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Applied and Environmental Microbiology Dec 2023Many parameters affect phage-bacteria interaction. Some of these parameters depend on the environment in which the bacteria are present. Anaerobiosis effect on phage...
Many parameters affect phage-bacteria interaction. Some of these parameters depend on the environment in which the bacteria are present. Anaerobiosis effect on phage infection in facultative anaerobic bacteria has not yet been studied. The absence of oxygen triggers metabolic changes in facultative bacteria and this affects phage infection and viral life cycle. Understanding how an anaerobic environment can alter the behavior of phages during infection is relevant for the phage therapy success.
Topics: Bacteriophages; Anaerobiosis; Bacteria
PubMed: 37966212
DOI: 10.1128/aem.01491-23 -
Water Research Aug 2023Anaerobic digestion processes can generate renewable energy in the form of biogas while treating organic wastewater. The generation of biogas within anaerobic digestion... (Review)
Review
Anaerobic digestion processes can generate renewable energy in the form of biogas while treating organic wastewater. The generation of biogas within anaerobic digestion systems is directly linked to the mixing conditions inside the reactors. In high-rate reactors such as the upflow anaerobic sludge blanket (UASB) reactor, the expanded granular sludge bed (EGSB) reactor and the internal circulation (IC) reactor, the hydrodynamic behaviour will depend on the interactions between the wastewater, the biogas, and the biomass granules. Over the past few years, various researchers have used computational fluid dynamics (CFD) to study the hydrodynamic behaviour in these types of reactors. This review aims to present and critically discuss the state of the art in the use of CFD applied to anaerobic granular sludge reactors (AGSRs). It briefly introduces and discusses the various aspects of modelling. It also reviews the various papers which used CFD to model these reactors and critically analyses the models used for the simulations in terms of general approaches and single-phase vs multiphase studies. The methods used in the validation of the CFD models are also described and discussed. Based on the findings, the challenges and future perspectives for the CFD modelling of AGSRs are discussed and gaps in the knowledge are identified.
Topics: Sewage; Wastewater; Anaerobiosis; Hydrodynamics; Waste Disposal, Fluid; Biofuels
PubMed: 37354837
DOI: 10.1016/j.watres.2023.120220 -
Biotechnology Advances Dec 2023Sulfide ions are regarded to be toxic to microorganisms in engineered methanogenic systems (EMS), where organic substances are anaerobically converted to products such... (Review)
Review
Sulfide ions are regarded to be toxic to microorganisms in engineered methanogenic systems (EMS), where organic substances are anaerobically converted to products such as methane, hydrogen, alcohols, and carboxylic acids. A vast body of research has addressed solutions to mitigate process disturbances associated with high sulfide levels, yet the established paradigm has drawn the attention away from the multifaceted sulfide interactions with minerals, organics, microbial interfaces and their implications for performance of EMS. This brief review brings forward sulfide-derived pathways other than toxicity and with potential significance for anaerobic organic matter degradation. Available evidence on sulfide reactions with organic matter, interventions with key microbial metabolisms, and interspecies electron transfer are critically synthesized as a guidance for comprehending the sulfide effects on EMS apart from the microbial toxicity. The outcomes identify existing knowledge gaps and specify future research needs as a step forward towards realizing the potential of sulfide-derived mechanisms in diversifying and optimizing EMS applications.
Topics: Electron Transport; Sulfides; Methane; Anaerobiosis
PubMed: 37666371
DOI: 10.1016/j.biotechadv.2023.108249 -
Bioresource Technology Aug 2022In regions highly dependent on fossil fuels imports, biomethane represents a promising biofuel for the transition to a bio-based circular economy. While biomethane is...
In regions highly dependent on fossil fuels imports, biomethane represents a promising biofuel for the transition to a bio-based circular economy. While biomethane is typically produced via anaerobic digestion and upgrading, biomethanation of the synthesis gas (syngas) derived from the gasification of recalcitrant solid waste has emerged as a promising alternative. This work presents a comprehensive and in-depth analysis of the state-of-the-art and most recent advances in the field, compiling the potential of this technology along with the bottlenecks requiring further research. The key design and operational parameters governing syngas production and biomethanation (e.g. organic feedstock, gasifier design, microbiology, bioreactor configuration, etc.) are critically analysed.
