concentration. Methods : The different part of Lycopus lucidus Turcz. ex Benth. extract was prepared using water. The antioxidant activities of polyphenol contents, total flavonoid contents, DPPH(1,1-diphenyl-2-picrylhydrazyl) free-radical scavenging activity, SOD like activity, hydroxyl radical, ABTS(2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), $Fe^{2+}$ chelating, and nitrite scavenging activity. Results : The total polyphenol and total flavonoid content of leaves were the highest at $221.85{\mu}g/mg$ and $794.13{\mu}g/mg$, respectively. Electron donating ability was the 79.68% in the water extract from leaves. The ABTS radical scavenging activity of the hot extracts, leaves ${\gg}$ roots > stems was higher in the order. It was shown the highest at 94.53% in the water extract from leaves, which showed a value equal to 94.7% of ascorbic acid. The hydroxyl radical scavenging activity was the highest at 8.07% in the water extract from leaves. SOD like activity and $Fe^{2+}$chelating activity were leaves of 12.3% and 27%, respectively, which were much higher than those of any other parts. The nitrite scavenging ability of extracts was increased at pH 2.5, and those was the highest in leaves of 83.03%. Its were more than twice the 41.61% of BHT. Conclusion : The results suggest that Lycopus lucidus Turcz. ex Benth. can be used as nutraceutical foods and natural antioxidant.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2019.10a
• /
• pp.88-88
• /
• 2019

Antioxidants are involved in the defense mechanism against the attack of free radicals. This study was carried out to determine the antioxidant activity of new variety of Glycyrrhiza cultivar radix, Wongam and Sinwongam. Dissolved freeze dried Wongam and Sinwongam extracts were filtered by $0.2{\mu}m$ filter and serially diluted at the concentrations of $10{\mu}g/mL$, $50{\mu}g/mL$, $100{\mu}g/mL$, $500{\mu}g/mL$, and $1000{\mu}g/mL$. The antioxidant potential was determined by DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity, ABTS (2,2-azino-bis (3-rthylbenzthiazoline-6-sulfonic acid) diammonium salt) radical cation decolorization assay, nitrite radical scavenging assay, and ferric reducing antioxidant power (FRAP) assay. DPPH radical scavenging activities (i.e. the highest value $50.9{\pm}0.8%$ by Wongam and $82.6{\pm}1.1%$ by Sinwongam), ABTS radical scavenging activities (i.e. the highest value $88.1{\pm}1.8%$ by Wongam and $98.6{\pm}0.1%$ by Sinwongam), and nitrite radical scavenging activities (i.e. the highest value $87.3{\pm}1.6%$ by Wongam and $89.8{\pm}0.8%$ by Sinwongam) increased in a dose-dependent manner. In addition, ferric reducing power activities also increased in a dose-dependent manner. The FRAP value of Wongam and Sinwongam extracts were $0.72{\pm}0.03$ and $0.99{\pm}0.06$ compared to ascorbic acid, as a positive control, was $1.32{\pm}0.02$. These results suggested that Wongam and Sinwongam have beneficial effects as a potent antioxidant.

• Korean Journal of Food Science and Technology
• /
• v.46 no.2
• /
• pp.205-212
• /
• 2014

This study was designed to investigate the antioxidant activities (ORAC value, DPPH and ABTS radical scavenging activity, FRAP activity, and reducing power) and nitrite scavenging activities of Acanthopanax senticosus extracts fermented with the mycelia of three different mushroom species: Ganoderma lucidum, Phellinus linteus, and Hericium erinaceus. The highest total phenol content (42.09 GAE mg/g) and ORAC value ($74,912{\mu}M$ TE/g) were observed in a hot water extract of A. senticosus fermented with G. lucidum. The highest DPPH radical and nitrite scavenging activities were observed in a 70% ethanol extract of A. senticosus fermented with G. lucidum. In addition, ABTS radical scavenging activity (8-88%), FRAP activity (0.1-0.2), and reducing power (0.3-0.7) were increased by ethanol addition in all samples in a dose-dependent manner. These results provide a basic understanding of the antioxidant and nitrite-scavenging activities of A. senticosus extracts fermented with different mushroom mycelia.

