• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.4
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• pp.672-678
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• 2002

Oxidative stress contributes to cellular injury following clinical and experimental ischemia/reperfusion scenarios. Oxidative injury can induce cellular and nuclear damages that result in apoptotic cell death. We tested the hypothesis that the catechin flavonoid of (-)epigallocatechin gallate, a green tea polyphenol, inhibits hydrogen peroxide ($H_2O$$_2$)-induced apoptosis in human umbilical vein endothelial cells. The effect of apigenin, a flavone found in citrus fruits, on apoptosis parameters was also examined. A 30 min pulse treatment with 0.25 mM $H_2O$$_2$ decreased endothelial cell viability within 24 hrs by > 30% ; this was associated with nuclear condensation and biochemical DNA damage consistent with programmed cell death. In the 0.25 mM $H_2O$$_2$apoptosis model, 50${\mu}{\textrm}{m}$ (-)epigallocatechin gallate markedly increased cell viability with a reduction in the nuclear condensation and DNA fragmentation. In contrast, equimicromolar apigenin increased cell loss with intense DNA laddering, positive nick-end labeling and Hoechst 33258 staining. Thus, polyphenolic (-)epigallocatechin gallate, but not apigenin flavone, qualify as an antioxidant in apoptosis models caused by oxidative stress. Further work is necessary for elucidating the anti-apoptotic mechanisms of polyphenolic catechins.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.34 no.2
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• pp.129-135
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• 2008

In this study, the potential anti-aging properties of Prunella vulgaris extract were investigated. According to our results, Prunella vulgaris extract increased collagen synthesis(74.7% at 250 ${\mu}g/mL$) and decreased on MMP-1 synthesis(90.2% at 200 ${\mu}g/mL$) and elastase activity(43.7% at 2.0%). Furthermore, it also showed free radical scavenging activity(76.9% at 2.0%) and reduced $H_2O_2$-induced cytoxicity(49.9% at 2.0%). A double-blind clinical study to investigate the effect of Prunella vulgaris extract on the skin's surface was conducted with 22 healthy volunteers, aged 34 to 48 years. The volunteers applied a cream formula with 4.0% of Prunella vulgaris extract, or placebo cream, on each crow's feet twice a day for 12 weeks. Skin wrinkles were evaluated with the naked eye and instrumental image analysis of silicone replicas, followed by statistical analysis. Twelve weeks after application of cream formula with 4.0% of Prunella vulgaris extract, we found significant improvement of facial wrinkle. Moreover, silicone replica analysis confirmed notable improvement in average of R2 and R3 at 12 weeks(p<0.05). These results demonstrate that Prunella vulgaris provides a remarkable and significant tensor and anti-wrinkle effect on the skin, which could be of great use in anti-aging skin care products.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.34 no.4
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• pp.275-286
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• 2008

