Partial characterization of probiotic lactic acid bacteria isolated from Chinese dairy products

A total of 246 bacterial isolates were collected from various food and animal sources within Nanning city, China. Sequencing the 16S rRNA gene revealed that 24.4% lactic acid bacteria (LAB). Initial screens identified three semi-hard cheese: Lactobacillus plantarum subsp. strains K3 K4 Lb. paracasei tolerans K8; one raw buffalo milk: E41 as having highest levels cell surface hydrophobicity auto-aggregation. Further characterization these showed all four completely stable after exposure to pepsin trypsin for 6 hours, K8 remained viable hours acidic conditions (pH 2.5) bile salts (0.3%). In addition, shown inhibit growth potential human pathogens, including methicillin resistant Staphylococcus aureus, Escherichia coli Salmonella typhi, with inhibition zones being >14 mm each target. Results this study suggested characterized LAB could survive passage through gastrointestinal tract, thus supporting need additional studies assess their probiotics.