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Engineering of oxygen vacancy and bismuth cluster assisted ultrathin Bi_(12)O_(17)Cl_(2)nanosheets with efficient and selective photoreduction of CO_(2)to CO 被引量:2
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作者 Meili Guan Ni Lu +7 位作者 Xuan Zhang Qiuwan Wang Jian Bao Guiye Chen Hao Yu Huaming Li Jiexiang Xia Xuezhong Gong 《Carbon Energy》 SCIE EI CAS CSCD 2024年第4期1-11,共11页
The photocatalytic conversion of CO_(2)into solar‐powered fuels is viewed as a forward‐looking strategy to address energy scarcity and global warming.This work demonstrated the selective photoreduction of CO_(2)to C... The photocatalytic conversion of CO_(2)into solar‐powered fuels is viewed as a forward‐looking strategy to address energy scarcity and global warming.This work demonstrated the selective photoreduction of CO_(2)to CO using ultrathin Bi_(12)O_(17)Cl_(2)nanosheets decorated with hydrothermally synthesized bismuth clusters and oxygen vacancies(OVs).The characterizations revealed that the coexistences of OVs and Bi clusters generated in situ contributed to the high efficiency of CO_(2)–CO conversion(64.3μmol g^(−1)h^(−1))and perfect selectivity.The OVs on the facet(001)of the ultrathin Bi_(12)O_(17)Cl_(2)nanosheets serve as sites for CO_(2)adsorption and activation sites,capturing photoexcited electrons and prolonging light absorption due to defect states.In addition,the Bi‐cluster generated in situ offers the ability to trap holes and the surface plasmonic resonance effect.This study offers great potential for the construction of semiconductor hybrids as multiphotocatalysts,capable of being used for the elimination and conversion of CO_(2)in terms of energy and environment. 展开更多
关键词 Bi cluster Bi_(12)O_(17)Cl_(2)nanosheet oxygen vacancy photocatalytic CO_(2)reduction
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Exploration and Practice of Biological Engineering Experiment Reform
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作者 He Jingting 《生物技术世界》 2013年第8期92-92,共1页
Reform of experimental teaching should be the integration of relevant experimental courses,rational use of laboratory equipment to share resources and improve equipment utilization.Experimental results showed that the... Reform of experimental teaching should be the integration of relevant experimental courses,rational use of laboratory equipment to share resources and improve equipment utilization.Experimental results showed that the teaching reform significantly improved the utilization of laboratories and equipment,and significantly enhanced the practical ability of students. 展开更多
关键词 BIOENGINEERING EXPERIMENTAL TEACHING REFORM
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Breakthrough of Carbon-Ash Recalcitrance in Hydrochar via Molten Carbonate:Engineering Mineral-Rich Biowaste Toward Sustainable Platform Carbon Materials
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作者 Zihan Wang Leli Zhang +1 位作者 Yuanhui Zhang Zhidan Liu 《Engineering》 SCIE EI CAS CSCD 2024年第5期167-177,共11页
The function-led design of porous hydrochar from mineral-rich biowaste for environmental applications inevitably suffers from carbon-ash recalcitrance.However,a method to alter the original carbon skeleton with ash re... The function-led design of porous hydrochar from mineral-rich biowaste for environmental applications inevitably suffers from carbon-ash recalcitrance.However,a method to alter the original carbon skeleton with ash remains elusive and hinders the availability of hydrochar.Herein,we propose a facile strategy for breaking the rigid structure of carbon-ash coupled hydrochar using phase-tunable molten carbonates.A case system was designed in which livestock manure and NaHCO3 were used to prepare the activated hydrochar,and NH3 served as the target contaminant.Due to the redox effect,we found that organic fractions significantly advanced the melting temperature of Na2CO3 below 800℃.The Na species steadily broke the carbon-ash interaction as the thermal intensity increased and transformed inorganic constituents to facilitate ash dissolution,rebuilding the hydrochar skeleton with abundant hierarchical channels and active defect edges.The surface polarity and mesopore distribution collectively governed the five cycles NH3 adsorption attenuation process.Manure hydrochar delivered favorable potential for application with a maximum overall adsorption capacity of 100.49 mg·g^(-1).Integrated spectroscopic characterization and theoretical computations revealed that incorporating NH3 on the carbon surface could transfer electrons to chemisorbed oxygen,which promoted the oxidation of pyridine-N during adsorption.This work offers deep insight into the structure function correlation of hydrochar and inspires a more rational design of engineered hydrochar from high-ash biowaste. 展开更多
关键词 Hydrochar Livestock manure Ammonia adsorption DEASHING Oxygen activation
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AI in Chemical Engineering: A New Chapter of Innovation
