• Preventive Nutrition and Food Science
• /
• v.11 no.1
• /
• pp.84-87
• /
• 2006

Antioxidant activity of Akebia quinata Decne was evaluated. Water extract (0.5 g/50 mL) of flowers and leaves of A. quinata were prepared and total phenol contents and radical scavenging activity of the extracts was determined for antioxidant activity. The total phenol contents of extracts from A. quinata flowers (FAQ) and leaves (LAQ) were $30.05{\mu}M\;and\;20.23{\mu}M$, while the radical scavenging activity of FAQ and LAQ were 60.51 % and 52.97%, respectively. In addition, the effect of FAQ and LAQ extract on DNA damage induced by $H_2O_2$ in human lymphocytes was evaluated by comet assay. The FAQ and LAQ showed strong inhibitory effect against DNA damage induced by $200{\mu}M$ of $H_2O_2$. These results suggest that water extracts of A. quinata Decne flowers and leaves showed significant (p<0.05) antioxidant activity and protective effect against oxidative DNA damage.

• Natural Product Sciences
• /
• v.18 no.1
• /
• pp.1-7
• /
• 2012

Among 90 Vietnamese medicinal plant extracts investigated for their antioxidant activity by DPPH assay at various concentrations from $10-100{\mu}g/mL$, 67 showed an inhibition rate over 50% at $100{\mu}g/mL$; 47 had greater than 50% inhibition at $50{\mu}g/mL$; 17 showed over 50% inhibition at $25{\mu}g/mL$. 8 extracts which exhibited strong inhibitory activity more than 50% inhibition at $10{\mu}g/mL$ were further tested for lipid peroxidation inhibition by TBA assay. They displayed activity with $IC_{50}$ values from 30.6 to $158.9{\mu}g/mL$. Until now, this is the first report on antioxidant activity of the female flower of Borassus flabellifer, and the stem of Combretum latifolium, Embelia ribes, Spatholobus parviflorus, and Tetrastigma erubescens. Fractionations of the EtOAc extract prepared from S. parviflorus led to the isolation of protocatechuic acid (1), ferulic acid (2), epicatechin (3), and gallic acid (4). These compounds showed significant DPPH inhibitory activity with $IC_{50}$ values from 6.5 to $23.6{\mu}M$.

• Korean Journal of Pharmacognosy
• /
• v.39 no.3
• /
• pp.260-264
• /
• 2008

Eight compounds were isolated from the EtOAc soluble fraction of Euphorbia supina MeOH extract as the radical scavengers for antioxidant activity. Their structures were identified as kaempferol (1), quercetin (2), juglanin (3), avicularin (4), astragalin (5), isoquercitrin (6), hyperin (7), and nicotiflorin (8) by spectroscopic analysis. The antioxidant activity was evaluated by the ORAC (oxygen radical absorbance capacity) assay, which measures scavenging activity against peroxy radicals induced by 2,2'-azobis (2-methylpropionamidine) dihydrochloride, and the ORAC value is expressed as relative trolox equivalent. Compounds 4, 6, and 7 exhibited potent antioxidant activity, whereas the other compounds showed weaker activity than trolox.

• Biomolecules & Therapeutics
• /
• v.7 no.2
• /
• pp.153-157
• /
• 1999

The anticancer effect of medicinal plants against two oral carcinoma cells, A253 and SCC-25 were investigated in this study. Methanol extracts from 63 medicinal plants, which have anticancer activities against other cancers such as stomach, hepatocellular or colon carcinomas, were prepared and screened for their anti- oral cancer activity by using MTT assay. Thirty one samples showed anti-oral cancer activity against either cell line used, however, other 32 samples had no anti-oral cancer activity. Among these samples methanol extract of Caesalpinia sappan revealed the strongest anti-oral cancer activity. The $IC_{50}$/ values of this extract against A253 and SCC-25 cells were 16 and 25 $\mu$g/m1, respectively. Fractions of n-hexane, dichloromethane, ethylacetate, n-buthanol and water were prepared from methanol extracts of Caesalpinia sappan, Anthriscus sylvestris, Rhus japonica, Curcuma arowatica, Inula helenium, Sinoarnudinaria reticulata, and Polygonum cuspidatum, respectively. Among these 35 fractions the n-hexane fraction of Inula helenium showed the strongest anti-oral cancer activity, the $IC_{50}$/ value was 1.6$\pm$0.3 $\mu\textrm{g}$/ml. Ten other fractions showed $IC_{50}$/ values lower than 10 $\mu\textrm{g}$/ml.

