Lactic acid was discovered in 1780 by C.W. Scheele in sour milk, and in 1881 Fermi obtained lactic acid by fermentation, resulting in its industrial production. The yearly world lactic acid ...production is expected to reach 259,000 metric tons by the year 2012. The interest in lactic acid is related to many aspects, among which is its relatively high added-value. In addition, such a chemical is GRAS (Generally Recognized As Safe), being recognized as harmless by the United States Food and Drug Administration, has a market with great growth potential, can be alternatively produced by fermentation or chemical synthesis and can employ a large variety of different waste materials as substrates. Lactic acid has many applications. Its existence in the form of two stereoisomers does in fact make the application of one of them or of the racemic mixture of great concern in different fields. In particular, the food and pharmaceutical industries have a preference for the isomer l(+), the only one that can be metabolized by the human body; however, the chemical industry requires one of the pure isomers or a mixture of both, according to the application. This review describes biotechnological processes to obtain lactic acid from polymeric substrates such as starchy and lignocellulosic materials. Open challenges are related to the technological optimization of the fermentation process and product purification and recovery. In addition, the opportunities and difficulties associated with using raw materials for lactic acid production are discussed.
► Lactic acid has many applications in the food and pharmaceutical industries. ► Description of biotechnological processes involving fermentation by fungi and bacteria. ► Starchy and lignocellulosic materials are used for obtaining lactic acid. ► Challenges related to the technological optimization of the fermentation process.
Hydrogen peroxide (H2O2) has a wide range of important applications in various fields including chemical industry, environmental remediation, and sustainable energy conversion/storage. Nevertheless, ...the stark disconnect between today's huge market demand and the historical unsustainability of the currently-used industrial anthraquinone-based production process is promoting extensive research on the development of efficient, energy-saving and sustainable methods for H2O2 production. Among several sustainable strategies, H2O2 production via electrochemical and photochemical routes has shown particular appeal, because only water, O2, and solar energy/electricity are involved during the whole process. In the past few years, considerable efforts have been devoted to the development of advanced electrocatalysts and photocatalysts for efficient and scalable H2O2 production with high efficiency and stability. In this review, we compare and contrast the two distinct yet inherently closely linked catalytic processes, before we detail recent advances in the design, preparation, and applications of different H2O2 catalyst systems from the viewpoint of electrochemical and photochemical approaches. We close with a balanced perspective on remaining future scientific and technical challenges and opportunities.
Soil fumigation with Vapam Zuzak, Krista A; Strelkov, Stephen E; Turnbull, George D ...
Canadian journal of plant science,
02/2023, Volume:
103, Issue:
1
Journal Article
Peer reviewed
Clubroot, a damaging disease of canola (Brassica napus L.) caused by the soilborne parasite Plasmodiophora brassicae Woronin, is spreading across Alberta and other provinces of western Canada. The ...movement of infested soil on field machinery is the main mechanism of dispersal, with clubroot generally occurring first as localized patches near field entrances. In this study, the soil fumigant Vapam (metam sodium) was evaluated as a management option for foci of P. brassicae infestation. Replicated experiments at two field sites in central Alberta showed reductions in clubroot severity ranging from 9% to 51% following treatment with varying rates of Vapam. Decreases in clubroot severity of up to 28% were observed in the year following Vapam treatment, indicating some potential residual effects and (or) a reduction in the amount of inoculum returned to the soil in the previous year. While Vapam shows some promise as a clubroot management tool, an integrated approach will be required for the sustainable management of this disease on canola.
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-Dimethylformamide (DMF) is frequently used as an aprotic solvent in chemical transformations in laboratories of academia as well as in those of chemical industry. In the present review, we ...will reveal that DMF is actually something much more than a solvent. It is a unique chemical since, as well as being an effective polar aprotic solvent, it can play three other important roles in organic chemistry. It can be used as a reagent, a catalyst, and a stabilizer.
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-Dimethylformamide (DMF) is frequently used as an aprotic solvent in chemical transformations. It is a multipurpose compound besides being an effective polar aprotic solvent. DMF can be act as a reagent, a catalyst and a stabilizer.
