• Advanced Composite Materials
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• 제16권4호
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• pp.315-334
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• 2007

In the present study, chopped henequen natural fibers without and with surface modification by electron beam (E-beam) treatment were incorporated into a polypropylene matrix. Prior to composite fabrication, a bundle of raw henequen fibers were treated at various E-beam intensities from 10 kGy to 500 kGy. The effect of E-beam intensity on the interfacial, mechanical and thermal properties of randomly oriented henequen/polypropylene composites with the fiber contents of 40 vol% was investigated focusing on the interfacial shear strength, flexural and tensile properties, dynamic mechanical properties, thermal stability, and fracture behavior. Each characteristic of the material strongly depended on the E-beam intensity irradiated, showing an increasing or decreasing effect. The present study demonstrates that henequen fiber surfaces can be modified successfully with an appropriate dosage of electron beam and use of a low E-beam intensity of 10 kGy results in the improvement of the interfacial properties, flexural properties, tensile properties, dynamic mechanical properties and thermal stability of henequen/polypropylene composites.

• 한국유기농업학회지
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• 제32권1호
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• pp.91-105
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• 2024

본 연구에서는 페놀 화합물, 라디칼 소거능, 환원능력 분석 및 세포 내 ROS 측정을 통해 질경이 추출물의 항산화 능력을 확인하였다. 질경이 추출물의 총 폴리페놀 및 플라보노이드함량은 각각 50.91±0.78 mg GAE/g, 100.99±0.44 mg rutin/g으로 나타났으며, DPPH 및 ABTS radical 소거능과 환원력 모두 농도 의존적으로 증가하였다. 또한, 세포 내 ROS는 질경이 추출물에 의해 생성이 억제됨을 확인하였다. 항염증 활성은 RAW 264.7 세포를 이용하여 염증을 유도한 뒤 NO 측정과 western blot 분석을 통해 염증성 단백질 발현량을 확인하였다. 질경이 추출물은 LPS를 처리한 RAW 264.7 세포에서 NF-ĸB의 신호 전달 경로를 억제하여 염증성 단백질인 iNOS 및 COX-2의 발현량을 조절하였으며, 이로 인해 NO의 생성량을 억제하였다. 본 실험 결과를 통해 질경이 추출물의 항산화 및 항염증에 대한 우수한 활성을 확인하였으며, 식의약품 분야를 비롯한 농산업 분야에서 다양한 기능성 천연 소재로 활용될 수 있을 것으로 기대된다.

• Carbon letters
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• 제9권4호
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• pp.298-302
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• 2008

Carbon blacks could be used as the filler for the electromagnetic interference (EMI) shielding. The poly vinyl alcohol (PVA) and polyvinylidene fluoride (PVDF) were used as the matrix for the carbon black fillers. Porous carbon blacks were prepared by $CO_2$ activation. The activation was performed by treating the carbon blacks in $CO_2$ to different degrees of burnoff. During the activation, the enlargement of pore diameters, and development of microporous and mesoporous structures were introduced in the carbon blacks, resulting in an increase of extremely large specific surface areas. The porosity of carbon blacks was an increasing function of the degree of burn-off. The surface area increased from $80\;m^2/g$ to $1142\;m^2/g$ and the total pore volume increased from $0.14073\;cc{\cdot}g^{-1}$ to $0.9343\;cc{\cdot}g^{-1}$. Also, the C=O functional group characterized by aldehydes, ketones, carboxylic acids and esters was enhanced during the activation process. The EMI shielding effectiveness (SE) of raw N330 carbon blacks filled with PVA was about 1 dB and those of the activated carbon blacks increased to the values between 6 and 9 dB. The EMI SE of raw N330 carbon blacks filled with PVDF was about 7 dB and the EMI SE increased to the range from 11 to 15 dB by the activation.

