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- Acidogeneze je proces enzymatické přeměny organických sloučenin na organické kyseliny. Je to zároveň druhá fáze anaerobního kvašení. Do acidogeneze se zapojují bakterie jako . Acidogen je mikroorganizmus aktivní při acidogenezi. (cs)
- Die Acidogenese stellt neben der Hydrolyse, der Acetogenese und der Methanogenese einen Schritt der Gärung in einem fakultativ anaeroben Abbauprozess dar. Sie läuft gleichzeitig mit der Hydrolyse ab, und bei dieser unspezifischen Säurebildung werden die monomeren Interdukte der Hydrolyse einerseits in niedere Fett-/Carbonsäuren, wie z. B. Butter-, Propion- und Essigsäure, andererseits in niedere Alkohole, wie z. B. Ethanol, umgesetzt. Bei diesem Umsetzungsschritt verzeichnen die fakultativ anaeroben Mikroorganismen erstmals einen Energiegewinn und es werden bei dieser Umsetzung bereits bis zu 20 % des Gesamtanteils an Essigsäure gebildet. (de)
- Acidogenesis is the second stage in the four stages of anaerobic digestion:
* Hydrolysis: A chemical reaction where particulates are solubilized and large polymers converted into simpler monomers;
* Acidogenesis: A biological reaction where simple monomers are converted into volatile fatty acids;
* Acetogenesis: A biological reaction where volatile fatty acids are converted into acetic acid, carbon dioxide, and hydrogen
* Methanogenesis: A biological reaction where acetates are converted into methane and carbon dioxide, while hydrogen is consumed. Anaerobic digestion is a complex biochemical process of biologically mediated reactions by a consortium of microorganisms to convert organic compounds into methane and carbon dioxide. It is a stabilization process, reducing odor, pathogens, and mass reduction. Hydrolytic bacteria form a variety of reduced end-products from the fermentation of a given substrate. One fundamental question that arises concerns the metabolic features that control carbon and electron flow to a given reduced end-product during pure culture and mixed methanogenic cultures of hydrolytic bacteria. Thermoanaerobium brockii is a representative thermophilic, hydrolytic bacterium, which ferments glucose, via the Embden–Meyerhof Parnas Pathway. T. brockii is an atypical hetero-lactic acid bacterium because it forms molecular hydrogen (H2), in addition to lactic acid and ethanol. The reduced end-products of glucose fermentation are enzymatically formed from pyruvate, via the following mechanisms: lactate by fructose 1-6 all-phosphate (F6P) activated lactate dehydrogenase; H2 by pyruvate ferredoxin oxidoreductase and hydrogenase; and ethanol via NADH- and NADPH-linked alcohol dehydrogenase. By its side, the acidogenic activity was found in the early 20th century, but it was not until the mid-1960s that the engineering of phases separation was assumed in order to improve the stability and waste digesters treatment. In this phase, complex molecules (carbohydrates, lipids, and proteins) are depolymerized into soluble compounds by hydrolytic enzymes (cellulases, hemicellulases, amylases, lipases and proteases). The hydrolyzed compounds are fermented into volatile fatty acids (acetate, propionate, butyrate, and lactate), neutral compounds (ethanol, methanol), ammonia, hydrogen and carbon dioxide. Acetogenesis is one of the main reactions of this stage, in this, the intermediary metabolites produced are metabolized to acetate, hydrogen and carbonic gas by the three main groups of bacteria:
* ;
* ; and
* . For the acetic acid production are considered three kind of bacteria:
* Clostridium aceticum;
* ; and
* . Winter y Wolfe, in 1979, demonstrated that A. woodii in syntrophic association with Methanosarcina produce methane and carbon dioxide from fructose, instead of three molecules of acetate. Moorella thermoacetica and are able to reduce the carbonic gas to acetate, but they do not have hydrogenases which inhabilite the hydrogen use, so they can produce three molecules of acetate from fructose. Acetic acid is equally a co-metabolite of the organic substrates fermentation (sugars, glycerol, lactic acid, etc.) by diverse groups of microorganisms which produce different acids:
* Propionic bacteria (propionate + acetate);
* Clostridium (butyrate + acetate);
* Enterobacteria (acetate + lactate); and
* Hetero-fermentative bacteria (acetate, propionate, butyrate, valerate, etc.). (en)
- L'acidogenèse est un type de digestion. C'est l'un des plus rapides dans le type anaérobie. Durant l'acidogénèse, les acides aminés, les sucres et les graisses sont transformés en acides organiques. Des bactéries dites acidogènes produisent des alcools et des acides organiques, ainsi que de l'hydrogène et du dioxyde de carbone. Ces bactéries appartiennent souvent au genre Clostridium, mais certaines font partie des genres Bacteroides, Bacillus, , , ou de la famille des Enterobacteriaceae. Durant le procédé biologique de méthanisation, l'acidogenèse est la deuxième étape sur quatre, et la plus rapide. En présence d'une grande quantité de matière organique, elle peut produire trop d'acides qui ralentissent, voire empêchent, les réactions suivantes. (fr)
