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101.
Yasantha Athukorala Ki‐Wan Lee Eun‐Ju Park Moon‐Soo Heo In‐Kyu Yeo Young‐Don Lee You‐Jin Jeon 《Journal of the science of food and agriculture》2005,85(14):2341-2348
The antioxidant activity of an extract of Grateloupia filicina was evaluated using linoleic acid and fish oil as substrates in an induct period at 65 °C. Furthermore, the algal extract was subjected to comet assay to evaluate its protecting ability for H2O2‐induced DNA damage in rat lymphocytes. Progression of oxidation was examined using weight gain, peroxide value (PV), 2‐thiobarbituric acid reactive substances and conjugated diene data. Effectiveness of the extract at 0.03 and 0.05% levels was superior to that of α‐tocopherol at 0.01% and the activity of 0.05% extract was higher than that of butylated hydroxyanisole and butylated hydroxytoluene at 0.01%. Also, the algal extract significantly inhibited H2O2 induced DNA damage in comet assay. The maximum DNA damage inhibition (68.9%) was recorded from the 50 µg ml−1 alga extract when the rat lymphocyte cells were treated with 50 µM H2O2. Copyright © 2005 Society of Chemical Industry 相似文献
102.
Seung-Hong Lee Jung-In Choi Soo-Jin Heo Mi-Hwa Park Pyo-Jam Park Byong-Tae Jeon Se-Kwon Kim Ji-Sook Han You-Jin Jeon 《Food science and biotechnology》2012,21(1):239-246
Pancreatic β cells are very sensitive to oxidative stress and this may play an important role in β cell death in diabetes.
The protective effect of diphlorethohydroxycarmalol (DPHC), one of phlorotannin polyphenol compound purified from pae (Ishige okamurae) against high glucoseinduced oxidative stress was investigated using RINm5F pancreatic β cells. High glucose (30 mM) treatment
induced RINm5F pancreatic β cells cell death, but DPHC, at concentration 10 or 50 μg/mL, significantly inhibited the high
glucose-induced glucotoxicity and apoptosis. Furthermore, treatment with DPHC dose-dependently decreased thiobarbituric acid
reactive substances (TBARS), intracellular reactive oxygen species (ROS) generation and nitric oxide level increased by high
glucose. In addition, DPHC treatment increased activities of antioxidant enzymes including catalase (CAT), superoxide dismutase
(SOD), and glutathione peroxidase (GSH-px) in high glucose pretreated RINm5F pancreatic β cells. DPHC treatment improved the
secretory responsiveness following stimulation with glucose. These findings indicate that DPHC might be used as potential
nutraceutical agent which will protect the glucotoxicity caused by hyperglycemia-induced oxidative stress associated with
diabetes. 相似文献
103.
In order to obtain basic data for the utilisation of Zanthoxylum piperitum leaf as a functional substance in the food industry, the antioxidative and neuronal cell protective effects of silica-gel open column chromatographic fractions, obtained from Z. piperitum leaf, were examined. ABTS and FRAP assays indicated that the ZP4 fraction (eluted with methanol/chloroform, 1:4, v/v) of Z. piperitum leaf was a more potent radical-scavenger and reducing agent than the other five fractions. The ZP4 fraction also presented protective effects against H2O2-induced neurotoxicity in a dose-dependent manner. Therefore, our study verified that the ZP4 fraction has strong antioxidative and neuronal protective effects which are correlated with its high level of phenolics, particularly quercitrin, afzelin, and hyperoside. These phenolics of Z. piperitum leaf can be utilised as effective and safe functional food substances, i.e., natural antioxidants, and may reduce the risk of neurodegenerative disorders. 相似文献
104.
Sâmya Soler Gebara Wellyta de Oliveira Ferreira Nilva Ré-Poppi Euclésio Simionatto Eduardo Carasek 《Food chemistry》2011
Volatile compounds present on fruits and leaves of Mangifera indica var. coquinho were investigated by headspace solid phase microextraction (HS-SPME) and hydrodistillation (HD). Conventional techniques, such as hydrodistillation, may impart chemical changes to the original oil composition being also time-consuming. On the other hand, HS-SPME provides solvent-less extractions, shorter extraction times and may supply complementary information about the composition of the compounds. The HS-SPME technique was previously evaluated by the comparative study among the fibres: commercial PDMS, NiTi-ZrO2 and NiTi-ZrO2-PDMS. The fibre NiTi-ZrO2-PDMS showed better sensitivity and precision and was used on the extraction of components. The influence of several parameters like the time and temperature of extraction and desorption time were examined to obtain better efficiency. Fruits and leaves were analysed in mature and immature stages. The profiles corresponding to the volatile compounds detected by both techniques are discussed. 相似文献
105.