In this study, we investigated the anti-oxidative, anti-wrinkle and whitening effects of Platycarya strobilacea bark extracts. The free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activity ($FSC_{50}$) of extract / fractions of Platycarya strobilacea was in the order: 50% ethanol extract ($6.75{\mu}g/mL$) < deglycosylated aglycone fraction ($6.62{\mu}g/mL$) < ethyl acetate fraction ($4.15{\mu}g/mL$). Reactive oxygen species (ROS) scavenging activities ($OSC_{50}$) of some Platycarya strobilacea extracts on ROS generated in $Fe^{3+}$-EDTA/$H_2O_2$ system were investigated using the luminol-dependent chemiluminescence assay. The order of ROS scavenging activity was ethyl acetate fraction (OSC50, $0.56{\mu}g/mL$) < 50% ethanol extract ($0.02{\mu}g/mL$) < deglycosylated aglycone fraction ($0.01{\mu}g/mL$). The deglycosylated aglycone fraction showed the most prominent scavenging activity. The protective effects of extract / fractions of Platycarya strobilacea on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The ethanol extract (50%) suppressed photohemolysis in a concentration dependent manner, particularly ethyl acetate fraction exhibited the most prominent cellular protective effect (${\tau}_{50}$, 717.27 min at $10{\mu}g/mL$). The inhibitory effect of Platycarya strobilacea extracts on tyrosinase were investigated to assess their whitening efficacy. Finally, their anti-elastase activities were measured to predict the anti-wrinkle efficacy in the human skin. The inhibitory effect ($IC_{50}$) on tyrosinase of some Platycarya strobilacea extracts was 50% ethanol extract ($243.98{\mu}g/mL$) < ethyl acetate fraction ($153.87{\mu}g/mL$) < deglycosylated aglycone fraction ($137.53{\mu}g/mL$). Also, The inhibitory effect of elastase ($IC_{50}$) of some Platycarya strobilacea extracts was 50% ethanol extract ($31.01{\mu}g/mL$) < ethyl acetate fraction ($14.42{\mu}g/mL$) < deglycosylated aglycone fraction ($1.48{\mu}g/mL$). The cream containing the ethyl acetate fraction of Platycarya strobilacea extracts was formulated. The skin hydration, transepidermal water loss, and the whitening effects were investigated after topical application of the cream. The skin hydration of cream containing extract was increased by $2{\sim}8%$ than the placebo cream, transepidermal water loss was decreased. The cream containing extract suppressed the melanogenesis of skin by 9.55% than the placebo cream. These results indicate that extract / fractions of Platycarya strobilacea can function as antioxidants in biological systems, particularly skin exposed to UV radiation by anti-oxidative activity and protect cellular membranes against ROS. The inhibitory effect on elastase and tyrosinase, and the increase of skin hydration and the whitening effect of the cream containing extract could be applicable to new functional cosmetics for antiaging.

• Microbiology and Biotechnology Letters
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• v.38 no.4
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• pp.405-413
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• 2010

Fig (Ficus carica L.) belongs to the mulberry tree (Moraceae) which is one of the oldest fruits in the world. It has been used as a digestion promoter and a cure for ulcerative inflammation and eruption in Korea. The present study investigated the antimicrobial activity of methanol (MeOH) extract of fig leaves against methicillin-resistant Staphylococcus aureus (MRSA) isolated in clinic. The MeOH extract (MICs, 2.5 to 20 mg/mL; MBCs, 5 to 20 mg/mL) was demonstrated as antibacterial activity in isolates MRSA 1-20. The administration of the MeOH extract in combination with oxacillin or ampicillin induced a reduction of ${\geq}$4-8-fold in all tested bacteria, which was considered to be synergistic based on a FICI of ${\leq}$0.375-0.5. Furthermore, time-kill study was found that a combination of MeOH extract with oxacillin or ampicillin produced a more rapid decrease in the concentration of bacteria CFU/mL than MeOH extract alone. The results suggest that fig leaves could be employed as a natural antibacterial agent in MRSA infection care products.

• Microbiology and Biotechnology Letters
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• v.40 no.3
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• pp.208-214
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• 2012

Chaff-vinegar is known for having a variety of useful purposes in the fields of health and lifestyles. In a previous study we isolated and identified the active fractions of the polyphenol compound 7 species as a potential biomaterial for cosmeceuticals. To further test for its potential use as a functional material, we carried out an MTT assay, collagenase inhibition assay, elastase inhibition assay, tyrosinase inhibition assay, DPPH free radical scavenging assay, SOD-like activity assay and a xanthine oxidase inhibition assay. Chaff-vinegar exhibited potent collagenase and elastase inhibitory activities in a concentration dependent manner, indicating that the agent has the potential to alleviate the skin wrinkling process. Chaff-vinegar also showed 80% tyrosinase inhibition at a concentration of $100{\mu}L/mL$. DPPH radical scavenging, xanthine oxidase inhibition, and SOD-like activity results for each activity were 80%, 80%, and 100%, respectively. Taken together, the present study suggests that chaff-vinegar is a good candidate for use as an anti-wrinkling and/or whitening agent.

