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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 -
Current Opinion in Biotechnology Jun 2001Novel dehalogenases have been identified recently in various bacteria that utilise halogenated substrates. X-ray studies and sequence analysis have revealed insight into... (Review)
Review
Novel dehalogenases have been identified recently in various bacteria that utilise halogenated substrates. X-ray studies and sequence analysis have revealed insight into the molecular mechanisms of hydrolytic dehalogenases. Furthermore, genetic and biochemical studies have indicated that reductive dehalogenases are extra-cytoplasmic corrinoid-containing iron-sulphur proteins. Sequence analysis and mutagenesis studies indicate that several dehalogenases are homologous to enzymes that carry out transformations on non-halogenated substrates.
Topics: Aerobiosis; Anaerobiosis; Bacteria; Bacterial Physiological Phenomena; Biodegradation, Environmental; Catalysis; Hydrocarbons, Halogenated; Hydrolases
PubMed: 11404103
DOI: 10.1016/s0958-1669(00)00208-1 -
Minerva Anestesiologica Apr 2003The detection of tissue hypoxia and its correction is one of the aim of the hemodynamic monitoring. Classical hemodynamic variable often fail to achieve this goal.... (Review)
Review
The detection of tissue hypoxia and its correction is one of the aim of the hemodynamic monitoring. Classical hemodynamic variable often fail to achieve this goal. Lactate measurements may be a good indicator of tissue hypoxia. Selected review of the articles on lactate in critically ill patients. Tissue hypoxia is associated with an increase in blood lactate levels. However lactate can also be produced in aerobic conditions, in inflammated tissues, and lactate clearance is often decreased in critically ill patients. Whatever its origin, blood lactate levels have a strong predictive value. The interpretation of blood lactate levels is difficult. Nevertheless, monitoring blood lactate levels can be useful to detect tissue hypoxia and to monitor the effects of therapy.
Topics: Acidosis, Lactic; Aerobiosis; Anaerobiosis; Humans; Lactates; Prognosis; Sepsis
PubMed: 12766720
DOI: No ID Found -
Cellular & Molecular Biology Letters Jul 2023The preference for glucose oxidative mode has crucial impacts on various physiological activities, including determining stem cell fate. External mechanical factors can...
BACKGROUND
The preference for glucose oxidative mode has crucial impacts on various physiological activities, including determining stem cell fate. External mechanical factors can play a decisive role in regulating critical metabolic enzymes and pathways of stem cells. Periodontal ligament stem cells (PDLSCs) are momentous effector cells that transform mechanical force into biological signals during the reconstruction of alveolar bone. However, mechanical stimuli-induced alteration of oxidative characteristics in PDLSCs and the underlying mechanisms have not been fully elucidated.
METHODS
Herein, we examined the expression of LDH and COX4 by qRT-PCR, western blot, immunohistochemistry and immunofluorescence. We detected metabolites of lactic acid and reactive oxygen species for functional tests. We used tetramethylrhodamine methyl ester (TMRM) staining and a transmission electron microscope to clarify the mitochondrial status. After using western blot and immunofluorescence to clarify the change of DRP1, we further examined MFF, PINK1, and PARKIN by western blot. We used cyclosporin A (CsA) to confirm the regulation of mitophagy and ceased the stretching as a rescue experiment.
RESULTS
Herein, we ascertained that mechanical force could increase the level of LDH and decrease the expression of COX4 in PDLSCs. Simultaneously, the yield of reactive oxygen species (ROS) in PDLSC reduced after stretching, while lactate acid augmented significantly. Furthermore, mitochondrial function in PDLSCs was negatively affected by impaired mitochondrial membrane potential (MMP) under mechanical force, and the augment of mitochondrial fission further induced PRKN-dependent mitophagy, which was confirmed by the rescue experiments via blocking mitophagy. As a reversible physiological stimulation, the anaerobic preference of PDLSCs altered by mechanical force could restore after the cessation of force stimulation.
CONCLUSIONS
Altogether, our study demonstrates that PDLSCs under mechanical force preferred anaerobic oxidation induced by the affected mitochondrial dynamics, especially mitophagy. Our findings support an association between mechanical stimulation and the oxidative profile of stem cells, which may shed light on the mechanical guidance of stem cell maintenance and commitment, and lay a molecular foundation for periodontal tissue regeneration.
