Muconic acid is a six-carbon dicarboxylic acid with conjugated double bonds that finds extensive use in the food (additive), chemical (production of adipic acid, monomer for functional resins and bio-plastics), and pharmaceutical sectors. The biosynthesis of muconic acid has been the subject of recent industrial and scientific attention. However, because of its low concentration in aqueous solutions and high purity requirement, downstream separation presents a significant problem.
View Article and Find Full Text PDFFolic acid (vitamin B9) is an essential micronutrient for human health. It can be obtained using different biological pathways as a competitive option for chemical synthesis, but the price of its separation is the key obstacle preventing the implementation of biological methods on a broad scale. Published studies have confirmed that ionic liquids can be used to separate organic compounds.
View Article and Find Full Text PDFIonic liquids (ILs) are considered a green viable organic solvent substitute for use in the extraction and purification of biosynthetic products (derived from biomass-solid/liquid extraction, or obtained through fermentation-liquid/liquid extraction). In this review, we analyzed the ionic liquids (greener alternative for volatile organic media in chemical separation processes) as solvents for extraction (physical and reactive) and pertraction (extraction and transport through liquid membranes) in the downstream part of organic acids production, focusing on current advances and future trends of ILs in the fields of promoting environmentally friendly products separation.
View Article and Find Full Text PDFFumaric, malic, and succinic acids have been selectively separated from their mixture obtained by Rhizopus oryzae fermentation using reactive extraction with Amberlite LA-2 dissolved in three solvents with different dielectric constants (n-heptane, n-butyl acetate, and dichloromethane). This technique allows recovering preferentially fumaric acid from the mixture, the raffinate containing only malic and succinic acids. The extractant concentration and organic phase polarity control the efficiency and selectivity of acids extraction.
View Article and Find Full Text PDFExperimental studies on the reactive extraction of fumaric acid with Amberlite LA-2 from suspensions using three solvents with different dielectric constants varying from 9.08 to 1.90 (dichloromethane, n-butyl acetate, and n-heptane, respectively) underlined the particular behavior of the extraction system in the presence of fungal biomass.
View Article and Find Full Text PDFCitizen science is a growing field of research and practice, generating new knowledge and understanding through the collaboration of citizens in scientific research. As the field expands, it is becoming increasingly important to consider its potential to foster education and learning opportunities. Although progress has been made to support learning in citizen science projects, as well as to facilitate citizen science in formal and informal learning environments, challenges still arise.
View Article and Find Full Text PDFRobotic-assisted surgery (RAS) involves training processes and challenges that differ from open or laparoscopic surgery, particularly regarding the possibilities of observation and embodied guidance. The video recording and the dual-console system creates a potential opportunity for participation. Our research, conducted within the department of visceral surgery of a big Swiss, public, academic hospital, uses a methodology based on the co-analysis of video recordings with surgeons in self-confrontation interviews, to investigate the teaching activity of the lead surgeon supervising a surgeon in training at the dual console.
View Article and Find Full Text PDFBringing together perspectives is rarely an easy task. By assembling researchers from cognitive and cultural traditions to discuss their reciprocal research in the field of psychology of religion, we thought that we will end up with an ecumenical conclusion, everyone being convinced that the other perspective will enrich her or his approach in the future. In this introduction, our objective is to show that it was not exactly the case and, by writing a two-voices introduction, to understand why we were eventually not so sure that we were all studying the same object.
View Article and Find Full Text PDFFumaric acid is a valuable compound used in foods, beverages, detergents, animal feed, pharmaceuticals and miscellaneous industrial products. It is produced on a large scale by the petrochemical route but the current tendency is towards implementing "green production" and environmental friendly technologies like biotechnological production of fumaric acid using low-cost raw materials. In this context, numerous studies focus on improving the fermentation process not only by using renewable raw material and genetically modified microorganisms, but also by developing and applying different downstream techniques for easy recovery of fumaric acid from the fermented broth.
View Article and Find Full Text PDFFront Psychiatry
April 2018
In April 2016, Armin, an asylum seeker in a village of Switzerland, set himself alight in the public square of the town, one of a few cases reported across Europe. He performed the act following a denied request for asylum and was saved by bystanders. We present the results of two qualitative interviews conducted with Armin, his translator and his roommate following the incident.