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作者 Qilong Ren 《Engineering》 SCIE EI CAS CSCD 2024年第8期1-2,共2页
The integration of artificial intelli-gence(AI)into chemical engineering marks a transformative era,redefin-ing traditional methodologies with AI-driven approaches.AI has emerged as a powerful ally in tackling complex... The integration of artificial intelli-gence(AI)into chemical engineering marks a transformative era,redefin-ing traditional methodologies with AI-driven approaches.AI has emerged as a powerful ally in tackling complex problems once considered insur-mountable.As chemical engineering grapples with increasingly complex systems and stringent sustainability targets,AI sets the stage for a new generation of solutions. 展开更多
关键词 MOUNT AI emerged
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The metabolic profiling of Chinese yam fermented by Saccharomyces boulardii and the biological activities of its ethanol extract in vitro
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作者 Xue Li Yiwen Shao +7 位作者 Limin Hao Qiaozhen Kang Xiaolong Wang Jiaqing Zhu Changcheng Zhao Yanling Shi Jike Lu Juanjuan Yi 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2718-2726,共9页
Chinese yam(Dioscorea opposita Thunb.),as one of the medicinal and edible homologous plants,is rich in various nutrients and functional factors.In this study,Chinese yam fermented by Saccharomyces boulardii was perfor... Chinese yam(Dioscorea opposita Thunb.),as one of the medicinal and edible homologous plants,is rich in various nutrients and functional factors.In this study,Chinese yam fermented by Saccharomyces boulardii was performed to investigate its bioactive components and metabolic profile.And then,the main bioactive components and biological activities of fermented Chinese yam ethanol extract(FCYE)were evaluated.Results showed that there were 49 up-regulated metabolites and 52 down-regulated metabolites in fermented Chinese yam compared to unfermented Chinese yam.Besides,corresponding metabolic pathways analysis initially revealed that the distribution of bioactive substances was concentrated on alcoholsoluble small molecular substances.Ulteriorly,the total polyphenol content and the total flavonoid content in FCYE were significantly increased,and the corresponding antioxidant and immunomodulatory activities in vitro were also significantly enhanced.Our study provided a new reference for the comprehensive utilization of Chinese yam and laid a theoretical foundation for the development and application of natural probiotic-fermented products. 展开更多
关键词 Chinese yam Saccharomyces boulardii METABOLITES ANTIOXIDANT IMMUNOMODULATION
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Bioactive compounds in Hericium erinaceus and their biological properties:a review
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作者 Yue Qiu Genglan Lin +4 位作者 Weiming Liu Fuming Zhang Robert J.Linhardt Xingli Wang Anqiang Zhang 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期1825-1844,共20页
Hericium erinaceus is a nutritious edible and medicinal fungi,rich in a variety of functional active ingredients,with various physiological functions such as antioxidation,anticancer,and enhancing immunity.It is also ... Hericium erinaceus is a nutritious edible and medicinal fungi,rich in a variety of functional active ingredients,with various physiological functions such as antioxidation,anticancer,and enhancing immunity.It is also effective in protecting the digestive system and preventing neurodegenerative diseases.In this review paper,we summarize the sources,structures and efficacies of the main active components in H.erinaceus fruiting body,mycelium,and culture media,and update the latest research progress on their biological activities and the related molecular mechanisms.Based on this information,we provide detailed challenges in current research,industrialization and information on the active ingredients of H.erinaceus.Perspectives for future studies and new applications of H.erinaceus are proposed. 展开更多
关键词 Hericium erinaceus Bioactive compounds Biological activities ANTIOXIDATION NEUROPROTECTION IMMUNOREGULATION
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Exploration on Teaching Reform of Synthetic Biology Course Based on the New Engineering Concept
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作者 Jie CHENG Shunyang HU +3 位作者 Fangkun YU Jiamin ZHANG Bingliang LIU Yin ZHANG 《Agricultural Biotechnology》 2024年第3期86-89,共4页
Synthetic biology is a new frontier of life science,which aims to design,transform and even synthesize organisms with engineering design concept.Doing a good job in the teaching of"synthetic biology"is of gr... Synthetic biology is a new frontier of life science,which aims to design,transform and even synthesize organisms with engineering design concept.Doing a good job in the teaching of"synthetic biology"is of great significance to the cultivation and reserve of biotechnology professionals in China,and also has an important impact on students' employment competitiveness.Under the background of"new engineering",the course reform of"synthetic biology"was carried out in terms of the construction of teaching staff,teaching methods,students' participation and the innovation of course content,and specific reform suggestions were put forward,hoping to effectively promote the sustainable development of"synthetic biology"and effectively improve the quality of education. 展开更多
