Willibaldo Schmidell

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Monascus species can produce yellow, orange, and red pigments, depending on the employed cultivation conditions. They are classified as natural pigments and can be applied for coloration of meat, fishes, cheese, beer, and pates, besides their use in inks for printer and dyes for textile, cosmetic, and pharmaceutical industries. These natural pigments also(More)
It was the objective of the present study to increase the production of glucoamylase by Aspergillus awamori through solid state fermentation, using wheat bran as the main carbon source and (NH4)2SO4, urea, KH2PO4, glucose, maltose and starch as additional nitrogen, phosphorus, and carbon sources. The production of glucoamylase is strongly influenced by N(More)
Glucoamylase synthesis is strongly affected by yeast extract concentration (CE). An eight fold increase in CE caused a two fold increase in the maximum glucoamylase activity value (Am) for the cultivations conducted with an initial glucose concentration (GO) of about 20 g/l, and a four fold increase in Am in the runs with a Go value of about 40 g/l. Five(More)
Glucoamylase production kinetics was greatly affected by medium composition. While maltose and cassava flour induced glucoamylase synthesis, fructose clearly repressed it, reaching a maximum enzyne activity value (Am) of only 6% of those obtained with the former carbon sources. Among the nitrogen sources the best result was obtained with urea, reaching Am(More)
In batch mode, Klebsiella pneumoniae growth and 2,3-butanediol/acetoin formation are increasingly inhibited by initial sucrose concentrations (S0) over 60 g/L. At non inhibitory conditions, a maximum sucrose consumption rate of 1,5 g/L/h was measured. With S0=204 g/L however, this rate decreased to 0.15 g/L/h. K. pneumoniae fermented 204 g/L sucrose to(More)
This article gives an overview of high-cell-density cultures for polyhydroxyalkanoate (PHA) production and their modes of operation for increasing productivity. High cell densities are very important in PHA production mainly because this polymer is an intracellular product accumulated in various microorganisms, so a high cellular content is needed for the(More)
Among approaches applied to obtain high productivity and low production costs in bioprocesses are high cell density and the use of low cost substrates. Usually low cost substrates, as waste/agroindustrial residues, have low carbon concentration, which leads to a difficulty in operating bioprocesses. Real time control of process for intracellular products is(More)
Two kinds of mathematical correlations are proposed, one between the biomass concentration and the rheological parameter consistency index (K) from the 'Power law' and another between either the specific growth rate or the specific glucoamylase production rate and K. Experimental data from Aspergillus awamori batch cultivations, with initial polysaccharide(More)
Column experiments were utilized to investigate the effects of nitrate injection on sulfate-reducing bacteria (SRB) inhibition and microbial enhanced oil recovery (MEOR). An indigenous microbial consortium collected from the produced water of a Brazilian offshore field was used as inoculum. The presence of 150 mg/L volatile fatty acids (VFA´s) in the(More)
Pigments produced by species of Monascus have been used to coloring rice, meat, sauces, wines and beers in East Asian countries. Monascus can produce orange (precursor), yellow and red pigments. Orange pigments have low solubility in culture media and when react with amino groups they become red and largely soluble. The orange pigments are an alternative to(More)