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141.
142.
Soichi Arai Hideki Suzuki Masao Fujimaki Yosito Sakurai 《Bioscience, biotechnology, and biochemistry》2013,77(4):364-369
Ethanol (1:1) extract of defatted soybean flour was fractionated systematically and the resulting phonolic acid fraction was investigated. This fraction had strong phenol-like flavor and contained at least seven phenolic acids including syringic, vanillic, ferulic, gentisic, salicylic, p-coumaric, and p-hydroxybenzoic acids. The main component among these was syringic acid, which was isolated as 3,5-dinitrobenzoate.In addition, two isomers of chlorogenic acids, presumably isochlorogenic and chlorogenic acids approximately in a ratio of 1 : 10, were found in this extract. These substances have sour, bitter and astringent flavors. 相似文献
143.
Hideyuki Furukawa Hideki Matsuo Takashi Deguchi Akio Shiga Hirotoshi Samejima 《Bioscience, biotechnology, and biochemistry》2013,77(5):617-623
l-Lysine monohydrochloride and d-glucose were allowed to react in a bicarbonate buffer of pH 8.8 under refluxing. The reaction mixture was then chromatographed on a thin-layer plate of Kiesel Gel using n-propanol ethyl-acetate water 25% aqueous ammonia (6: 1: 2: 1 v/v) as a developing agent. Elson-Morgan-reactive spots on the chromatogram were eluted individually, and each of the eluates was incubated with L. bifidus var. pennsylvanicus in a defined medium. A certain fraction on the chromatogram showed remarkably promoting effect on both the acid productivity and the growth of the organism. And such effect of the fraction was much stronger than that of N-acetyl-d-glucosamine which had been known as a “Bifidus Factor” 相似文献
144.
Nobumaro Kawashima Harui Fukushima Ayako Imai Einosuke Tamaki 《Bioscience, biotechnology, and biochemistry》2013,77(9):1141-1145
A leaf protease of tobacco whose activity was enhanced during curing was purified about 60 times with ammonium sulfate fractionation, ethanol precipitation, calcium phosphate gel treatment and Sephadex G-200 column chromatography, and some properties of the protease were examined. The purified enzyme showed the optimum pH at 5.5 and the optimum temperature at 60°C. The protease activity was stable between pH 4.5 and 5.5 at 50°G or at pH 5.5 below 40°C for 1 hr, but completely destroyed at 70°C during 1 hr. The protease activity was greatly activated by reducing agents such as cysteine, glutathione or mercaptoethanol and inhibited by p-chloromercuribenzoate, phenyl- mercuric acetate or silver ions. Metal ions except for silver ion and ethylenediamine tetraacetic acid did not affect the protease activity so far examined. 相似文献
145.
Youji Nakagawa Toru Hasebe Miyuki Ishiai Hideki Yamamura Yuzuru Iimura Masayuki Hayakawa 《Bioscience, biotechnology, and biochemistry》2013,77(4):714-717
We constructed a plasmid that expresses FLO11 encoding a cell surface glycoprotein of Saccharomyces cerevisiae under the control of a constitutive promoter. This plasmid conferred pellicle-forming ability on the non-pellicle-forming industrial strain of S. cerevisiae at the air–liquid interface of the glucose-containing liquid medium. The induced pellicle-forming cells exhibited tolerance to furfural, which is a key toxin in lignocellulosic hydrolysates, in ethanol production. 相似文献
146.
Hiroshi Itoh Keisuke Kawashima Ichiro Chibata 《Bioscience, biotechnology, and biochemistry》2013,77(10):2227-2233
The rapid microbiological method for determination of amino acids was established. It is composed of 3 steps of culture; inoculum culture, intermediate culture, and assay culture. The inoculum culture is the same as that of ordinary method using Leuc. mesenteroides P–60. For the intermediate culture, which is carried out between the inoculum and assay cultures, the basal medium supplemented with appropriate amount of the amino acid to be determined is employed. The large amount of cells at logarithm phase grown in the intermediate culture are dispersed and used as inoculum for the assay culture. By this technique the assay can be performed by 2.5 to 3.5 hr of assay culture after 2 to 3 hr-intermediate culture.The technique can be applied to the determination of amino acids in the mixture and the results agree with those obtained by ordinary method. 相似文献
147.
Yoshimasa Taniguchi Yasuko Matsukura Harumi Taniguchi Hideki Koizumi Mikio Katayama 《Bioscience, biotechnology, and biochemistry》2013,77(10):1684-1694
The bitter acids in hops (Humulus lupulus L.) and beer, such as α-, β-, and iso-α-acids, are known to affect beer quality and display various physiological effects. However, these compounds readily oxidize, and the effect of the oxides on the properties of beer or their potential health benefits are not well understood. In this study, we developed a simple preparative method for the bitter acid oxide fraction derived from hops and designated the constituents as matured hop bitter acids (MHBA). HPLC-PDA-ESI/HRMS and MS2 revealed that MHBA are primarily composed of α-acid-derived oxides, which possess a common β-tricarbonyl moiety in their structures similar to α-, β-, and iso-α-acids. We also developed a quantitative analytical method of whole MHBA by HPLC, which showed high precision and reproducibility. Using our newly developed method, the concentration of whole MHBA in several commercial beers was evaluated. Our results will promote the study of bitter acid oxides. 相似文献
148.
