Showing papers by "Patrizia Brigidi published in 1993"

Fermentative production of l -lactic acid by Lactobacillus casei DSM 20011 and product recovery using ion exchange resins

Abstract: In order to produce l(+)-lactic acid to be employed in poly-l-lactic acid polymer production, for biomedical applications, the strain Lactobacillus casei subsp. casei DSM 20011 was studied in a conventional batch mode using different initial concentrations of glucose. The results obtained showed that the initial glucose concentration exerts an influence on the fermentation pattern, modifying the different fermentation parameters. Nevertheless, the product yield remained at a constant value of 0.86 g·g−1. The proposed novel system of product recovery, based on the use of ion-exchange resins, gave high yields of pure lactic acid.

Cloning of the gene for cholesterol oxidase in Bacillus spp., Lactobacillus reuteri and its expression in Escherichia coli

Abstract: The cloning of the cholesterol oxidase gene in several Gram-positive bacteria, including Lactobacillus reuteri of intestinal origin, was obtained. Only the trans-formants of Escherichia coli harbouring the recombinant plasmid pCHOA showed a good intracellular enzyme activity. The heterologous gene was stably maintained in Gram-positive transformants but no enzyme activity was detected.