ISSN:
1574-6968
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Biology
Notes:
It is now well established that physicochemical properties of exopolysaccharides (EPS) can vary between strains of a given species and according to growth conditions. The EPS production of four strains of Lactobacillus bulgaricus was monitored during growth in milk and in a chemically defined media. All strains, including the non-ropy one, produced EPS. The monosaccharide composition, molar mass (Mw), and intrinsic viscosity of these EPS were determined and compared. Further characterization using high-performance size-exclusion chromatography revealed the presence of two fractions in all EPS: one fraction exhibited a high Mw and a high intrinsic viscosity while the other had a low Mw and a low intrinsic viscosity. Strikingly, the EPS synthesized by the non-ropy strain was mainly composed of the low-Mw fraction while for the ropy strains, the fraction of high Mw varied between 43 and 90%. According to our results, we propose that the ratio between the high-Mw and low-Mw fractions is critical for the texturing properties of L. bulgaricus EPS.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1016/S0378-1097(03)00214-3
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