• Journal of Life Science
• /
• v.33 no.7
• /
• pp.549-554
• /
• 2023

Korean ginseng has been used for centuries in traditional Chinese medicine as an overall wellness supplement. Red ginseng (Ginseng Radix Rubra) is produced by steaming the roots, followed by drying. Soft red ginseng is produced using a new processing technology. This study investigated whether soft red ginseng differs from raw and hard red ginseng in its physicochemical composition. Results showed that the total phenol content of raw ginseng was 2.96 mg/g at 80℃ and 3.47 mg/g at 160 ℃. Meanwhile, the total phenols of hard and soft red ginseng were 4.12 mg/g and 4.18 mg/g at 160℃, respectively. The total phenol contents of raw, hard red, and soft red ginseng revealed a statistically significant difference (p>0.05). The total flavonoid contents of raw, hard red, and soft red ginseng were 2.62 mg/g, 3.97 mg/g, and 3.83 mg/g at 160℃, respectively. Among the three samples, soft red ginseng had the highest total sugar content at 160℃. The acidic polysaccharide contents of both soft and hard red ginseng were much higher than that of raw ginseng (49%-58%). Significant differences were observed among raw, hard red, and soft red ginseng (p<0.001). Soft red ginseng exhibited higher phenol content (25%), total flavonoid content (49%), and total sugar content (45%) than raw ginseng.

• Food Science and Biotechnology
• /
• v.18 no.3
• /
• pp.624-629
• /
• 2009

In order to evaluate the bioactivity of 'Agakong3', which was newly bred, quinone reductase (QR) inductive activity and antioxidant activity were both assessed. The methanol extract of 'Agakong3' showed a significantly stronger QR inductive activity than other soybeans. The methanol extract of 'Agakong3' also showed a significantly stronger cytotoxicity on hepa1c1c7 than other soybeans. 'Agakong3' exhibited the most potent antioxidant activity in the Trolox equivalent antioxidant capacity (TEAC) assay whereas it showed significantly weak antioxidant in the DPPH assay. In total phenol and flavonoid contents, 'Agakong3' showed the highest contents regarding phenol and flavonoid compounds. Major isoflavones such as daidzein and genistein were quantitified by high performance liquid chromatography. 'Agakong3' also showed the highest total isoflavone contents. Results of correlation analysis showed that there were high correlation coefficients between the contents of isoflavone and TEAC and the contents of isoflavone and QR inductive activity, respectively. These results suggest that 'Agakong3' will be a promising and functional food material.

• The Korean Journal of Food And Nutrition
• /
• v.34 no.2
• /
• pp.174-180
• /
• 2021

The purpose of this study was to determine the optimum extraction method suitable for the availability of biological activities in unripe apples known to be rich in functional components. Unripe apples 'Hongro' picked on May 28th, 2019 were extracted by various extraction methods (hot water, ethanol, enzymatic pre-treatment, ultrasonic wave, and subcritical water) and their extracts were investigated yield, effective component contents, and antioxidant activities. Overall, the yields by the extraction solvent were higher in water than in organic solvent(ethanol) because water-soluble compounds were eluted from a polar solvent. Total phenol contents of the ultrasonic wave (ethanol) extracts were significantly higher in 6 times than hot water extract. Contents of flavonoid were highest in the ethanol extract at 29.14 mg QE/g. Contents of tannin and ursolic acid were also significantly higher in the ultrasonic wave (ethanol) extract. The DPPH radical and ABTS radical scavenging activities were the strongest in the ultrasonic wave (ethanol) extract. Correlation between effective components and antioxidant activities was high in the total phenol content with ABTS and the ursolic acid content with DPPH (p<0.01). The above results suggested that ultrasonic wave (ethanol) extract of unripe apples has the potential to act as a functional material.

