Lipid production by robust Aspergillus oryzae BCC7051 and a mathematical model describing its growth and lipid phenotypic traits.

Aims: To identify the promising oleaginous Aspergillus oryzae strain and leverage its lipid and biomass production through a mathematical model.

Methods And Results: Comparative profiling of the cell growth and total fatty acid (TFA) content among 13 strains of A. oryzae was performed to explore the discrimination in their lipid productions.

Physiological Traits of Dihomo-γ-Linolenic Acid Production of the Engineered by Comparing Mathematical Models.

Dihomo-γ-linolenic acid (DGLA; C20:3 -6) is expected to dominate the functional ingredients market for its role in anti-inflammation and anti-proliferation. The DGLA production by the engineered strain of with overexpressing Δ-desaturase and Δ-elongase genes was investigated by manipulating the nutrient and fermentation regimes. Of the nitrogen sources tested, the maximum biomass and DGLA titers were obtained in the cultures using NaNO grown at pH 6.

Exploring differential traits of lipid-producing stages of the wild type and morphologically engineered strain of Aspergillus oryzae by comparative kinetic modeling.

Comparative profilings of cell growth and lipid production in the morphologically engineered strain (Δags1) and the wild type (WT) of Aspergillus oryzae BCC7051 were implemented. Using various nitrogen sources, a discrimination in cell morphology between the two strains was found, of which the Δags1 culture exhibited mycelial growth as small pellets in contrast to the WT. Of them, sodium nitrate and potassium nitrate were optimal for lipid production of the WT and Δags1 strains, respectively, which the highest lipid concentrations of 7.

Model of acetic acid-affected growth and poly(3-hydroxybutyrate) production by Cupriavidus necator DSM 545.

Acetic acid, a potential growth inhibitor, commonly occurs in lignocellulosic hydrolysates. The growth of Cupriavidus necator DSM 545 and production of poly(3-hydroxybutyrate) (PHB) by this bacterium in a glucose-based medium supplemented with various initial concentrations of acetic acid are reported. The bacterium could use both glucose and acetic acid to grow and produce PHB, but acetic acid inhibited growth once its initial concentration exceeded 0.

Furfural and glucose can enhance conversion of xylose to xylitol by Candida magnoliae TISTR 5663.

Xylitol production from xylose by the yeast Candida magnoliae TISTR 5663 was enhanced by supplementing the fermentation medium with furfural (300mg/L) and glucose (3g/L with an initial mass ratio of glucose to xylose of 1:10) together under oxygen limiting conditions. In the presence of furfural and glucose, the final concentration of xylitol was unaffected relative to control cultures but the xylitol yield on xylose increased by about 5%. Supplementation of the culture medium with glucose alone at an initial concentration of 3g/L, stimulated the volumetric and specific rates of xylose consumption and the rate of xylitol production from xylose.

Benzoate-induced stress enhances xylitol yield in aerobic fed-batch culture of Candida mogii TISTR 5892.

Production of the natural sweetener xylitol from xylose via the yeast Candida mogii TISTR 5892 was compared with and without the growth inhibitor sodium benzoate in the culture medium. Sodium benzoate proved to be an uncompetitive inhibitor in relatively poorly oxygenated shake flask aerobic cultures. In a better controlled aerobic environment of a bioreactor, the role of sodium benzoate could equally well be described as competitive, uncompetitive or noncompetitive inhibitor of growth.