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841.
Production and antioxidant activity of alcoholic beverages made from various cereal grains using Monascus purpureus NBRC 5965 下载免费PDF全文
Ryoichi Takeshita Noriaki Saigusa Yuji Teramoto 《Journal of the Institute of Brewing》2016,122(2):350-354
Monascus sp., which produces red pigments, has been utilized for brewing red alcoholic beverages and fermented foods in China and Okinawa, Japan. Novel red alcoholic beverages with antioxidant activity were made from cereal grains of various colours utilizing the saccharifying activity of Monascus purpureus NBRC 5965. The alcoholic beverage made from black rice and beni koji prepared with M. purpureus NBRC 5965 showed a deep red colour, and the DPPH radical scavenging activity of the alcoholic beverage made from black rice and beni koji was around a 3300 µm Trolox equivalent/mL‐beverage. The antioxidant activity of this alcoholic beverage is thought to be a result of the combination of Monascus pigments and black rice anthocyanin. The DPPH radical scavenging activity and inhibitory activity of lipid peroxidation of an alcoholic beverage made with beni koji were higher than those of an alcoholic beverage made with ki koji prepared with Aspergillus oryzae. Copyright © 2016 The Institute of Brewing & Distilling 相似文献
842.
Polyisoprene in o-dichlorobenzene solution were reacted with maleic anhydride at 180°C under nitrogen atmosphere to form modified polyisoprene with α-substituted succinic anhydride groups. These groups were converted by reaction with hydroxyethyl cinnamate in pyridine at 25°C to cinnamate groups. Various amounts of cinnamate groups as photosensitive groups could be easily introduced into polyisoprene up to 75 mol % toward polyisoprene repeating units. Polymer glass transition temperatures of the products rose linearly from ?70°C for polyisoprene to 60°C with increasing amounts of the side groups. The solution viscosity of the products in chloroform decreased from 9.34 for polyisoprene to 0.77 with increasing amounts of the side groups. The photosensitivity of the polyisoprene, which is based on the photodimerization of the cinnamate groups, was higher than that of polypentenamer having cinnamate groups due to the interaction by the free carboxylic acids neighboring with the cinnamate groups. The photosensitivity of the cinnamate group was kinetically evaluated in terms of the dependence on the polymer glass transition temperature. The interaction by the free carboxylic acid groups in the polyisoprene reduced the dependence of the photosensitivity on the mobility of the polymer segments. Linear relationship between observed rate constants of the photodimerization and (TUV ? Tg + 50)?1 was obtained and the slope of the line changed and became very small at higher glass transition temperatures. 相似文献
843.
Takayuki Otsu Masahiro Yoshioka Akikazu Matsumoto Kohei Shiraishi 《Polymer Bulletin》1991,26(2):159-164
Summary High molecular weight poly(dialkyl fumarate)s bearing n-alkyl esters such as an octadecyl group were prepared efficiently from poly(di-tert-butyl fumarate) by the one-pot synthesis, i.e. both elimination of isobutene from the tert-butyl ester and the subsequent esterification were performed in a corresponding alcohol at 170–180°C in a one-pot without isolating poly(fumaric acid). The resulting polymers were characterized by IR and NMR spectroscopies and GPC. The polymers with various contents of an octadecyl group in the side chain were also obtained similarly from the copolymer of di-tert-butyl fumarate with diisopropyl fumarate. 相似文献
844.
Conditions for direct analyses of various aromatic compounds in water by steam carrier gas chromatography (SCGC) were studied by using a hydrogen flame ionization detector and acid washed Chromosorb P modified with 3.5 ± 0.3 wt% of phosphoric acid as a stationary solid in 2 mm i.d. × 2 m glass column. A flowrate of approx. 60 ml min−1 of carrier steam and a column temperature of 150–180°C were considered to be the optimum conditions for analyses of water samples containing several groups of aromatic compounds. Under constant conditions, aromatic compounds were generally eluted in order of their boiling points. The relationship between the retention time and the boiling point was obtained for two groups of substitutes of benzene and naphthalene. The retention time of a substitute of benzene or naphthalene can, therefore, be predicted from its boiling point, and conversely, the aromatic compounds in an unknown water sample can be characterized for identification from their retention times. By SCGC, various aromatic compounds in water at concentrations higher than approx. 30 μg l−1 can be analysed directly without complicated pre-treatment. 相似文献
845.
We report an anomalous light transmission phenomenon for a nanoaperture on an opaque screen when the aperture is covered with an opaque cap. In conventional optics, light transmission must decrease when the aperture is capped. However, we found that light transmission is enhanced when the nanodisk is in close proximity to the aperture at a wavelength close to the plasmon resonance. This effect even occurs when the disk is larger than the aperture. 相似文献
846.
Satoshi Watanabe Hiroshi Hyodo Hirohisa Taguchi Kohei Soga Yoshifumi Takanashi Mutsuyoshi Matsumoto 《Advanced functional materials》2011,21(22):4264-4269
It is demonstrated that patterned inorganic phosphor films consisting of rare earth ion doped nanoparticles (RE‐NPs) can be fabricated on plastic sheets using calcination‐ and etching‐free photolithography. Green up‐conversion luminescence and near‐infrared (NIR) fluorescence appears from the RE‐NPs that are prepared from Y2O3 doped with 1 mol% Er3+ and 0.85 mol% Yb3+. The diameter of the RE‐NPs is estimated to be about 300 nm using dynamic light scattering. Visible transmittance of the RE‐NP film fabricated by dip‐coating is more than 90%. Patterned RE‐NP films are obtained by dip‐coating the RE‐NPs on patterned photoresist films fabricated by UV exposure through a photomask, followed by selective removal of the photoresist. Optical, fluorescence, scanning electron, atomic force, and Kelvin probe force microscopies are used for the characterization of the patterned RE‐NP films. The present methodology enables fabrication of patterned RE‐NP films, not only on inorganic substrates but also on plastic sheets, with low cost and material consumption. 相似文献
847.
