Dextrans of Weissella cibaria DSM14295: Microbial production, structure and functionality.

Lactic acid bacteria of the genus Weissella contribute to spontaneous fermentation in, e.g., sourdough or sauerkraut, but are not registered as starter cultures because of their pending safety assessment.

Capsular Exopolysaccharides from Two Strains Differ in Their Moisture Sorption Behavior.

is a species frequently used in the manufacture of fermented milk. Apart from acid production, some strains additionally synthesize exopolysaccharides (EPS) which contribute to texture improvement and syneresis reduction, both being attributable to the EPS's high water binding capacity. There are two different types of EPS that may be produced, namely free exopolysaccharides (fEPS) which are secreted into the medium, and capsular EPS (cEPS) which remain attached to the bacterial cell wall.

Pilot scale isolation of exopolysaccharides from DGCC7710: Impact of methodical details on macromolecular properties and technofunctionality.

Exopolysaccharides (EPS) from provide similar technofunctionality such as water binding, viscosity enhancing and emulsifying effects as commercial thickeners at a significant lower concentration. Despite their high technofunctional potential, hetero polysaccharides from lactic acid bacteria are still not commercially used in unfermented foods, as the small amount of synthesised EPS calls for a high isolation effort. This study aims to analyse the macromolecular properties of EPS and cell containing isolates from DGCC7710 obtained by different isolation protocols, and to link these data to the technofunctionality in model food systems.

Degradation of Exopolysaccharides from Lactic Acid Bacteria by Thermal, Chemical, Enzymatic and Ultrasound Stresses.

During isolation, exopolysaccharides (EPS) from lactic acid bacteria are subject of thermal, chemical, enzymatic or ultrasound stress of different intensity that may affect macromolecular properties, for instance molecular mass or (intrinsic) viscosity. These parameters are, however, crucial, as they are associated with the technofunctional potential of EPS replacing commercial thickeners in nonfermented products. The aim of this study was to systematically examine treatments EPS are usually exposed to during isolation and to investigate the underlying degradation mechanisms.

How Capsular Exopolysaccharides Affect Cell Surface Properties of Lactic Acid Bacteria.

Some lactic acid bacteria are able to produce exopolysaccharides that, based on localization, can be distinguished in free and capsular or cell-bound exopolysaccharides (CPS). Up to now, the former were the focus of current research, mainly because of the technofunctional benefits they exhibit on fermented dairy products. On the other hand, CPS affect the surface properties of bacteria cells and thus also the textural properties of fermented foods, but data are very scarce.

Production and molecular structure of heteropolysaccharides from two lactic acid bacteria.

In the dairy industry, exopolysaccharides (EPS) produced in situ from lactic acid bacteria are of great interest because of their contribution to product texture. Some EPS cause ropiness which might be linked to specific physical and chemical EPS properties. EPS show a broad variety of chemical structures and, because analysis is rather complex, it is still a major challenge to establish structure-function relationships.

Test parameters and cell chain length of Streptococcus thermophilus affect the microbial adhesion to hydrocarbons assay: a methodical approach.

The microbial adhesion to hydrocarbons (MATH) test is one of the most common method to determine the hydrophobicity of cell surfaces. Despite its prevalence, no standard test parameters are used in literature, making a direct comparison of data almost impossible. Criticism also focuses on test parameters that may mask hydrophobic interactions and hence lead to erroneous test results.

Investigating the effect of sterilisation methods on the physical properties and cytocompatibility of methyl cellulose used in combination with alginate for 3D-bioplotting of chondrocytes.

For both the incorporation of cells and future therapeutic applications the sterility of a biomaterial must be ensured. However, common sterilisation techniques are intense and often negatively impact on material physicochemical attributes, which can affect its suitability for tissue engineering and 3D printing. In the present study four sterilisation methods, autoclave, supercritical CO (scCO) treatment, UV- and gamma (γ) irradiation were evaluated regarding their impact on material properties and cellular responses.

Shear treatment of starter culture medium improves separation behavior of cells.

A central step in the production of starter cultures is the separation of the cells from the fermentation medium, which is usually achieved by disk centrifuges. In case of microorganisms which produce exopolysaccharides (e.g.