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Isolation and characterization of predominant microorganisms during decomposition of waste materials in a field-scale composter 总被引:2,自引:0,他引:2
Pedro MS Haruta S Nakamura K Hazaka M Ishii M Igarashi Y 《Journal of Bioscience and Bioengineering》2003,95(4):368-373
A self-heating field-scale composter treating agro-industrial wastes within a period of 30 d was analyzed by denaturing gradient gel electrophoresis (DGGE) (Pedro et al., J. Biosci. Bioeng., 91, 159-165, 2001). Three major bands were derived from Propionibacterium acnes, Methylobacterium mesophilicum or M. radiotolerans, and Bacillus thermocloacae. Strains MSP09A and MSP06G with close affiliation to P. acnes and B. thermocloacae, respectively, were successfully isolated. Based on quantitative-PCR results, the relative population of MSP09A increased towards the end of the composting process (mesophilic stage) while MSP06G seemed to predominate during the middle period (thermophilic stage). These results correlated highly with their growth temperatures. MSP09A and MSP06G had different metabolic profiles which were largely affected by culture conditions. MSP09A was able to utilize large complex molecules of lipids and proteins. An interspecies relationship in terms of metabolites such as propionic acid was expected between the two microorganisms. 相似文献
94.
Kitamoto N Kato Y Ohnaka T Yokota M Tanaka T Tsuji K 《Journal of food protection》2003,66(10):1822-1831
In this study, the bactericidal effects of Japanese alkaline foods on food-poisoning bacteria were evaluated. Konjac is an alkaline food soaked in calcinated calcium (the pH of konjac fluid ranges from 11.42 to 12.53). Konjac fluids completely inactivated Escherichia coli, enterohemorrhagic E. coli O157:H7 and E. coil O26:H9, Salmonella Enteritidis, Vibrio parahemolyticus. and Staphylococcus aureus. The initial level of 6 log CFU/ml dramatically decreased after incubation with konjac fluid, and no viable gram-negative bacterium cells could be detected within 1 to 2 days and no viable S. aureus cells could be detected within 3 to 5 days. On the other hand, treatment with konjac fluid was also effective in reducing levels of spore-forming bacteria (Bacillus subtilis, Bacillus cereus, Clostridium perfringens, and Clostridium botulinum type E and type A). At least a 4-log reduction of spore-forming bacteria was obtained in konjac fluid within 7 to 14 days. Vegetative cells were more susceptible to konjac fluid than spores were. When the initial cell count was 6 log CFU/ml, a few surviving spores remained for 60 to 90 days, but no spores could be detected after 120 days. When the initial count of spore-forming bacteria was 3 to 4 log CFU/ml, the cells considered vegetative were completely inactivated within I to 3 days. Repeated treatment with konjac fluid caused complete inactivation of spores in less than 1 to 3 days. Our studies indicate that konjac fluid, which has a long history of use in food, will control food-poisoning bacterial contamination during the production or preservation of konjac and other foods and has a preventive effect on bacteria that can cause severe disease at uniquely low levels. 相似文献
95.
Fang S Wang L Yang P Meng L Komori M Kubo A 《Journal of the Optical Society of America. A, Optics, image science, and vision》2011,28(4):590-595
We put forward a plan of improving the oblique-incidence optical interferometric system applied in the measurement of tooth flanks of an involute spur gear in order to expand its capability to measure an involute helical gear. On the basis of the features of an involute helical tooth flank, we discuss how to realize the parallelism between the optical axis of the object arm of the optical system and the straight lines constructing the involute helical tooth flank. This parallelism helps the optical system produce an interference fringe pattern as clear as the one of an involute spur gear [Appl. Opt.49, 6409 (2010).]. A numerical simulation is then performed to examine the correctness of the improvement. During simulating, we unify the equation of difference tooth flanks by means of importing two parameters in relation to the left or right side of a tooth flank and the helical direction of teeth, respectively. Finally, the actual experiment is fulfilled through the real optical system built on an optical table. The simulation and experiment results verify the correctness and feasibility of the proposed improvement. 相似文献
96.
Iio K Okada Y Ishikura M 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2011,52(3):190-193
Fucoxanthin-containing oil extracted from microalga, Chaetoseros sp., was subjected to genotoxicity studies, the bacterial reverse mutation test and the micronucleus test in mice. The number of revertant colonies in fucoxanthin oil-treated plates of all strains tested was less than twice the number of colonies in the negative control, regardless of the presence of the metabolic activator in the bacterial reverse mutation test. In the micronucleus test, 500, 1,000, 2,000 mg/kg body weight of fucoxanthin oil was administered orally to mice. There was no significant increase in micronucleus frequency in bone marrow cells. These results suggest that fucoxanthin oil does not exhibit genotoxicity. 相似文献
97.
98.
Yuichi Setsuhara Ken Cho Masaharu Shiratani Makoto Sekine Masaru Hori 《Thin solid films》2010,518(22):6492-6726
Plasma-polymer interactions have been investigated using atomic force microscopy (AFM) and x-ray photoelectron spectroscopy (XPS) of polyethyleneterephthalate (PET) films, which have been exposed to argon plasmas driven by low-inductance antenna modules as a parameter of ion energy. The AFM images indicated that the argon plasma exposure exhibited a significant change in surface roughness. The XPS analyses suggested that the degradation of chemical bonding structure and/or bond scission of PET could be effectively suppressed in the plasma exposures with ion energies below 6 eV. However, significant degradations of O = C-O bond, C-O bond and phenyl group were observed with increasing ion energy above 6 eV. 相似文献
99.
Tadao Shibuya Masahiro Yoshinaka Futoshi Utsuno Kazuyoshi Inoue Jung J. Kim Masaaki Obata 《Thin solid films》2010,518(11):3008-3011
The electronic structural analysis of the conductive transparent films was carried out using bulk sensitive hard X-ray photoelectron spectroscopy (HAXPES). The In2O3-ZnO film has amorphous structure before and after annealed, and the conduction band spectrum around Fermi level showed the similar spectra with that of as-deposited amorphous In2O3 film. In these amorphous films, the conduction band minimum locates at the deeper level than the crystalline In2O3 film. The electronic state which comes from randomness of amorphous structure possibly exists around this level or below. These electrons are expected to act as scattering center. We concluded that the electron mobility depends on the density of this electronic state. 相似文献
100.