关键词 Teaching reform Synthetic biology Teaching innovation Teaching methods
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Advancements and Challenges in Organic–Inorganic Composite Solid Electrolytes for All‑Solid‑State Lithium Batteries
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作者 Xueyan Zhang Shichao Cheng +4 位作者 Chuankai Fu Geping Yin Liguang Wang Yongmin Wu Hua Huo 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期46-97,共52页
To address the limitations of contemporary lithium-ion batteries,particularly their low energy density and safety concerns,all-solid-state lithium batteries equipped with solid-state electrolytes have been identified ... To address the limitations of contemporary lithium-ion batteries,particularly their low energy density and safety concerns,all-solid-state lithium batteries equipped with solid-state electrolytes have been identified as an up-and-coming alternative.Among the various SEs,organic–inorganic composite solid electrolytes(OICSEs)that combine the advantages of both polymer and inorganic materials demonstrate promising potential for large-scale applications.However,OICSEs still face many challenges in practical applications,such as low ionic conductivity and poor interfacial stability,which severely limit their applications.This review provides a comprehensive overview of recent research advancements in OICSEs.Specifically,the influence of inorganic fillers on the main functional parameters of OICSEs,including ionic conductivity,Li+transfer number,mechanical strength,electrochemical stability,electronic conductivity,and thermal stability are systematically discussed.The lithium-ion conduction mechanism of OICSE is thoroughly analyzed and concluded from the microscopic perspective.Besides,the classic inorganic filler types,including both inert and active fillers,are categorized with special emphasis on the relationship between inorganic filler structure design and the electrochemical performance of OICSEs.Finally,the advanced characterization techniques relevant to OICSEs are summarized,and the challenges and perspectives on the future development of OICSEs are also highlighted for constructing superior ASSLBs. 展开更多
关键词 Composite solid electrolytes Inorganic filler Interfacial stability Li-ion conduction mechanism Characterization techniques
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Optimization of Two-species Whole-cell Immobilization System Constructed with Marine-derived Fungi and Its Biological Degradation Ability 被引量:5
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作者 陈慧英 王明霞 +1 位作者 沈煜斌 姚善泾 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第2期187-192,共6页
Mycelia pellet formed spontaneously in the process of cultivation was exploited as a biological carrier for whole-cell immobilization due to its unique structural characteristic. An innovative two-species whole-cell i... Mycelia pellet formed spontaneously in the process of cultivation was exploited as a biological carrier for whole-cell immobilization due to its unique structural characteristic. An innovative two-species whole-cell im- mobilization system was achieved by inoculating the marine-derived fungus Pestalotiopsis sp. J63 spores into cul- ture medium containing another fungus Penicillium janthinellum P1 pre-grown mycelia pellets for 2 days without any pretreatment. In order to evaluate the biological degradation capacity of this novel constructed immobilization system, the immobilized pellets were applied to treat paper mill effluent and decolorize dye Azure B. The use of the constructed immobilization system in the effluent resulted in successful and rapid biodegradation of numerous in- soluble fine fibers. The optimum conditions of immobilized procedure for maximum biodegradation capacity were determined using orthogonal design with biomass of P1 pellets 10 g (wet mass), concentration of J63 spore 2x109 mlq, and immobilization time 2 d. The results demonstrate that immobilized pellets have more than 99% biodegradation capacity in a ten-hour treatment process. The kinetics of biodegradation fits the Michaelis-Menten equation well. Besides, the decolorization capability of immobilized pellets is more superior than that of P1 mycelia pellets. Overall, the present study offers a simple and reproducible way to construct a two-species whole-cell immobiliza- tion system for sewage treatment. 展开更多
关键词 whole-cell immobilization mycelia pellet Pestalotiopsis sp. Penicillium janthinellum biodegradation kinetics biological wastewater treatment
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Harnessing the HDAC–histone deacetylase enzymes,inhibitors and how these can be utilised in tissue engineering 被引量:5
