• 약학회지
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• 제52권2호
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• pp.117-124
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• 2008

The leaves of Perilla frutescens Britt. var. japonica Hara (Labiatae) are often used in gourmet food in several Asian countries. Two kinds of perilla cultivars, Namcheon (NC) and Bora (BR), have been respectively developed in Korea by the pure line of 'deulkkae' from the local variety and by the cross of 'deulkkae' and 'chajogi'. The present study evaluated and compared antioxidant and neuroprotective effects of the fractions prepared from the leaves of the two cultivars using cell-free bioassay systems and primary cultured rat cortical cells. We found that the spirit, chloroform, hexane and butanol fractions from NC and BR leaves inhibited lipid peroxidation initiated in rat brain homogenates by $Fe^{2+}$ and L-ascorbic acid. In contrast, only the spirit and butanol fractions from both cultivars exhibited 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity. Among the fractions tested, the butanol fractions from NC and BR leaves exhibited the most potent antioxidant properties, and the butanol fraction from BR was more potent than the NC fraction. In consistence with these findings, the butanol fractions from both cultivars protected primary cultured cortical cells from the oxidative damage induced by $H_2O_2$ or xanthine and xanthine oxidase, with the BR butanol fraction being more active. The butanol fractions from NC and BR did not produce cytotoxicity in our cultures treated for 24 h at the concentrations of up to $100\;{\mu}g/ml$. Taken together, these results indicate that the leaves of the two cultivars of Perilla frutescens exert antioxidant and neuroprotective effects, and that the butanol fraction from BR leaves exhibits the most potent antioxidative neuroprotection among the fractions tested in this study.

• 한국군사과학기술학회지
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• 제11권4호
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• pp.133-140
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• 2008

The purpose of this study is to provide response methods to minimize the damage from chemical terrorism in a naturally ventilated indoor system using several types of dispersion simulations. Three chemical warfare agents such as sarin(GB), phosgene and chlorine gas which have high potential to be used in terror or to be involved with accidents were selected in this simulation. Fire dynamic simulation based on Large Eddy Simulation which is effective because of less computational effort and detailed expression of the dispersion flow was adopted to describe the dispersion behavior of these agents. When the vent speed is 0.005m/s, the heights of 0.1 agent mass fraction are 0.9m for sarin, 1.0m for phosgene and 1.1m for chlorine gas, and the maximum mass fraction are 0.27 for all three agents. However, when the vent speed is increased to 0.05m/s, the heights of 0.1 agent mass fraction become 1.6m for all three agents and maximum mass fraction inside the room increase to 0.70 for sarin, 0.58 for phosgene and 0.53 for chlorine gas. It is shown that molecular weight of the agents has an important role for dispersion, and it is important to install ventilation system with height less than 1.6m to minimize the damage from chemical toxicity.

• Journal of Applied Biological Chemistry
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• 제63권4호
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• pp.357-363
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• 2020

Oxidative stress caused by the overproduction of reactive oxygen species (ROS) is known as an etiology of neurodegenerative diseases. Populus tomentiglandulosa (PT), a member of the Salicaceae family, is widely grown in Korea and has been reported to exert protective effects on cerebral ischemia by attenuating of oxidative stress and neuronal damage. In the present study, we investigated the antioxidant activity and neuroprotective effects of an ethanol extract and four fractions [n-butanol, ethyl acetate (EtOAc), chloroform, and n-hexane] of PT under in vitro and cellular systems. The extract and four fractions of PT showed 1,1-diphenyl-2-picrylhydrazyl (DPPH), •OH, and O2- radical scavenging activities in a dose-dependent manner. In particular, the EtOAc fraction of PT had the strongest DPPH, •OH, and O2- radical scavenging activities among the extract and other fractions. Therefore, we further investigated the neuroprotective effect of the EtOAc fraction of PT against oxidative stress in H2O2-induced SH-SY5Y cells. Treatment with H2O2 significantly decreased cell viability and lactate dehydrogenase (LDH) release, and it also increased the ROS levels compared to the normal group. However, treatment with the EtOAc fraction of PT significantly increased cell viability. Moreover, the EtOAc fraction of PT-treated group significantly suppressed ROS production and LDH release compared to the H2O2-induced control group. In conclusion, our findings indicated that PT had in vitro antioxidant activity and neuroprotective effects against oxidative stress. Therefore, PT could be used as a natural agent for protection against oxidative stress.