• 생약학회지
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• 제43권2호
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• pp.173-178
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• 2012

In this study, we investigated antibacterial activity and nitric oxide production inhibitory effect of the methanol extract and its fractions from Paeoniae Radix. In antibacterial activity by the disc diffusion assay against S. aureus, S. epidermidis and P. aeruginosa, the ethyl acetate fraction showed stronger antibacterial activity than other fractions and the extract. Moreover, the ethyl acetate fraction showed strong nitric oxide (NO) production inhibitory effect in lipopolysaccharide (LPS)-stimulated RAW 264.7 cell. However, in NO scavenging ability, the chloroform fraction was higher than the other fractions and the extract. In the lactate dehydrogenase (LDH) assay against RAW 264.7 cell, the extract and fractions were exhibited normal LDH release level as nontoxic result without the ehtyl acetate fraction of 100 ${\mu}g/ml$. As a result, the ethyl acetate fraction and chloroform fraction of the methanol extract from Paeoniae Radix could be applicable to functional materials for antibacterial and anti-inflammatory related fields, respectively.

• 한국식품영양학회지
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• 제33권5호
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• pp.483-492
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• 2020

This study provides data to explore functional medicinal food materials that can prevent adult diseases, and verified antioxidant and anti-inflammatory of each solvent fraction of the methanol extract of Salvia plebeia R. Br. in Korea. In the analysis of total phenol content, DPPH radical scavenging ability, and FRAP reduction ability as indicators of antioxidant activity, the methanol fraction and ethyl acetate fraction of the Salvia plebeia R. Br. group showed high antioxidant activity. Ethyl acetate fraction of Salvia plebeia R. Br. methanol extract also showed excellent antioxidative activity as compared with BHT. In the mouse macrophage line Raw 264.7 cells, the NO production ability by LPS treatment was significantly increased in the LPS treatment group compared to the untreated group. In inflammatory reactions induced by LPS treatment in Raw 264.7 cells, inflammatory cytokines (TNF-α, PGE2, IL-1β) and NO production were decreased in the EtOAc fraction and MeOH fraction of the methanol extract of Salvia plebeia R. Br. compared to the case of LPS treatment alone. The anti-inflammatory effect was proved by significantly inhibiting the production of inflammatory cytokines. The present results suggest that Salvia plebeia R. Br. supplementation is beneficial for the suppression of antioxidant and anti-inflammation.

• Preventive Nutrition and Food Science
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• 제9권3호
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• pp.270-275
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• 2004

Previous studies have shown that kimchi and kimchi-derived 3-(4'-hydroxyl-3', 5'-dimethoxyphenyl) propionic acid have anti-oxidative and hypolipidemic effects in rats and rabbits. This study was designed to investigate whether chemically synthesized 3-(4'-hydroxyl-3', 5' -dimethoxyphenyl) propionic acid (HDMPPA) may ameliorate oxidative stress through the regulation of nuclear factor KB (NFkB) activation in lipopolysaccharide (LPS)-stimulated RAW 264.7 murine macrophage cells. Treatment of RAW 264.7 cells with 400 uM of HDMPPA significantly reduced LPS-stimulated nitric oxide (NO) production. Treatments with HDMPPA at 100 uM to 400 uM concentrations significantly elevated glutathione (GSH) level. However, cell viability and thiobarbituric acid-reactive substances (TBARS) concentrations were not affected by the concentrations of HDMPPA used. The specific DNA binding activities of NFKB, a transcription factor which is sensitive to oxidative stress, were not down-regulated by HDMPPA treatments. These results suggest that HDMPPA may have weak anti-oxidative activity against LPS challenge by scavenging NO and stimulating GSH production.

• Food Science and Biotechnology
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• 제27권6호
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• pp.1761-1769
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• 2018

Enzyme-assisted extraction is a cost-effective, safe, and efficient method to obtain bioactives from plant materials. During this study, 10 different marine algae from Sri Lanka were individually extracted by using five commercial food-grade carbohydrases. The enzymatic and water extracts of the seaweeds were analyzed for their antioxidant and anti-inflammatory activities. The highest DPPH, hydrogen peroxide ($H_2O_2$) and intracellular $H_2O_2$ scavenging abilities were observed from the Celluclast extract of Sargassum polycystum (CSp). CSp exerted protective effects against oxidative stress-induced cell death in hydrogen peroxide-induced Chang cells and in model zebrafish. The Celluclast extract of Chnoospora minima (CCm) showed the strongest anti-inflammatory activity against lipopolysaccharide (LPS)-induced NO production in RAW 264.7 macrophages ($IC_{50}=44.47{\mu}g/mL$) and in model zebrafish. CCm inhibited the levels of iNOS, COX-2, $PGE_2$, and TNF-${\alpha}$ in LPS stimulated RAW 264.7 macrophages. Hence, CSp and CCm could be utilized in developing functional ingredients for foods, and cosmeceuticals.

