Summary
Lipid recovery and purification from microalgal cells continues to be a significant bottleneck in biodiesel production due to high costs involved and a high energy demand. Therefore, there is ...a considerable necessity to develop an extraction method which meets the essential requirements of being safe, cost‐effective, robust, efficient, selective, environmentally friendly, feasible for large‐scale production and free of product contamination. The use of wet concentrated algal biomass as a feedstock for oil extraction is especially desirable as it would avoid the requirement for further concentration and/or drying. This would save considerable costs and circumvent at least two lengthy processes during algae‐based oil production. This article provides an overview on recent progress that has been made on the extraction of lipids from wet algal biomass. The biggest contributing factors appear to be the composition of algal cell walls, pre‐treatments of biomass and the use of solvents (e.g. a solvent mixture or solvent‐free lipid extraction). We compare recently developed wet extraction processes for oleaginous microalgae and make recommendations towards future research to improve lipid extraction from wet algal biomass.
Lipid recovery and purification from microalgal cells is a significant bottleneck in microalgal oil production due to high costs involved and a high energy demand. The use of wet concentrated algal biomass as a feedstock for oil extraction is desirable as it avoids further concentration and/or drying. This article provides an overview on recent progress on lipid extraction from wet algal biomass and makes recommendations towards further improvements.
Engineered mutualistic consortia of microalgae and bacteria may be a means of assembling a novel combination of metabolic capabilities with potential biotechnological advantages. Microalgae are ...promising organisms for the sustainable production of metabolites of commercial interest, such as lipids, carbohydrates, pigments, and proteins. Several studies reveal that microalgae growth and cellular storage of these metabolites can be enhanced significantly by co-cultivation with growth-promoting bacteria. This review summarizes the state of the art of microalgae-bacteria consortia for the production of microalgal metabolites. We discuss the current knowledge on microalgae-bacteria mutualism and the mechanisms of bacteria to enhance microalgae metabolism. Furthermore, the potential routes for a microalgae-bacteria biorefinery are outlined in an attempt to overcome the economic failures and negative energy balances of the existing production processes.
Soil restoration is one of the biggest challenges of this century. Besides the negative impacts of climate change, the current increase in food demands has put severe pressure on soil resources, ...resulting in a significant area of degraded land worldwide. However, beneficial microorganisms, such as microalgae and plant growth-promoting bacteria, have an outstanding ability to restore soil health and fertility. In this mini-review, we summarize state-of-the-art knowledge on these microorganisms as amendments that are used to restore degraded and contaminated soils. Furthermore, the potential of microbial consortia to maximize beneficial effects on soil health and boost the production of plant-growth-promoting compounds within a mutualistic interaction is discussed.
Transport and Golgi Organization protein 2 Homolog (TANGO2)-related disease is an autosomal recessive disorder caused by mutations in the TANGO2 gene. Symptoms typically manifest in early childhood ...and include developmental delay, stress-induced episodic rhabdomyolysis, and cardiac arrhythmias, along with severe metabolic crises including hypoglycemia, lactic acidosis, and hyperammonemia. Severity varies among and within families. Previous studies have reported contradictory evidence of mitochondrial dysfunction. Since the clinical symptoms and metabolic abnormalities are suggestive of a broad dysfunction of mitochondrial energy metabolism, we undertook a broad examination of mitochondrial bioenergetics in TANGO2 deficient patients utilizing skin fibroblasts derived from three patients exhibiting TANGO2-related disease. Functional studies revealed that TANGO2 protein was present in mitochondrial extracts of control cells but not patient cells. Superoxide production was increased in patient cells, while oxygen consumption rate, particularly under stress, along with relative ATP levels and β-oxidation of oleate were reduced. Our findings suggest that mitochondrial function should be assessed and monitored in all patients with TANGO2 mutation as targeted treatment of the energy dysfunction could improve outcome in this condition.
TANGO2 deficiency disorder (TDD) is a neurodegenerative disease characterized by a broad and variable spectrum of clinical manifestations, even among individuals sharing the same pathogenic variants. ...Here, we report a severely affected individual with TDD presenting with intractable paroxysmal sympathetic hyperactivity (PSH). While progressive brain atrophy has been observed in TDD, PSH has not been reported. Despite comprehensive workup for an acute trigger, no definite cause was identified, and pharmacological interventions were ineffective to treat PSH. Ultimately care was redirected to comfort measures. This article expands the clinical phenotype of patients with TDD, highlights the possibility of PSH in these patients, and the need for continued research for better treatments of TDD.