• Journal of Haehwa Medicine
• /
• v.23 no.1
• /
• pp.105-114
• /
• 2014

Objectives : In this study, the antioxidant activities of the 80% ethanol and hot water extracts of Euphorbia supina Rafinesque were investigated. Methods : We measured total phenol contents, flavonoid contents, 2,2-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging assay. The production of reactive oxygen species was measured in LPS-induced RAW 264.7 cells using flow cytometry system. Results : The content of phenol in the hot water extract was $65.529{\pm}0.462mg/g$ and $126.932{\pm}1.894mg/g$ in the 80% ethanol extract, and that of flavonoid in the hot water extract was $16.063{\pm}0.471mg/g$ and $29.159{\pm}1.963mg/g$ in the ethanol extract. The 80% ethanol extract also showed higher DPPH and ABTS radical scavenging activities ($90.8{\pm}1.0%$ and $92.5{\pm}0.7%$) than the hot water extract ($81.5{\pm}0.5%$ and $91.5{\pm}0.2%$). The production of reactive oxygen species(ROS) was reduced dose-dependently by 80% ethanol and hot water extract at concentration of 1, 10 and $100{\mu}g/m{\ell}$ of RAW 264.7 cells. Conclusion : According to these results, the 80% ethanol extract of Euphorbia supina Rafinesque has a good anti-oxidative effects than the hot water extract. Thus, the 80% ethanol extract of Euphorbia supina Rafinesque may serve as useful natural antioxidants.

• Journal of the Korean Applied Science and Technology
• /
• v.33 no.3
• /
• pp.474-482
• /
• 2016

The black raspberry (Rubus coreanus Miquel) contains anthocyanin, tannins, gallotannin, gallic acid, ferulic acid and phenolics. It brightens the eyes and protects the liver and kidneys. It was effective for anti-aging. Thus, the purpose of this study was to inform the excellence of black raspberry and to screen antioxidant activity to ensure the possibility as a functional material. In this study, bioactive compounds in black raspberry were determined. Additionally, black raspberry was extracted by CM (chloroform:methanol, 2:1, v/v), 70% methanol and 70% ethanol, and were investigated and compared in vitro methods. Total phenol and flavonoid contents were measured to compare each different solvents. In addition, DPPH radical scavenging activity and ABTS radical scavenging activity, ferric reducing antioxidant power, reducing power were determined to measure the antioxidant activity. The results were the highest in 70% ethanol extracts, and the higher the concentration showed a significantly higher antioxidant capacity. When observed the relationship between the study, antioxidant activity of black raspberry was supposed to affect by the anthocyanin, phenol and flavonoid contents.

• Applied Chemistry for Engineering
• /
• v.24 no.2
• /
• pp.121-125
• /
• 2013

In this work, we prepared the carbon paper from chopped carbon fibers using a gas diffusion matrix in polymer electrolyte membrane fuel cells by wet processing. The process of making carbon paper using wet processing is consisted of the three steps involving the dispersion of chopped carbon fibers, the preparation of the carbon fiber web, the impregnating of phenol resin. This work was focused on finding the optimal surfactant to make the carbon paper with 2D orientation of carbon fibers by investigating the dispersion state of carbon fibers in different dispersion solutions. Furthermore, the effect of phenol resin and carbon black contents on properties of electric conductivity was analyzed. As a result, it is confirmed that the carbon fiber was well dispersed when using sodium dodecyl sulfate as a surfactant, and the carbon paper with 8 wt% of phenol and 5 wt% of carbon black contents showed the most excellent electrical property.

• The Korean Journal of Food And Nutrition
• /
• v.33 no.1
• /
• pp.64-73
• /
• 2020

The purpose of this study was to investigate the antioxidant activity and β-glucan content of extracts extracted by varying the temperature at 30, 55 and 80℃ after hot air drying or freeze drying of Pleurotus ostreatus and Pleurotus eryngii. For the analysis antioxidant activity of each mushroom, β-glucan, total phenol, flavonoid contents, and DPPH·ABTS⁺·Nitrite assay were measured. Also, the β-glucan content, total flavonoid content and ABTS⁺ scavenging activity increased with freeze drying rather than hot air drying, and increased with increasing extraction temperature in both mushrooms. However, the total phenol and nitrite scavenging activity increased with hot air drying rather than freeze drying, and decreased with increasing temperature in both mushrooms. DPPH scavenging activity was not significant in both mushrooms, but decreased with increasing extraction temperature. Pearson's correlations between total flavonoid content and antioxidant activities were r=0.719~0.753 (p<0.01). As a result, the β-glucan content, total flavonoid content, and ABTS radical cation scavenging activity were highest during freeze drying and extraction at 80℃. And the highest total phenol content, DPPH radical scavenging activity and nitrite scavenging activity were obtained during hot air drying and extraction at 30℃.

