Pathways and bioenergetics of anaerobic carbon monoxide fermentation

Carbon monoxide can act as a substrate for different modes of fermentative anaerobic metabolism. The trait of utilizing CO is spread among a diverse group of microorganisms, including members of bacteria as well as archaea. Over the last decade this metabolism has gained interest due to the potential of converting CO-rich gas, such as synthesis gas, into bio-based products. Three main types of fermentative CO metabolism can be distinguished: hydrogenogenesis, methanogenesis, and acetogenesis, generating hydrogen, methane and acetate, respectively. Here, we review the current knowledge on these three variants of microbial CO metabolism with an emphasis on the potential enzymatic routes and bio-energetics involved.

Postharvest shelf life extension of blueberries using a chitosan-based edible coating containing aloe vera juice

Poster

Optimization of low-cost nutritional supplementation for lignocellulosic ethanol fermentation

[Excerpt] Bioethanol from lignocellulosic materials (LCM), also called second generation bioethanol, is considered a promising alternative to first generation bioethanol. An efficient production process of lignocellulosic bioethanol involves an effective pretreatment of LCM to improve the accessibility of cellulose and thus enhance the enzymatic saccharification. One interesting approach is to use the whole slurry from treatment, since allows economical and industrial benefits: washing steps are avoided, water consumption is lower and the sugars from liquid phase can be used, increasing ethanol concentration [1]. However, during the pretreatment step some compounds (such as furans, phenolic compounds and weak acids) are produced. These compounds have an inhibitory effect on the microorganisms used for hydrolysate fermentation [2]. To overcome this, the use of a robust industrial strain together with agro-industrial by-products as nutritional supplementation was proposed to increase the ethanol productivities and yields. (...)

By-products of beer fermentation

Among the most important factors influencing beer quality is the presence of well-adjusted amounts of higher alcohols and esters; as well as the successful reduction of undesirable by-products such as diacetyl. While higher alcohols and esters contribute rather positively to the beer aroma, diacetyl is mostly unwelcome for beer types with lighter taste. Thus, the complex metabolic pathways in yeast responsible for the synthesis of both pleasant and unpleasant by-products of fermentation were given special attention in this last chapter.

Microbial production of potent phenolic-antioxidants through solid state fermentation

The agroindustrial residues including plant tissues rich in polyphenols were explored for microbial production of potent phenolics under solid state fermentation processes. The fungal strains capable of hydrolyzing tannin-rich materials were isolated from Mexican semidesert zones. These microorganisms have been employed to release potent phenolic antioxidants during the solid state fermentation of different materials (pomegranate peels, pecan nut shells, creosote bush and tar bush). This chapter includes the critical parameters for antioxidants production from selective microbes. Technical aspects of the microbial fermentation of antioxidants have also been discussed.

Effects of fermentation residues on the melt processability and thermomechanical degradation of PHBV produced from cheese whey using mixed microbial cultures

"Available online 28 March 2016"

Olive pomace pretreatments to enhance its valorisation by solid-state fermentation

Dissertação de mestrado em Bioengenharia

Production of biohydrogen from dark fermentation of organic wastes

Dissertação de mestrado em Bioengenharia

Malolactic fermentation in winemaking: evaluation of operational parameters

Dissertação de mestrado em Bioengenharia