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131.
Takehiko Yamamoto Junichi Kumada Teruo Sawai 《Bioscience, biotechnology, and biochemistry》2013,77(3):185-191
The purification of yeast invertase was attempted by application of the chromatographic method using Duolite C-10, a sulfonic acid cation exchange resin. This method was found to be extremely simple in process and significantly effective for the improvement of purity of the enzyme, compared with those other methods reported, hitherto. In the present paper, the procedure of the purification and some properties of the enzyme obtained thereby, are described, and some discussion of the implications is presented. 相似文献
132.
Minora Nakajima Junichi Oda Hiroshi Fukami 《Bioscience, biotechnology, and biochemistry》2013,77(10):695-699
Nodakenetin and marmesin were synthesized from β-resorcylaldehyde through 2-(α-hy-droxyisopropyl)-6-hydroxycoumaran. 相似文献
133.
Toshiro Samejima Yoshihiko Soh Toshimasa Yano 《Bioscience, biotechnology, and biochemistry》2013,77(12):2285-2290
The equilibrium moisture contents of sun-cured (Kroumougrad), flue-cured (Bright Yellow—4) and air-cured (Burley-21 and Matsukawa) tobaccos were measured over a relative humidity range from 5 to 80% at 20°C. The moisture sorption isotherms of tobaccos were of sigmoid type, and classified into two groups. In a lower humidity range below ca. 40% RH, the A group (Kroumougrad and BY-4) had a smaller moisture sorption capacity than B group (Burley-21 and Matsukawa), while in a higher humidity range above ca. 50% RH the former had a larger moisture sorption capacity than the latter. By extracting with water, the moisture content of BY-4 was increased in the lower humidity range, while it decreased in the higher humidity range. However, the moisture content of Matsukawa was scarecely changed by extracting it with water. These results suggest that the differences in equilibrium moisture content with the type of curing were due to the differences in contents of water soluble com- ponents. To control the hygroscopic properties of a tobacco, therefore, the influences of the addition of sucrose and glycerol on the equilibrium moisture content were quantitatively analysed. The moisture sorption capacity of tobacco was greatly different from its nitrogen sorption capacity. The specific surface area of tobacco calculated from moisture sorption isotherm was ca. 110 times larger than the specific surface area calculated from the nitrogen sorption isotherm. Both the nitrogen and moisture sorption data should be necessary for better understanding of the complicated sorption-desorption phenomena in tobaccos. 相似文献
134.
Phyu Phyu Khine Zar Satoshi Yano Kozue Sakao Fumio Hashimoto Takayuki Nakano Makoto Fujii 《Bioscience, biotechnology, and biochemistry》2013,77(10):1731-1737
Fresh loquat leaves have been used as folk health herb in Asian countries for long time, although the evidence supporting their functions is still minimal. This study aimed to clarify the chemopreventive effect of loquat tea extract (LTE) by investigating the inhibition on proliferation, and underlying mechanisms in human promyelocytic leukemia cells (HL-60). LTE inhibited proliferation of HL-60 in a dose-dependent manner. Molecular data showed that the isolated fraction of LTE induced apoptosis of HL-60 as characterized by DNA fragmentation; activation of caspase-3, -8, and -9; and inactivation of poly(ADP)ribose polymerase. Moreover, LTE fraction increased the ratio of pro-apoptotic Bcl-2-associated X protein (Bax)/anti-apoptotic myeloid cell leukemia 1 (Mcl-1) that caused mitochondrial membrane potential loss and cytochrome c released to cytosol. Thus, our data indicate that LTE might induce apoptosis in HL-60 cells through a mitochondrial dysfunction pathway. These findings enhance our understanding for chemopreventive function of loquat tea. 相似文献
135.
Junichi Ueda Takao Yokota Nobutaka Takahashi Michio Yoshida Jiro Kato 《Bioscience, biotechnology, and biochemistry》2013,77(12):3083-3086
A root growth-promoting factor was isolated from Artemisia capillaris Thunb. The chemical structure of this compound was elucidated as methyl 3-(3-methylbut-2-enoyl)-4-hydroxycinnamate (capillarol) on the basis of its spectroscopic analysis. At 5×10–4m this compound promoted rice root growth to 180% of the control value. 相似文献
136.
Keiji Yano Naoki Higashi Satoshi Nakamura Kei Arima 《Bioscience, biotechnology, and biochemistry》2013,77(9):1363-1365
The transglucosidation reaction of brewer’s yeast α-glucosidase was examined under the co-existence of l-sorbose and phenyl-α-glucoside. As the transglucosidation products, three kinds of new disaccharide were chromatographically isolated. It was presumed that these disaccharides consisting of d-glucose and l-sorbose were 1-O-α-d-glucopyranosyl-l-sorbose ([α]D+89.0), 3-O-α-d-glucopyranosyl-l-sorbose ([α]D+69.1) and 4-O-α-d-glucopyranosyl-l-sorbose ([α]D+81.0). The principal product formed in the enzyme reaction was 1-O-α-d-glucopyranosyl-l-sorbose. 相似文献
137.
