Lactobacillus acidophilus La5 and Bifidobacterium lactis Bb12 cell surface hydrophobicity and survival of the cells under adverse environmental conditions.
Changes in the cell surface hydrophobicity (CSH) of probiotic bacteria Lactobacillus acidophilus La5 and Bifidobacterium lactis Bb12 and the survival of these cells were examined in response to varied cultivation conditions and adverse environmental conditions. An inverse linear relationship (P < 0.01) was detected between the CSH of intact L. acidophilus La5 and B. lactis Bb12 and survival of cells subjected to subsequent freezing/thawing, long-term storage or exposure to mineral and bile acids. The observed relationships were supported by significant correlations between the CSH and changes in composition of the cell envelopes (proteins, lipids and carbohydrates) of L. acidophilus La5 and B. lactis Bb12 examined using FT-IR spectroscopy and conventional biochemical analysis methods. The results also suggest that the estimates of hydrophobicity, being a generalized characteristic of cell surfaces, are important parameters to predict the ability of intact probiotic bacteria to endure extreme environments and therefore should be monitored during cultivation. A defined balance of cell components, which can be characterized by the reduced CSH values, apparently helps to ensure the resistance, improved viability and hence the overall probiotic properties of bacteria.
Institute of Microbiology and Biotechnology, University of Latvia, Kronvalda Boulevard 4, Riga 1010, Latvia. invizigota@inbox.lv
Laisana
L
Shakirova
Mara
M
Grube
Marita
M
Gavare
Lilija
L
Auzina
Peteris
P
Zikmanis
D001644:Bifidobacterium / Q000737:chemistry* / Q000187:drug effects / Q000502:physiology; D001647:Bile Acids and Salts / Q000633:toxicity; D005615:Freezing; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D007779:Lactobacillus acidophilus / Q000737:chemistry* / Q000187:drug effects / Q000502:physiology; D050296:Microbial Viability; D019936:Probiotics / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties
D001647:Bile Acids and Salts