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1.
Use of sustainable chemistry to produce an acyl amino acid surfactant   总被引:1,自引:0,他引:1  
Surfactants find wide commercial use as foaming agents, emulsifiers, and dispersants. Currently, surfactants are produced from petroleum, or from seed oils such as palm or coconut oil. Due to concerns with CO2 emissions and the need to protect rainforests, there is a growing necessity to manufacture these chemicals using sustainable resources In this report, we describe the engineering of a native nonribosomal peptide synthetase pathway (i.e., surfactin synthetase), to generate a Bacillus strain that synthesizes a highly water-soluble acyl amino acid surfactant, rather than the water insoluble lipopeptide surfactin. This novel product has a lower CMC and higher water solubility than myristoyl glutamate, a commercial surfactant. This surfactant is produced by fermentation of cellulosic carbohydrate as feedstock. This method of surfactant production provides an approach to sustainable manufacturing of new surfactants.  相似文献   

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Eco‐industrial networks (EINs, of which eco‐industrial parks are a subset) have gained support as a solution that simultaneously reduces environmental burdens and promotes economic interests. EINs operate under a mutualistic framework, where waste materials and energy are exchanged between industries to their mutual benefit, creating a diverse web of flows. Recent studies have focused on analogies between food webs (FWs) and EINs, measuring a network's success at ecological imitation as representative of its sustainability. Studies have focused heavily on the number of links and nodes in a network, but have neglected the economic reality that each investment comes at the opportunity cost of all alternatives. This analysis focuses on the nestedness metric as used by ecologists to address this pivotal facet to the FW‐EIN analogy. Nestedness describes an ecological strategy for the position of links between nodes in a network in a way that maximizes network cycling for a given number of connections. This metric presents many advantages for EIN design and analysis, including maturity independence, size normalization, and a strong statistical record in highly mutualistic ecological systems. Application of nestedness to EINs indicates a lower presence of nested structures and more randomness than what is typically seen in FWs. The industrial networks also display a correlation between high nestedness and internal cycles, suggesting that the reuse of materials and energy in EINs can be improved upon by increasing the nestedness of structures.  相似文献   

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Organic chemistry has been, and for the foreseeable future will remain, vitally important for crop protection. Control of fungal pathogens, insect pests and weeds is crucial to enhanced food provision. As world population continues to grow, it is timely to assess the current situation, anticipate future challenges and consider how new chemistry may help meet those challenges. In future, agriculture will increasingly be expected to provide not only food and feed, but also crops for conversion into renewable fuels and chemical feedstocks. This will further increase the demand for higher crop yields per unit area, requiring chemicals used in crop production to be even more sophisticated. In order to contribute to programmes of integrated crop management, there is a requirement for chemicals to display high specificity, demonstrate benign environmental and toxicological profiles, and be biodegradable. It will also be necessary to improve production of those chemicals, because waste generated by the production process mitigates the overall benefit. Three aspects are considered in this review: advances in the discovery process for new molecules for sustainable crop protection, including tests for environmental and toxicological properties as well as biological activity; advances in synthetic chemistry that may offer efficient and environmentally benign manufacturing processes for modern crop protection chemicals; and issues related to energy use and production through agriculture.  相似文献   

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工业酶研究中的计算化学方法   总被引:1,自引:0,他引:1  
刘海燕 《生物工程学报》2019,35(10):1819-1828
文中介绍用于工业酶研究特别是用于指导酶工程的主要计算化学方法,包括分子力学力场和分子动力学模拟、量子力学以及量子力学/分子力学结合模型、连续介质静电模型以及分子对接等。文中从以下两个角度分别概要地介绍这些方法:一是方法本身的基本概念、原始计算结果、适用条件和优缺点等;二是通过计算得到有价值的信息,指导突变体和突变库设计。  相似文献   

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First, fundamental properties (structure, acid and redox properties) and advantages of solid polyoxometalate catalysts (catalyst design by acid and redox control, molecularity, unusual reaction field and unique basicity) are explained. Then, the mechanism of alcohol dehydration elucidated by direct observation of reaction intermediates by solid-state NMR and the very high activity of Cs2.5H0.5PW12O40 are described. Finally several industrial applications of polyoxometalate catalysts are briefly introduced placing stress on the role of unique chemical properties of polyoxometalates.  相似文献   

