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911.
Okada H Fukushi E Yamamori A Kawazoe N Onodera S Kawabata J Shiomi N 《Carbohydrate research》2011,346(16):2633-2637
Fermented beverage of plant extracts was prepared from the extracts of approximately 50 types of vegetables and fruits. Natural fermentation was carried out mainly by lactic acid bacteria (Leuconostoc spp.) and yeast (Zygosaccharomyces spp. and Pichia spp.). Two oligosaccharides containing an α-fructofuranoside linkage were detected in this beverage and isolated using carbon-Celite column chromatography and preparative HPLC. The structural confirmation of the saccharides was determined by methylation analysis, MALDI-TOF-MS, and NMR measurements. These saccharides were identified as α-D-fructofuranosyl-(2→6)-D-glucopyranose, which was isolated from a natural source for the first time, and a novel saccharide β-D-fructopyranosyl-(2→6)-α-D-fructofuranosyl-(2?1)-α-D-glucopyranoside. 相似文献
912.
913.
Sandra C. Lindstrom Juliet Brodie Michael D. J. Lynch Mi Sook Hwang Han‐Gu Choi Masahiko Miyata Norio Kikuchi Mariana C. Oliveira Tracy Farr Chris Neefus Agnes Mols‐Mortensen Daniela Milstein Kirsten M. Müller 《Journal of phycology》2011,47(5):1131-1151
The red algal order Bangiales has been revised as a result of detailed regional studies and the development of expert local knowledge of Bangiales floras, followed by collaborative global analyses based on wide taxon sampling and molecular analyses. Combined analyses of the nuclear SSU rRNA gene and the plastid RUBISCO LSU (rbcL) gene for 157 Bangiales taxa have been conducted. Fifteen genera of Bangiales, seven filamentous and eight foliose, are recognized. This classification includes five newly described and two resurrected genera. This revision constitutes a major change in understanding relationships and evolution in this order. The genus Porphyra is now restricted to five described species and a number of undescribed species. Other foliose taxa previously placed in Porphyra are now recognized to belong to the genera Boreophyllum gen. nov., Clymene gen. nov., Fuscifolium gen. nov., Lysithea gen. nov., Miuraea gen. nov., Pyropia, and Wildemania. Four of the seven filamentous genera recognized in our analyses already have generic names (Bangia, Dione, Minerva, and Pseudobangia), and are all currently monotypic. The unnamed filamentous genera are clearly composed of multiple species, and few of these species have names. Further research is required: the genus to which the marine taxon Bangia fuscopurpurea belongs is not known, and there are also a large number of species previously described as Porphyra for which nuclear SSU ribosomal RNA (nrSSU) or rbcL sequence data should be obtained so that they can be assigned to the appropriate genus. 相似文献
914.
915.
Bioelectrochemical system accelerates microbial growth and degradation of filter paper 总被引:1,自引:0,他引:1
Sasaki K Hirano S Morita M Sasaki D Matsumoto N Ohmura N Igarashi Y 《Applied microbiology and biotechnology》2011,89(2):449-455
Bioelectrochemical reactors (BERs) with a cathodic working potential of −0.6 or −0.8 V more efficiently degraded cellulosic
material, i.e., filter paper (57.4–74.1% in 3 days and 95.9–96.3% in 7 days) than did control reactors without giving exogenous
potential (15.4% in 3 days and 64.2% in 7 days). At the same time, resultant conversions to methane and carbon dioxide in
cathodic working chamber of BERs by application of electrochemical reduction in 3 days of operation were larger than control
reactors. However, cumulative methane production in cathodic BERs was similar to those in control reactors after 7 days of
operation. Microscopic observation and 16S rRNA gene analysis showed that microbial growth in the entire consortium was higher
after 2 days of operation of cathodic BERs as compared with the control reactors. In addition, the number of methanogenic
16S rRNA gene copies in cathodic BERs was higher than in control reactors. Moreover, archaeal community structures constructed
in cathodic BERs consisted of hydrogenotrophic methanogen-related organisms and differed from those in control reactors after
2 days of operation. Specifically, the amount of Methanothermobacter species in cathodic BERs was higher within archaeal communities than in those control reactors after 2 days of operation.
Electrochemical reduction may be effective for accelerating microbial growth in the start-up period and thereby increasing
microbial treatment of cellulosic waste and methane production. 相似文献
916.