• Korean Journal of Food Science and Technology
• /
• v.32 no.4
• /
• pp.928-935
• /
• 2000

This study was carried out to examine the antioxidative, antimicrobial and nitrite scavenging effects of various solvent extracts and different solvent fractions from Schizandra chinensis RUPRECHT(Omija) seed. The results were as follows; The antioxidative activities using lard, soybean oil and linoleic acid were the highest in methanol, ethanol and methanol extract from omija seed, respectively. The free radical scavenging activity using DPPH method was the strongest in acetate fraction of methanol extract from seed. The methanol extract from omija seed had the strongest antimicrobial activities to L. plantarum, B. subtilis, E. coli and P. citrinum, while ethyl acetate extract had the strongest against S. aureus and S. typhimurium. The buthanol fraction from methanol extract had the highest antimicrobial activities, followed by B. subtilis, L. plantarum, E. coli, S. aureus and S. typhimurium. The nitrite scavenging ability was pH dependent, highest at pH 1.2 and lowest at pH 6.0. The buthanol fraction of methanol extract from omija seed had more effective nitrite scavenging ability than other fractions of extracts.

• Korean Journal of Plant Resources
• /
• v.21 no.4
• /
• pp.292-298
• /
• 2008

The antioxidant activities of Artemisia capillaris and Artemisia iwayomogi used as Injin (Korean herbal name) were investigated. The DPPH radical scavenging activity of the ethylacetate fractions obtained from the Artemisia capillaris and Artemisia iwayomogi was higher than other fractions. No DPPH radical scavenging activity was observed in hexane frcations. The nitrite scavenging activity was the highest at pH 1.2, and the peroxide value for linoleic acid was increased during the incubation.

• The Korea Journal of Herbology
• /
• v.34 no.1
• /
• pp.59-65
• /
• 2019

Objectives : This study reviewed the antioxidant activity of each part of Portulacae Herba (PH) in order to better analyze the possibility of PH being used as a natural material. Methods : The root, stem, and leaves of the PH were separated, dried at $50^{\circ}C$, put in a 70% ethanol and then extracted three times every six hours. Antioxidant activities was performed by measuring the total polyphenol and total flavonoid contents, DPPH, ABTS, nitrite, hydroxyl radical scavenging activity, and $Fe^{2+}$ chelating. Results : The total polyphenol and total flavonoid contents was highest in the root, then the leaves, and lastly the stem. DPPH and ABTS radical scavenging activities for the root extract indicated the highest activity followed by the leaf and stem extracts. It also showed similar activity to that of the ascorbic acid. Hydroxyl radical scavenging activity and $Fe^{2+}$ chelating activity resulted to be highest in the root extract and then the leaf and stem extracts. Nitrite scavenging activity decreased with higher pH levels, and activity was highest in the order of root extract, leaf extract, and stem extract. Also, in reaction to a solution with a pH 1.2 level, the root extract showed similar scavenging activity to that of BHT. Conclusions : Therefore, based on the above results, it was verified that the roots of PH have a high antioxidant level, and they can be considered to have potential to be applied to functional food, cosmetics, and medicine with antioxidant efficacy.

• Preventive Nutrition and Food Science
• /
• v.17 no.2
• /
• pp.116-121
• /
• 2012

Water extract from Pinus densiflora (WPD) was investigated for its antioxidant activity and its ability to provide protection from DNA damage. A series of antioxidant assays, including a 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenging assay, a reducing power assay, a metal-chelating assay, a superoxide radical scavenging assay, and a nitrite scavenging ability, as well as a DNA damage protection assay were performed. Total phenolic content was found to be 211.32 mg Tan/g WPD. The extract scavenged 50% DPPH free radical at a concentration of 21.35 ${\mu}g/mL$. At that same concentration, the reducing power ability of WPD was higher than that of ${\alpha}$-tocopherol. The extract chelated 68.9% ferrous ion at the concentration of 4 mg/mL. WPD showed better nitrite scavenging effect at the lower pH. Meanwhile, WPD exhibited a strong capability for DNA damage protection at 1 mg/mL concentration. Taken together, these data suggest water extract from Pinus densiflora could be used as a suitable natural antioxidant.