Aggregation ability of potential probiotic Lactobacillus plantarum strains

Abstract

Aggregation is the process of reversible gathering of bacterial cells belonging to the same bacterial strain (autoaggregation) or two different bacterial strains (coaggregation). Autoaggregation ability of probiotic bacteria correlates with adhesion, which is a prerequisite for colonization and protection of gastrointestinal tract, while coaggregation provides close interaction with pathogenic bacteria.In this experiment the aggregation ability of three potential probiotic strains of Lactobacillus plantarum were investigated. Coaggregation with different food– borne pathogens: Salmonella enterica serotype Typhimurium, Listeria monocytogenes EGD strain and enterohaemorrhagic Escherichia coli (EHEC) was also studied. The results showed that all Lactobacillus strains when cultivated in broth had better autoaggregation and coaggregation abilities then those cultivated on agar. After 24 hours almost 80 % of Lactobacillus aggregated. All lactobacilli coaggregated similarly with selected food-borne pathogens. All three strains of L. plantarum possess the ability to autoaggregate and coaggregate, which is an important feature in the selection of probiotic bacteria.