Xiang Li Emily A. Foley Shigehiro A. Kawashima Kelly R. Molloy Yinyin Li Brian T. Chait Tarun M. Kapoor 《Protein science : a publication of the Protein Society》2013,22(3):287-295
Post‐translational modifications (PTM) of proteins can control complex and dynamic cellular processes via regulating interactions between key proteins. To understand these regulatory mechanisms, it is critical that we can profile the PTM‐dependent protein–protein interactions. However, identifying these interactions can be very difficult using available approaches, as PTMs can be dynamic and often mediate relatively weak protein–protein interactions. We have recently developed CLASPI (cross‐linking‐assisted and stable isotope labeling in cell culture‐based protein identification), a chemical proteomics approach to examine protein–protein interactions mediated by methylation in human cell lysates. Here, we report three extensions of the CLASPI approach. First, we show that CLASPI can be used to analyze methylation‐dependent protein–protein interactions in lysates of fission yeast, a genetically tractable model organism. For these studies, we examined trimethylated histone H3 lysine‐9 (H3K9Me3)‐dependent protein–protein interactions. Second, we demonstrate that CLASPI can be used to examine phosphorylation‐dependent protein–protein interactions. In particular, we profile proteins recognizing phosphorylated histone H3 threonine‐3 (H3T3‐Phos), a mitotic histone “mark” appearing exclusively during cell division. Our approach identified survivin, the only known H3T3‐Phos‐binding protein, as well as other proteins, such as MCAK and KIF2A, that are likely to be involved in weak but selective interactions with this histone phosphorylation “mark”. Finally, we demonstrate that the CLASPI approach can be used to study the interplay between histone H3T3‐Phos and trimethylation on the adjacent residue lysine 4 (H3K4Me3). Together, our findings indicate the CLASPI approach can be broadly applied to profile protein–protein interactions mediated by PTMs. 相似文献
149.
Rui Nouchi Yasuyuki Taki Hikaru Takeuchi Hiroshi Hashizume Takayuki Nozawa Toshimune Kambara Atsushi Sekiguchi Carlos Makoto Miyauchi Yuka Kotozaki Haruka Nouchi Ryuta Kawashima 《PloS one》2013,8(2)
Background
Do brain training games work? The beneficial effects of brain training games are expected to transfer to other cognitive functions. Yet in all honesty, beneficial transfer effects of the commercial brain training games in young adults have little scientific basis. Here we investigated the impact of the brain training game (Brain Age) on a wide range of cognitive functions in young adults.Methods
We conducted a double-blind (de facto masking) randomized controlled trial using a popular brain training game (Brain Age) and a popular puzzle game (Tetris). Thirty-two volunteers were recruited through an advertisement in the local newspaper and randomly assigned to either of two game groups (Brain Age, Tetris). Participants in both the Brain Age and the Tetris groups played their game for about 15 minutes per day, at least 5 days per week, for 4 weeks. Measures of the cognitive functions were conducted before and after training. Measures of the cognitive functions fell into eight categories (fluid intelligence, executive function, working memory, short-term memory, attention, processing speed, visual ability, and reading ability).Results and Discussion
Our results showed that commercial brain training game improves executive functions, working memory, and processing speed in young adults. Moreover, the popular puzzle game can engender improvement attention and visuo-spatial ability compared to playing the brain training game. The present study showed the scientific evidence which the brain training game had the beneficial effects on cognitive functions (executive functions, working memory and processing speed) in the healthy young adults.Conclusions
Our results do not indicate that everyone should play brain training games. However, the commercial brain training game might be a simple and convenient means to improve some cognitive functions. We believe that our findings are highly relevant to applications in educational and clinical fields.Trial Registration
UMIN Clinical Trial Registry 000005618. 相似文献150.
Yoritaka Akimoto Akitake Kanno Toshimune Kambara Takayuki Nozawa Motoaki Sugiura Eiichi Okumura Ryuta Kawashima 《PloS one》2013,8(3)
Although many studies have investigated the neural basis of top-down and bottom-up attention, it still requires refinement in both temporal and spatial terms. We used magnetoencephalography to investigate the spatiotemporal dynamics of high-gamma (52–100 Hz) activities during top-down and bottom-up visual attentional processes, aiming to extend the findings from functional magnetic resonance imaging and event-related potential studies. Fourteen participants performed a 3-stimulus visual oddball task, in which both infrequent non-target and target stimuli were presented. We identified high-gamma event-related synchronization in the left middle frontal gyrus, the left intraparietal sulcus, the left thalamus, and the visual areas in different time windows for the target and non-target conditions. We also found elevated imaginary coherence between the left intraparietal sulcus and the right middle frontal gyrus in the high-gamma band from 300 to 400 ms in the target condition, and between the left thalamus and the left middle frontal gyrus in theta band from 150 to 450 ms. In addition, the strength of high-gamma imaginary coherence between the left middle frontal gyrus and left intraparietal sulcus, between the left middle frontal gyrus and the right middle frontal gyrus, and the high-gamma power in the left thalamus predicted inter-subject variation in target detection response time. This source-level electrophysiological evidence enriches our understanding of bi-directional attention processes: stimulus-driven bottom-up attention orientation to a salient, but irrelevant stimulus; and top-down allocation of attentional resources to stimulus evaluation. 相似文献