Structural supercapacitors are multifunctional devices able to bear mechanical load while storing electrical energy. Carbon fibres can be used as a bifunctional component within structural ...supercapacitors, acting both as current collector and mechanical reinforcement. A promising route to such devices is to increase the surface area of carbon fibres, which can be achieved by the deposition of active materials, and embed them into a structural electrolyte. A highly sulfonated, high porosity hypercrosslinked polymer was deposited onto carbon fibres by electrophoretic deposition from an aqueous suspension. We investigated the effect of polymer and binder concentration in the deposition suspension on the electrochemical properties of the coated carbon fibre electrodes. Multifunctional structural composite supercapacitors had a fibre volume fraction of only 21% and possessed a tensile strength and Young's modulus of 495 MPa and 49 GPa, respectively. A specific capacitance of 1.2 F/g was reached, comparable to graphene coated carbon fibre electrodes. At room temperature and ambient humidity an energy density of 39 mWh/kg and a power density of 15 W/kg were measured. We demonstrate that moisture plays a major role in the energy storage mechanism in these SCs.
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•Sulfonated hypercrosslinked polymers (SHCPs) were synthesised.•SHCP particles were suspended in water and subsequently deposited on carbon fibres by electrophoretic deposition.•Structural composite supercapacitors were assembled with SHCP coated carbon fibres.•SHCP coated carbon fibre electrodes reached capacitance of up to 1.5 F/g in a structural electrolyte.
Nonketotic hyperglycinemia (NKH) is caused by deficient glycine cleavage enzyme activity and characterized by elevated brain glycine. Metabolism of glycine is connected enzymatically to serine ...through serine hydroxymethyltransferase and shares transporters with serine and threonine. We aimed to evaluate changes in serine and threonine in NKH patients, and relate this to clinical outcome severity. Age‐related reference values were developed for cerebrospinal fluid (CSF) serine and threonine from 274 controls, and in a cross‐sectional study compared to 61 genetically proven NKH patients, categorized according to outcome. CSF d‐serine and l‐serine levels were stereoselectively determined in seven NKH patients and compared to 29 age‐matched controls. In addition to elevated CSF glycine, NKH patients had significantly decreased levels of CSF serine and increased levels of CSF threonine, even after age‐adjustment. The CSF serine/threonine ratio discriminated between NKH patients and controls. The CSF glycine/serine aided in discrimination between severe and attenuated neonates with NKH. Over all ages, the CSF glycine, serine and threonine had moderate to fair correlation with outcome classes. After age‐adjustment, only the CSF glycine level provided good discrimination between outcome classes. In untreated patients, d‐serine was more reduced than l‐serine, with a decreased d/l‐serine ratio, indicating a specific impact on d‐serine metabolism. We conclude that in NKH the elevation of glycine is accompanied by changes in l‐serine, d‐serine and threonine, likely reflecting a perturbation of the serine shuttle and metabolism, and of one‐carbon metabolism. This provides additional guidance on diagnosis and prognosis, and opens new therapeutic avenues to be explored.
Background
Acute liver failure (ALF) in infancy and childhood is a life-threatening emergency and in about 50 % the etiology remains unknown. Recently biallelic mutations in
NBAS
were identified as a ...new molecular cause of ALF with onset in infancy, leading to recurrent acute liver failure (RALF).
Methods
The phenotype and medical history of 14 individuals with NBAS deficiency was studied in detail and functional studies were performed on patients’ fibroblasts.
Results
The phenotypic spectrum of NBAS deficiency ranges from isolated RALF to a multisystemic disease with short stature, skeletal dysplasia, immunological abnormalities, optic atrophy, and normal motor and cognitive development resembling SOPH syndrome. Liver crises are triggered by febrile infections; they become less frequent with age but are not restricted to childhood. Complete recovery is typical, but ALF crises can be fatal. Antipyretic therapy and induction of anabolism including glucose and parenteral lipids effectively ameliorates the course of liver crises. Patients’ fibroblasts showed an increased sensitivity to high temperature at protein and functional level and a disturbed tethering of vesicles, pointing at a defect of intracellular transport between the endoplasmic reticulum and Golgi.
Conclusions
Mutations in
NBAS
cause a complex disease with a wide clinical spectrum ranging from isolated RALF to a multisystemic phenotype. Thermal susceptibility of the syntaxin 18 complex is the basis of fever dependency of ALF episodes. NBAS deficiency is the first disease related to a primary defect of retrograde transport. Identification of NBAS deficiency allows optimized therapy of liver crises and even prevention of further episodes.
Materials can be made multifunctional by embedding them with living cells that perform sensing, synthesis, energy production, and physical movement. A challenge is that the conditions needed for ...living cells are not conducive to materials processing and require continuous water and nutrients. Here, we present a three dimensional (3D) printer that can mix material and cell streams to build 3D objects. Bacillus subtilis spores were printed within the material and germinated on its exterior surface, including spontaneously in new cracks. The material was resilient to extreme stresses, including desiccation, solvents, osmolarity, pH, ultraviolet light, and γ-radiation. Genetic engineering enabled the bacteria to respond to stimuli or produce chemicals on demand. As a demonstration, we printed custom-shaped hydrogels containing bacteria that can sense or kill Staphylococcus aureus, a causative agent of infections. This work demonstrates materials endued with living functions that can be used in applications that require storage or exposure to environmental stresses.
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