Characterization of Lactobacillus johnsonii KUNN19-2 and Pediococcus pentosaceus KUNNE6-1 Isolated from Thai-Style Fermented Pork (Nham) for Their Probiotic Properties in the Gastrointestinal Tract and Immunomodulation

Abstract

Lactobacillus johnsonii KUNN 19-2 and Pediococcus pentosaceus KUNNE 6-1 are resistant to antibiotics (chloramphenicol, tetracycline and streptomycin), and inhibit the growth of Bacillus cereus, Leuconostoc mesenteroides and Staphylococcus aureus. They enhance good sensory characters in Nham (fi rmness, color and fl avor). These promising properties have raised interest in further investigation; thus, the probiotic properties were the aim of the study. The survival of Lb. johnsonii KUNN19-2 and P. pentosaceus KUNNE6-1 under gastric conditions with a low pH of 1.5 were 60.40 and 40.51%, respectively, and in the presence of pepsin were 70.97 and 58.80%, respectively. Their survival rates under the intestinal conditions with pancreatin and bile salts were 54.47–57.14%. However, when Lb. johnsonii KUNN19-2 and P. pentosaceus KUNNE6-1 were exposed to these gastric conditions and then continued to the intestinal conditions, their survival rates were lowered to 30.84 and 19.40%, respectively. Heat-treated cells of Lb. johnsonii KUNN 19-2 induced Immunoglobulin G (IgG) production from T and B cells proliferation in BALB/c mice spleen cells by an ex vivo test of 3.66 and 4.24 μg.mL-1, respectively, whereas P. pentosaceus KUNNE 6-1 induced IgG production from B cells proliferation of 3.83 μg.mL-1. These results could provide preliminary information on a future potential probiotic candidate for probiotic Nham with an immune-stimulating function.