- Las diferentes especies bacterianas que son capaces de realizar la acetogénesis se denominan colectivamente acetógenos. La digestión anaerobia también denominada biometanización, es un proceso microbiológico en el cual la materia biodegradable se descompone en ausencia de oxígeno mediante la acción de distintos grupos de bacterias, dando como resultado dos productos principales: biogás y digestato. (es)
- A acidogênese consiste na capacidade de produção de ácidos a partir da fermentação de carboidratos. Diversos microrganismos comensais ou patogênicos são capazes de produzir ácidos a partir da fermentação de açúcares. O que é Acidogênese?Durante Acidogênese na Biodigestão Anaeróbia, os produtos hidrolisados são metabolizados no interior das bactérias em álcoois (etanol), cetonas, (acetona), aldeídos, hidrogênio, dióxido de carbono e principalmente ácidos orgânicos (ácido acético, propanóico, ácido butanóico, ácido láctico). Além disso, durante o processo são geradas novas células bacterianas. A pressão parcial do hidrogênio é um fator determinante para os tipos de produtos a serem gerados durante a acidogênese, quanto maior a pressão parcial, menor a quantidade de ácido acético e hidrogênio formados em favorecimento da geração de ácidos orgânicos de cadeia longa. (SCHERER 1995). FontesB. Machado 2016: Bezerra Machado, Gleysson; Geração e Aproveitamento Energético do Biogás, PROJETO PROBIOGÁS 2016SCHERER P.A. 1995: Vergärung. In: Thomé-Kozmiensky, K.J. (Hrsg.): Biologische Abfallbehandlung – Enzyklopädie der Kreislaufwirtschaft. Berlin : EF-Verlag für Energie- und Umwelttechnik, 1995, S. 359–372. (pt)
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| rdfs:comment
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- Acidogeneze je proces enzymatické přeměny organických sloučenin na organické kyseliny. Je to zároveň druhá fáze anaerobního kvašení. Do acidogeneze se zapojují bakterie jako . Acidogen je mikroorganizmus aktivní při acidogenezi. (cs)
- Die Acidogenese stellt neben der Hydrolyse, der Acetogenese und der Methanogenese einen Schritt der Gärung in einem fakultativ anaeroben Abbauprozess dar. Sie läuft gleichzeitig mit der Hydrolyse ab, und bei dieser unspezifischen Säurebildung werden die monomeren Interdukte der Hydrolyse einerseits in niedere Fett-/Carbonsäuren, wie z. B. Butter-, Propion- und Essigsäure, andererseits in niedere Alkohole, wie z. B. Ethanol, umgesetzt. Bei diesem Umsetzungsschritt verzeichnen die fakultativ anaeroben Mikroorganismen erstmals einen Energiegewinn und es werden bei dieser Umsetzung bereits bis zu 20 % des Gesamtanteils an Essigsäure gebildet. (de)
- Las diferentes especies bacterianas que son capaces de realizar la acetogénesis se denominan colectivamente acetógenos. La digestión anaerobia también denominada biometanización, es un proceso microbiológico en el cual la materia biodegradable se descompone en ausencia de oxígeno mediante la acción de distintos grupos de bacterias, dando como resultado dos productos principales: biogás y digestato. (es)
- Acidogenesis is the second stage in the four stages of anaerobic digestion:
* Hydrolysis: A chemical reaction where particulates are solubilized and large polymers converted into simpler monomers;
* Acidogenesis: A biological reaction where simple monomers are converted into volatile fatty acids;
* Acetogenesis: A biological reaction where volatile fatty acids are converted into acetic acid, carbon dioxide, and hydrogen
* Methanogenesis: A biological reaction where acetates are converted into methane and carbon dioxide, while hydrogen is consumed.
* ;
* ; and
* . (en)
- L'acidogenèse est un type de digestion. C'est l'un des plus rapides dans le type anaérobie. Durant l'acidogénèse, les acides aminés, les sucres et les graisses sont transformés en acides organiques. Des bactéries dites acidogènes produisent des alcools et des acides organiques, ainsi que de l'hydrogène et du dioxyde de carbone. Ces bactéries appartiennent souvent au genre Clostridium, mais certaines font partie des genres Bacteroides, Bacillus, , , ou de la famille des Enterobacteriaceae. (fr)
- A acidogênese consiste na capacidade de produção de ácidos a partir da fermentação de carboidratos. Diversos microrganismos comensais ou patogênicos são capazes de produzir ácidos a partir da fermentação de açúcares. O que é Acidogênese?Durante Acidogênese na Biodigestão Anaeróbia, os produtos hidrolisados são metabolizados no interior das bactérias em álcoois (etanol), cetonas, (acetona), aldeídos, hidrogênio, dióxido de carbono e principalmente ácidos orgânicos (ácido acético, propanóico, ácido butanóico, ácido láctico). Além disso, durante o processo são geradas novas células bacterianas. (pt)
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