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作者 Liam Lawlor Xuebin B. Yang 《International Journal of Oral Science》 SCIE CAS CSCD 2019年第2期79-89,共11页
There are large knowledge gaps regarding how to control stem cells growth and differentiation.The limitations of currently available technologies,such as growth factors and/or gene therapies has led to the search of a... There are large knowledge gaps regarding how to control stem cells growth and differentiation.The limitations of currently available technologies,such as growth factors and/or gene therapies has led to the search of alternatives.We explore here how a cell’s epigenome influences determination of cell type,and potential applications in tissue engineering.A prevalent epigenetic modification is the acetylation of DNA core histone proteins.Acetylation levels heavily influence gene transcription.Histone deacetylase (HDAC) enzymes can remove these acetyl groups,leading to the formation of a condensed and more transcriptionally silenced chromatin.Histone deacetylase inhibitors (HDACis) can inhibit these enzymes,resulting in the increased acetylation of histones,thereby affecting gene expression.There is strong evidence to suggest that HDACis can be utilised in stem cell therapies and tissue engineering,potentially providing novel tools to control stem cell fate.This review introduces the structure/function of HDAC enzymes and their links to different tissue types (specifically bone,cardiac,neural tissues),including the history,current status and future perspectives of using HDACis for stem cell research and tissue engineering,with particular attention paid to how different HDAC isoforms may be integral to this field. 展开更多
关键词 HDAC CAN BE cells gene has led DNA
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Progress of polymer reaction engineering:From process engineering to product engineering 被引量:2
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作者 Pingwei Liu Jigang Du +3 位作者 Yuting Ma Qingyue Wang Khak Ho Lim Bo-Geng Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第10期3-11,共9页
Polymer reaction engineering studies the design,operation,and optimization of reactors for industrial scale polymerization,based on the theory of polymerization kinetics and transfer processes(e.g.,flow,heat and mass ... Polymer reaction engineering studies the design,operation,and optimization of reactors for industrial scale polymerization,based on the theory of polymerization kinetics and transfer processes(e.g.,flow,heat and mass transfer).Although the foundation and development of this discipline are less than80 years,the global production of polymers has exceeded 400 million tons per annum.It demonstrates that polymer reaction engineering is of vital importance to the polymer industry.Along with the matu rity of production processes and market saturation for bulk polymers,emerging industries such as information technology,modern transportation,biomedicine,and new energy have continued to develop.As a result,the research objective for polymer reaction engineering has gradually shifted from maximizing the efficiency of the polymerization process to the precise regulation of high-end product-oriented macro molecules and their aggregation structures,i.e.,from polymer process engineering to polymer product engineering.In this review,the frontiers of polymer reaction engineering are introduced,including the precise regulation of polymer chain structure,the control of primary aggregation structure,and the rational design of polymer products.We narrow down the topic to the polymerization reaction engineering of vinyl monomers.Moreover,the future prospects are provided for the field of polymer reaction engineering. 展开更多
关键词 Controlled polymerization Polymer chainstructure Primary aggregationstructure Rational design Numerical controlmanufacturing
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Engineering cerebral folding in brain organoids 被引量:1
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作者 Glen Scott Yu Huang 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第11期2420-2422,共3页
Valuable implement to the animal neurological models:Neurological diseases remain the largest cause of death and disability.The discovery of effective therapies is chiefly hindered by the lack of realistic neurologica... Valuable implement to the animal neurological models:Neurological diseases remain the largest cause of death and disability.The discovery of effective therapies is chiefly hindered by the lack of realistic neurological models.Unlike other tissues,it is infeasible or unethical to access primary human neural samples in bulk.But animal models often fail to replicate the complex human-specific neuronal factors present in vivo.Conventional in vitro cultures lack native three-dimensional(3D)morphologies,polarity,and receptor expression,as well as tissue-level interactions(J ensen et al.,2018). 展开更多
关键词 CEREBRAL DISEASES
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Research on the Construction and Function of a Chlorophyll Degradation Recombinant Engineering Strain