Molecular dynamics (MD) simulations using all-atom and explicit solvent models provide valuable information on the detailed behavior of protein–partner substrate binding at the atomic level. As the power of computational resources increase, MD simulations are being used more widely and easily. However, it is still difficult to investigate the thermodynamic properties of protein–partner substrate binding and protein folding with conventional MD simulations. Enhanced sampling methods have been developed to sample conformations that reflect equilibrium conditions in a more efficient manner than conventional MD simulations, thereby allowing the construction of accurate free-energy landscapes. In this review, we discuss these enhanced sampling methods using a series of case-by-case examples. In particular, we review enhanced sampling methods conforming to trivial trajectory parallelization, virtual-system coupled multicanonical MD, and adaptive lambda square dynamics. These methods have been recently developed based on the existing method of multicanonical MD simulation. Their applications are reviewed with an emphasis on describing their practical implementation. In our concluding remarks we explore extensions of the enhanced sampling methods that may allow for even more efficient sampling. 相似文献
138.
Izumi Uno Takashi Kozaka Daisuke Miwa Yoji Kitamura Mohammad Anwar-ul Azim Kazuma Ogawa Junichi Taki Seigo Kinuya Kazuhiro Shiba 《PloS one》2016,11(1)
Purpose
To develop a superior VAChT imaging probe for SPECT, radiolabeled (-)-OIDV and (+)-OIDV were isolated and investigated for differences in their binding affinity and selectivity to VAChT, as well as their in vivo activities.Procedures
Radioiodinated o-iodo-trans-decalinvesamicol ([125I]OIDV) has a high binding affinity for vesicular acetylcholine transporter (VAChT) both in vitro and in vivo. Racemic [125I]OIDV was separated into its two optical isomers (-)-[125I]OIDV and (+)-[125I]OIDV by HPLC. To investigate VAChT binding affinity (Ki) of two OIDV isomers, in vitro binding assays were performed. In vivo biodistribution study of each [125I]OIDV isomer in blood, brain regions and major organs of rats was performed at 2,30 and 60 min post-injection. In vivo blocking study were performed to reveal the binding selectivity of two [125I]OIDV isomers to VAChT in vivo. Ex vivo autoradiography were performed to reveal the regional brain distribution of two [125I]OIDV isomers and (-)-[123I]OIDV for SPECT at 60 min postinjection.Results
VAChT binding affinity (Ki) of (-)-[125I]OIDV and (+)-[125I]OIDV was 22.1 nM and 79.0 nM, respectively. At 2 min post-injection, accumulation of (-)-[125I]OIDV was the same as that of (+)-[125I]OIDV. However, (+)-[125I]OIDV clearance from the brain was faster than (-)-[125I]OIDV. At 30 min post-injection, accumulation of (-)-[125I]OIDV (0.62 ± 0.10%ID/g) was higher than (+)-[125I]OIDV (0.46 ± 0.07%ID/g) in the cortex. Inhibition of OIDV binding showed that (-)-[125I]OIDV was selectively accumulated in regions known to express VAChT in the rat brain, and ex vivo autoradiography further confirmed these results showing similar accumulation of (-)-[125I]OIDV in these regions. Furthermore, (-)-[123I]OIDV for SPECT showed the same regional brain distribution as (-)-[125I]OIDV.Conclusion
These results suggest that radioiodinated (-)-OIDV may be a potentially useful tool for studying presynaptic cholinergic neurons in the brain. 相似文献139.
140.
Michael Abberton Jacqueline Batley Alison Bentley John Bryant Hongwei Cai James Cockram Antonio Costa de Oliveira Leland J. Cseke Hannes Dempewolf Ciro De Pace David Edwards Paul Gepts Andy Greenland Anthony E. Hall Robert Henry Kiyosumi Hori Glenn Thomas Howe Stephen Hughes Mike Humphreys David Lightfoot Athole Marshall Sean Mayes Henry T. Nguyen Francis C. Ogbonnaya Rodomiro Ortiz Andrew H. Paterson Roberto Tuberosa Babu Valliyodan Rajeev K. Varshney Masahiro Yano 《Plant biotechnology journal》2016,14(4):1095-1098
Agriculture is now facing the ‘perfect storm’ of climate change, increasing costs of fertilizer and rising food demands from a larger and wealthier human population. These factors point to a global food deficit unless the efficiency and resilience of crop production is increased. The intensification of agriculture has focused on improving production under optimized conditions, with significant agronomic inputs. Furthermore, the intensive cultivation of a limited number of crops has drastically narrowed the number of plant species humans rely on. A new agricultural paradigm is required, reducing dependence on high inputs and increasing crop diversity, yield stability and environmental resilience. Genomics offers unprecedented opportunities to increase crop yield, quality and stability of production through advanced breeding strategies, enhancing the resilience of major crops to climate variability, and increasing the productivity and range of minor crops to diversify the food supply. Here we review the state of the art of genomic‐assisted breeding for the most important staples that feed the world, and how to use and adapt such genomic tools to accelerate development of both major and minor crops with desired traits that enhance adaptation to, or mitigate the effects of climate change. 相似文献