• Journal of Microbiology and Biotechnology
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• v.28 no.5
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• pp.679-687
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• 2018

Korean red pine (Pinus densiflora) is one of the major Pinus species in Korea. Red pine bark is removed prior to the chipping process in the wood industry and discarded as waste. However, red pine bark contains a considerable amount of naturally occurring phenolics, including flavonoids, and therefore may have a variety of biological effects. In this study, we investigated if Korean red pine bark extract (KRPBE) could protect neuronal PC-12 cells from oxidative stress and inhibit cholinesterase activity. Analysis of reversed-phase high-performance liquid chromatography results revealed four phenolics in KRPBE: vanillin, protocatechuic acid, catechin, and taxifolin. The total phenolic and flavonoid contents of KRPBE were 397.9 mg gallic acid equivalents/g dry weight (DW) and 248.7 mg catechin equivalents/g DW, respectively. The antioxidant capacities of KRPBE measured using ABTS, DPPH, and ORAC assays were 697.3, 521.8, and 2,627.7 mg vitamin C equivalents/g DW, respectively. KRPBE and its identified phenolics protected against $H_2O_2$-induced oxidative cell death in a dose-dependent manner. Acetylcholinesterase and butyrylcholinesterase, which degrade the neurotransmitter acetylcholine to terminate neurotransmission in synaptic clefts, were inhibited by treatment with KRPBE and its identified phenolics. Taken together, these results suggest that KRPBE and its constituent antioxidative phenolics are potent neuroprotective agents that can maintain cell viability under oxidative stress and inhibit cholinesterase activity.

• The Korea Journal of Herbology
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• v.31 no.3
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• pp.49-57
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• 2016

Objectives： Polygonati Rhizoma (PR) has containing the bioactive compounds such as poly sccharide A,B,C, oligosaccharide, amino acid, it has reported to anti-diabetes and hypertension, atherosclerosis. In this study, we were evaluates antioxidant and anti-physical fatigue effects of PR and steamed PR.Methods : The sample was divided into 5 groups-PR0 (PR without steaming process), PR1 (PR with once steaming process), PR3 (PR with third steaming process), PR6 (PR with sixth steaming process), PR9 (PR with ninth steaming process). We measured anti-oxidant activity through contents of polyphenol, flavonoid and DPPH, ABTS free radical scavenging capacity. And, anti-physical fatigue effect was evaluated using the swimming test, and the AMPK protein expressions in soleus muscle.Results ： As a result, polyphenol, flavonoid, DPPH, ABTS free radical scavenging capacity of PR were increased as steaming times. Anti-physical fatigue effects by swimming test, PR0 have significantly increased, but steamed PR groups were decreased. The AMPK protein expressions of PR0 and PR1 groups were increased comparing with PR3, PR6 and PR9. All groups had effects on decreasing TG, creatine in blood serum, but had no effects on TC in blood serum.Conclusions ： In conclusion, PR with 9 steaming process was more excellent than not-processed PR in anti-oxidant effect such as DPPH, ABTS radical scavenging activity and contents of polyphenol, flavonoid, but, not-processed PR increased swimming times than processed PR. These results suggest that processed PR has anti-oxidant effect as steaming times, and not-processed PR may be a novel potential anti-physical fatigue agents than processed PR.

• Journal of Digital Convergence
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• v.16 no.6
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• pp.353-361
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• 2018

RFW and RFE of castor fruit selected as part of the development of natural antimicrobials and antioxidants yielded 15.8% and 18.4% respectively. In the results of measuring the antimicrobial activity through paper disc method, the antimicrobial activity of castor fruits in ethanol extracts appeared. Especially, the activity was excellent in P. aeruginosa and S. aureus, and antimicrobial activity of C. was 1.5mm up to 16 hours. However, the proliferation of C. was observed again after 24 hours. In the MIC experiment results of RFE, S. aureus and P. aeruginosa showed 96% and 93% of antimicrobial activity, respectively. The DPPH radical scavenging activity of RLW and castor leaf ethanol extract showed $1.8{\pm}0.6%$ and $2.1{\pm}0.7%$ free radical scavenging activity at $1000({\mu}g/m{\ell})$. This study is expected to provide basic data for the development of antimicrobial agents and antioxidants using natural products.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.3
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• pp.399-405
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• 1998