• Journal of Life Science
• /
• v.14 no.4
• /
• pp.614-619
• /
• 2004

This study was undertaken to investigate the different responses of cultured plant cells to paraquat treatment and nucleus-DNA damage in relation to enzyme activity of superoxide dismutase (SOD). Furthermore, this study was also carried out to understand the antioxidative mechanism of plant cells to environmental stress. We selected two different species of plant cultured cells, Ipomoea batatas as high-SOD species and Lonicera japonica as low-SOD species. The total activity and specific activity of SOD in a chlorophyllous cell of I. batatas were 3,736 unit/gㆍfresh weight and 547 unit/mgㆍprotein, respectively, and those in L. japonica were 23 unit/gㆍfresh weight and 13 unit/mgㆍprotein, respectively SOD activity in chlorophyllous I. batatas cells reached its maximum level at 10 to 15 days after subculture, whereas that in L. japonica remained at a very low SOD level during the whole period of subculture. In comparison to L. japonica, I. batatas, a high-SOD species, showed high tolerance to paraquat 10 and 50 mg/l treatment in terms of cell viability and electrolyte leakage. Based on the result of comet assay, the nucleus-DNA damage of two species by paraquat 50 mg/l treatment was not significantly different. However, I. batatas cells repaired their damaged DNA more effectively than the cells of the low-SOD species, L. japonica.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.35 no.6
• /
• pp.228-234
• /
• 2021

Hwangryunhaedoktang is one of the prescriptions used in traditional medicine for skin diseases. In this study, Hwangryunhaedoktang-Gamibang (HG) was fermented with Lactiplantibacillus plantarum, a probiotic lactic acid bacterium, to evaluate its potential as a functional cosmetic composition. Strains with anti-inflammatory activity were selected by isolating lactic acid bacteria from kimchi, a traditional Korean fermented food. HG was inoculated with lactic acid bacteria and the viability was measured. The supernatant was obtained by centrifugation of fermented Hwangryunhaedoktang-Gamibang (HGF) and HG, and the filtered supernatant was freeze-dried and used in the experiment. By measuring DPPH and ABTS scavenging activity, it was confirmed that the antioxidant activity was increased. RAW264.7 cells were inoculated with HG and HGF to confirm anti-inflammatory activity through NO assay, and production levels of pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α) were measured through ELISA assay. It was confirmed that HGF had a greater decrease in production than HG. Through lactobacilli fermentation, the beneficial probiotic properties and antioxidant and pro-inflammatory activities of lactic acid bacteria suggest potential clinical or technical applications.

• The Korean Journal of Pesticide Science
• /
• v.9 no.4
• /
• pp.429-436
• /
• 2005

As Sclerotinia sclerotiorum causing cucumber sclerotinia rot was the fastest in the mycelial growth at $25^{\circ}C$, its pathogenicity was strong at the same temperature among several temperatures. All the isolates of Sclerotinia sclerotiorum showed a strong pathogenicity against cucumber fruits, which was confirmed by a disk assay and a wound assay. A wound assay was superior to a disk assay to develop the assay system for assessing the fungicidal activity of several fungicides against Sclerotinia sclerotiorum. In a disk assay, it was very difficult to assess the fungicidal activity, because the pathogenicity of isolates used in the experiment was very strong. At 500 and $3.0{\mu}g/mL$, the activity of dichloflouanid and the mixture of carbendazim and diethofencarb against cucumber sclerotinia rot was 14.3 and 42.3%, respectively, by using a disk assay. However, at same concentration two fungicides showed the high controlling activity as 100 and 92.5%, through a wound assay in a laboratory. Also, the activity of two fungicides was good against cucumber sclerotinia rot in the greenhouse where cucumber plants were cultivated in the field, showing the control value as 91.1 and 82.9% at 100 and $825{\mu}g/mL$, respectively. All the isolates of Sclerotinia sclerotiorum from cucumber fruits sampled in the polyvinyl house were subjected to monitoring for the resistance to 7 fungicides. The $EC_{50}$ value of 7 fungicides was as follows: fenhexamid; $0.13{\mu}g/mL$, procymidon and iprodione; 0.18 and $0.24{\mu}g/mL$, carbendazim and the mixture of carbendazim and diethofencarb; 0.13과 $0.05{\mu}g/mL$, iminoctadine and dichlofluanid; 1.94 and $8.95{\mu}g/mL$. Ultimately it was not found that resistant isolates of Sclerotinia sclerotiorum were appeared in the field.