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作者 Zongcan YANG Zhan ZHANG +3 位作者 Jianbin YE Yufu PENG Xiangzhen LIU Hongxia WANG 《Agricultural Science & Technology》 CAS 2017年第10期1788-1794,共7页
In order to effectively reduce the chlorophyll content in flue-cured tobacco, improve the overall quality of tobacco leaves, chlorophyllase gene was cloned from Arabidopsis thaliana. After the expression of the expres... In order to effectively reduce the chlorophyll content in flue-cured tobacco, improve the overall quality of tobacco leaves, chlorophyllase gene was cloned from Arabidopsis thaliana. After the expression of the expression vector in E. coil, the recombinant engineering strain was obtained. Afterwards, IPTG (isopropy-β-D-thiogalactopyranoside)was used to induce the goal protein, and the chlorophyllase activity of the recombinant engineering strain was measured, so as to investigate its degradation effect on the chlorophyll in the extracts of tobacco leaves. The results were as follows: (1) the amplified chlorophyllase gene At- CLH1 constructed the expression vector pET28a-AtCLH1 successfully, obtaining the recombinant engineering strain; (2) induced under 30 ℃ for 22 h, the strain could well express the recombinant protein AtCLH1 with 0.5 mmol/L IPTG, and the molecular weight was about 35 kDa; (3) the strain showed good chlorophyllase producing capability, and the activity of the produced chlorophyllase could reach up to 24.9 U/mL, which could degrade the chlorophyll in tobacco extract and had a good application prospect in improving the quality of low quality tobacco; (4) based on the results of orthogonal test, the enzyme extract from the strain was added to the tobacco leaf surface, which could make the degradation rate of chlorophyll in the tobacco leaf reach 17.06% under the temperature of 37 ℃ at the humidity of 75% for 48 h; (5) after treated by the enzyme liquid, the test tobacco showed increase in the content of aromatic substances, enhancement of tobacco fragrance quality and amount, significant decrease of offensive odor and irritation, significant improvement of agreeable aftertaste, making the overall sensory quality of the tobacco leaf significantly improved. 展开更多
关键词 Tobacco leaf Degradation of chlorophyll Recombinant Engineering strain Protein expression Activity of chlorophyllase Orthogonal test Aroma substances Sensory quality
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Industrial Biosystems Engineering and Biorefinery Systems
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作者 Shulin Chen 《生物工程学报》 CAS CSCD 北大核心 2008年第6期940-945,共6页
The concept of Industrial Biosystems Engineering (IBsE) was suggested as a new engineering branch to be developed for meeting the needs for science, technology and professionals by the upcoming bioeconomy. With emphas... The concept of Industrial Biosystems Engineering (IBsE) was suggested as a new engineering branch to be developed for meeting the needs for science, technology and professionals by the upcoming bioeconomy. With emphasis on systems, IBsE builds upon the interfaces between systems biology, bioprocessing, and systems engineering. This paper discussed the background, the suggested definition, the theoretical framework and methodologies of this new discipline as well as its challenges and future development. 展开更多
关键词 生物工程 生物系统 生物技术 发展现状
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Cultivation of Innovation Ability of Students in the Discipline of Food Science and Engineering from the Perspective of Engineering Professional Certification
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作者 Weijie ZHANG Haile MA Xinquan SONG 《Asian Agricultural Research》 2017年第2期75-79,82,共6页
Cultivating the top-notch innovative talents is an essential task for connotative construction of higher education.As an applicationoriented discipline,the Discipline of Food Science and Engineering attaches great imp... Cultivating the top-notch innovative talents is an essential task for connotative construction of higher education.As an applicationoriented discipline,the Discipline of Food Science and Engineering attaches great importance to the cultivation of innovation ability of college students.For a long time,however,the discipline education has problems of the inverted teaching subject position,weak coordination ability and single practice mode.The support for the cultivation of innovation ability is weak and ineffective.Therefore,in the context of professional certification of engineering education,it is necessary to make reform of traditional education mode and improve the carrier support and target acquisition taking the Outcomes-based Education(OBE)as guide,the innovation ability cultivation as objective,to provide effective guarantee for cultivation of the top-notch talents.These have become issues that should not be ignored in the development of the Discipline of Food Science and Engineering. 展开更多
关键词 Food Science and Engineering Innovation ability Outcomes-based Education(OBE) Learning mode Teaching evaluation
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How is the biological information arranged in genome?