This study was carried out to investigate the effects of herb extracts on lipid oxidation and free radical reaction in iron sources reacted with active oxygen species. The catalytic effects of active oxygen on lipid oxidation in oil emulsion tended to show more active in the order of OH, H2O2 and KO2. Herb extracts tended to show a little catalytic effect and active oxygen scavenging ability of herb extracts didn't show. But herb extracts played role as a strong chelating agents to bind iron if Fe2+ ion exist in oil emulsion. The contents of Fe2+ ion and total iron in Salvia miltiorrhiza Bge. and Angelica gigas Nakai were higher than those of Prunus persica Stockes and pinus strobus. The content of asocrbic acid in Pinus strobus showed the highest (26.97ppm) among several herb extracts. Electron donating abilities of Pinus strobus and Salvia miltiorrhiza Bge. were 79.54% and 77.11%, respectively, which were higher contents than those of Prunus persical Stokes and Angelica gigas Nakai. The SOD-like activity of Prunus persca Stokes showed 0.16 optical density (O.D), which means the most strong antioxidant activity among other herb extracts. The nitrite scavening effects tended to be different depending on pH. Pinus strobus and Angelica gigas Nakai showed 99.8% and 98.6% nitrite scavening effects at pH 1.2. And the effects were decreased as pH was increased. Especially, they didn't show the nitrite scavenging effect in pH 6.0. In conculsin, the Prinus strobus extract among herb extracts were the most effective antioxidant by evaluating several functional tests.

• Molecular & Cellular Toxicology
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• v.5 no.1
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• pp.51-57
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• 2009

Quantum Dot (QD) nanoparticles are used in various industrial applications, such as diagnostic, drug delivery, and imaging agents of biomedicine. Although QDs are extensively used in many medical science, several studies have been demonstrated the potential toxicity of nanoparticles. The first objective of this study was to investigate the nanotoxicity of QDs in the HaCaT human keratinocyte cell line by focusing on gene expression pattern. In order to evaluate the effect of QDs on gene expression profile in HaCaT cells, we analyzed the differential genes which related to oxidative stress and antioxidant defense mechanisms by using human cDNA microarray and PCR array. A human cDNA microarray was clone set, which was sorted for a list of genes correlated with cell mechanisms. We tried to confirm results of cDNA microarray by using PCR array, which is pathway-focused gene expression profiling technology using Real-Time PCR. Although we could not find the exactly same genes in both methods, we have screened the effects of QDs on global gene expression profiles in human skin cells. In addition, our results show that QD treatment somehow regulates cellular pathways of oxidative stress and antioxidant defense mechanisms. Therefore, we suggest that this study can enlarge our knowledge of the transcriptional profile and identify new candidate biomarker genes to evaluate the toxicity of nanotoxicology.

• Korean journal of food and cookery science
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• v.24 no.3
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• pp.349-357
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• 2008

In an effort to augment extractability of carnosine and anserine at the levels of pro-oxidants such as iron and protein in Tuna boiled extracts(Skipjack, Yellowfin and Bigeye), we assessed the effects of heated and ion exchange chromatography(IEC) and ultrafiltration(UF) using a MW 500 cut-off(500 MWCO). We also evaluated the antioxidant activity of these extracts processed as free radical scavengers and reducing agents. Tuna boiled extracts of dark and ordinary muscle protein and total iron were reduced, whereas carnosine and anserine concentrations and antioxidant activity were increased. The carnosine and anserine concentrations of the ion exchange and permeate UF(IEC-UF) extracts were higher than those observed in the heated and permeate UF(heat-UF), whereas the protein and total iron contents were lower than that observed in the heat-UF. The quantity of carnosine and anserine in ordinary muscle was higher than that detected in dark muscle. HPLC analysis and SDS-PAGE were shown to removes the effect of UF on high molecular weight impurities in the tuna boiled extracts. The major free amino acids(FFAs) from Skipjack, Yellowfin and Bigeye tuna IEC-UF extracts were anserine, histidine and carnosine. These three peptides constituted more than 80～85%. of the detected amino acid. The IEC-UF treated ordinary muscle extracts evidenced the highest levels of DPPH radical scavenging activity and the highest levels of reducing power among the various extracts. The IEC-UF extracts evidenced a DPPH radical scavenging effect equal to that of 1mM ascorbic acid.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.132-137
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• 2003

Antioxidant and anti-inflammatory potentials of various grape extracts were evaluated. Extracts from Kyho seed, Kyho stem, and Campbell seed showed potent 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activities compared to resveratrol $(IC_{50}=16.9,\;21.5,\;21.9,\;34.6\;{\mu}g/mL,\;respectively)$, among which, antioxidant effect of Kyho seed extract were similar to that of vitamin C $(IC_{50}=12.2\;{\mu}g/mL)$. These extracts also exhibited inhibitory activities on lipopolysaccharide (LPS)-induced prostaglandin $E_2$ production and nitrite formation in mouse macrophage RAW 264.7 cells at $50\;{\mu}g/mL$. Kyho stem and seed extracts showed growth inhibitory activities in human lung and colon cancer cells. These results suggest the potential roles of grape extracts as antioxidants and anti-inflammatory agents.