• 공업화학
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• 제29권6호
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• pp.772-781
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• 2018

본 연구에서는 범부채 뿌리 50% 에탄올 추출물 및 에틸아세테이트 분획물을 제조하고 이들의 항산화 및 항균 활성, 세포 보호 효능을 평가하였다. 1,1-Diphenyl-2-picrylhydrazyl (DPPH) 자유라디칼 소거 활성($FSC_{50}$) 측정 결과, 50% 에탄올 추출물은 $621.5{\mu}g/mL$, 에틸아세테이트 분획물은 $253.0{\mu}g/mL$이었다. Luminol 발광법을 이용한 총 항산화능($OSC_{50}$)은 추출물과 분획물에서 각각 13.6 및 $3.0{\mu}g/mL$이었다. 항균 활성 측정에서 Staphylococcus aureus 및 Candida albicans에 대한 에틸아세테이트 분획물의 최소저해농도(minimum inhibitory concentration, MIC)는 각각 156 및 $1,250{\mu}g/mL$으로 나타났으며, 화장품에 사용하는 기존 방부제인 methyl paraben보다 유사하거나 더 높은 활성을 보여주었다. $^1O_2$로 유도된 세포 손상에 대한 보호 효과(${\tau}_{50}$)에서 50% 에탄올 추출물은 $4{\sim}64{\mu}g/mL$ 농도 범위에서 농도 의존적으로 세포 보호 활성을 나타냈다. $16{\mu}g/mL$ 농도에서 50% 에탄올 추출물, 에틸아세테이트 분획물 및 (+)-${\alpha}$-tocopherol의 ${\tau}_{50}$은 각각 36.4, 45.0 및 45.8 min이었으며, 에틸아세테이트 분획물은 $^1O_2$로 유도된 세포 손상에서 (+)-${\alpha}$-tocopherol과 유사한 세포 보호 활성을 나타냈다. UVB로 유도된 HaCaT 세포 손상에서 에틸아세테이트 분획물은 $8{\mu}g/mL$에서 세포 내 활성산소종(reactive oxygen species, ROS)을 최대 45.9%까지 감소시켰다. 과산화수소로 유도된 HaCaT 세포 손상에서도 에틸아세테이트 분획물은 $0.5{\sim}8.0{\mu}g/mL$에서 세포 생존율을 유의적으로 증가시켰다. 범부채 뿌리 에틸아세테이트 분획물의 성분 분석 결과, irisflorentin, irigenin, tectorigenin, resveratrol, iridin 및 tectoridin 등의 플라보노이드 및 폴리페놀 성분이 확인되었다. 결론적으로 범부채 뿌리 추출물 및 분획물은 화장품의 천연 항산화 및 항균 소재로서 적용 가능성이 있음을 시사한다.

• 대한수의학회지
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• 제34권2호
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• pp.249-258
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• 1994

This study was carried out to investigate the inhibitory effects of vitamin E on the oxidative damage of cellular lipids and proteins in free radical reaction induced by $FeCl_3$, and ascorbic acid. In this experiment, a vitamin E treated rat group was administered with 100mg/kg body weight of $dl-{\alpha}-tocophery$ 1 acetate and an untreated rat group was administered with the same volume of corn oil. And then assays of malondialdehyde and carbonyl group in total homogenate, mitochondrial and microsomal fraction of rat liver were carried out at the scheduled time. The results obtained from this study were summarized as follows; 1. Lipid peroxidation levels in vitamin E administered rat liver cells were significantly (p<0.05) decreased at the intervals between 1 hour and 4 hours in liver homogenate, at all times except for 1 hour point in mitochondrial fraction, and also at the intervals between 0.5 hour and 3 hours in microsomal fraction compared with those of the control rat liver cell. 2. Protein oxidation levels in vitamin E administered rat liver cell were also significantly (p<0.05) decreased at the intervals between 1.5 hours and 4 hours in liver homogenate, at over 4 hours in liver mitochondrial fraction, and at the intervals between 0.5 hour and 3 hours in liver microsomal fraction compared with those of the control rat liver cells.

