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61.
Lee J Park E Park T Lee J Sung M Yi W 《Journal of nanoscience and nanotechnology》2011,11(8):7299-7302
Upper-directionally grown nanorods were synthesized on a large scale by a simple method of direct heating of Cu foil in air. Hybrid CuO/ZnO nanorods were fabricated by ZnO thin film coating using magnetron sputtering. Field emission (FE) measurements of CuO and hybrid CuO/ZnO nanorod films show that they have turn-on field of 3.81 and 3.24 V/microm and a current density of 0.39 and 1.1 microA/cm2 under an applied field of about 6.6 V/microm, respectively. By comparing X-ray photoelectron spectroscopy analysis and the FE properties of two types of samples, we concluded that the narrowing of band gap due to the change of electron binding energy of hybrid CuO/ZnO nanorods effectively improved FE. 相似文献
62.
Bacterial alkaline phosphatase (BAP) was site-specifically and covalently immobilized on magnetic particles (MPs) using the enzymatic reaction of microbial transglutaminase (MTG). Immobilization efficiency was affected by the chemical surface treatment of MPs and immobilized BAP exhibited more than 90% of the initial activity after 10 rounds of recycling. 相似文献
63.
Misun Sung Sung Sun Park Sung-Soo Kim Chan-Kyu Han Jung-Mu Hur 《Food science and biotechnology》2014,23(5):1615-1621
The antioxidant activities and hepatoprotective effects of Schizandra chinensis Baill. extracts (SCE) were evaluated. The contents of the active components schisandrin, schisandrin C, gomisin A, and gomisin N in SCE were 8.802±1.390, 1.011±0.203, 0.954±0.191, and 3.351±0.829 mg/g, respectively. The antioxidant activity of SCE was measured based on the DPPH free radical scavenging activity and the superoxide dismutase (SOD)-like activity. The IC50 values for the DPPH radical scavenging activity and SOD-like activity were 18.1 and 44.2mg/mL, respectively. The protective effect of SCE against alcohol-induced oxidative injury in HepG2 cells was investigated. Cells pretreated with SCE (100–400 μg/mL) showed an increased resistance to oxidative stress in a dose-dependent manner. Expressions of Bcl-2 and pro-caspase-3 proteins were induced by SCE in HepG2 cells. SCE can be useful for management of antioxidant and hepatoprotective effects. 相似文献
64.
Onions with or without heating (100 °C, 30 min) were extracted with water or methanol, and antioxidant and antimicrobial activities of onion extracts were evaluated. Product characteristics of fresh pork patties containing various onion extracts were measured during refrigerated storage. Water extracts of onions showed higher extraction yield and iron chelating ability than methanol extracts (P < 0.05), whereas, the latter was more effective than the former in phenolic compounds and reducing power (P < 0.05). The addition of onion extracts [water extract from fresh onion (WEFO), methanol extract from heated onion (MEHO) and their combinations (WEFMEHO)] to pork patties decreased redness, increased yellowness, and inhibited lipid peroxidation (P < 0.05). One per cent of WEFMEHO in pork patties had antioxidant activities as effective as butylated hydroxyl toluene (BHT, 0.01%). Redness and yellowness decreased and increased with the addition of onion extract, respectively (P < 0.05). 相似文献
65.
Striated muscle fibers (or cells) were observed in three of the six swine pineal glands. The muscle fibers occurred in clusters of several fibers about the parenchymal blood vessels. They were in general poorly developed, lacked regular cross striations and were not readily recognized histologically. The muscle fibers were, however, easily identified on electron microscopy because of the myofilaments they contain. In most of the muscle fibers, the myofilaments were arranged in ill-defined, disorderly bundles and rarely formed well-defined myofibrils and sarcomeres. The sarcotubular system was also poorly developed and triads were sparse and randomly scattered. Leptomeres were observed in several muscle fibers. The source of the muscle fibers in the pineal glands is not well understood and, whatever the source may be, the muscle fibers seem to remain poorly developed in the pineal glands. 相似文献
66.
Sung Jeehye Yang Jinwoo Kim Younghwa Kim Myunghee Jeong Heon Sang Lee Junsoo 《Food science and biotechnology》2016,25(5):1457-1461
Food Science and Biotechnology - This study investigated the effect of defatted pepper seed ethanolic extract (DPSE) on high-fat diet-induced obesity in C57BL/6J mice. The mice were fed a normal... 相似文献
67.