Topics: Anaerobiosis; Biofuels; Bioreactors; Gases; Methane; Solid Waste
PubMed: 35680093
DOI: 10.1016/j.biortech.2022.127436 -
Bioresource Technology Jul 2021Hydrothermal pretreatment (HTP) (Hot water extraction (HWE) and steam pretreatment) and pyrolysis have the potential to liquefy lignocellulosic biomass. HTP produces... (Review)
Review
Hydrothermal pretreatment (HTP) (Hot water extraction (HWE) and steam pretreatment) and pyrolysis have the potential to liquefy lignocellulosic biomass. HTP produces hydrolysate, consisting mainly of solubilized hemicellulose, while pyrolysis produces aqueous pyrolysis liquid (APL). The liquid products, either as main products or by-product, can be used as anaerobic digestion (AD) feeds, overcoming shortcomings of solid-state AD (SS-AD). This paper reviews HWE, steam pretreatment, and pyrolysis pretreatment methods used to liquefy lignocellulosic biomass, AD of liquefied products, effects of inhibition from intermediate by-products such as furan and phenolic compounds, and pretreatment tuning to increase methane yield. HTP, focusing on methane production, produces less inhibitory compounds when carried out at moderate temperatures. APL is a challenging feed for AD due to its complexity, including various inhibitory substances. Pre-treatment of biomass before pyrolysis, adaptation of microorganism to inhibitors, and additives, such as biochar, may help the AD cultures cope with inhibitors in APL.
Topics: Anaerobiosis; Biofuels; Biomass; Lignin; Methane; Pyrolysis
PubMed: 33849751
DOI: 10.1016/j.biortech.2021.125068 -
Journal of Environmental Management Nov 2018Volatile fatty acids (VFAs) are a class of largely used compounds in the chemical industry, serving as starting molecules for bioenergy production and for the synthesis... (Review)
Review
Volatile fatty acids (VFAs) are a class of largely used compounds in the chemical industry, serving as starting molecules for bioenergy production and for the synthesis of a variety of products, such as biopolymers, reduced chemicals and derivatives. Because of the huge amounts of food waste generated from household and processing industry, 47 and 17 million tons per year respectively only in the EU-28 Countries, food wastes can be the right candidate for volatile fatty acids production. This review investigates all the major topics involved in the optimization of VFAs production from food wastes. Regarding the best operative conditions for the anaerobic fermenter controlled pH in the neutral range (6.0-7.0), short HRT (lower than 10 days), thermophilic temperatures and an organic loading rate of about 10 kgVS/md, allowed for an increase in the VFAs concentration between 10 and 25%. It was also found that additions of mineral acids, from 0.5 to 3.0%, and thermal pretreatment in the range 140-170 °C increase the organic matter solubilisation. Applications of VFAs considered in this study were biofuels and bioplastics production as well as nutrients removal in biological wastewater treatment processes.
Topics: Anaerobiosis; Biofuels; Bioreactors; Fatty Acids, Volatile; Food; Hydrogen-Ion Concentration; Wastewater
PubMed: 30121464
DOI: 10.1016/j.jenvman.2018.08.039 -
Journal of the International Society of... Jan 2021Creatine (CR) and sodium bicarbonate (SB) alone improve anaerobic performance. However, the ergogenic effects of CR and SB co-ingestion on taekwondo anaerobic... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Creatine (CR) and sodium bicarbonate (SB) alone improve anaerobic performance. However, the ergogenic effects of CR and SB co-ingestion on taekwondo anaerobic performance remains unknown.
METHODS
Forty trained taekwondo athletes (21 ± 1 y.; 180.5 ± 7.3 cm; 72.7 ± 8.6 kg) were randomized to: (i) CR and SB (CR + SB; 20 g of CR+ 0.5 g·kg·d of SB), (ii) CR, (iii) SB, (iv) placebo (PLA), or (v) control (CON) for 5 days. Before and after supplementation, participants completed 3 bouts of a Taekwondo Anaerobic Intermittent Kick Test (TAIKT) to determine changes in peak power (PP), mean power (MP), and fatigue index (FI). Blood lactate (BL) was measured before, immediately following, and 3 min post-TAIKT.
RESULTS
PP and MP increased over time (P < 0.05) following CR + SB, CR, and SB ingestion, with no changes in the PLA or CON groups. There was a greater increase over time in MP following CR + SB (Absolute Δ: 1.15 ± 0.28 W∙kg) compared to CR (Absolute Δ: 0.43 ± 0.33 W∙kg; P < 0.001) and SB (Absolute Δ: 0.73 ± 0.24 W∙kg; P = 0.03). There were no significant time and condition effect for FI (P > 0.05). BL increased following exercise across all groups; however, CR + SB and SB post-exercise BL was lower compared to CR, PLA, and CON (P < 0.05).
CONCLUSION
Short-term CR and SB alone enhance TAIKT performance in trained taekwondo athletes. Co-ingestion of CR and SB augments MP compared to CR and SB alone, with similar PP improvements.
