Acidogenesis

Acidogenesis
biological process (en)
Bayanai
Ƙaramin ɓangare na	short-chain fatty acid metabolic process (en) da fatty acid biosynthetic process (en)

Acidogenesis shine mataki na biyu a cikin matakai huɗu na narkewar anaerobic:

• Hydrolysis: Halin sinadarai inda aka solubilized da kuma manyan polymers canza zuwa sauki monomers;
• Acidogenesis: Halin halitta inda ake canza monomers masu sauƙi zuwa fatty acids masu narkewa;
• Acetogenesis: Halin halitta inda ake canza fatty acids zuwa acetic acid, carbon dioxide, da Hydrogen
• Methanogenesis: Halin halitta inda ake canza acetates zuwa methane da carbon dioxide, yayin da ake cinye hydrogen.

Anaerobic digestion wani tsari ne mai rikitarwa na kwayoyin halitta na halayen da aka yi amfani da su ta hanyar kwayoyin halitta don canza mahadi na kwayoyin cuta methane da carbon dioxide. Tsarin daidaitawa ne wanda ke rage ƙanshi, pathogens, da ƙarar sharar gida.

ƙwayoyin cuta na Hydrolytic suna samar da nau'ikan ƙananan samfurori daga fermentation na wani abu da aka ba su. Ɗaya daga cikin mahimman tambayoyin da ke tasowa ya shafi siffofin metabolism waɗanda ke sarrafa carbon da electron zuwa wani rageccen samfurin ƙarshe a lokacin al'adu mai tsabta da al'adun methanogenic na kwayoyin hydrolytic. Thermoanaerobium brockii wakiltar Thermophilic ne, kwayar cuta ta hydrolytic, wanda ke yisti glucose, ta hanyar Hanyar Embden-Meyerhof Parnas Pathway . T. Brockii kwayar cuta ce ta hetero-lactic acid saboda tana samar da hydrogen (H<sub id="mwMQ">2</sub>), ban da lactic acid da ethanol. Rage samfurori na ƙarshe na fermentation na glucose an kafa su ne daga pyruvate, ta hanyar hanyoyin da ke biyowa: lactate ta hanyar fructose 1-6 duk-phosphate (F6P) Hydrogenase" id="mwOA" rel="mw:WikiLink" title="Lactate dehydrogenase">lactate dehydrogenase; H2 ta hanyar pyruvate ferredoxin oxidoreductase da hydrogenase; da ethanol ta hanyar NADH- da NADPH-linked alcohol dehydrogenasa.

A gefensa, an sami aikin acidogenic a farkon karni na 20, amma ba har zuwa tsakiyar shekarun 1960 ba ne aka ɗauka aikin injiniya na rabuwa don inganta kwanciyar hankali da maganin magungunan sharar gida. A wannan matakin, kwayoyin rikitarwa (carbohydrates, lipids, da sunadarai) ana lalata su cikin mahaɗan da za a iya narkewa ta hanyar enzymes na hydrolytic (cellulases, hemicellulases, amylases, lipases da proteases). Ana narkar da mahaɗan hydrolyzed a cikin ƙwayoyin ƙwayoyin cuta (acetate, propionate, butyrate, da lactate), mahaɗan tsaka-tsaki (ethanol, methanol), ammoniya, hydrogen da carbon dioxide.^[1][2]

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:

• homoacetogens;
• syntrophes; and
• sulphoreductors.

Don samar da acid ana ɗaukar nau'ikan ƙwayoyin cuta guda uku:

• Clostridium aceticum;
• Acetobacter woodii; da kuma
• Clostridium termoautotrophicum.

Winter y Wolfe, a cikin 1979, ya nuna cewa A. woodii a cikin haɗin kai tare da Methanosarcin suna samar da methane da carbon dioxide daga fructose, maimakon kwayoyin acetate guda uku. Moorella thermoacetica da Clostridium formiaceticum suna iya rage iskar carbonic zuwa acetate, amma ba su da hydrogenes wanda ke hana amfani da hydrogen, don haka zasu iya samar da kwayoyin acetate guda uku daga fructose. Acetic acid daidai yake da co-metabolite na kwayoyin halitta fermentation (sukari, glycerol, lactic acid, da dai sauransu) ta kungiyoyi daban-daban na microorganisms waɗanda ke samar da acid daban-daban:

• Kwayoyin cuta na Propionic (propionate + acetate);
• Clostridium (butyrate + acetate);
• Enterobacteria (acetate + lactate); da kuma
• Kwayoyin cuta masu yisti (acetate, propionate, butyrate, valerate, da dai sauransu).

1. ↑ (in Spanish) Cairó, J.J. and París, J.M. (1988). Microbiología de la digestión anaerobia, metanogénesis. 4o Seminario de Depuración Anaerobia de Aguas Residuales. Valladolid. F.F. Polanco, P.A. García y S. Hernándo. (Eds.) pp. 41–51.
2. ↑ (in French) Laroche, M. (1983). Metabolisme intermediaire des acides gras volatils en fermentation methanique. These de Docteur – Ingenieur en Sciences Alimentaires_Fermentations. Institut National de la Recherche Agronomique, France.