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作者 Masaharu Takeda 《American Journal of Molecular Biology》 2012年第3期171-186,共16页
The four nucleotides (bases), A. T. G and C were sophisticatedly arranged in the structural features in a single-strand of genomic DNA, 1) reverse-complement symmetry of base or base sequences, 2) bias of four bases, ... The four nucleotides (bases), A. T. G and C were sophisticatedly arranged in the structural features in a single-strand of genomic DNA, 1) reverse-complement symmetry of base or base sequences, 2) bias of four bases, 3) multiple fractality of the distribution of each four bases depending on the distance in double logarithmic plot (power spectrum) of L (the distance of a base to the next base) vs. P(L) (the probability of the base-distribution at L), regardless species, forms, genome-sizes and GC-contents. In small genomes such as viruses and plasmids, the multiple fractality might be occasionally hard to distinguish clearly with the power-low-tail region (multi-fractal dimension) because of the low base numbers. In this review article, the author showed that 1) the structural features for the biologically active genomic DNA were observed all living cells including the organelle- and the viralgenome, 2) the potentiality of a new analytical method of the genome structure based on the appearance frequency, Sequence Spectrum Method (SSM) could be analyzed DNA, RNA and protein on genome, 3) the structural features of genome might be related the biological complexity. These findings might be useful extremely to understand the living cells, and the entire genome as a “field” of biological information should need to analyze. 展开更多
关键词 Entire GENOME BIOLOGICAL INFORMATION Field LIVING CELLS
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New Ionic Liquids with Buffering and Chelating Abilities for Enzyme Engineering
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作者 Guangnan Ou Biyan He 《Advances in Bioscience and Biotechnology》 2019年第10期320-330,共11页
Ionic liquids (ILs) with buffering and chelating abilities were designed and synthesized on the basis of ethylenediaminetetraacetic acid (EDTA) for the development of buffered enzymatic IL systems and for enzymatic re... Ionic liquids (ILs) with buffering and chelating abilities were designed and synthesized on the basis of ethylenediaminetetraacetic acid (EDTA) for the development of buffered enzymatic IL systems and for enzymatic reaction in heavy metal containing aqueous system. Transesterification activity of Candida antarctica lipase B dissolved in the hydroxyl-functionalized IL was buffer dependent. High activity and outstanding stability was obtained with the buffered enzymatic IL systems for the transesterification. In heavy metal containing aqueous system, EDTA IL buffers as Hg2+ chelators protected horseradish peroxidase (HRP) against Hg2+-induced denaturation and precipitation. Higher pH favored the protection, while at lower pH the protection diminished. We can conclude that the new ILs possess both buffering and chelating abilities. 展开更多
关键词 Ionic Liquid EDTA Buffer CHELATOR LIPASE Peroxidise Heavy Metal
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Construction of Escherichia coli by Metabolic Engineering for Synthesis of Mesaconic Acid
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作者 Bangxu WANG Xingtao ZHAO Jie CHENG 《Agricultural Biotechnology》 CAS 2023年第1期4-7,共4页
Mesaconic acid has a special chemical structure and can undergo a series of reactions such as polymerization and addition. It is an important chemical intermediate and widely used in material, chemical and other indus... Mesaconic acid has a special chemical structure and can undergo a series of reactions such as polymerization and addition. It is an important chemical intermediate and widely used in material, chemical and other industries. The chemical synthesis of mesaconic acid requires nitric acid, which is dangerous and harmful to the environment. The production of mesaconic acid by microbial fermentation has the characteristics of low raw material price, high efficiency and strong specificity, and thus a strong industrial application prospect. Mesaconic acid is an intermediate product of glutamic acid degradation pathway of microorganisms such as Clostridium tetani. However, at present, few reports have been conducted on the production of mesaconic acid by metabolic engineering microorganisms. In this study, glutamate mutase(GLM) and 3-methylaspartate ammonialyase(MAL) from C. tetani were recombined and expressed in Escherichia coli, and the obtained strain, BL21(DE3)/pETDuet-1-MAL-mutS-mutE, achieved the yield of mesaconic acid of 1.06 g/L. Compared with the wild type, the yields of mesaconic acid from mutants G133A and G133S increased by 21% and 16%, respectively. After 24 h of flask fermentation, the yields of mesaconic acid reached 1.28 and 1.23 g/L, respectively. This study can provide reference for microbial synthesis of mesaconic acid. 展开更多
