Zoom-koom is a traditional fermented beverage from Burkina Faso produced from millet or sorghum grains. A
total of 33 Lactic acid bacteria (LAB) that produce exopolysaccharides (EPS) were isolated from zoom-koomand
characterized in order to select the most efficient as starter cultures to improve the quality of zoom-koom.
Physiological and morphological characteristics were determined using growth tests and microscopic
observation, respectively. Activities of starch degrading enzymes (amylases) were performed using biochemical
methods. Antimicrobial activities were determined using disc diffusion assay and overlay method. Genotypic
characterization and identification of selected LAB EPS synthetizing isolates which were able to produce
antimicrobial compound were performed through 16S rRNA sequencing. EPSs Structures of selected LAB
isolates were determined using NMR spectroscopy. Among LAB isolates 76% was hetero-fermentative while the
other was homo-fermentative. Some isolates (15%) could grow in the presence of bile and esculin and 12% were
able to grow on MRS-starch. Although all the isolates were able to produce EPSs, only 6% were efficient
producers. Among the screened LAB isolates, 7had inhibitory activities against Escherichiacoli81 nr.149 SKN
541, Pseudomonas aeruginosa ATCC and Salmonella typhimurium O:1036340P/t49. In addition 6 isolates
displayed antifungal activities against Aspergillus fumugatus, Aspergillus flavus and Aspergillus niger. The 16S
rRNA sequencing showed that most of the isolates were clustered with Weissella cibaria/confusa and the others
were clustered with Lactobacillus plantarum/pentosus and Lactococcus lactis/garvieae. The NMR spectroscopy
showed that excreted EPSs are ramified glucanpolyaccharides containing α-(13) and α-(16) linkages, where
the later are the main chains.

Lactic acid bacteria Antimicrobial Exopolysaccharides Starter cultures Zoom-koom Sorghum