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刘晶茹  刘瑞权  姚亮 《生态学报》2012,32(20):6553-6557
生产和消费是产生诸多环境问题的根本原因,而可持续生产和消费则是实现可持续发展的根本途径。基于产业生态学视角,界定了可持续消费的定义及内涵,认为可持续消费首先须符合代内公平、代际公平和资源能源永续合理利用等可持续理念;其次辨识了可持续消费研究依次经历关注消费者行为直接环境影响、关注产品和服务生命周期环境影响到关注消费者责任3个阶段;最后结合我国城市化、工业化背景,提出我国可持续消费研究应该以城市居民为重点、加强生命周期数据库建设和内注重可持续生产等建议。  相似文献   

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Seawater desalination has significantly developed towards membrane technology than phase change process during last decade. Seawater reverse osmosis (SWRO) in general is the most familiar process due to higher water recovery and lower energy consumption compared to other available desalination processes. Despite major advancements in SWRO technology, desalination industry is still facing significant amount of practical issues. Therefore, the potentials and problems faced by current SWRO industries and essential study areas are discussed in this review for the benefit of desalination industry. It is important to consider all the following five components in SWRO process i.e. (1) intake (2) pre-treatment (3) high pressure pumping (4) membrane separation (performance of membranes and brine disposal) and (5) product quality. Development of higher corrosion resistant piping materials or coating materials, valves, and pumps is believed to be in higher research demand. Furthermore, brine management, that includes brine disposal and resource recovery need further attention. Pre-treatment sludge management and reduced cleaning in place flush volume will reduce the capital costs associated with evaporation ponds and the maintenance costs associated with disposal and transportation reducing the unit cost of water.  相似文献   

9.
Coupons of fourteen different stainless steels were investigated in terms of surface chemistry and ease of cleaning. Steel surfaces were exposed to Bacillus cereus spores in static saline solution for 2 h. Surfaces were rinsed and then covered with whole milk and allowed to dry. Surfaces were then cleaned in an experimental flow system that mimics an industrial application. After cleaning, remaining spores were released by sonication, spores cultured and colony forming units determined. Surfaces with higher levels of Fe in the outer surface of the passive film cleaned more easily. There was a relation between the polar component and ease of cleaning. The higher the polar component the more easily the surface cleaned. The cleaning mechanism involves dissolution of Fe enriched hydroxide films on the surface.  相似文献   

10.
Filamentous actinomycetes are commercially widely used as producers of natural products (in particular antibiotics) and of industrial enzymes. However, the mycelial lifestyle of actinomycetes, resulting in highly viscous broths and unfavorable pellet formation, has been a major bottleneck in their commercialization. Here we describe the successful morphological engineering of industrially important streptomycetes through controlled expression of the morphogene ssgA. This led to improved growth of many industrial and reference streptomycetes, with fragmentation of the mycelial clumps resulting in significantly enhanced growth rates in batch fermentations of Streptomyces coelicolor and Streptomyces lividans. Product formation was also stimulated, with a twofold increase in yield of enzyme production by S. lividans. We anticipate that the use of the presented methodology will make actinomycetes significantly more attractive as industrial and sustainable production hosts.  相似文献   

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In this study, a model synthetic azo dye (Basic red 46) bioremoval by Carpinus betulus sawdust as inexpensive, eco-friendly, and sustainable biosorbent from aqueous solution was examined in a batch biosorption system. The effective environmental parameters on the biosorption process, such as the value of pH, amount of biosorbent, initial dye concentration and contact time were optimized using classical test design. The possible dye-biosorbent interaction was determined by Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). The equilibrium, thermodynamic, and kinetic studies for the biosorption of Basic red 46 onto the sawdust biomass were performed. In addition, a single-stage batch dye biosorption system was also designed. The dye biosorption yield of biosorbent was significantly influenced by the change of operating variables. The experimental data were best described by the Freundlich isotherm model and both the pseudo-first-order kinetic and the pseudo-second-order kinetic models. Thermodynamic research indicated that the biosorption of dye was feasible and spontaneous. Based on the Langmuir isotherm model, the biosorbent was found to have a maximum biosorption potential higher than many other biosorbents in the literature (264.915?mg g?1). Thus, this investigation presents a novel green option for the assessment of waste sawdust biomass as a cheap and effective biosorbent material.  相似文献   

