SEARCH · Engineering Papers

Results for “microbial systems”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 325 records · Page 18

All sources NASA NTRS DOE OSTI

NASA NTRS1992

Human life support during interplanetary travel and domicile. VI - Generic modular flow schematic for hybrid physical/chemical-biological life support systems

An extension is proposed for the NASA Space Exploration Initiative's Generic Modular Flow Schematics for physical/chemical life support systems which involves the addition of biological processes. The new system architecture includes plant, microbial, and animal habitat, as well as the human habitat subsystem. Major Feedstock Production and Food Preparation and Packaging components have also been incorporated. Inedible plant, aquaculture, microbial, and animal solids are processed for recycling.

Ganapathi, Gani B.↗

NASA NTRS1995

Thermal Springs and the Search for Past Life on Mars

Ancient thermal spring sites have several features which make them significant targets in a search for past life. Chemical (including redox) reactions in hydrothermal systems possibly played a role in the origin of life on Earth and elsewhere. Spring waters frequently contain reduced species (sulfur compounds, Fe(sup +2), etc.) which can provide chemical energy for organic synthesis. Relatively cool hydrothermal systems can sustain abundant microbial life (on Earth, at temperatures greater than 110 C). A spring site on Mars perhaps might even have maintained liquid water for periods sufficiently long to sustain surface-dwelling biota had they existed. On Earth, a variety of microbial mat communities can be sampled along the wide range of temperatures surrounding the spring, thus offering an opportunity to sample a broad biological diversity. Thermal spring waters frequently deposit minerals (carbonates, silica, etc.) which can entomb and preserve both fluid inclusions and microbial communities. These deposits can be highly fossiliferous and preserve biological inclusions for geologically long periods of time. Such deposits can cover several square km on Earth, and their distinctive mineralogy (e.g., silica- and/or carbonate-rich) can contrast sharply with that of the surrounding region. As with Martian volcanoes, Martian thermal spring complexes and their deposits might typically be much larger than their counterparts on Earth. Thus Martian spring deposits are perhaps readily detectable and even accessible. Elysium Planitia is an example of a promising region where hydrothermal activity very likely remobilized ground ice and sustained springs.

DesMarais, D. J.↗

NASA NTRS2002

Comparative ecology of H2 cycling in sedimentary and phototrophic ecosystems

The simple biochemistry of H2 is critical to a large number of microbial processes, affecting the interaction of organisms with each other and with the environment. The sensitivity of each of these processes to H2 can be described collectively, through the quantitative language of thermodynamics. A necessary prerequisite is to understand the factors that, in turn, control H2 partial pressures. These factors are assessed for two distinctly different ecosystems. In anoxic sediments from Cape Lookout Bight (North Carolina, USA), H2 partial pressures are strictly maintained at low, steady-state levels by H2-consuming organisms, in a fashion that can be quantitatively predicted by simple thermodynamic calculations. In phototrophic microbial mats from Baja California (Mexico), H2 partial pressures are controlled by the activity of light-sensitive H2-producing organisms, and consequently fluctuate over orders of magnitude on a daily basis. The differences in H2 cycling can subsequently impact any of the H2-sensitive microbial processes in these systems. In one example, methanogenesis in Cape Lookout Bight sediments is completely suppressed through the efficient consumption of H2 by sulfate-reducing bacteria; in contrast, elevated levels of H2 prevail in the producer-controlled phototrophic system, and methanogenesis occurs readily in the presence of 40 mM sulfate.

Review, Tutorial↗

NASA NTRS2005

Microbial Air and Surface Monitoring Results from International Space Station Samples

Over the course of long-duration spaceflight, spacecraft develop a microbial ecology that directly interacts with the crew of the vehicle. While most microorganisms are harmless or beneficial to the inhabitants of the vehicle, the presence of medically significant organisms appearing in this semi-closed environment could adversely affect crew health and performance. The risk of exposure of the crew to medically significant organisms during a mission is estimated using information gathered during nominal and contingency environmental monitoring. Analysis of the air and surface microbiota in the habitable compartments of the International Space Station (ISS) over the last four years indicate a high presence of Staphylococcus species reflecting the human inhabitants of the vehicle. Generally, air and surface microbial concentrations are below system design specifications, suggesting a lower risk of contact infection or biodegradation. An evaluation of sample frequency indicates a decrease in the identification of new species, suggesting a lower potential for unknown microorganisms to be identified. However, the opportunistic pathogen, Staphylococcus aureus, has been identified in 3 of the last 5 air samples and 5 of the last 9 surface samples. In addition, 47% of the coagulase negative Staphylococcus species that were isolated from the crew, ISS, and its hardware were found to be methicillin resistance. In combination, these observations suggest the potential of methicillin resistant infectious agents over time.

