we introduce a new smooth, non-toxic, biocompatible method for cross-linking of gum tragacanth (gt), a polysaccharide of natural origin, in order to serve as a new supporting matrix for immobilization systems.  the modified gum is used as a matrix for the catalysis of the conversion of benzyl penicillin to 6-aminopenicillanic acid (6-apa) by means of escherichia coli atcc11105 with penicillin g...

Techniques of immobilization of microbial- cells have been established by multifunctional reagents such as glutaraldehyed on a solid support. Immobilized cell reactor was designed to demonstrate stability of cross linking of whole cells for the production of organic acids. An eighty-six percent conversion of glucose was obtained for an eight hour retention time. The immobilized cell reacto...

Whole cells of Bacillus sp., bacitracin-producing bacteria, were immobilized in polyacrylamide gel prepared by using 5% total acrylamide (95% acrylamide monomer and 5% N, N'-methylenebis acrylamide). Bacitracin production by the immobilized whole cells was examined by using various fermentation media. In starch-bouillon medium, the initial activity of immobilized whole cells for bacitracin prod...

background and objectives : the attempts were made to describe the development of a whole cell immobilization of p. pastoris by entrapping the cells in polyacrylamide gel beads. the alcohol oxidase activity of the whole cell pichia pastoris was evaluated in comparison with yeast biomass production. materials and methods : methylotrophic yeast p. pastoris was obtained from collection of standard...

Biodiesel is an attractive alternative fuel because of its nontoxicity and biodegradability properties. Biodiesel is produced through transesterification of vegetable oils’ triglyceride. It is obtained from vegetable oils or fats either by chemical or enzyme-catalyzed transesterification with methanol or ethanol. By using whole-cell biocatalyst immobilized within biomass support particles (BSPs...

Rhodococcus has diverse metabolic capabilities, such as delaying ripening of certain climacteric fruit. Nitrile hydratase (NHase), amidase, 1-aminocyclopropane-1-carboxylate deaminase (ACC deaminase), cyanidase, and β-cyanoalanine synthase-like enzyme (βCAS-like) are possibly involved in fruit ripening. The activity of these enzymes in Rhodococcus rhodochrous DAP 96253 cells were induced with s...

BACKGROUND Whole-cell biocatalysis in organic solvents has been widely applied to industrial bioprocesses. In two-phase water-solvent processes, substrate conversion yields and volumetric productivities can be limited by the toxicity of solvents to host cells and by the low mass transfer rates of the substrates from the solvent phase to the whole-cell biocatalysts in water. RESULTS To solve t...

The fermentation of Streptomyces griseus for the production of cycloheximide is similar to other antibiotic fermentations in that product synthesis is subject to feedback regulation and the desired product is degraded in the fermentation broth. The productivity of this fermentation can thus be dramatically increased by removing the antibiotic from the whole broth as it is produced. One means fo...

The aim of this work was to study the physiological changes of immobilized brewing yeast Saccharomyces cerevisiae in a continuous reactor. Continuous cultivation was carried out at three different temperatures (15, 20 and 25°C) with an industrial brewing yeast strain (UNICER, Bebidas de Portugal, S.A.). During the continuous experiment the viability of free and immobilized cells was followed us...