• BMB Reports
• /
• v.44 no.11
• /
• pp.730-734
• /
• 2011

Amyloid ${\beta}$-peptide ($A{\beta}$-peptide)-induced oxidative stress is thought to be a critical component of the pathophysiology of Alzheimer's disease (AD). New chalcone derivatives, the Chana series, were recently synthesized from the retrochalcones of licorice. In this study, we investigated the protective effects of the Chana series against neurodegenerative changes in vitro and in vivo. Among the Chana series, Chana 30 showed the highest free radical scavenging activity (90.7%) in the 1,1-diphenyl-2- picrylhydrazyl assay. Chana 30 also protected against $A{\beta}$-induced neural cell injury in vitro. Furthermore, Chana 30 reduced the learning and memory deficits of $A{\beta}_{1-42}$-peptide injected mice. Taken together, these results suggest that Chana 30 may be a promising candidate as a potent therapeutic agent against neurodegenerative diseases.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.45 no.5
• /
• pp.409-413
• /
• 2012

The physiological activities and amino acid compositions of dried lavers of Porphyra from the Jangheung, Seochen and Haenam coasts were determined. The ethanol extract of the Haenam dried laver exhibited the greatest 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity (56.1%), ferric-reducing antioxidant potential (FRAP) value(86.5 mM) and total polyphenol content (3.51 ppm) of these dried laver products. In addition, there was a strong positive correlation between the antioxidative activity and total polyphenol content of the laver products, suggesting that polyphenol compounds contribute to the antioxidant capacity in the ethanol extract of dried laver. However, there was no difference among the extracts in terms of cell proliferation activity. Fourteen combined amino acids were identified in oligopeptides from the dried laver products. Of the three extracts, that of the Haenam dried laver contained the highest levels of both free and total amino acids including alanine, glutamic acid, taurine, phosphoserine, and aspartic acid.

• Korean Journal of Pharmacognosy
• /
• v.36 no.1 s.140
• /
• pp.34-37
• /
• 2005

Reactive oxygen species (ROS) are known to cause oxidative modification of DNA, proteins, lipids and small cellular molecules and are associated with tissue damage and are the contributing factors for inflammation, aging, cancer, arteriosclerosis, hypertension and diabetes. We screened the anti-oxidants in V79-4 hamster lung fibroblast cells induced by hydrogen peroxide with eighteen pure compounds isolated from natural products. Allantoin, brassicasterol, and hypaconitine were found to strongly scavenge intracellular reactive oxygen species, which is measured by dichlorodihydrofluorescin diacetate method (DCHF-DA), and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical.

• Korean Journal of Pharmacognosy
• /
• v.24 no.4
• /
• pp.299-303
• /
• 1993

The antioxidant activity of methanol extracts of plants and marine algae was tested by using 1,1-diphenyl-2-picrylhydrazyl(DPPH). Five plant extracts(Prunus davidiana, Eriobotrya japonica, Artemisia iwayomogi, Stirodella tolyrrhiza and Ulmus davidiana) and two algae (Ecklonia stolonifera and Symphycoladia latiuscula) were found to be the most effective in DPPH radical scavenging activity. The methanol extract obtained from the stems of Prunus davidiana was fractionated with several solvents. The ethylacetate soluble fraction exhibiting the strongest antioxidant activity was further purified by repeated silica gel and Sephadex LH-20 column chromatography. Antioxidant flavonoids and flavonoid glycosides were isolated and the most active ones was identified as (+)-catechin by MS, $^1H-NMR$ and $^{13}C-NMR$. Its antioxidant activity was higher than that oil vitamin C.

• Journal of the Korean Society of Food Culture
• /
• v.35 no.4
• /
• pp.392-399
• /
• 2020

This study examined the contents of bioactive compounds and the biological activity of okra seed oil. Okra seed oil consisted mainly of linoleic acid (44.2%). The content of total phytosterols was 2.180 mg/g oil, with β-sitosterol being the highest (1.756 mg/g oil). The vitamin E content was 1.278 mg/g oil; the content of α-tocopherol was higher than γ-tocopherol. The total polyphenol and flavonoid contents were 2.463 mg gallic acid equivalent/g and 1.602 mg cathechin equivalent/g, respectively. The 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid and α-α-diphenyl-β-picrylhydrazyl free radical scavenging activities were 15.297% and 22.265%, respectively, and the reducing power was 4.524 mg gallic acid equivalent/g. The okra seed oil inhibited 77.692% of the α-glucosidase activity. The present study showed that okra seed oil had a considerable amount of phytochemicals and exhibited biological activity. These results suggest that okra seed oil is a potential natural therapeutic for the management of metabolic syndromes.

• Korean Journal of Pharmacognosy
• /
• v.45 no.3
• /
• pp.240-248
• /
• 2014

Gyejibokryeong-hwan (GJBRH) has been used for treatment of patients with climacteric syndrome. In this study, an ultra-performance liquid chromatography-electrospray ionization-mass spectrometer (UPLC-ESI-MS) method was established for the simultaneous quantification of seven marker compounds in GJBRH extract. In addition, we assessed the antioxidant effects of GJBRH. All analytes were separated by gradient elution using two mobile phases on a UPLC BEH $C_{18}$ column and maintained at $45^{\circ}C$. The antioxidant activities of GJBRH were evaluated by measuring free radical scavenging activities on 2,2'-azinobis-3-ethyl-benzothiazoline-6-sulfonic acid (ABTS) and 1-1-diphenyl-2-picrylhydrazyl (DPPH). The inhibitory effects on low-density lipoprotein (LDL) oxidation were evaluated by the formation of thiobarbituric acid relative substances (TBARS) and relative electrophoretic mobility (REM). Regression equations of the seven compounds were acquired with $r^2$ values ${\geq}0.9988$. The amounts of the seven compounds, amygdalin, albiflorin, paeoniflorin, coumarin, cinnamic acid, cinnamaldehyde, and paeonol in GJBRH water extract were 21.71, 2.16, 17.17, 1.97, 0.40, 0.78, and 3.42 mg/g, respectively. The GJBRH showed the radical scavenging activity in a dose-dependent manner. The concentration required for 50% reduction ($RC_{50}$) against ABTS and DPPH radicals were $54.18{\mu}g/mL$ and $79.53{\mu}g/mL$. Furthermore, GJBRH reduced the oxidation properties of LDL induced by $CuSO_4$.

