Developing Robust Probiotic Consortia: A Methodological Optimization Approach

Area of Science:

• Microbiology
• Biotechnology
• Probiotics Research

Background:

• Effective probiotic consortia depend on understanding complex strain interactions.
• The role of microbial metabolites in probiotic compatibility is often overlooked in traditional assessments.

Purpose of the Study:

• To evaluate the impact of microbial strains and their secondary metabolites on compatibility for multi-strain probiotic formulation.
• To identify synergistic interactions mediated by metabolites in probiotic co-cultures.

Main Methods:

• Assessed antagonistic activity using the spot method to identify incompatible strains.
• Evaluated synergistic attributes by analyzing the effect of cell-free supernatants on co-culture growth.
• Identified bacterial isolates using 16S RNA sequencing.

Main Results:

• Strains PIG1FD and PIG1IR exhibited antagonistic effects, making them unsuitable for consortia.
• Cell supernatants from PIG6IR (Bacillus subtilis) and PIG5CI (Bacillus spizizenii) significantly promoted the growth of other strains.
• PIG5CI accelerated log phase entry by 0-2 hours, while PIG6IR did so by 5-6 hours.

Conclusions:

• Bacillus spizizenii BAB 7915 (PIG5CI) and Bacillus subtilis BAB 7918 (PIG6IR) are promising candidates for probiotic consortia due to metabolite-mediated growth promotion.
• This research provides a novel methodology for assessing probiotic compatibility, considering metabolite effects.
• Findings offer insights for developing advanced, multi-strain probiotic formulations.