Topics: Periodontal Ligament; Anaerobiosis; Mitophagy; Reactive Oxygen Species; Oxidation-Reduction
PubMed: 37480044
DOI: 10.1186/s11658-023-00453-w -
Bioresource Technology Jan 2022Mixed anaerobic microbial communities are a key component in valorization of waste biomass via anaerobic digestion. Similar microbial communities are important as soil... (Review)
Review
Mixed anaerobic microbial communities are a key component in valorization of waste biomass via anaerobic digestion. Similar microbial communities are important as soil and animal microbiomes and have played a critical role in shaping the planet as it is today. Understanding how individual species within communities interact with others and their environment is important for improving performance and potential applications of an inherently green technology. Here, the challenges associated with making measurements critical to assessing the status of anaerobic microbial communities are considered. How these measurements could be incorporated into control philosophies and augment the potential of anaerobic microbial communities to produce different and higher value products from waste materials are discussed. The benefits and pitfalls of current genetic and molecular approaches to measuring and manipulating anaerobic microbial communities and the challenges which should be addressed to realise the potential of this exciting technology are explored.
Topics: Anaerobiosis; Animals; Biomass; Bioreactors; Microbiota
PubMed: 34780902
DOI: 10.1016/j.biortech.2021.126326 -
Molecular Biology and Evolution May 2021The transition of free-living organisms to parasitic organisms is a mysterious process that occurs in all major eukaryotic lineages. Parasites display seemingly unique... (Comparative Study)
Comparative Study
The transition of free-living organisms to parasitic organisms is a mysterious process that occurs in all major eukaryotic lineages. Parasites display seemingly unique features associated with their pathogenicity; however, it is important to distinguish ancestral preconditions to parasitism from truly new parasite-specific functions. Here, we sequenced the genome and transcriptome of anaerobic free-living Mastigamoeba balamuthi and performed phylogenomic analysis of four related members of the Archamoebae, including Entamoeba histolytica, an important intestinal pathogen of humans. We aimed to trace gene histories throughout the adaptation of the aerobic ancestor of Archamoebae to anaerobiosis and throughout the transition from a free-living to a parasitic lifestyle. These events were associated with massive gene losses that, in parasitic lineages, resulted in a reduction in structural features, complete losses of some metabolic pathways, and a reduction in metabolic complexity. By reconstructing the features of the common ancestor of Archamoebae, we estimated preconditions for the evolution of parasitism in this lineage. The ancestor could apparently form chitinous cysts, possessed proteolytic enzyme machinery, compartmentalized the sulfate activation pathway in mitochondrion-related organelles, and possessed the components for anaerobic energy metabolism. After the split of Entamoebidae, this lineage gained genes encoding surface membrane proteins that are involved in host-parasite interactions. In contrast, gene gains identified in the M. balamuthi lineage were predominantly associated with polysaccharide catabolic processes. A phylogenetic analysis of acquired genes suggested an essential role of lateral gene transfer in parasite evolution (Entamoeba) and in adaptation to anaerobic aquatic sediments (Mastigamoeba).
Topics: Adaptation, Biological; Anaerobiosis; Animals; Archamoebae; Biological Evolution; Entamoeba histolytica; Gene Transfer, Horizontal; Genome Size; Genome, Protozoan; Parasites; Transcriptome
PubMed: 33528570
DOI: 10.1093/molbev/msab020 -
Current Opinion in Microbiology Dec 2021Microbial consortia efficiently degrade complex biopolymers found in the organic fraction of municipal solid waste (OFMSW). Through enzyme production and division of... (Review)
Review
Microbial consortia efficiently degrade complex biopolymers found in the organic fraction of municipal solid waste (OFMSW). Through enzyme production and division of labor during anaerobic digestion, microbial communities break down recalcitrant polymers and make fermentation products, including methane. However, microbial communities remain underutilized for waste degradation as it remains difficult to characterize and predict microbial interactions during waste breakdown, especially as cultivation conditions change drastically throughout anaerobic digestion. This review discusses recent progress and opportunities in cultivating natural and engineered consortia for OFMSW hydrolysis, including how recalcitrant substrates are degraded by enzymes as well as the critical factors that govern microbial interactions and culture stability. Methods to measure substrate degradation are also reviewed, and we demonstrate the need for increased standardization to enable comparisons across different environments.
