リグノセルロースの酵素糖化反応の活性化に関する研究

CHPTER1 Introduction / CHPTER2 Screening the suitable wood rotting fungi for corn stover pretreatment / CHPTER3 Physical and chemical characterizations of corn stover pretreated by G. trabeum KU-41 / CHPTER4 Screening the microorganism with high activity of β-glucosidases / CHPTER5 Strain Identification / CHPTER6 Effect of different carbon source on β-glucosidases production in F. proliferatum NBRC109045 / CHPTER7 Partly purification of a glucose-tolerant β-glucosidase from F. proliferatum NBRC109045 / Conclusion / References / AcknowledgeSubmitted by 愛 遠藤 ([email protected]) on 2012-10-09T02:58:23Z No. of bitstreams: 2 agr668.pdf: 3506575 bytes, checksum: 1fb28bde55959d5ea8d12e4973b86ede (MD5) agr668_abstruct.pdf: 118285 bytes, checksum: 6cddd4ec0f70b9238e030b238baa4ed7 (MD5)Made available in DSpace on 2012-10-09T02:58:23Z (GMT). No. of bitstreams: 2 agr668.pdf: 3506575 bytes, checksum: 1fb28bde55959d5ea8d12e4973b86ede (MD5) agr668_abstruct.pdf: 118285 bytes, checksum: 6cddd4ec0f70b9238e030b238baa4ed7 (MD5) Previous issue date: 2012-09-24主1-参1森林資源The bioconversion of renewable resources, especially lignocellulosic residues, into useful chemicals and fuel ethanol is a worldwide challenge for biotechnology. Lignocellulose bio-refining generally involves three main steps: pretreatment, enzymatic hydrolysis, and fermentation. Commercialization of bio-ethanol is hindered by the high cost of pretreatment process and high cost of cellulase enzymes required for lignocellulose hydrolysis. Therefore, choose a suitable pretreatment method and screen the fungi or bacterial with high-efficient hydrolytic multienzyme system are the necessary approach for successful commercialization. In this study, we set forth the methods that enhancing the enzymatic hydrolysis of lignocellulose in two directions: (1) Choose biological pretreatment method that using brown-rot fungus Gloeophyllum trabeum KU-41 to pretreat corn stover for efficient hydrolysis. To gain a deeper understanding of the mechanisms of brown-rot fungus pretreatment, the fungal-pretreated corn stover was evaluated in detail, including the lignin and structural carbohydrate contents, cellulose crystallinity, initial adsorption capacity of cellulase, SEM and specific surface area. G. trabeum has an efficient degradation system, and the results indicated that the conversion of cellulose to glucose increases as the accessibility of cellulose increases due to the partial removal of xylan and the structure breakage of the cell wall. (2) To isolate and screen microorganisms to produce considerable quantities of β-glucosidases. A potent β-glucosidases-producing fungus SIID11460 was isolated and identified as Fusarium proliferatum. Under optimized conditions, F. proliferatum SIID11460 produces β-glucosidases with high specific activity (16.5 U/mg-protein). Moreover, a new method was built up that combines zymogram, gel purification and SDS-PAGE. Using this method, it was proved that F. proliferatum SIID11460 could express varied β-glucosidases in respond to varied carbon sources. The present research might be a promotion for bio-ethanol production. G. trabeum was applied to pretreat corn stover with enhancing saccharification significantly. This pretreatment method can be further explored as an alternative to the thermochemical pretreatment method. β-glucosidases produced by F. proliferatum SIID11460 with high catalytic activity could apply for hydrolysis of lignocellulose for bio-ethanol production

Index of Mind

Li Xiangming: Index of Mind, is an exhibition focuses on the artist’s recent productions and his contemplation of “object” and “its relations.” The collection demonstrates the artist’s freewill of creation and his hope of conveying his care and bring attention to the group of people who has been neglected in the trace of history. Li has not only been dedicated to express the living condition and mental state of a certain region, though to express the life and the will to live shared by all through his use of ordinary materials and subject matters with collective memories. This exhibition could be considered as an extension of Li’s Tuyu (native/local language) series in 2005 and his concept of the “populism aesthetic” and to be more specific, the “patch aesthetics” as indicated by art critic Jia Fangzhou. As one of the first few artists who wanted to create Chinese local abstraction, a form that is distinct from the Western with Chinese sprits, Li has been always contemplate the true meaning of creating art with local culture. Li has always had a question in his mind – how to get to know China? To truly understand the nation, he believes one must understand its native land, in other words the country side that is composed of a group of people representing the majority of civilians in a large agricultural country and is the group that brings most of the labor value in this country. Through this collection of works, the artist sincerely hopes to evoke memory of the life, memory of culture and memory history that seems to have been flattened and vanished in time. He also wishes to awaken people’s deep excitement and enter stages of introspection and reflection thought such serious and heavy theme. Li Xiangming has been focused on utilizing ready-made objects collected from his hometown in Hebei and other rural areas in China. He is dedicated in exploring the relationship between his found objects and meaning he sees behind these ready-made objects: culturally, livelihood, historically, all hovering in his mind. Patchwork for him symbolizes the inheritance of art, culture and history, as well as the aesthetic consciousness of an older generation. His choice of using rags or cloth with patches on patches rather than new cloth reveals the notion of social critical consciousness. These rags and discarded ordinary objects can be considered as an irony of poverty and laggard in Chinese society. Incorporating low class culture into elite culture could also be a statement of teasing art itself with these rags, sacks and clothes collected by the artist as documentations of underclass’s suffering and arduousness, and the fact of their life is constantly being commercialized, dominated and unfamiliarized and the absurdity sublime and judgement of history. Li Xiangming’s art touches the “unconsciousness” of Chinese people, which refers to the obscured general public. Through this collection of work, Li expresses more of life suffering and humble solicitude and wanting to evoke feelings that touches the bottom of life. The display of the entire exhibition will demonstrate audiences with a narrative of things we’ve overlooked in life through various forms including collages, installations and screen projection