Ott, C. Mark↗

NASA NTRS2013

Method for Reduction of Silver Biocide Plating on Metal Surfaces

Silver ions in aqueous solutions (0.05 to 1 ppm) are used for microbial control in water systems. The silver ions remain in solution when stored in plastic containers, but the concentration rapidly decreases to non-biocidal levels when stored in metal containers. The silver deposits onto the surface and is reduced to non-biocidal silver metal when it contacts less noble metal surfaces, including stainless steel, titanium, and nickel-based alloys. Five methods of treatment of contact metal surfaces to deter silver deposition and reduction are proposed: (1) High-temperature oxidation of the metal surface; (2) High-concentration silver solution pre-treatment; (3) Silver plating; (4) Teflon coat by vapor deposition (titanium only); and (5) A combination of methods (1) and (2), which proved to be the best method for the nickel-based alloy application. The mechanism associated with surface treatments (1), (2), and (5) is thought to be the development of a less active oxide layer that deters ionic silver deposition. Mechanism (3) is an attempt to develop an equilibrium ionic silver concentration via dissolution of metallic silver. Mechanism (4) provides a non-reactive barrier to deter ionic silver plating. Development testing has shown that ionic silver in aqueous solution was maintained at essentially the same level of addition (0.4 ppm) for up to 15 months with method (5) (a combination of methods (1) and (2)), before the test was discontinued for nickel-based alloys. Method (1) resulted in the maintenance of a biocidal level (approximately 0.05 ppm) for up to 10 months before that test was discontinued for nickel-based alloys. Methods (1) and (2) used separately were able to maintain ionic silver in aqueous solution at essentially the same level of addition (0.4 ppm) for up to 10 months before the test was discontinued for stainless steel alloys. Method (3) was only utilized for titanium alloys, and was successful at maintaining ionic silver in aqueous solution at essentially the same level of addition (0.4 ppm) for up to 10 months before the test was discontinued for simple flat geometries, but not for geometries that are difficult to Teflon coat.

Steele, John↗

DOE OSTI2021

Methods for identifying interactions amongst microorganisms

Disclosed herein are methods, compositions, and systems for determining specific microbial taxa, within a complex consortia of mixed taxa, which are interacting with each other in an environment of interest. In some embodiments, after diluting a sample comprising multiple different taxa of microorganisms, dilutions of the sample are cultivated for determining taxonomic information and interactions of multiple taxa of microorganisms in the sample.

Justice, Nicholas B.↗

DOE OSTI2021

Green hydrogen from microalgal liquefaction byproducts with ammonia recovery and effluent recycle for developing circular processes

Hydrothermal liquefaction is a promising technology for microalgae-based biofuel production. However, hydrothermal liquefaction’s aqueous wastes have little established reuse, and contain significant fractions of toxic ammoniacal nitrogen. Careful reuse of this waste can assure microalgae-based biofuels are produced with less environmental impact and larger energy efficiency. Microbial electrolysis cells were investigated to valorize this waste product by converting the leftover organics into hydrogen and remove ammonia. Waste hydrothermal liquefaction aqueous phase from two microalgal strains, Tetraselmis sp. and Chlorella sp. were used as feedstocks for hydrogen production in microbial electrolysis cells. Chlorella and Tetraselmis aqueous phase-fed microbial electrolysis cells reach an average current density of 5.1 ± 0.19 A/m 2 and 3.8 ± 0.08 A/m 2 . Compound removal rates and mass removal percentages were also investigated for each feedstock. Additionally, acetic acid, propionic acid, ethanol, and glycerol were effectively removed from the aqueous byproduct. Further, microbial electrolysis cells separated up to 34.3% of ammoniacal nitrogen present in the aqueous phase. Charge transfer analysis indicated that proton transfer, not ammonium transfer, contributed to the majority of the hydrogen production in the cathode. Finally, the microbial electrolysis cell effluent was reused to grow the same microalgal strains, leading to the development of a circular biofuel production system. Microalgae regrowth studies using microbial electrolysis cell effluent showed nearly complete removal of total organic carbon, but significantly less removal of total nitrogen. Tetraselmis sp. growth occurred with the Tetraselmis-derived MEC effluent, however, the control medium without effluent produced the most growth. These findings support the possibility of a circular biofuel framework using MECs, but additional constraints, including the removal of inorganic contaminants, are necessary to realize the circular processes.