Topics: Anaerobiosis; Bioreactors; Microbiota; Polymers; Refuse Disposal
PubMed: 34700124
DOI: 10.1016/j.mib.2021.09.008 -
Waste Management (New York, N.Y.) Mar 2022Digestate is a nutrient-rich by-product from organic waste anaerobic digestion but can contribute to nutrient pollution without comprehensive management strategies. Some... (Review)
Review
Digestate is a nutrient-rich by-product from organic waste anaerobic digestion but can contribute to nutrient pollution without comprehensive management strategies. Some nutrient pollution impacts include harmful algal blooms, hypoxia, and eutrophication. This contribution explores current productive uses of digestate by analyzing its feedstocks, processing technologies, economics, product quality, impurities, incentive policies, and regulations. The analyzed studies found that feedstock, processing technology, and process operating conditions highly influence the digestate product characteristics. Also, incentive policies and regulations for managing organic waste by anaerobic digestion and producing digestate as a valuable product promote economic benefits. However, there are not many governmental and industry-led quality assurance certification systems for supporting commercializing digestate products. The sustainable and safe use of digestate in different applications needs further development of technologies and processes. Also, incentives for digestate use, quality regulation, and social awareness are essential to promote digestate product commercialization as part of the organic waste circular economy paradigm. Therefore, future studies about circular business models and standardized international regulations for digestate products are needed.
Topics: Anaerobiosis; Environment; Eutrophication
PubMed: 35032793
DOI: 10.1016/j.wasman.2021.12.035 -
Bulletin of Mathematical Biology Nov 2021A multiscale mathematical model is presented to describe de novo granulation, and the evolution of multispecies granular biofilms, in a continuously fed bioreactor. The...
A multiscale mathematical model is presented to describe de novo granulation, and the evolution of multispecies granular biofilms, in a continuously fed bioreactor. The granule is modelled as a spherical free boundary domain with radial symmetry. The equation governing the free boundary is derived from global mass balance considerations and takes into account the growth of sessile biomass as well as exchange fluxes with the bulk liquid. Starting from a vanishing initial value, the expansion of the free boundary is initiated by the attachment process, which depends on the microbial species concentrations within the bulk liquid and their specific attachment velocity. Nonlinear hyperbolic PDEs model the growth of the sessile microbial species, while quasi-linear parabolic PDEs govern the dynamics of substrates and invading species within the granular biofilm. Nonlinear ODEs govern the evolution of soluble substrates and planktonic biomass within the bulk liquid. The model is applied to an anaerobic, granular-based bioreactor system, and solved numerically to test its qualitative behaviour and explore the main aspects of de novo anaerobic granulation: ecology, biomass distribution, relative abundance, dimensional evolution of the granules and soluble substrates, and planktonic biomass dynamics within the bioreactor. The numerical results confirm that the model accurately describes the ecology and the concentrically layered structure of anaerobic granules observed experimentally, and that it can predict the effects on the process of significant factors, such as influent wastewater composition; granulation properties of planktonic biomass; biomass density; detachment intensity; and number of granules.
Topics: Anaerobiosis; Biofilms; Biomass; Bioreactors; Mathematical Concepts; Models, Biological
PubMed: 34741191
DOI: 10.1007/s11538-021-00951-y -
Bioengineered Jan 2022Animal manure is the main source of bioenergy production by anaerobic digestion (AD). However, the pathogenic bacteria in manure may pose a high risk to human health by... (Review)
Review
Animal manure is the main source of bioenergy production by anaerobic digestion (AD). However, the pathogenic bacteria in manure may pose a high risk to human health by contaminating the environment if not effectively inactivated during AD. Worldwide, more than 20,000 biogas plants are running for the treatment of animal manure. AD has been playing the important role in establishing a circular economy in the agricultural sector and may contribute to the United Nations sustainable development goal (UN SDG). Nevertheless, whether AD is a reliable approach for pathogens inactivation has been challenged. A comprehensive understanding of the coping mechanisms of pathogens with adverse conditions and the challenges of establishing the AD process to inactivate effectively pathogens are yet to be analyzed. In this review, the diversity and resistance of pathogens in animal manure are summarized. The efficiencies and the difficulties of their inactivations in AD are also analyzed. In particular, three forms of pathogens i.e. sporing-forming pathogens, viable but non-culturable (VBNC) pathogens, and persistent pathogens are discussed. The factors influencing the pathogens' inactivation and AD efficiencies are analyzed. The trade-off between energy production and pathogens inactivation in an AD system was consequently pointed out. This review concluded that the development of anaerobic processes should meet the goals of high efficient bioenergy production and deep hygienization.
Topics: Agriculture; Anaerobiosis; Animals; Biofuels; Bioreactors; Manure
PubMed: 35258411
DOI: 10.1080/21655979.2021.2017717