• Korean Journal of Plant Resources
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• v.24 no.2
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• pp.200-207
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• 2011

This study was designed to investigate the possible utilization of Castanopsis cuspidata as a source of antiseptic agents. The leaves of C. cuspidata, extracted by 80% ethanol, were sequentially fractionated with n-hexane, dichloromethane, ethylacetate, and n-butanol. In order to effectively screen for a natural preservative agent, we first investigated the antioxidant activities such as DPPH radical scavenging capacity, superoxide radical scavenging capacity, and xanthine oxidase inhibitory activity of the C. cuspidata ethanol extracts and fraction. Using a screening system, we found that the ethylacetate fraction had the strongest antioxidant activity, which followed a dose-dependent manner. The antimicrobial activities were shown in the ethylacetate fraction of C. cuspidata. Among the five fractions, the ethylacetate fraction showed the highest antimicrobial activities against microorganisms tested, which were Bacillus sublitis, Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, Salmonella enteritidis and Salmonella typhimurium. In addition, leaf extracts of C. cuspidata could be suitable for the development of food preservatives.

• Environmental Mutagens and Carcinogens
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• v.20 no.1
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• pp.7-13
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• 2000

The mechanisms of benzene toxicity is not fully elucidated, although the metabolism of benzene is very well understood. In order to study the mechanism of benzene toxicity, we investigated DNA damage induced by benzene metabolite, 1,2,4-benzenetriol (BT) in HL-60 cells by alkaline comet assay. To investigate the mechanism of cellular DNA damage induced by BT, the cells were treated with antioxidant such as vitamin C, SOD, catalase, and chelating agent such as deferoxamine (DFO), bathocuproinedisulfonic acid (BCDS). BT induced DNA damage in dose-dependent manner at concentration between 10$\mu\textrm{m}$ and 100$\mu\textrm{m}$. The antioxidant vitamin C itself induced DNA damage at higher concentration. The DNA damage induced by BT in HL-60 cells was protected at low concentraiton of vitamin C whereas no protective effect was found at high concentration. In hibitory effect of SOD on DNA damage by BT was observed and this suggested that BT produce superoxide anion (O2-) causing DNA damage. Catalase protected BT-induced DNA damage suggesting that BT produce H2O2 during autooxidation of BT. Both Fe(II)-specific cheiating agent, deferoxamine (DFO) and Cu(I)-specific chelating agent, bathocuproinedisulfonic acid (BCDS) inhibited BT0induced DNA damage. This suggested that DNA damage was caused by active species which was produced DAN damage. This suggested that DNA damage was caused by active species which was produced by the autooxidation of BT in the presence of Cu(II) and Fe(III). These findings suggest that reactive oxygen species play an important role in the mechanism of toxicity induced by benzene metabolites.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2002.05a
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• pp.25-35
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• 2002

Transcription factor Nrf2 is essential for the antioxidant responsive element (ARE)-mediated induction of phase II detoxifying and oxidative stress enzyme genes. Detailed analysis of differential Nrf2 activity displayed in transfected cell lines ultimately led to the identification of a new protein, which we named Keap1, that suppresses Nrf2 transcriptional activity by specific binding to its evolutionarily conserved amino-terminal regulatory domain. The closest homolog of Keap1 is a Drosophila actin-binding protein called Kelch, implying that Keap1 might be a Nrf2 cytoplasmic effector. We then showed that electrophilic agents antagonize Keap1 inhibition of Nrf2 activity in vivo, allowing Nrf2 to traverse from the cytoplasm to the nucleus and potentiate the ARE response. We postulate that Keap1 and Nrf2 constitute a crucial cellular sensor for oxidative stress, and together mediate a key step in the signaling pathway that leads to transcriptional activation by this novel Nrf2 nuclear shuttling mechanism. The activation of Nrf2 leads in turn to the induction of phase II enzyme and antioxidative stress genes in response to electrophiles and reactive oxygen species.