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

Bacillus thuringiensis: fermentation process and risk assessment: a short review

Several factors make the local production of Bacillus thuringiensis (Bt) highly appropriate for pest control in developing nations. Bt can be cheaply produced on a wide variety of low cost, organic substrates. Local production results in considerable savings in hard currency which otherwise would be spent on importation of chemical and biological insecticides. The use of Bt in Brazil has been limited in comparison with chemical insecticides. Although Bt is imported, some Brazilian researchers have been working on its development and production. Fermentation processes (submerged and semi-solid) were applied, using by-products from agro-industries. As the semi-solid fermentation process demonstrated to be interesting for Bt endotoxins production, it could be adopted for small scale local production. Although promising results had been achieved, national products have not been registered due to the absence of a specific legislation for biological products. Effective actions are being developed in order to solve this gap. Regardless of the biocontrol agents being considered atoxic and harmless to the environment, information related to direct and indirect effects of microbials are still insufficient in many cases. The risk analysis of the use of microbial control agents is of upmost importance nowadays, and is also discussed.

The effects of added glycerol or unprotected free fatty acids or a combination of the two on silage intake, milk production, rumen fermentation and diet digestibility in cows given grass silage based diets

Selostus: Väkirehuun lisätyn glyserolin tai vapaiden rasvahappojen tai näiden yhdistelmän vaikutus maidontuotantoon ja pötsifermentaatioon ruokittaessa lypsylehmiä säilörehuun perustuvalla ruokinnalla

Effects of and interactions between the extent of silage fermentation and protein and protein supplementation in lactating dairy cows

Selostus: Säilörehun käymisasteen ja valkuaistäydennyksen vaikutus maidon tuotantoon

Production of Acetic Acid by Fermentation with Propionibacteria, HR-321, 1993

This project was undertaken jointly with a project supported by the Iowa Corn Promotion Board. Together the projects aimed at producing the organic acids, propionic acid and acetic acid, by fermentation. The impacts were to provide agriculturally-based alternatives to production of these acids, currently produced mainly as petrochemicals. The potentially high-demand use for acetic acid is as the "acetate" in Calcium Magnesium Acetate (CMA), the non-corrosive road deicer. Fermentation was, however, far from being an economically acceptable alternative. Gains were made in this work toward making this a feasible route. These advances included (1) development of a variant strain of propionibacteria capable of producing higher concentrations of acids; (2) comparison of conditions for several ways of cultivating free cells and establishment of the relative benefits of each; (3) achievement of the highest productivity in fermentations using immobilized cells; (4) identification of corn steep liquor as a lower cost substrate for the fermentation; (5) application of a membrane extraction system for acid recovery and reduction of product inhibition; and (6) initial use of more detailed economic analysis of process alternatives to guide in the identification of where the greatest payback potential is for future research. At this point, the fermentation route to these acids using the propionibacteria is technically feasible, but economically unfeasible. Future work with integration of the above process improvements can be expected to lead to further gains in economics. However, such work can not be expected to make CMA a less expensive deicer than common road salt.

Efeito de métodos de coleta de fluido ruminal em bovinos sobre alguns parâmetros ruminais e microbiológicos

Estudou-se o efeito de três métodos de coleta (manual, bomba a vácuo e sonda nasoesofageana) sobre os teores de ácidos graxos voláteis totais (AGVt), nitrogênio amoniacal e número de protozoários no fluido ruminal de bovino. Utilizou-se o delineamento inteiramente casualizado, com três tratamentos e cinco repetições. Os resultados revelaram que o método da sonda nasoesofageana proporcionou valores menores dos ácidos propiônico, butírico, AGVt e de nitrogênio amoniacal no fluido ruminal. O número total de protozoários não foi afetado pelos métodos de coleta de conteúdo ruminal. O método de coleta manual e por meio de bomba a vácuo mostraram-se eficientes para os parâmetros estudados.

Degradabilidad ruminal del forraje disponible en la pradera y del aparentemente consumido por vacas lecheras

Se evaluó la dinámica degradativa de forrajes, en muestras de una pradera permanente (Lolium perenne L.), manejadas a dos alturas de pradera, alta y baja. Las muestras consistieron en forraje disponible a ras de suelo (FD) y en forraje aparentemente consumido por vacas lecheras en pastoreo continuo (FS). La degradabilidad ruminal se estudió usando la técnica de las bolsas de dacrón y los datos fueron ajustados a una ecuación exponencial. La fracción soluble (g/kg MS), de la materia seca (MS) (299 v/s 351, s.e.d.= 5,4), de la materia organica (MO) (304 v/s 376, s.e.d.= 3,3) y del nitrógeno (250 v/s 301, s.e.d.= 6,4), fueron significativamente mayores (P<0,05) en muestras de FS que en muestras de FD. La degradabilidad potencial (g/kg MS) de MS, MO y nitrógeno, fue significativamente mayor (P<0,05) en las muestras de FS, que en las muestras de FD. La degradabilidad efectiva fue mayor en las muestras de FS, que en las muestras de FD, tanto para la MS (474 v/s 508, s.e.d.= 13,0), MO (490 v/s 529, s.e.d.= 11,6) y nitrógeno (351 v/s 419, s.e.d.= 10,0). Respecto del factor altura, sólo se encontró un efecto significativo en la degradabilidad efectiva en el nitrógeno, en favor de la altura baja (365 v/s 406, s.e.d.= 10,0).