Characterization of a bovine isolate Lactobacillus mucosae DPC 6426 which produces an exopolysaccharide composed predominantly of mannose residues
Article first published online: 11 JUN 2014
© 2014 The Society for Applied Microbiology
Journal of Applied Microbiology
Volume 117, Issue 2, pages 509–517, August 2014
How to Cite
London, L.E.E., Price, N.P.J., Ryan, P., Wang, L., Auty, M.A.E., Fitzgerald, G.F., Stanton, C. and Ross, R.P. (2014), Characterization of a bovine isolate Lactobacillus mucosae DPC 6426 which produces an exopolysaccharide composed predominantly of mannose residues. Journal of Applied Microbiology, 117: 509–517. doi: 10.1111/jam.12542
- Issue published online: 18 JUL 2014
- Article first published online: 11 JUN 2014
- Accepted manuscript online: 16 MAY 2014 12:39AM EST
- Manuscript Accepted: 9 MAY 2014
- Manuscript Revised: 28 APR 2014
- Manuscript Received: 13 FEB 2014
- Enterprise Ireland. Grant Number: CF/2013/3030
- Science Foundation Ireland (SFI)
- SFI CSET. Grant Number: 07/CE/B1368
- Lactobacillus mucosae;
To characterize Lactobacillus strains with EPS-producing ability compared with non-EPS-producing lactobacilli of the same species for technological performance including simulated gastrointestinal tract (GIT) conditions.
Methods and Results
Characterization of EPS-producing Lactobacillus mucosae DPC 6426 in detail based on 16S rRNA sequencing, and EPS production using scanning electron and atomic force microscopy. The EPS was found to consist of mannosyl residues, with mannose, glucose and galactose found to be the major sugar residues present in an approximate ratio of 3: 2: 2. The strain was compared to non-EPS-producing Lact. mucosae DPC 6420 following exposure to salt, bile, acid and heat stresses. Lact. mucosae DPC 6426 exhibited twofold increased (P < 0·05) survival during 120-min exposure to 5 mol NaCl, threefold increased survival during 90-min exposure to 0·7% (w/v) bile (P < 0·05), threefold increased survival when exposed to simulated gastric juice (P < 0·001) for 10 min and fivefold increased survival during 60-min exposure to HCl (P < 0·01) compared with Lact. mucosae DPC 6420. Furthermore, Lact. mucosae DPC 6426 was found to be more heat tolerant (P < 0·001) compared with Lact. mucosae DPC 6420 during 30-min exposure to 55°C.
These data indicate that the EPS-producing Lact. mucosae DPC 6426 exhibits technological and biological robustness compared with a non-EPS-producing Lact. mucosae strain.
Significance and Impact of the Study
The data implicate the potential suitability of EPS-producing Lact. mucosae DPC 6426 in food applications and/or as a probiotic culture.