Nanoparticle‐Enhanced Silver‐Nanowire Plasmonic Electrodes for High‐Performance Organic Optoelectronic Devices 下载免费PDF全文
Taehyo Kim Saewon Kang Jungwoo Heo Seungse Cho Jae Won Kim Ayoung Choe Bright Walker Ravi Shanker Hyunhyub Ko Jin Young Kim 《Advanced materials (Deerfield Beach, Fla.)》2018,30(28)
Improved performance in plasmonic organic solar cells (OSCs) and organic light‐emitting diodes (OLEDs) via strong plasmon‐coupling effects generated by aligned silver nanowire (AgNW) transparent electrodes decorated with core–shell silver–silica nanoparticles (Ag@SiO2NPs) is demonstrated. NP‐enhanced plasmonic AgNW (Ag@SiO2NP–AgNW) electrodes enable substantially enhanced radiative emission and light absorption efficiency due to strong hybridized plasmon coupling between localized surface plasmons (LSPs) and propagating surface plasmon polaritons (SPPs) modes, which leads to improved device performance in organic optoelectronic devices (OODs). The discrete dipole approximation (DDA) calculation of the electric field verifies a strongly enhanced plasmon‐coupling effect caused by decorating core–shell Ag@SiO2NPs onto the AgNWs. Notably, an electroluminescence efficiency of 25.33 cd A?1 (at 3.2 V) and a power efficiency of 25.14 lm W?1 (3.0 V) in OLEDs, as well as a power conversion efficiency (PCE) value of 9.19% in OSCs are achieved using hybrid Ag@SiO2NP–AgNW films. These are the highest values reported to date for optoelectronic devices based on AgNW electrodes. This work provides a new design platform to fabricate high‐performance OODs, which can be further explored in various plasmonic and optoelectronic devices. 相似文献
106.
Jong Heo David Lam George H. Sigel Jr. Edgar A. Mendoza David A. Hensley 《Journal of the American Ceramic Society》1992,75(2):277-281
Structural development of tellurite glasses with the addition of Li2 O and Na2 O has been studied using infrared, Raman, and X-ray photoelectron spectroscopies. The increase in intensity of the peak at 755 cm−1 in the infrared spectra as compared to the peak at 620 cm −1 suggests the transformation of TeO4 building units to TeO3 pyramids with the addition of alkali oxide. Proposed structural change is further supported by the strong compositional dependence of the 755-cm−1 peak in the Raman spectra as well as by the formation of a shoulder in the O 1 s peak of X-ray photoelectron spectra. In contrast to alkali silicate glasses, formation of nonbridging oxygens with the addition of alkali oxide is not observed. 相似文献
107.
Chang Hwa Jung Jiyun Ahn Seok Hyun Heo Tae-Youl Ha 《Food science and biotechnology》2014,23(3):889-893
In this study, we investigated the anti-adipogenic effects of Eleutherococcus senticosus and its active compounds in vitro to examine new functions. We first analyzed the active compounds in E. senticosus growing in Korea using HPLC and found that the concentration of eleutheroside B and E was higher in stems and roots than in other plant parts. There were no significant (p<0.05) differences in eleutheroside concentration between plant ages. Anti-adipogenic effects of E. senticosus on lipid accumulation in 3T3-L1 cells were examined. Extracts of stems and roots more effectively inhibited lipid accumulation in 3T3-L1 cells than extracts of other plant parts. Eleutheroside E was responsible for the pharmacological anti-adipogenic effects via regulation of the mTOR pathway. This is the first report of an anti-adipogenic effect of E. senticosus and the active compound eleutheroside E. 相似文献
108.
109.
Impacts of climate and land‐cover changes on water resources in a humid subtropical watershed: a case study from East Texas,USA 下载免费PDF全文
Joonghyeok Heo Jaehyung Yu John R. Giardino Huidae Cho 《Water and Environment Journal》2015,29(1):51-60
This study investigates the response of water resources regarding the climate and land‐cover changes in a humid subtropical watershed during the period 1970–2009. A 0.7°C increase in temperature and a 16.3% increase in precipitation were observed. Temperature had a lower increase trend, and precipitation showed definite increasing trend compared to previous studies. The main trend of land‐cover change was conversion of vegetation and barren lands to developed and crop lands affected by human intervention, and forest and grass to bush/shrub which considered to be caused by natural climate system. Hydrologic responses to climate and land‐cover changes resulted in increases of surface run‐off (15.0%), soil water content (2.7%), evapotranspiration (20.1%) and a decrease in groundwater discharge (9.2%). We found that surface run‐off is relatively stable with precipitation, whereas groundwater discharge and soil water content are sensitive to changes in land cover, especially land cover brought about by human intervention. 相似文献
110.
Young-Sun Heo Jay G. Sanjayan Cheon-Goo Han Min-Cheol Han 《Construction and Building Materials》2011,25(6):2928-2938
In this paper, a construction application of a technique to improve the fire resistance of high strength concrete is presented. Before the construction application, fire tests of three hours duration were carried out in accordance with ISO-834. Three types of mitigating methods, namely, a specimen with no protection (control), with fireproof panel protection and with the combination of polypropylene fibre reinforcement and metal mesh confinement (Fibre/Mesh), were applied to full sized columns for comparison purposes. The fire resistance performance of all columns was tested under loads. After the fire tests, the severity of spalling of specimens was assessed, and the best performing technique, Fibre/Mesh, for spalling protection was selected for an application in practice. The process of the construction application is described in detail, including pumping, pouring and compacting of the concrete. The concrete quality was examined and the behaviour of the concrete was observed. Consequently, it was verified that this new spalling resistance technique is feasible in practice. 相似文献