关键词 Mesaconic acid Glutamate mutase Escherichia coli Metabolic engineering
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Evaluation of the Microbiological Quality of Different Moroccan Drinking Water in the Beni Mellal Region
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作者 Rachid Hnini Said Ihbour +4 位作者 Lhou Ouhida Hasna Merzouki Ahmed Ait Chaoui Fatiha Chigr Mohamed Najimi 《Journal of Geoscience and Environment Protection》 2019年第5期105-115,共11页
Drinking water is water that does not contain pathogens or chemicals at levels that may be harmful to health. Beni Mellal region, one of the major rich areas in ground and surface water in Morocco (the rivers like Oum... Drinking water is water that does not contain pathogens or chemicals at levels that may be harmful to health. Beni Mellal region, one of the major rich areas in ground and surface water in Morocco (the rivers like Oum Errabia, Darna, ...;Bin el-Ouidane and martyr Ahmed El Hansali dams and sources like Ain Asserdoune, …) is located in the North-Centre of Morocco. The main objective of the present study was to evaluate the microbiological quality of different drinking waters originated from sources, faucets, fountains and wells in the Beni Mellal city and its agricultural surrounding areas. For this, hygienic quality indicator parameters of water quality were determined by assessing the analysis of Total Coliforms Count, Fecal Coliforms Count, streptococcus D and revivable germs while germs such as Anaerobic Sulphite-reducing Bacteria, S. aureus and Salmonella sp, were carried out according to national and international standards. The analysis of the microbiological results found for all the different samples waters investigated in this study revealed that the waters originated from fountains, faucets and sources were proper for main consumption at microbiological point of view while the wells waters were improper for consumption according to norms. Finally, it appears, from the results obtained, that the potential risk of infection of water consumers especially (groundwater) calls for prompt intervention in order to alleviate the potential health impact of water-borne diseases in the community. From this, a proper sanitary survey and implementation of water and sanitation projects in the community is recommended. 展开更多
关键词 Water QUALITY MICROBIOLOGICAL Analysis STANDARDS Beni Mellal Morocco
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Identification and Biological Activities of the Phenolic Compounds in <i>Eisenia arborea</i>
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作者 Hyeon Cheol Shin Ignacio Beamonte Wayas +1 位作者 Byoung Wook Choi Bong Ho Lee 《American Journal of Plant Sciences》 2021年第2期259-265,共7页
Four polyphenols were isolated and purified from a brown alga </span><i><span style="font-family:Verdana;">Eisenia arborea</span></i><span style="font-family:Verdana;&qu... Four polyphenols were isolated and purified from a brown alga </span><i><span style="font-family:Verdana;">Eisenia arborea</span></i><span style="font-family:Verdana;">. These phlorotannin compounds showed strong radical scavenging and some enzyme inhibitory activities. All of the compounds showed strong antioxidative, acetylcholinesterase and butyrylcholinesterase inhibitory, and tyrosinase inhbibitory activities at 100 μg/mL. Dieckol and PFF inhibited butyrylcholinesterase, a new target for the treatment of Alzheimer’s disease, very strongly even at 10 μg/mL</span></span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> more strongly than AChE. These two compounds also effectively inhibited tyrosinase. These results support the potential of developing natural antioxidants and antidementia agents from the brown alga. 展开更多
关键词 Eisenia arborea Phenolic Compounds DPPH Radical Scavenger Enzyme Inhibition ISOLATION
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