View Article and Find Full Text PDFBackground: This paper reports on two case studies conducted by the Activity Clinic team to support the prevention of Work-Related Musculoskeletal Disorders (WRMSDs) in the workplace. Research so far qualifies WRMSDs as multifactorial and organizational pathologies. It has also demonstrated that in situ clinical analysis of the work activity improves the understanding of WRMSDs and their long-term prevention.
View Article and Find Full Text PDFRev Med Chir Soc Med Nat Iasi
June 2014
Amino acids can be obtained by biosynthesis, by protein hydrolysis or by extraction from natural sources. The most efficient methods are the first two, but the separation of amino acids from fermentation broths or protein hydrolysates is rather difficult. Amino acids dissociate in aqueous solutions, forming characteristic ionic species depending on the solution pH-value.
View Article and Find Full Text PDFThis paper is dedicated to the study on external and internal mass transfers of glucose for succinic fermentation under substrate and product inhibitions using a bioreactor with a stationary basket bed of immobilized Actinobacillus succinogenes cells. By means of the substrate mass balance for a single particle of biocatalysts, considering the Jerusalimsky kinetic model including both inhibitory effects, specific mathematical expressions have been developed for describing the profiles of the substrate concentrations and mass flows in the outer and inner regions of biocatalyst particles, as well as for estimating the influence of internal diffusion on glucose consumption rate. The results indicated that very low values of internal mass flow could be reached in the particles center.
View Article and Find Full Text PDFThis paper is dedicated to the study on the external and internal mass transfers of glucose for succinic acid fermentation under substrate and product inhibitions using a bioreactor with stirred bed of immobilized Actinobacillus succinogenes cells. By means of the substrate mass balance for a single particle of biocatalysts, considering the kinetic model adapted for both inhibitory effects, specific mathematical models were developed for describing the profiles of the substrate concentration in the outer and inner regions of biocatalysts and for estimating the substrate mass flows in the liquid boundary layer surrounding the particle and inside the particle. The values of the mass flows were significantly influenced by the internal diffusion velocity and rate of the biochemical reaction of substrate consumption.
View Article and Find Full Text PDFRev Med Chir Soc Med Nat Iasi
July 2011
Unlabelled: This work investigates the production of succinic acid by immobilized A. succinogenes cells, using a bioreactor with stirred/mobile bed of biocatalysts.
Material And Method: The experiments have been carried out for different sizes of biocatalysts particle, under substrate and product inhibitory effects.
The studies on facilitated pertraction of PABA with Amberlite LA-2 and 1-octanol as phase modifier indicated the increase of the process efficiency and, implicitly, of the transport capacity of the liquid membrane by adding KOH in the stripping phase. Thus, the use of KOH led to the diminution of the kinetic resistance of the reextraction process, with positive effects on the acid final mass flow and permeability factor. Compared to the similar pertraction systems containing NaOH in the stripping phase and in direct correlation with the pertraction parameters (pH-gradient between the feed and stripping phases, carrier and alchohol concentrations inside the liquid membrane), the final mass flow can be accelerated for about 1.
View Article and Find Full Text PDFNeurogastroenterol Motil
May 2010
Background: The wireless motility capsule (WMC) measures intraluminal pH and pressure, and records transit time and contractile activity throughout the gastrointestinal tract. Our hypothesis is that WMC can differentiate antroduodenal pressure profiles between healthy people and patients with upper gut motility dysfunctions. This study aims to analyze differences in the phasic pressure profiles of the stomach and small intestine in healthy and gastroparetic subjects.
View Article and Find Full Text PDFGua Sha is a traditional Chinese folk therapy that employs skin scraping to cause subcutaneous microvascular blood extravasation and bruises. The protocol for bioluminescent optical imaging of HO-1-luciferase transgenic mice reported in this manuscript provides a rapid in vivo assay of the upregulation of the heme oxygenase-1 (HO-1) gene expression in response to the Gua Sha procedure. HO-1 has long been known to provide cytoprotection against oxidative stress.
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