• 한국해양바이오학회지
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• 제12권1호
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• pp.11-19
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• 2020

This study aims to review the progress of biotechnological applications of sea cucumber and presents fundamental validation data on a range of methods and applications to determine the most promising fields for future exploitation and application. Sea cucumbers from different regions, subjected to numerous industrially applicable drying methods, were evaluated for their biochemical composition. The study highlights the nutritional excellence of Jeju red sea cucumber, particularly the high amino acid and fatty acid composition of its intestinal organs and the possibility of the industrial utilization of these organs. In addition, an efficient extraction method to extract collagen and chondroitin sulfate from red sea cucumber was established. The extracted collagen and chondroitin sulfate can be used as commercially valid biomaterials. Accordingly, the red sea cucumber was confirmed as a valuable source of raw food material of varied functionality and bioactivity. Upon conducting an analysis of patents thus far relating to the sea cucumber, it was found that the associated technology was limited to some parts of primary and secondary industries. Therefore, there is a clear need for the strategic development of technologies to produce specialized functional products from sea cucumber's raw materials, with a view to promote other related industries.

• 동의생리병리학회지
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• 제35권5호
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• pp.169-176
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• 2021

This study was conducted to suggest the Cudrania tricuspidata leaf and Achyranthes japonica Nakai Complex (CAC) possibility of use as a functional natural material for improving bone disease. Cudrania tricuspidata leaf and Achyranthes japonica Nakai were mixed in the same amount, extracted with hot water, and then powdered and used in the study. After, the cytotoxicity of CAC for osteoblasts (MG63 cell), osteoclasts (differentiated RAW264.7 cell), and macrophages (RAW264.7 cell) were evaluated by MTT assay, and ALP assay and TRAP assay were performed to confirm the differentiation capacity of osteoblasts and osteoclasts, respectively. In addition, the anti-inflammatory effect in macrophages was evaluated by ELISA, qRT-PCR, and western blot assay. CAC did not proliferated osteoblasts and osteoclasts, but increased ALP activity against osteoblasts differentiation and decreased TRAP activity against osteoclasts differentiation. CAC did not proliferated macrophages but decreased nitric oxide production. Also, decreased NOS2, IL1B, IL6, PTGS2, and TNFA gene expression, and JNK and p38 protein phosphorylation in a concentration-dependent manner, but ERK protein phosphorylation was not changed. As a result, CAC increased the differentiation and activation of osteoblasts, inhibited the differentiation and activation of osteoclasts, and regulated the expression of inflammatory cytokines in macrophages. Therefore, it is thought that CAC can be used as a functional natural material that prevents bone disease and has an anti-inflammatory effect.

• 한국식품영양학회지
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• 제27권6호
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• pp.1033-1042
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• 2014

본 연구는 한국의 전통발효식초가 지닌 새로운 생물학적 기능을 규명하기 위해 국내 및 국외에서 제조된 전통발효식초로부터 다당류를 분리하여 면역자극활성을 검토하였다. 국내산 현미식초 조다당(KBV-0), 일본산 현미식초 조다당(JBV-0) 및 국내산 감식초 조다당(KPV-0)을 분리하여 구성당 분석한 결과, KBV-0와 JBV-0는 주로 mannan으로 구성되어 있으며, KPV-0는 펙틴 유래 물질로 인한 조성으로 사료되었다. 3종의 다당 시료는 RAW 264.7 세포에 독성을 나타내지 않은 반면, RAW 264.7 세포를 자극하여 IL-6, IL-12 및 TNF-${\alpha}$와 같은 사이토카인의 생성을 농도 의존적인 경향으로 증진시켰으나, 특히 KPV-0의 활성이 KBV-0와 JBV-0보다 더 우수하였다. 또한 KPV-0는 대식세포의 포식작용과 관련있는 FcR II의 발현량을 유일하게 증가시켰다. 이상의 결과로부터 국내산 전통발효 감식초인 KPV-0는 다른 발효식초에 비해 더 우수한 면역활성을 지니는 것으로 나타났으며, 이는 기능성 소재로의 산업적 응용이 가능할 것으로 사료되었다.