Open AccessComparison of the thickening properties of four Lactobacillus delbrueckii subsp. bulgaricus strains and physicochemical characterization of their exopolysaccharides 1
Author(s) -
Petry Sandrine,
Furlan Sylviane,
Waghorne Earle,
Saulnier Luc,
Cerning Jutta,
Maguin Emmanuelle
Publication year - 2003
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1016/s0378-1097(03)00214-3
Subject(s) - lactobacillus delbrueckii subsp. bulgaricus , lactobacillus , strain (injury) , intrinsic viscosity , polysaccharide , chemistry , food science , lactobacillaceae , fraction (chemistry) , viscosity , monosaccharide , molar mass , chromatography , biology , materials science , biochemistry , organic chemistry , fermentation , polymer , composite material , anatomy
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 ( M w ), 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 M w and a high intrinsic viscosity while the other had a low M w and a low intrinsic viscosity. Strikingly, the EPS synthesized by the non‐ropy strain was mainly composed of the low‐ M w fraction while for the ropy strains, the fraction of high M w varied between 43 and 90%. According to our results, we propose that the ratio between the high‐ M w and low‐ M w fractions is critical for the texturing properties of L. bulgaricus EPS.