Exopolysaccharide production by lactose-hydrolyzing bacteria isolated from traditionally fermented milk

Date
2009
Authors
Bauer R.
Bekker J.P.
Wyk N.v.
du Toit C.
Dicks L.M.T.
Kossmann J.
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
With increasing consumer demands for safer, healthier and more natural products, bacterially produced exopolysaccharides (EPSs) are becoming a viable option as an additive in designer-type foods. Fresh milk samples from cattle and sheep were collected from informal settlements in South Africa. After a three day incubation period at 25 °C, 550 bacterial strains were isolated and evaluated for EPS production from lactose as sole carbon source. Strains producing EPS on lactose were identified to species level with 16S rRNA gene sequencing and encompass 11 Gram-positive and 6 Gram-negative bacteria. EPS production was assigned for the first time to members of the species Staphylococcus hominis and Enterococcus lactis, and also to apparently novel species of the genera Sphingomonas and Acinetobacter. The polymers consisted mainly out of galactose and glucose, while a few isolates also incorporated rhamnose. Isolates produced diverse biopolymers as seen by significant differences in monomer ratios. © 2009 Elsevier B.V. All rights reserved.
Description
Keywords
exopolysaccharide, galactose, glucose, lactose, rhamnose, RNA 16S, Acinetobacter, Acinetobacter johnsonii, article, bacterial gene, bacterial strain, bacterium identification, bacterium isolation, carbon source, Comamonas, Comamonas denitrificans, controlled study, cow, Enterobacter aerogenes, Enterococcus, Enterococcus lactis, Escherichia coli, fermentation, gene sequence, Gram negative bacterium, Gram positive bacterium, incubation temperature, incubation time, milk, nonhuman, nucleotide sequence, Propionibacterium acnes, sheep, Sphingomonas, Sphingomonas echinoides, Staphylococcus hominis, Acinetobacter, Animals, Bacteria, Base Sequence, Cattle, Enterococcus, Fermentation, Hexoses, Hydrolysis, Lactose, Milk, Polysaccharides, Bacterial, RNA, Ribosomal, Sequence Homology, Sheep, South Africa, Sphingomonas, Staphylococcus hominis, Acinetobacter, Bacteria (microorganisms), Bos, Enterococcus lactis, Negibacteria, Ovis aries, Posibacteria, Sphingomonas, Staphylococcus hominis
Citation
International Journal of Food Microbiology
131
03-Feb