Personalized Privacy Protection Based on Space Grid in Mobile Crowdsensing

The rapid proliferation of handheld intelligent devices and the advent of 5G technology have brought about convenient and fast services for people. In perception-oriented application services, participating users will upload sensitive mobile data in order to obtain benefits. While devising privacy protection strategies to ensure data security, it is crucial to accomplish task perception related to data collection to the fullest extent possible. To address this challenge, this paper proposes a personalized data privacy protection algorithm based on an adaptive dynamic adjustment grid and the minimum wage task allocation strategy. According to the different levels of users’ needs for privacy protection, combined with the privacy budget allocation strategy, we design a different-level differential privacy protection mechanism and consider the reward mechanism in task allocation to balance the effectiveness and security of the location data uploaded by users. Experiments show that the strategy proposed in this paper can not only protect the data but also enable users to freely choose the level of privacy protection

The pretreatment of corn stover with <it>Gloeophyllum trabeum</it> KU-41 for enzymatic hydrolysis

Abstract Background Pretreatment is an essential step in the enzymatic hydrolysis of biomass for bio-ethanol production. The dominant concern in this step is how to decrease the high cost of pretreatment while achieving a high sugar yield. Fungal pretreatment of biomass was previously reported to be effective, with the advantage of having a low energy requirement and requiring no application of additional chemicals. In this work, Gloeophyllum trabeum KU-41 was chosen for corn stover pretreatment through screening with 40 strains of wood-rot fungi. The objective of the current work is to find out which characteristics of corn stover pretreated with G. trabeum KU-41 determine the pretreatment method to be successful and worthwhile to apply. This will be done by determining the lignin content, structural carbohydrate, cellulose crystallinity, initial adsorption capacity of cellulase and specific surface area of pretreated corn stover. Results The content of xylan in pretreated corn stover was decreased by 43% in comparison to the untreated corn stover. The initial cellulase adsorption capacity and the specific surface area of corn stover pretreated with G. trabeum were increased by 7.0- and 2.5-fold, respectively. Also there was little increase in the cellulose crystallinity of pretreated corn stover. Conclusion G. trabeum has an efficient degradation system, and the results indicated that the conversion of cellulose to glucose increases as the accessibility of cellulose increases due to the partial removal of xylan and the structure breakage of the cell wall. This pretreatment method can be further explored as an alternative to the thermochemical pretreatment method.</p

Light and oxygen facilitating the directly treatment food wastewater and poly-β-hydroxybutyrate, 5-aminolevulinic acid, pigment productions by Rubrivivax gelatinosus

Rubrivivax gelatinosus has the advantage of using wastewater to realize biomass recovery. However, they still cannot be applied large scale because they cannot directly treat the wastewater containing macromolecular organics. Thus, this article investigated the effects of light–oxygen conditions on R. gelatinosus by directly recycling wastewater containing macromolecular organics to produce biomass, poly-β-hydroxybutyrate (PHB), 5-aminolevulinic acid (5-ALA), and pigment. Results showed that R. gelatinosus directly treated the macromolecule organic (soybean protein and starch) wastewaters and achieved biomass recovery under light–anaerobic and light–micro-oxygen in six conditions. Chemical oxygen demand, protein, and starch removals for two wastewaters all reached above 70%. Renewable bio-resources such as biomass, PHB, 5-ALA, and pigment production were 10 times the initial content. Theoretical analysis indicated that light activated the synthesis of protease and amylase. However, oxygen concentration decided the number of enzymes. When oxygen was at micro-oxygen or anaerobic, the aforementioned expression and synthesis were conducted. In summary, this study expanded the viewpoint ignored by traditional theory. It was realized that R. gelatinosus directly treated wastewater and accumulated nutrients (biomass, PHB, pigment, and 5-ALA) for recycling, which reduced the secondary pollution of excess sludge into the environment. HIGHLIGHTS This study expands the traditional theory of Rubrivivax gelatinosus directly un-degrading wastewater.; R. gelatinosus had the potential to directly degrade wastewaters, and recycled biomass under light–anaerobic.; Light affected the synthesis of protease and amylase in R. gelatinosus.; Oxygen concentration affected the number of enzymes.