09 BIOMASS FUELS↗

NASA NTRSDate not supplied

Hot Water, Cold Reality: Experimental Analysis of Sorption Constraints in Iodine Filtration Media Under Heated-Water Conditions

Iodine has been widely employed as a residual biocide in potable water applications during crewed missions. Unlike other biocides, it is essential to remove iodine from drinking water prior to consumption, as its biocidal concentration raises health concerns. Consequently, effectively removing iodine species from water is a critical step in potable water processing. Although the non-biocided heated leg has not violated microbial specifications on the International Space Station, any wetted volume lacking biocide presents potential risks for long‑duration exploration missions and for systems that are sensitive to microbial growth/contamination. Recent assessments indicate, however, that iodine‑removal performance may degrade under elevated temperature conditions, such as those required for dispensing hot water for food preparation. This reduction in efficacy appears to stem from both the potential physical degradation of filtration media and the temperature‑dependent behavior of adsorption processes. To investigate the influence of water temperature on the efficacy of filtration media for iodine removal, a series of adsorption capacity tests were conducted at both room temperature and elevated temperatures (90 °C). These experiments aimed to benchmark the performance of the adsorbents that constitute the ACTEX filter in the ISS’s potable water dispenser. The findings of this study provide critical insights into the iodine filtration process, verify the potential performance shortfall under elevated temperature conditions, and establish the basis for defining new absorbent requirements to ensure reliable iodine removal in future mission architectures.

iodine↗

NASA NTRSDate not supplied

Hot Water, Cold Reality: Experimental Analysis of Sorption Constraints in Iodine Filtration Media Under Heated-Water Conditions

drinking water↗

DOE OSTI2021

Systematic investigations on iron cycling in phosphorus/siderophore systems: Synergism or antagonism?

Synergisms between microbial exudates on Fe (hydr)oxide dissolution as an effective Fe acquisition pathway have been recently addressed and vigorously debated. However, Fe liberation mechanisms and where siderophores and phosphorus (P) coexist received little attentions. Current study systematically investigated ferrihydrite dissolution in the presence of desferrioxamine B (DFOB) (a kind of fungally-derived siderophores) and inorganic/organic phosphorus (orthophosphate, Pi; myo-inositol hexaphosphate, IHP), as a function of solute pH, reaction time and reagent content. Reacted solids were characterized by N 2 -BET adsorption, zeta (ζ) potential analysis, sequential extraction analysis (SEDEX), field emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), micro Raman spectroscopy and attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR). Our results indicate that upon reaction with P-only or (DFOB + P) systems, interfacial complexation partially switched from monolayer bidentate-binuclear surface complexes to ternary complexes, or laterally transformed into amorphous Fe–P precipitates. The Fe-Pi complex precipitated more readily under acidic conditions, and Fe-IHP complex preferentially nucleated in neutral-alkaline environments. Phosphorus slightly promoted Fe release from minerals and fixation to the leached layer or interfacial liquid zone initially, but subsequently prevented further attacks from protons and DFOB. The co-effects of P and DFOB likely correspond to two successive scenarios: 1) DFOB is preferentially attracted toward ferrihydrite surfaces by negative electrical fields induced by adsorbed phosphorus and can act synergistically with labile P–Fe complexes, resulting in intensive temporal dissolution of Fh; 2) subsequent Fe shuttling to DFOB can be prohibited by stabilized, passive P/Fe–P layers. Finally, our results emphasize the antagonism between P compounds and siderophores (i.e., DFOB here) on ferrihydrite dissolution to improve understanding of the biologically-mediated Fe cycling in natural systems.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2020

Microanalysis of Primary Biological Particles from Model Grass over Its Life Cycle

Airborne biological aerosols are an integral part of the atmosphere–biosphere interface and significantly impact the environment and Earth’s climate. Primary biological particles such as fungal spores, bacteria, and fragments of plant debris are emitted directly from the biosphere into the atmosphere. The phyllosphere (aboveground plant surfaces) is one of the major habitats for different microbes. Here, atmospheric emissions of primary biological particles from model grass Brachypodium distachyon were monitored by online particle number concentration counting at eight principal growth stages starting from leaf development to senescence. Particles collected at each of the growth stages were then characterized using microspectroscopy techniques. Our findings indicate that the morphological and compositional characteristics of emitted biological particles are highly variable at the different growth stages. We identified fungal spores as the most abundant biological particles in the heading stage, while bacteria were most abundant in the flowering and fruit development stages. Understanding differences in the composition and morphology of biological particles during the plant life cycle provides more accurate and reliable insights on structural, functional, and biochemical properties of plant systems, as well as their interactions with microbial communities. This study also provides insights into Earth geoscience system models that represent primary biological particle emissions from the biosphere.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