Young Heui Kim Ki Soo Kim Chang Sung Han Hong Chul Yang Sun Hee Park Kang II Ko Soo Hee Lee KI HO Kim Nam Ho Lee Jung MI Kim Kyunghun Son 《International journal of cosmetic science》2007,29(6):487-488
In order to search for new active cosmetic ingredients of natural origin, we screened about 60 plants collected from Jeju Island, which is located in the southernmost part of the Republic of Korea. We investigated their free radical scavenging activity, elastase inhibition activity, and reduction of MMP-1 mRNA expression for the development of anti-aging ingredients as raw materials for use in cosmetics. In the free radical scavenging capacity assay, 12 extracts, including Typha orientalis (seed) and Torreya nucifera (leaf), showed significant free radical scavenging activity (up to SC50 < 30 μg/ml). Among these extracts, Nymphaea tetragona (rhizome) extract showed the highest free radical scavenging activity (SC50 = 4.7 μg/ml). In the anti-elastase inhibition assay, seven extracts, including T. orientalis (seed) and Persicaria hydropiper (whole plant), showed high inhibitory activity (>50% at 100 μg/ml). Among these extracts, P. hydropiper (whole plant) extract showed the highest elastase inhibition activity (IC50 = 46.7 μg/ml). In the MMP-1 expression assay using RT-PCR, T. orientalis (seed), Pyrrosia hastata (root), and Capsicum annum (whole plant) showed slightly lower inhibition activity than EGCG, which was used as a control. Furthermore, four extracts, including P. hydropiper (whole plant), Filipendula glaberrima (root), N. tetragona (root), and Camellia japonica (leaf), completely inhibited the expression of MMP-1 in human fibroblast cells. The results showed that four of the 60 plant extracts may hold potential for use as natural active ingredients for anti-aging cosmetics. 相似文献
68.
Sung Keun Jung Tae-Gyu Lim Sang Gwon Seo Hyong Joo Lee Young-Sun Hwang Myoung-Gun Choung Ki Won Lee 《Food science and biotechnology》2013,22(2):507-513
Cyanidin-3-O-(2″-xylosyl)-glucoside (C-3-O-(2″-xylosyl)-G) was analyzed as an active constituent from the fruit of Siberian ginseng (Acanthopanax senticosus) using a HPLC diode array detection-electrospray ionization/mass spectrometry analysis system and the effect of C-3-O-(2″-xylosyl)-G on UVB-induced inflammatory signaling in JB6 P+ cells was investigated. C-3-O-(2″-xylosyl)-G inhibited UVB-induced cyclooxygenase (COX)-2 expression and promoter binding activity in JB6 P+ cells and JB6 P+ cells stably transfected with the COX-2 luciferase reporter plasmid. It inhibited both the UVB-induced activator protein-1 (AP-1) and nuclear factor (NF)-κB transactivation in JB6 P+ cells stably transfected with the AP-1 and NF-κB luciferase reporter plasmids. Additionally, C-3-O-(2″-xylosyl)-G significantly suppressed UVB-induced upregulated phosphorylation of c-Jun N terminal kinase, MEK/extracellular signaling kinase, and mitogen activated protein kinase kinase (MAPKK) 3/6 in JB6 P+ cells. These results indicate that C-3-O-(2″-xylosyl)-G may be a promising chemopreventive material that acts by suppressing COX-2 expression and AP-1 and NF-κB transactivation and JNK, MAPKK3/6, and MEK/ERK1/2 phosphorylation. 相似文献
69.
Mi Ra Lee Jing Gang Hou Shahnaz Begum Jian Jie Xue Yun Bo Wang Chang Keun Sung 《Food science and biotechnology》2013,22(6):1747-1751
This study evaluates three edible mushrooms: Lentinus edodes, Sparassis crispa, and Mycoleptodonoides aitchisonii, in terms of acetylcholinesterase (AChE) inhibition, antioxidant potency and constituents free amino acids and mineral. The concentration of essential amino acids was found to be 34.10 mg/g in M. aitchisonii, 26.25 mg/g in S. crispa, 25.99 mg/g in L. edodes. S. crispa displayed the highest DPPH scavenging activity and phenolic contents. The best results for AChE inhibition were obtained from M. aitchisonii. These results suggest that M. aitchisonii has high potential for cognitive improvement by AChE inhibition and antioxidant potency. 相似文献
70.
Yon-Suk Kim Jin-Woo Hwang Si-Heung Sung Sun-Joo Park Yong-Tae Kim Eun-Kyung Kim Sang-Ho Moon Byong-Tae Jeon Pyo-Jam Park 《Food science and biotechnology》2015,24(2):735-741
Carvacrol is a monoterpenic phenol present in Thymus quinquecostatus Celak. The protective effects of carvacrol against tert-butyl hydroperoxide (t-BHP)-induced oxidative damage were investigated in human Chang cells. Cells treated with carvacrol extracts promoted Chang cell survival and protection was associated with stabilization of the mitochondrial membrane potential (MMP), prevention of oxidative stress-triggered reactive oxygen species (ROS), and lipid peroxidation (MDA production). In addition, Annexin V/PI, observed using Hoechst staining, indicated that carvacrol inhibited t-BHP-induced cell damage and stimulated the antioxidant capability of Chang cells due to elevation of glutathione (GSH) levels, which were reduced by t-BHP treatment. Carvacrol prevented oxidative stress-induced Chang cell damage via suppression of ROS and MDA levels, and increased GSH levels. 相似文献