• Applied Chemistry for Engineering
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• v.24 no.5
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• pp.483-488
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• 2013

In this study, the cellular protective effect of resveratrol on oxidative damage and its antioxidative activity were investigated. The free radical-scavenging activity ($FSC_{50}$) of resveratrol was measured to be $103{\mu}M$. The reactive oxygen species-scavenging activity ($OSC_{50}$) of resveratrol on the ROS generated in a $Fe^{3+}-EDTA/H_2O_2$ system was investigated using the luminol-dependent chemiluminescence assay. Resveratrol displayed $0.042{\mu}M$ ROS scavenging activity, which is 9.6-fold higher than that of L-ascorbic acid ($0.405{\mu}M$) and had a more prominent cellular protective effect than (+)-${\alpha}$-tocopherol. When HaCaT cells were exposed to $800mJ/cm^2$ of UVB or treated with $30{\mu}M$ rose bengal, resveratrol protected the cells against oxidative stress in a concentration-dependent manner; however, it was unable to protect the cells when the damage was induced by 10 mM $H_2O_2$. These results indicate that resveratrol could be employed to improve and prevent the skin aging through its antioxidative and cellular protective activities.

• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.974-978
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• 2004

Brown-alga-derived natural agent NX42, mainly composed of algal polysaccharides and phlorotannins, showed mild but dose-dependent inhibition of acetylcholinesterase with $IC_{50}=600-700\;{\mu}g/mL$. Phlorotannin-rich fraction of NX42 showed substantial increase of the activity by more than one order of magnitude ($IC_{50}=54\;{\mu}g/mL$) and significant protection of SK-N-SH cells from oxidative stress by $H_2O_2$. Learning trials of mice for 5 consecutive days revealed electric-shock treatment during learning period significantly retarded learning process, whereas NX42-treated mice showed significant resistance against leaning deficiency possibly mainly due to anticholinesterase and neuroprotective activities of phlorotannin.

• Asia Marketing Journal
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• v.6 no.3
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• pp.83-98
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• 2004

The objective of HyundaiCard is to study its differentiated marketing strategy based on consumer lifestyle. HyundaiCard M as late follower in card market must do creative strategy to catch-up pioneer and early follower. But existing HyundaiCard M has a few problems that are its weak service package, marketing communication, less efficient channel, and low brand awareness. To cover these strategic problems this company formulated "M" remarketing strategy and implemented these tactics: segmenting customer based on lifestyle and doing alphabet marketing. Alphabet marketing means differentiated marketing named S, T, U, A, K based on consumer lifestyle.

• Proceedings of the Korean Magnestics Society Conference
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• 1996.05a
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• pp.30-31
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• 1996

• Journal of the Korea Society for Simulation
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• v.20 no.4
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• pp.167-175
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• 2011

Concerning the effectiveness of command and control is increasing worldwide as future warfare is changing into Network Centric Warfare (NCW). Unlike the old attrition warfare that depends mainly on mobility and strike assets, the modern warfare is based on information and network which regards acquisition and circulation of information as important. Therefore, there's no room for rediscussion that C4ISR (Command, Control, Communications, Computers, Intelligence, Surveillance and Reconnaissance) system will play an important role in warfare. In spite of this fact, there isn't any way to explain clearly how to measure the effectiveness of command and control system in a battle and to reflect it systematically in a system effectiveness. In this study, we examined NCO-CF (Network Centric Operations-Conceptual Framework), developed by the Department of Defense (DOD), which can conceptually explain the increment of effectiveness of C4ISR system that is the basis of NCO. And we suggested methodology based on NCO-CF to establish the evaluation criteria for M&S analysis of command and control effectiveness. As a case study we derived the evaluation criteria for the command and control system in joint operations by applying the suggested methodology.