NASA NTRS2019

Using the NASA GeneLab Data System to Study the Metagenomes of Spaceships and Their Occupants

With humans pushing to live further off Earth for longer periods of time, it is increasingly important to understand the changes that occur in biological systems during spaceflight whether these be astronauts, their microbial commensals, or their plant-based life support systems. In a three-part presentation, we discuss GeneLab and recent discoveries regarding the microbiota of spacecrafts and space-flown animals. Part 1: GeneLab: Open Science for Life in Space, Jonathan Galazka, NASA Ames Research Center To accelerate the pace of discovery from precious spaceflight biological experiments, NASA as develop the GeneLab data system (genelab.nasa.gov), which allows unfettered access to omics data from spaceflight and spaceflight relevant experiments. GeneLab houses metagenomic datasets from spacecraft and relevant spacecraft models. Users can download this data and associated metadata to make new discoveries about how microbial communities may change and adapt to spaceflight.

Galazka, Jonathan M.↗

NASA NTRSDate not supplied

DirectINJECT: Dosing Systems for Concentrated Liquid Biocides

Reliable and mass-efficient techniques for biocide dosing are necessary to enable residual microbial control in spacecraft potable water systems. DirectINJECT is an approach to provide ultra-low flow rate injection of stable aqueous biocide concentrate solution (e.g., highly soluble silver salt). This method has the benefit of low consumable mass and is insensitive to the chemistry of the target water. With a 40 g Ag+/liter solution, required dosing rates would be ~1 μl/minute during water processing (for a system similar to the ISS WPA), requiring only approximately 20 ml/crew-year of concentrate. The performance of three dosing systems were identified and characterized: pressure-driven flow through a robust micro-capillary tube with a solenoid valve shut-off, a miniature peristaltic pump, and a multi-piston pump with integrated valving. Several potential system reliability concerns are addressed including prevention or segregation of gas bubbles in the concentrate reservoirs as well as long-term materials compatibility and mechanical life.

silver↗

DOE OSTI2025

Integrating microbial communities into algal biotechnology: a pathway to enhanced commercialization

Microalgae are increasingly recognized for their potential in wastewater treatment and the sustainable production of feedstock for fuel, feed, food, and other bioproducts. Like conventional agricultural systems, algal cultivation involves complex microbial communities. However, despite their pivotal role in cultivation outcomes, especially at the commodity-scale, the critical interactions between microalgae and their microbiomes are often overlooked. Here we synthesize current knowledge on the taxonomic diversity, ecological roles, and biotechnological potential of algal microbiomes, with a focus on their interactions with algal hosts through nutrient exchange, growth modulation, pathogen defense, and environmental conditioning. We also examine how environmental factors such as nutrient availability, salinity, and temperature influence these interactions. Advances in microbiome engineering, including synthetic biology and ecological approaches, offer opportunities to enhance beneficial algal-microbiome interactions, thereby improving growth, resilience, and yield. These advancements could lead to more sustainable and economically viable microalgae cultivation, with far-reaching implications for environmental management and biotechnological innovation. By addressing key economic and environmental barriers, microbiome engineering holds transformative potential to revolutionize large-scale algae cultivation and provide sustainable solutions to global challenges.

Microbiology↗

DOE OSTI2023

Scale-up and techno-economic analysis of microbial electrolysis cells for hydrogen production from wastewater

Microbial electrolysis cells (MECs) have demonstrated high-rate H 2 production while concurrently treating wastewater, but the transition in scale from laboratory research to systems that can be practically applied has encountered challenges. It has been more than a decade since the first pilot-scale MEC was reported, and in recent years, many attempts have been made to overcome the barriers and move the technology to the market. This study provided a detailed analysis of MEC scale-up efforts and summarized the key factors that should be considered to further develop the technology. We compared the major scale-up configurations and systematically evaluated their performance from both technical and economic perspectives. We characterized how system scale-up impacts the key performance metrics such as volumetric current density and H 2 production rate, and we proposed methods to evaluate and optimize system design and fabrication. In addition, preliminary techno-economic analysis indicates that MECs can be profitable in many different market scenarios with or without subsidies. Here, we also provide perspectives on future development needed to transition MEC technology to the marketplace.