Toru Kuramoto Denan Jin Koji Komeda Kohei Taniguchi Fumitoshi Hirokawa Shinji Takai Kazuhisa Uchiyama 《International journal of molecular sciences》2021,22(22)
Acute pancreatitis is still a life-threatening disease without an evidenced therapeutic agent. In this study, the effect of chymase in acute pancreatitis and the possible effect of a chymase inhibitor in acute pancreatitis were investigated. Hamsters were subcutaneously administered 3.0 g/kg of L-arginine to induce acute pancreatitis. Biological markers were measured 1, 2, and 8 h after L-arginine administration. To investigate the effect of a chymase inhibitor, a placebo (saline) or a chymase inhibitor TY-51469 (30 mg/kg) was given 1 h after L-arginine administration. The survival rates were evaluated for 24 h after L-arginine administration. Significant increases in serum lipase levels and pancreatic neutrophil numbers were observed at 1 and 2 h after L-arginine administration, respectively. Significant increases in pancreatic neutrophil numbers were observed in the placebo-treated group, but they were significantly reduced in the TY-51469-treated group. A significant increase in the pancreatic tumor necrosis factor-α mRNA level was observed in the placebo-treated group, but it disappeared in the TY-51469-treated group. Chymase activity significantly increased in the placebo-treated group, but it was significantly reduced by treatment with TY-51469. The survival rate significantly improved in the TY-51469-treated group. A chymase inhibitor may become a novel therapeutic agent for acute pancreatitis. 相似文献
848.
Yueyuan Zhou Yusuke Yamamoto Fumitaka Takeshita Tomofumi Yamamoto Zhongdang Xiao Takahiro Ochiya 《International journal of molecular sciences》2021,22(2)
Programmed cell death ligand-1 (PD-L1) overexpressed on cancer cells has emerged as a key inhibitor that maintains the immunosuppressive microenvironment through its interaction with the PD-1 receptor in cancer. Here, we demonstrated that miR-424-5p delivery via extracellular vesicles (EVs) derived from adipose tissue-mesenchymal stromal cells (AT-MSCs) partly promotes proinflammation and enhances antitumor cytotoxicity in vitro and in vivo. Triple negative breast cancer (TNBC) exhibits increased expression of PD-L1, and PD-L1 is positively correlated with the overall survival of patients with TNBC. PD-L1 shows relatively higher expression in MDA-MB-231 (MM231) cells and can be downregulated by miR-424-5p. Furthermore, miR-424-5p transported by EVs can increase the secretion of proinflammatory cytokines, decrease the secretion of anti-inflammatory cytokines and promote the apoptosis of tumor cells. The intratumoral administration of miR-424-5p-EVs significantly slowed tumor growth. In conclusion, these results demonstrate that EVs may serve as a delivery system for novel immunotherapies for TNBC through the miR-424-5p/PD-L1 pathway. 相似文献
849.
Jiro Shimaya Yuichiro Yoshikawa Kohei Ogawa Hiroshi Ishiguro 《Journal of Computer Assisted Learning》2021,37(3):621-631
Encouraging students to actively ask questions during lectures is a formidable challenge that can be addressed through innovative use of information technology. We developed a robotic system that allows students in a lecture to collaboratively decide questions to be asked by a humanoid robot. To verify whether the system reduces hesitation to ask questions during lectures, 62 university students were divided into two groups, and each attended two different mock lectures on the Nobel Prize in Physics. Two lectures were conducted with and without the proposed system in counterbalanced order. Results suggested that students who were usually hesitant to ask questions during lectures became less hesitant to ask questions face-to-face when they could use the proposed system. Moreover, the perceived activeness in the lectures increased when using the system. Multiple regression analyses revealed that certain student actions, particularly tweeting and showing agreement with the questions posted by others, were correlated with an increase in perceived activeness. 相似文献
850.
Morimoto K Takeshita T Inoue-Sakurai C Maruyama S 《The Science of the total environment》2001,270(1-3):3-11
We investigated the association of lifestyle and mental health status with natural killer (NK) cell and lymphokine-activated killer (LAK) cell activities in healthy males. NK cell activity was determined in 105 male workers and LAK cell activity was determined in 54 male workers. Peripheral blood was obtained from each subject and peripheral blood mononuclear cells (PBMC) were isolated from the blood. These PBMC were used as effector cells. LAK cells were generated by incubation of PBMC with interleukin-2 for 72 h. NK cell activity against NK-sensitive K562 cells and LAK cell activity against NK-resistant Raji cells were examined by 51Cr release assay. Overall lifestyles were evaluated according to the answers on a questionnaire regarding eight health practices (cigarette smoking, alcohol consumption, eating breakfast, hours of sleep, hours of work, physical exercise, nutritional balance, mental stress). Subjects with a good overall lifestyle showed significantly higher NK cell (P < 0.05) and LAK cell (P < 0.05) activities than those with a poor overall lifestyles. Among eight lifestyle factors, cigarette smoking has relatively strong effects on NK cell and LAK cell activities. Subjects who complained of unstable mental status had significantly lower NK cell activity than those who reported stable mental status. When subjects were divided into four groups by lifestyle and mental health status, subjects who had poor or moderate lifestyle and reported unstable mental status showed the lowest NK cell activity and subjects who had good lifestyle and reported stable mental status showed the highest NK cell activity among four groups. 相似文献