Feasibility study of an alkaline-based chemical treatment for the purification of polyhydroxybutyrate produced by a mixed enriched culture

This study focused on investigating the feasibility of purifying polyhydroxybutyrate (PHB) from mixed culture biomass by alkaline-based chemical treatment. The PHB-containing biomass was enriched on acetate under non-sterile conditions. Alkaline treatment (0.2 M NaOH) together with surfactant SDS (0.2 w/v% SDS) could reach 99% purity, with more...

Exact derivation of the geometric correction factor of the center notched test specimen, based on small cracks merging as explanation of softening

The exact derivation of the mode I geometric correction factor is given, based on the small crack merging mechanism to show that this always is the real fracture mechanism in wood. This mechanism dominates at late softening and explains fully the apparent decrease of the energy release rate of macrocrack extension as already known for mode I and...

Functional characterization of a Penicillium chrysogenum mutanase gene induced upon co-cultivation with Bacillus subtilis

Background Microbial gene expression is strongly influenced by environmental growth conditions. Comparison of gene expression under different conditions is frequently used for functional analysis and to unravel regulatory networks, however, gene expression responses to co-cultivation with other microorganisms, a common occurrence in nature, is...