Paper mill effluent (PME) was used as an organic feedstock for production of biohydrogen via dark fermentation using heat-shock pretreated anaerobic sludge under mesophilic conditions. The influence of substrate concentration (5, 10 and 15 g-COD/L) and the initial pH (5 and 7) on the efficiency of dark hydrogen fermentation from PME were investigated. The highest hydrogen yield of 55.4 mL/g-COD...

BACKGROUND Theabrownins (TB) are bioactive components that are usually extracted from Chinese dark tea, in which they are present at low concentrations. The present study aimed to produce an instant dark tea high in theabrownins via submerged fermentation by the fungus Aspergillus niger. Three fermentation parameters that affect theabrownins content (i.e. inoculum size, liquid-solid ratio and r...

The depletion of fossil fuel diverts us to the use of renewable resources as the supplement for fuel. Solar, hydroelectric power and microbial system are known to be abundant renewable resources for fuel production. Hydrogen has a energy yield of 122 kJ/g, which is 2.75 times greater than hydrocarbon fuels (Kapdan & Kargi, 2006). Hydrogen together with oxygen is the key element in the biologica...

Biohydrogen production by dark fermentation of different waste materials is a promising approach to produce bio-energy in terms of renewable energy exploration. This communication has reviewed various influencing factors of dark fermentation process with detailed account of determinants in biohydrogen production. It has also focused on different factors such as improved bacterial strain, reacto...

Under anaerobic conditions, in the dark and in the absence of electron acceptors, organic compounds are catabolized by strictly anaerobic or facultatively anaerobic bacteria by internally balanced oxidation–reduction reactions, a process called fermentation. In fermentation, the organic compound serves as both electron donor and acceptor, and adenosine triphosphate is synthesized by substrate l...

Permeable sediments are common across continental shelves and are critical contributors to marine biogeochemical cycling. Organic matter in permeable sediments is dominated by microalgae, which as eukaryotes have different anaerobic metabolic pathways to prokaryotes such as bacteria and archaea. Here we present analyses of flow-through reactor experiments showing that dissolved inorganic carbon...

Proof of principle of biohythane and potential energy production from garden waste (GW) is demonstrated in this study in a two-step process coupling dark fermentation and anaerobic digestion. The synergistic effect of using co-cultures of extreme thermophiles to intensify biohydrogen dark fermentation is demonstrated using xylose, cellobiose and GW. Co-culture of Caldicellulosiruptor saccharoly...

Using dark fermentation, hydrogen can be generated from renewable organics including waste materials. Key to successful application of anaerobic fermentation is to uncouple liquid and biomass retention times in reactor system. This paper reviews reactor configurations (fixed-bed, fluidized-bed, upflow anaerobic sludge blanket and continuous stirred tank reactors) and operating processes (batch,...

Chlamydomonas reinhardtii, a unicellular green alga, often experiences hypoxic/anoxic soil conditions that activate fermentation metabolism. We isolated three Chlamydomonas mutants disrupted for the pyruvate formate lyase (PFL1) gene; the encoded PFL1 protein catalyzes a major fermentative pathway in wild-type Chlamydomonas cells. When the pfl1 mutants were subjected to dark fermentative condit...