Topics: Anaerobiosis; Analysis of Variance; Athletic Performance; Creatine; Dietary Supplements; Energy Metabolism; Fatigue; Humans; Lactic Acid; Male; Martial Arts; Performance-Enhancing Substances; Physical Exertion; Polysaccharides; Sodium Bicarbonate; Young Adult
PubMed: 33478522
DOI: 10.1186/s12970-021-00407-7 -
Water Research Oct 2020Hydroxylamine is a key intermediate in several biological reactions of the global nitrogen cycle. However, the role of hydroxylamine in anammox is still not fully...
Hydroxylamine is a key intermediate in several biological reactions of the global nitrogen cycle. However, the role of hydroxylamine in anammox is still not fully understood. In this work, the impact of hydroxylamine (also in combination with other substrates) on the metabolism of a planktonic enrichment culture of the anammox species Ca. Kuenenia stuttgartiensis was studied. Anammox bacteria were observed to produce ammonium both from hydroxylamine and hydrazine, and hydroxylamine was consumed simultaneously with nitrite. Hydrazine accumulation - signature for the presence of anammox bacteria - strongly depended on the available substrates, being higher with ammonium and lower with nitrite. Furthermore, the results presented here indicate that hydrazine accumulation is not the result of the inhibition of hydrazine dehydrogenase, as commonly assumed, but the product of hydroxylamine disproportionation. All kinetic parameters for the identified reactions were estimated by mathematical modelling. Moreover, the simultaneous consumption and growth on ammonium, nitrite and hydroxylamine of anammox bacteria was demonstrated, this was accompanied by a reduction in the nitrate production. Ultimately, this study advances the fundamental understanding of the metabolic versatility of anammox bacteria, and highlights the potential role played by metabolic intermediates (i.e. hydroxylamine, hydrazine) in shaping natural and engineered microbial communities.
Topics: Anaerobiosis; Bacteria; Hydroxylamine; Hydroxylamines; Nitrites; Oxidation-Reduction
PubMed: 32739592
DOI: 10.1016/j.watres.2020.116188 -
Food Microbiology May 2022Microbial communities associated with coffee fermentation have been widely investigated. However, few reports about self-induced anaerobiosis fermentation (SIAF) on...
Microbial communities associated with coffee fermentation have been widely investigated. However, few reports about self-induced anaerobiosis fermentation (SIAF) on microbial diversity and the chemical and sensory profile of coffees grown under different environmental conditions have been studied. This study evaluated the microbial, chemical, and sensorial profile of the natural and pulped coffee fermented with and without induced anaerobiosis. The microbial diversity was determined by plating and next-generation sequencing, the chemical profile through 1H NMR and chemometrics analysis, and sensory analysis was conducted by Temporal Dominance of Sensations (TDS). Three hundred and eighty microorganisms were isolated; 149 mesophilic bacteria, 147 lactic acid bacteria, and 84 yeasts. Hanseniaspora uvarum, Lactiplantibacillus plantarum, Leuconostoc mesenteroides, and Weissella cibaria were identified in Monte Carmelo, Três Pontas, Carmo de Minas, and Lajinha in Minas Gerais, Brazil. New generation sequencing (NGS) analysis identified a high yeast species diversity (74). Some metabolites such as chlorogenic acid, sucrose, lactic acid, and trigonelline were identified in fermented coffees with the joint analysis of NMR and the loadings of PC1. Monte Carmelo coffees processed by the pulped method stood out sensorially showed a higher dominance rate for woody, herbaceous and fruity attributes. The SIAF positively impacts microbial behavior, resulting in coffees with a more intensified fruity attribute.
Topics: Anaerobiosis; Chemometrics; Coffee; Fermentation; Microbiota
PubMed: 35082079
DOI: 10.1016/j.fm.2021.103962 -
Animal Models and Experimental Medicine Dec 2021Oxygen is one of the important substances for the survival of most life systems on the earth, and plateau and underground burrow systems are two typical hypoxic... (Review)
Review
Oxygen is one of the important substances for the survival of most life systems on the earth, and plateau and underground burrow systems are two typical hypoxic environments. Small mammals living in hypoxic environments have evolved different adaptation strategies, which include increased oxygen delivery, metabolic regulation of physiological responses and other physiological responses that change tissue oxygen utilization. Multi-omics predictions have also shown that these animals have evolved different adaptations to extreme environments. In particular, vascular endothelial growth factor (VEGF) and erythropoietin (EPO), which have specific functions in the control of O delivery, have evolved adaptively in small mammals in hypoxic environments. Naked mole-rats and blind mole-rats are typical hypoxic model animals as they have some resistance to cancer. This review primarily summarizes the main living environment of hypoxia tolerant small mammals, as well as the changes of phenotype, physiochemical characteristics and gene expression mode of their long-term living in hypoxia environment.
Topics: Adaptation, Physiological; Anaerobiosis; Animals; Mole Rats; Vascular Endothelial Growth Factor A
PubMed: 34977483
DOI: 10.1002/ame2.12183