42 ENGINEERING↗

DOE OSTI2021

Metagenomic and metatranscriptomic analysis reveals enrichment for xenobiotic‐degrading bacterial specialists and xenobiotic‐degrading genes in a Canadian Prairie two‐cell biobed system

Summary Biobeds are agriculture‐based bioremediation tools used to safely contain and microbially degrade on‐farm pesticide waste and rinsate, thereby reducing the negative environmental impacts associated with pesticide use. While these engineered ecosystems demonstrate efficient pesticide removal, the microbiomes in these environments remain largely understudied both taxonomically and functionally. This study used metagenomic and metatranscriptomic techniques to characterize the microbial community in a two‐cell Canadian biobed system before and after a field season of pesticide application. These culture‐independent approaches identified an enrichment of xenobiotic‐degrading bacteria, such as Afipia , Sphingopyxis and Pseudomonas , and enrichment and transcription of xenobiotic‐degrading genes, such as peroxidases, oxygenases, and hydroxylases, among others; we were able to directly link the transcription of these genes to Pseudomonas , Oligotropha , Mesorhizobium , Rhodopseudomonas , and Stenotrophomonas taxa.

Russell, Jennifer N.↗

NASA NTRS2010

Colorimetric Solid Phase Extraction (CSPE): Using Color to Monitor Spacecraft Water Quality

In August 2009, an experimental water quality monitoring kit based on Colorimetric Solid Phase Extraction (CSPE) technology was delivered to the International Space Station (ISS). The kit, called the Colorimetric Water Quality Monitoring Kit (CWQMK), was launched as a Station Development Test Objective (SDTO) experiment to evaluate the suitability of CSPE technology for routine use monitoring water quality on the ISS. CSPE is a sorption-spectrophotometric technique that combines colorimetric reagents, solid-phase extraction, and diffuse reflectance spectroscopy to quantify trace analytes in water samples. In CSPE, a known volume of sample is metered through a membrane disk that has been impregnated with an analyte-specific colorimetric reagent and any additives required to optimize the formation of the analyte-reagent complex. As the sample flows through the membrane disk, the target analyte is selectively extracted, concentrated, and complexed. Formation of the analyte-reagent complex causes a detectable change in the color of the membrane disk that is proportional to the amount of analyte present in the sample. The analyte is then quantified by measuring the color of the membrane disk surface using a hand-held diffuse reflectance spectrophotometer (DRS). The CWQMK provides the capability to measure the ionic silver (Ag +) and molecular iodine (I2) in water samples on-orbit. These analytes were selected for the evaluation of CSPE technology because they are the biocides used in the potable water storage and distribution systems on the ISS. Biocides are added to the potable water systems on spacecraft to inhibit microbial growth. On the United States (US) segment of the ISS molecular iodine serves as the biocide, while the Russian space agency utilizes silver as a biocide in their systems. In both cases, the biocides must be maintained at a level sufficient to control bacterial growth, but low enough to avoid any negative effects on crew health. For example, the presence of high levels of iodine in water can cause taste and odor issues that result in decreased water consumption by the crew. There are also concerns about potential impacts on thyroid function following exposure to high levels of iodine. With silver, there is a risk of developing argyria, an irreversible blue-gray discoloration of the skin, associated with long term consumption of water containing high concentrations of silver. The need to ensure that safe, effective levels of biocide are maintained in the potable water systems on the ISS provides a perfect platform for evaluating the suitability of CSPE technology for in-flight water quality monitoring. This paper provides an overview of CSPE technology and details on the silver and iodine methods used in the CWQMK. It also reports results obtained during in-flight analyses performed with the CWQMK and briefly discusses other potential applications for CSPE technology in both the spacecraft and terrestrial environments.

Gazda, Daniel B.↗

DOE OSTI2022

SynMADE: synthetic microbiota across diverse ecosystems

The last two decades have witnessed rapid advances in engineering individual microbial strains to produce biochemicals and biomaterials. Furthermore, engineering microbial consortia has been relatively slow. Using systems and synthetic biology approaches, researchers have been developing tools for engineering complex microbiota. In this article, I discuss future directions and visions regarding developing microbiota as a biomanufacturing host. Specifically, I propose that we can develop the soil microbial community itself as a huge bioreactor. Ultimately, researchers will provide a generalizable system that enables us to understand microbial consortium’s interaction and metabolism at diverse temporal and spatial scales to address global problems, including the climate crisis, food inequality, waste issue, and sustainable bioproduction.

59 BASIC BIOLOGICAL SCIENCES↗