• Microbiology and Biotechnology Letters
• /
• v.42 no.4
• /
• pp.361-366
• /
• 2014

In this study, Glycyrrhiza uralensis and Glycyrrhiza glabra extracts, with their countries of origin as Korea (Jecheon), Uzbekistan and China, were prepared under various extraction conditions. There were 8 extraction conditions which the licorice were subjected to, and all conditions had different extraction solvents, temperatures and times. Antimicrobial activity on skin flora was evaluated comparatively by a disc diffusion assay, broth macrodilution assay, and kill time curve assay. Based on the antimicrobial activity of their extract confirmed by disc diffusion assay, we established optimal extraction conditions. The Korean licorice extract (85% ethanol, $40^{\circ}C$, 12 h) showed the best activity amongst the samples examined. In particular, its antimicrobial activity against Propionibacterium acnes was the highest. Minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) of the licorice extracts revealed that the Korean licorice ($156{\mu}g/ml$ and $1,250{\mu}g/ml$) had better antimicrobial activity than that of the Uzbekistani licorice ($625{\mu}g/ml$ and $2,500{\mu}g/ml$) and the Chinese licorice ($625{\mu}g/ml$ and $5,000{\mu}g/ml$). Taken together, it was shown that Korean licorice extracted in group F (85% ethanol, $40^{\circ}C$, 12 h) had the highest antimicrobial activity amongst the licorices from the other countries of origin. These results also suggest that the optimal extraction conditions are 85% ethanol, $40^{\circ}C$, 12 h, and that licorice has a potential application as a natural preservative in cosmetics products, thereby replacing synthetic preservatives.

• Journal of Life Science
• /
• v.28 no.7
• /
• pp.765-771
• /
• 2018

Peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) is a key transcription factor that regulates adipogenesis, and epigenetic control of $PPAR{\gamma}$ is of great interest in obesity-inhibition research. Our previous study showed that CACUL1 (CDK2-associated cullin domain 1) acts as a corepressor that inhibits $PPAR{\gamma}$ transcriptional activity and adipocyte differentiation. Here, we investigated the roles of protein arginine methyltransferase 5 (PRMT5), a novel binding partner of CACUL1, in regulating $PPAR{\gamma}$. The interaction between PRMT5 and CACUL1 was shown by immunoprecipitation assay in vivo and GST pulldown assay in vitro. As shown by luciferase reporter assay, PRMT5 and CACUL1 cooperated to inhibit the transcriptional activity of $PPAR{\gamma}$. The suppressive role of PRMT5 in adipogenesis was examined by Oil Red O staining using 3T3-L1 cells, which stably overexpress or deplete PRMT5. Overexpression of PRMT5 suppresses $PPAR{\gamma}$-mediated adipogenesis, whereas PRMT5 knockdown increases lipid accumulation in 3T3-L1 cells. Consistently, PRMT5 attenuates the expression of Lpl and aP2, the target genes of $PPAR{\gamma}$, as demonstrated by RT-qPCR analysis. Overall, these results suggest that PRMT5 interacts with CACUL1 to impair the transcriptional activity of $PPAR{\gamma}$, leading to the inhibition of adipocyte differentiation. Therefore, the regulation of PRMT5 enzymatic activity may provide a clue to develop an anti-obesity drug.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.40 no.7
• /
• pp.1053-1062
• /
• 2011

Reactive oxygen species (ROS), including singlet oxygen (${O_2}^1$), superoxide anion radical ($O_2{\cdot}^-$), hydroxyl radical ($HO{\cdot}$), peroxyl radical ($ROO{\cdot}$), hydrogen peroxide ($H_2O_2$), and hypochlorous (HOCl), are generated as byproducts of normal cellular metabolism. ROS induce damage to many biological molecules, such as lipids, proteins, carbohydrates, and DNA. It is widely believed that some degenerative diseases caused by ROS can be prevented by the high intake of fruits and vegetables due to their antioxidant activities. Recently, research on natural antioxidants has become increasingly active in various fields. Several assays have been developed to measure the total antioxidant capacity of antioxidants in fruits and vegetables in vitro. These assays include those for DPPH radical scavenging activity, SOD-like activity, total polyphenol content, oxygen radical absorbance capacity, reducing power, trolox equivalent antioxidant capacity (ABTS assay), single-cell gel electrophoresis (comet assay), and a cellular antioxidant activity assay. Because different antioxidant compounds may act through different mechanisms in vitro, no single assay can fully evaluate the total antioxidant capacity of foods. Due to the complexity of the composition of foods, it is important to be able to measure antioxidant activity using biologically relevant assays. In this review, recently used assays were selected for extended discussion, including a comparison of the advantages and disadvantages of each assay and their application to fruits and vegetables.