Paper Title
In Vitro Evaluation of Properties of Lactobacillus Strains

Abstract
Use of probiotics represents a promising approach to control global gastrointestinal infections. Studying anti-infective characteristics of metabolic products from Lactobacillus casei subsp. casei and Lactobacillus plantarum subsp. plantarum against Escherichia coli and Staphylococcus aureus as human pathogens was carried out in this context.High tolerance was observed by Lactobacillus strains for some essential parameters such as low pH and bile salt. The strains alsoexhibited effective aggregation and hydrophobicity characters while, L. plantarum showed effective co-aggregation percentage of 19.6% with E. coli. Both Lactobacillus strains showed inhibitory activity against E. coli and S. aureusAlteration or rupture in cell morphology was also investigated by SEM analysis. Consequently, L. casei and L. plantarum strains may be considered as a good candidate for bio-protective agents. Keywords - Lactobacilluscasei, Lactobacillus Plantarum, Probiotics, Antibacterial Property, Viability