• Smart Structures and Systems
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• 제23권2호
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• pp.173-184
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• 2019

The main objective of this study is to evaluate the true fracture energy and monitor the damage progression in steel fibre reinforced concrete (SFRC) specimens using acoustic emission (AE) features. Four point bending test is carried out using pre-notched plain and fibre reinforced (0.5% and 1% volume fraction) - concrete under monotonic loading. AE sensors are affixed at different locations of the specimens and AE parameters such as rise time, AE energy, hits, counts, amplitude and duration etc. are obtained. Using the captured and processed AE event data, fracture process zone is identified and the true fracture energy is evaluated. The AE data is also employed for tracing the damage progression in plain and fibre reinforced concrete, using both parametric- and signal- based techniques. Hilbert - Huang transform (HHT) is used in signal based processing for evaluating instantaneous frequency of the acoustic events. It is found that the appropriately processed and carefully analyzed acoustic data is capable of providing vital information on progression of damage on different types of concrete.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2001년도 춘계학술발표대회 논문집
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• pp.89-92
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• 2001

Drop weight impact tests were performed to investigate the impact behavior of carbon fiber/epoxy composite laminates reinforced by short fibers and other interleaving materials. Characterization techniques, such as cross-sectional fractography and scanning acoustic microscopy, were employed quantitatively to assess the internal damage of some composite laminates. Scanning electron microscopy was used to observe impact damage and fracture modes on specimen fracture surfaces. The results show that composite laminates experience various types of fracture; delamination, intra-ply cracking, matrix cracking and fiber breakage depending on the interlayer materials. Among the composite laminates tested in this study, the composites reinforced by Zylon fibers showed very good impact damage resistance with medium level of damage, while the composites interleaved by poly(ethylene-co-acrylic acid) (PEEA) film is expected to deteriorate the bulk strength due to the reduction of fiber volume fraction, even though the damaged area is significantly reduced.

• 한국식품과학회지
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• 제32권2호
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• pp.461-468
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• 2000

본 연구에서는 Comet assay를 이용해서 차 및 전통 약재로 사용하고 있는 한국산 겨우살이의 항유전독성을 측정하고자 하였다. 겨우살이 조추출물을 분자량에 따라 14,000 이상 분획(I), $8,000{\sim}14,000$의 분획(II), $3,500{\sim}8,000$ 분획(III) 그리고 3,500 이하 분획(IV)으로 분리하였다. 이중 분획 IV만이 비종양성 3T3 세포에서 농도에 따른 MNNG에 의한 DNA 손상을 감소시켰으며 겨우살이 lectin과 viscotoxin이 포함된 분획 I, III은 활성을 전혀 나타내지 않았다. 열처리에 의해서도 분획 IV는 시간이 지남에 따라서 활성이 약간 감소됨을 나타내었으나 여전히 유의적인 효과를 지니고 있었다. 겨우살이 분획 IV로부터 얻어진 유기용매 분획의 항유전독성 평가결과, 분획 IV의 항유전독성은 주로 수용성 물질에 의해 나타나는 것임을 알 수 있었다. Sephadex G-25 gel filtration chromatography에서, 겨우살이 분획 IV의 항유전독성에 기여하는 성분은 분자량 1,000 미만의 수용성 물질이었으며 이 저분자량 물질을 분리해내어 암 예방을 위한 기능성 식품소재로써 이용할 수 있는 가능성을 확인할 수 있었다.

• 한국식품저장유통학회:학술대회논문집
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• 한국식품저장유통학회 2003년도 춘계총회 및 제22차 학술발표회
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• pp.109.2-110
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• 2003

The neuroprotective effect of solvent fraction of native edible plant MK-104 in the mice administered with kainate was evaluated using behavioral sign, neuronal injuries and biomarkers of oxidative stress. Mice, ICR male, were administered with the BFME through a gavage for 4 days consecutively, and on the 3rd day, kainate (450 mg/kg) was i.p. administered. The fraction(400 mg/kg) delayed the onset time of neurobehavioral change (p<0.01), reduced the severity of convulsion and lethality (p<0.05), and restored the level of GSH and lipid peroxidation in brain to control value. A similar protective action was also expressed by fraction-I (200 mg/kg), which showed a prominent protection against the neuronal damage in hippocampal CA1 and CA2 regions (p<0.01) caused by kainate injection. of TBARS value. Based on these results, BFME-I is suggested to contain a functional agent to prevent against oxidative stress in the brain of mice.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.205.1-205.1
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• 2003

Several lines of recent evidences have shown that several pro-inflammatory genes or mediators, such as inducible nitric oxide synthase (iNOS)are strongly expressed in the ischemic brain. Inflammation is now recognized as a significant contributing mechanism in cerebral ischemia because anti-inflammatory compounds or inhibitors of iNOS have been proven to reduce ischemic brain damage. In iNOS assay, hexane fraction of M61 inhibited NO (iNOS IC50, 0.7${\mu}$g/ml). In vivo study was carried out to evaluate neuroprotective effect of hexane fraction of M61 after transient global ischemia using Mongolian gerbil ischemia model. (omitted)