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In order to decrease carbon emissions and negative environmental impacts of various pollutants, more bulk and/or fine chemicals are produced by bioprocesses, replacing the traditional energy and fossil based intensive route. The Gram-negative rod-shaped bacterium, Escherichia coli has been studied extensively on a fundamental and applied level and has become a predominant host microorganism for industrial applications. Furthermore, metabolic engineering of E. coli for the enhanced biochemical production has been significantly promoted by the integrated use of recent developments in systems biology, synthetic biology and evolutionary engineering. In this review, we focus on recent efforts devoted to the use of genetically engineered E. coli as a sustainable platform for the production of industrially important biochemicals such as biofuels, organic acids, amino acids, sugar alcohols and biopolymers. In addition, representative secondary metabolites produced by E. coli will be systematically discussed and the successful strategies for strain improvements will be highlighted. Moreover, this review presents guidelines for future developments in the bio-based chemical production using E. coli as an industrial platform.  相似文献   

14.
Summary Northern Australia's globally significant savannas and rivers face major threats, from cattle to weeds to land clearing to climate change. In the face of imperatives and pressures such as reducing carbon emissions, nature conservation, alleviating Indigenous disadvantage, the resources boom and global food security, how should development be managed to protect its globally significant ecosystems? Nine planks in a ‘Sustainable Northern Australia’ agenda are proposed: (i) enhance investment in mitigating pervasive landscape threats; (ii) strengthen support for Indigenous Caring for Country activities and incorporation of Traditional Ecological Knowledge into land management; (iii) align and strengthen invasive species control and management; (iv) facilitate new economic development pathways focused on sustainability; (v) build climate resilience by maintaining and enhancing landscape‐scale connectivity; (vi) protect free‐flowing rivers from dams and major water resource development; (vii) establish and effectively manage a large interconnected network of protected areas; (viii) develop cooperative governance arrangements; and (ix) enhance knowledge generation and research and monitoring capacity.  相似文献   

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Reducing food waste is essential if we want to create a more sustainable food system, which is why halving per capita food waste by 2030 has been included in the UN Sustainable Development Goals. The main aim of this paper is to demonstrate that by using digital tools to monitor food provisioning and management within canteens, it is possible to achieve a more sustainable food service management within industrial companies and to reduce the overall quantity and environmental impacts of food preparation and consumption thus achieving economic benefits. Longitudinal 2018 and 2019 data collected from the canteen of a major Italian food production company were analyzed. The results showed that the amount of food lost and wasted has decreased over time, reaping important environmental benefits and illustrating specific differences between the food lost in meal preparation and the food left on employees’ plates. It is therefore important to implement education initiatives and to use digital tools to share food-related data collected within companies among both employees and kitchen and catering staff in order to raise awareness of their behavioral strengths and weaknesses. From this perspective, new interventions at both kitchen and customer/worker levels are introduced and discussed.  相似文献   

17.
Oilseeds provide a unique platform for the production of high-value fatty acids that can replace non-sustainable petroleum and oceanic sources of specialty chemicals and aquaculture feed. However, recent efforts to engineer the seeds of crop and model plant species to produce new types of fatty acids, including hydroxy and conjugated fatty acids for industrial uses and long-chain omega-3 polyunsaturated fatty acids for farmed fish feed, have met with only modest success. The collective results from these studies point to metabolic 'bottlenecks' in the engineered plant seeds that substantially limit the efficient or selective flux of unusual fatty acids between different substrate pools and ultimately into storage triacylglycerol. Evidence is emerging that diacylglycerol acyltransferase 2, which catalyzes the final step in triacylglycerol assembly, is an important contributor to the synthesis of unusual fatty acid-containing oils, and is likely to be a key target for future oilseed metabolic engineering efforts.  相似文献   

18.
Enzyme-catalyzed polymerization and degradation will play an important role in both the synthesis and chemical recycling of green and sustainable polyurethane. This minireview covers the new synthetic routes to polyurethane without using diisocyanate, the biodegradation of polyurethane, and the enzymatic synthesis and the chemical recycling of poly(ester-urethane) (PEU) and poly(carbonate-urethane) (PCU). The lipase-catalyzed polymerization of low molecular weight and biodegradable urethanediols with short-chain dialkyl carbonate and alkanedioates produced PCU and PEU, respectively. They were readily degraded in an organic solvent into the repolymerizable cyclic oligomers by lipase as a novel chemical recycling. These results will be applicable for the production strategies of green and sustainable polyurethanes.  相似文献   

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