• Food Science and Preservation
• /
• v.15 no.3
• /
• pp.325-331
• /
• 2008

The propose of this study was to investigate the antioxidant activity of 80% ethanol extracts and various solvent fractions of dandelion (Taraxacmn officinale) leaves and roots, Total phenolics and phenolic acid contents were also examined. The total phenol content of leaves and roots were $7.9{\pm}0.4%$ and $9.4{\pm}0.3%$ respectively. Eight phenolic acids were separated by GC, among which caffeic acid (113.7 mg%)and m-coumaric acid (152.6 mg) were the dominant phenolic acids in leaves and roots, respectively. Amongst solvent functions of leaves and roots, the ethyl acetate fraction showed the strongest radical scavenging activity. A strong correlation was found between total phenol content and electron-donating ability, and ABTS radical scavenging activity showed a similar trend as electron-donating ability. Hydroxyl-radical-scavenging activity and lipid peroxidation were significantly higher in the ethyl acetate fraction than other factions. In particular, the SOD-like activity was highest (43.6%) in the ethyl acetate fraction of dandelion leaves, and was higher than that of trolox. Thus, the ethyl acetate fraction of dandelion leaves exhibited significant phenol content, antioxidant activity, and free-radical-scavenging effects.

• Bulletin of the Korean Chemical Society
• /
• v.31 no.12
• /
• pp.3567-3572
• /
• 2010

Black pine barks from the southern region of Korea were extracted using pressurized hot water and the water soluble extracts were then separated in a stepwise fashion using a variety of solvents, column chromatography (CC), thin layer chromatography (TLC), and high pressure liquid chromatography (HPLC). The antioxidant activities of each fraction and the active compounds were determined based on the radical scavenging activities of 2,2-diphenyl-1-picrylhydrazyl (DPPH), reductive potential of ferric ion, and total phenol contents. A DPPH test showed that the half maximal effective concentration ($EC_{50}$ value : $6.59{\pm}0.31\;{\mu}g/mL$) of the ethyl acetate fraction (ca. 0.67%) was almost the same as that of the control compounds and inversely proportional to the value of the total phenol contents. The cell viability of the water extracts was confirmed by methyl thiazol-2-yl-2,5-diphenyl tetrazolium bromide (MTT) with enzyme linked immune sorbent assay (ELISA). Catechin, epicatechin, quercetin and ferulic acid were isolated from the ethyl acetate fraction as active compounds and identified by nuclear magnetic resonance. The antioxidant activity as value of DPPH of each of the separated compounds was lower than the ethyl acetate fraction, and ferulic acid was the lowest among these compounds.

• Journal of Environmental Science International
• /
• v.23 no.7
• /
• pp.1233-1239
• /
• 2014

Watermelon (Citrullus vulgaris L.) is a summer fruit typical to help fatigue systemic absorption is getting better. The goal of this study is to screen antioxidant activity to ensure the possibility as a functional material for exocarp of watermelon. Watermelon was extracted with 70% methanol, 70% ethanol, chloroform:methanol (CM, 2:1, v/v). Total phenol contents were 12.01 mg/g, 8.89 mg/g, 3.53 mg/g in the 70% methanol, 70% ethanol, CM, in that order, respectively. Total flavonoid content, DPPH radical scavenging activity, ABTS radical scavenging activity, ferric reducing antioxidant power (FRAP), ${\beta}$-carotene bleaching assay were 70% methanol extract remarkably higher than the other extracts. And these results showed the same trend of total phenol content. From the above results shows that watermelon was effective on the antioxidative activity.