Cyclic peptides have been attracting a lot of attention in recent decades, especially in the area of drug discovery, as more and more naturally occurring cyclic peptides with diverse biological ...activities have been discovered. Chemical synthesis of cyclic peptides is essential when studying their structure–activity relationships. Conventional peptide cyclization methods via direct coupling have inherent limitations, like the susceptibility to epimerization at the C-terminus, poor solubility of fully protected peptide precursors, and low yield caused by oligomerization. In this regard, chemoselective ligation-mediated cyclization methods have emerged as effective strategies for cyclic peptide synthesis. The toolbox for cyclic peptide synthesis has been expanded substantially in the past two decades, allowing more efficient synthesis of cyclic peptides with various scaffolds and modifications. This Review will explore different chemoselective ligation technologies used for cyclic peptide synthesis that generate both native and unnatural peptide linkages. The practical issues and limitations of different methods will be discussed. The advance in cyclic peptide synthesis will benefit the biological and medicinal study of cyclic peptides, an important class of macrocycles with potentials in numerous fields, notably in therapeutics.
Industrialization of Biology National Research Council; Division on Earth and Life Studies; Board on Life Sciences ...
03/2015
eBook
Open access
The tremendous progress in biology over the last half century - from Watson and Crick's elucidation of the structure of DNA to today's astonishing, rapid progress in the field of synthetic biology - ...has positioned us for significant innovation in chemical production. New bio-based chemicals, improved public health through improved drugs and diagnostics, and biofuels that reduce our dependency on oil are all results of research and innovation in the biological sciences. In the past decade, we have witnessed major advances made possible by biotechnology in areas such as rapid, low-cost DNA sequencing, metabolic engineering, and high-throughput screening. The manufacturing of chemicals using biological synthesis and engineering could expand even faster. A proactive strategy - implemented through the development of a technical roadmap similar to those that enabled sustained growth in the semiconductor industry and our explorations of space - is needed if we are to realize the widespread benefits of accelerating the industrialization of biology.
Industrialization of Biology presents such a roadmap to achieve key technical milestones for chemical manufacturing through biological routes. This report examines the technical, economic, and societal factors that limit the adoption of bioprocessing in the chemical industry today and which, if surmounted, would markedly accelerate the advanced manufacturing of chemicals via industrial biotechnology. Working at the interface of synthetic chemistry, metabolic engineering, molecular biology, and synthetic biology, Industrialization of Biology identifies key technical goals for next-generation chemical manufacturing, then identifies the gaps in knowledge, tools, techniques, and systems required to meet those goals, and targets and timelines for achieving them. This report also considers the skills necessary to accomplish the roadmap goals, and what training opportunities are required to produce the cadre of skilled scientists and engineers needed.
Modular chemical process intensification can dramatically improve energy and process efficiencies of chemical processes through enhanced mass and heat transfer, application of external force fields, ...enhanced driving forces, and combinations of different unit operations, such as reaction and separation, in single-process equipment. These dramatic improvements lead to several benefits such as compactness or small footprint, energy and cost savings, enhanced safety, less waste production, and higher product quality. Because of these benefits, process intensification can play a major role in industrial and manufacturing sectors, including chemical, pulp and paper, energy, critical materials, and water treatment, among others. This article provides an overview of process intensification, including definitions, principles, tools, and possible applications, with the objective to contribute to the future development and potential applications of modular chemical process intensification in industrial and manufacturing sectors. Drivers and barriers contributing to the advancement of process intensification technologies are discussed.
A one-pot system for the conversion of methyl propanoate (MeP) to methyl methacrylate (MMA) has been investigated. In particular, this study is focused on the possibility of performing catalytic ...dehydrogenation of methanol for the insitu production of anhydrous formaldehyde, which is then consumed in a one-pot base-catalysed condensation with MeP to afford methyl 3-hydroxy-2-methylpropanoate, which spontaneously dehydrogenates to MMA, some of which is subsequently hydrogenated to methyl 2-methypropanoate (MiBu).
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