Molecular characterization of native isolates of lactic acid bacteria, bifidobacteria and yeasts for beneficial attributes

Abstract

In a changing scenario of food habits being associated with wellness factors through the concepts of probiotics and prebiotics, an attempt has been made to characterize on molecular basis, the desirable benefits associated with natural isolates of lactic acid bacteria, bifidobacteria, and yeasts. From a diverse range of foods and related samples, based on conventional microbiological protocols, three well-characterized natural isolates of Lactobacillus plantarum MTCC 5422, Bifidobacterium adolescentis MTCC 5423 and Saccharomyces cerevisiae MTCC 5421 were selected. The cultures of L. plantarum and B. adolescentis showed positive polymerase chain reaction (PCR) amplification with oligonucleotide primers targeting genus-specific 16 S rRNA for Lactobacillus and fructose-6-phosphate phosphoketolase for Bifidobacterium. Similarly, species-specific positive amplification in PCR was observed with primers of phytase (acid phosphatase) in S. cerevisiae and alpha-D: -galactosidase and bile salt hydrolase in L. plantarum and B. adolescentis. The cultures of L. plantarum and B. adolescentis exhibited a broad spectrum antibacterial activity against selected foodborne pathogenic bacterial species and tolerance to acid and bile. Gene sequence of respective PCR-amplified products confirmed the genetic identity of the isolated cultures as L. plantarum and B. adolescentis showing 99% homology with the documented sequence of established gene bank.

Effect of whey protein – alginate wall systems on survival of microencapsulated Lactobacillus plantarum in simulated gastrointestinal conditions

“…The bacterial strain used in this study was L. plantarum (mtcc 5422) culture, isolated from fermented batter of cereal/legume (Roopashri & Varadaraj, 2009). All the glasswares used in this experiment were sterilized at 121°C for 15 min.…”

Microencapsulation of Lactobacillus plantarum MTCC 5422 in fructooligosaccharide and whey protein wall systems and its impact on noodle quality

“…The probiotic bacterial strain Lactobacillus plantarum (MTCC 5422), isolated from fermented batter of cereal/ legume (Roopashri and Varadaraj 2009) was used in this study. MRS broth, MRS agar, extra pure sodium chloride, methanol and bile salt were procured from HiMedia Laboratories, Mumbai, India.…”

A novel Bifidobacterium infantis-mediated TK/GCV suicide gene therapy system exhibits antitumor activity in a rat model of bladder cancer

“…In this study, we developed and validated a novel suicide gene therapy system by exploring the hypoxic environment of solid tumors and the anaerobic metabolism features of Bifidobacterium infantis bacterial cells. Our results have demonstrated that the Bifidobacterium infantis/thymidine kinase suicide gene therapy system may be used as a targeted cancer therapy [1-5]. …”