• Journal of the Korean Wood Science and Technology
• /
• v.50 no.4
• /
• pp.272-282
• /
• 2022

The essential oil extracted from Citrus × natsudaidai (Yu. Tanaka) Hayata peels is known to have various biological properties. However, the chemical composition of essential oil is influenced by the ripening stages of fruits, which then affects related biological activities. This study investigates the antioxidant activities of essential oils extracted from Citrus × natsudaidai peels at different ripening stages (immature, mature, and overripe). The essential oils were extracted using the hydro-distillation method. As a result of gas chromatography-mass spectrometry (GC-MS) analysis, d-limonene was dominant and was increased as matured. However, 𝛄-terpinene was decreased. The antioxidant properties and their total phenolic content (TPC) were influenced by the ripening stages. The TPC was highest in the immature stage of essential oil (1,011.25 ± 57.15 mg GAE/100 g). 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity was excellent in the immature stage (EC₅₀ = 15.91 ± 0.38 mg/mL). 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity was superior in overripe stage (EC₅₀ = 20.43 ± 0.37 mg/mL). The antioxidant activity measured using ferric reducing antioxidant power (FRAP) assay showed higher values for the essential oils in immaturity (1,342.37 ± 71.07 mg Fe²⁺/100 g). Comprehensively, the essential oil in the immature stage showed the best antioxidant activity. Finally, knowing the chemical composition and antioxidant activity at different ripening stages will provide data for selecting the right fruit.

• Korean Journal of Food Science and Technology
• /
• v.47 no.2
• /
• pp.254-260
• /
• 2015

The effect of the extraction solvent on the physiological properties of the peel of the Korean pear (Pyrus pyrifolia cv. Niitaka) was evaluated. The total phenol content was highest in the 80%(wt) methanol extract, whereas flavonoid content was highest in the 80% ethanol extract. The antioxidant activities of the extracts were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging abilities, and their reducing power. The water and 80% methanol extracts of the pear peel had highest DPPH and ABTS radical scavenging activities, and reducing power, respectively. The inhibition of ${\alpha}$-glucosidase was highest in the 80% methanol extract, and alcohol dehydrogenase activity was highest in the water extract. All three extracts had similar antimicrobial activity. Because water, 80% ethanol, and 80% methanol extracts exhibited high activities in different assays of physiological properties, each solvent could be used for specific purposes.

• The Korea Journal of Herbology
• /
• v.31 no.6
• /
• pp.45-52
• /
• 2016

Objectives : This study was performed to investigate the antioxidant activity of water and ethanol extracts from Sasa borealis leaves, stems and roots. Methods : Sasa borealis leaves, stems and roots extract were prepared using water and ethanol. The total polyphenol and total flavonoid contents were analyzed. 2,2-diphenyl-1-picrylhydrazyl(DPPH) radical scavenging activity, SOD like activity, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)(ABTS), hydroxyl radical scavenging activity, and Nitrite scavenging activity assays were carried out to determine the antioxidant activities. Results : The antioxidant activities of the Sasa borealis appeared higher in ethanol extract than water extracts. Total polyphenol and total flavonoids contents in ethanol extracts of leaves were $24.6mg/m{\ell}$ and $14.3mg/m{\ell}$, respectively, which were much higher than those of any other parts. SOD like activity was 70% ethanol extract of the leaves was highest with 15.68%. Electron donating ability was 70% ethanol extract of the leaves had the highest 59.07%. It exhibited high electron donating ability than BHT(45.68%). Nitrite scavenging activity of 70% ethanol extract was higher than the water extract at pH 2.5 and pH 4.2. Nitrite scavenging activity was 70% ethanol extract of the leaves was the highest 75.2%. Hydroxyl radical scavenging activity was 70% ethanol extract of the leaves was highest with 16.16%, showed very low activity than BHT(61.56%). Conclusions : These results suggest that 70% ethanol extracts from Sasa borealis leaves, exhibited higher antioxidant activities than those of root and stem, and can be potentially used as proper natural antioxidants.

• Journal of Dairy Science and Biotechnology
• /
• v.39 no.4
• /
• pp.157-165
• /
• 2021

This study aimed to determine the effect of extraction temperature and time on the antioxidant activity of hot water extract from Panax ginseng sprout powder and to evaluate the suitability of this extract for use in dairy products. Water-soluble fractions of commercial Panax ginseng sprout powder were obtained by hot water extraction at 25, 60, or 80℃ for 0.5, 2, 12, or 24 h. The antioxidant activity of each extract was evaluated by measuring its free radical scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS). DPPH and ABTS free radical scavenging activity increased with extraction temperature from 25 to 80℃. At 80℃, increasing the extraction time from 0.5 to 2 h led to increases in DPPH and ABTS free radical scavenging activity. Thus, the extract obtained under 2 h at 80℃ was selected for addition to milk and yogurt. After 16 days of storage, there were no significant changes in the pH of the milk or the antioxidant activity of the extract. With regard to yogurt fermentation, adding the extract did not affect the pH or the number of viable lactic acid bacteria. In conclusion, hot water extract from Panax ginseng sprout powder can be added to dairy products to enhance antioxidant activity.