Deferoxamine (DFO), an FDA-approved iron chelator used for treatment of iron poisoning, affects bacteria as iron availability is intimately connected with growth and several virulence determinants. However, little is known about the effect on oral pathogens. In this study, the effect of DFO on Porphyromonas gingivalis, a major periodontopathogen which has an essential growth requirement for hemin (Fe(3+)-protoporphyrin IX), was evaluated. The viability of P. gingivalis W83 was not affected by 0.06-0.24 mM DFO, whereas the doubling time of the bacterium was considerably prolonged by DFO. The inhibitory effect was evident at earlier stages of growth and reduced by supplemental iron. UV-visible spectra using the pigments from P. gingivalis cells grown on blood agar showed that DFO inhibited μ-oxo bisheme formation by the bacterium. DFO decreased accumulation and energy-driven uptake of hemin by P. gingivalis. Antibacterial effect of H(2)O(2) and metronidazole against P. gingivalis increased in the presence of DFO. Collectively, DFO is effective for hemin deprivation in P. gingivalis suppressing the growth and increasing the susceptibility of the bacterium to other antimicrobial agents such as H(2)O(2) and metronidazole. Further experiments are necessary to show that DFO may be used as a therapeutic agent for periodontal disease. 相似文献
917.
We examined the geographic distributions and phylogenetic relationships of bisexual and unisexual (parthenogenetic) forms of the weevil Scepticus insularis on Hokkaido Island, northern Japan. Unisexual beetles were widespread throughout Hokkaido, whereas bisexuals were found only in three remote areas. Bisexuals (females and males) and unisexual females occurred sympatrically in two areas. We determined nucleotide sequences for part of the mitochondrial NADH dehydrogenase subunit 2 (ND2; 633 bp) gene for 104 individuals, and for part of the nuclear internal transcribed spacer region 2 (ITS2; 360 bp) for 91 individuals. In an ND2 gene tree, haplotypes of S. insularis fell into two distinct clades (A and B), which were genetically differentiated from one another by 9.1% nucleotide sequence divergence. Haplotypes of females identified as unisexual were all in clade A, whereas those of females identified as bisexual belonged to clade B. Haplotypes of males were in clade B, except for two males having a clade-A haplotype. Circumstantial evidence suggests that these two males were produced by unisexual females. The ND2 tree suggests that the current unisexual form of S. insularis on Hokkaido was of a single origin. In contrast, a gene tree for ITS2 haplotypes show no clear divergence between the two modes of reproduction, with two major haplotypes shared by unisexual females, bisexual females, and males. This incongruence between the nuclear and mitochondrial phylogenies may be attributable to occasional gene flow between the unisexual and bisexual lineages through males occasionally produced by unisexual females, but our results do not exclude the possibility that the two lineages share polymorphic ancestral ITS2 haplotypes. 相似文献
918.
The interaction between lecithin liposomes and acid clay was investigated to clarify the mechanism for liposome adsorption to the clay. It was found that the multilamellar vesicular structure of the liposomes was broken as a result of primary adsorption. The acid clay particles aggregated and were eventually covered by the lecithin layer structure. In the case of kaolin, on the other hand, the liposomes were weakly adsorbed to the clay and maintained the vesicular structure. The amount of primary adsorption to the clay surface, which was estimated from the adsorption isotherm, was more for acid clay than for kaolin, and the total amount adsorbed to the acid clay was also more than to kaolin. This result can be explained by the much higher density of the negative charge on the acid clay surface than that for kaolin. The liposomes are therefore considered to be adsorbed to the acid clay mainly by the choline positive charge residing at the end of the lecithin molecule, although this is of no net charge as a whole. 相似文献
919.
Hiroshi Horibe Masashi Murakami Koichiro Iohara Yuki Hayashi Norio Takeuchi Yoshifumi Takei Kenichi Kurita Misako Nakashima 《PloS one》2014,9(5)
Insights into the understanding of the influence of the age of MSCs on their cellular responses and regenerative potential are critical for stem cell therapy in the clinic. We have isolated dental pulp stem cells (DPSCs) subsets based on their migratory response to granulocyte-colony stimulating factor (G-CSF) (MDPSCs) from young and aged donors. The aged MDPSCs were efficiently enriched in stem cells, expressing high levels of trophic factors with high proliferation, migration and anti-apoptotic effects compared to young MDPSCs. In contrast, significant differences in those properties were detected between aged and young colony-derived DPSCs. Unlike DPSCs, MDPSCs showed a small age-dependent increase in senescence-associated β-galactosidase (SA-β-gal) production and senescence markers including p16, p21, Interleukin (IL)-1β, -6, -8, and Groα in long-term culture. There was no difference between aged and young MDPSCs in telomerase activity. The regenerative potential of aged MDPSCs was similar to that of young MDPSCs in an ischemic hindlimb model and an ectopic tooth root model. These results demonstrated that the stem cell properties and the high regenerative potential of MDPSCs are independent of age, demonstrating an immense utility for clinical applications by autologous cell transplantation in dental pulp regeneration and ischemic diseases. 相似文献
920.
Jun-ichi Suzuki Yasushi Imai Mieko Aoki Daishi Fujita Norio Aoyama Yuko Tada Kouji Wakayama Hiroshi Akazawa Yuichi Izumi Mitsuaki Isobe Issei Komuro Ryozo Nagai Yasunobu Hirata 《PloS one》2014,9(4)