Bioprospecting of potentially probiotic lactic acid bacteria producing bacteriocins and vitamin B9 isolated from Coragyps atratus: application in vitro dynamic digestive system

• Grant number: 24/17310-7
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: July 01, 2025
• End date: June 30, 2028
• Field of knowledge: Biological Sciences - Microbiology - Applied Microbiology
• Principal Investigator: Ricardo Pinheiro de Souza Oliveira
• Grantee: Ana Clara Candelaria Cucick
• Host Institution: Faculdade de Ciências Farmacêuticas (FCF). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 18/25511-1 - Bioprospecting of bacteriocin-producing bacteria: from culture optimization to the application in animal production systems, AP.TEM

Abstract

The indiscriminate and improper use of antibiotics in humans and animal production has contributed to the rise of bacterial resistance, leading to the emergence of multi-resistant strains, which has become a major public health concern. There is an urgent and growing need to find alternatives that can enhance the natural defense mechanisms of both humans and animals, thereby reducing the reliance on antibiotics. Identifying strains of lactic acid bacteria (LAB) with probiotic potential and the ability to produce bacteriocins, as well as discovering new classes of safe and effective antimicrobials, is crucial in the fight against bacterial infections. To achieve this, it is necessary to explore diverse microbiomes, employing cutting-edge technological tools derived from recent scientific advancements in this field. This project aims to investigate the gut microbiota of vultures (Coragyps atratus)-birds with a remarkable ability to consume carcasses-whose unique microbiota has been largely unexplored. Due to their scavenging habits, these birds are constantly exposed to a variety of pathogens yet remain unaffected. This suggests they may possess distinct molecular and microbiological mechanisms for adapting to pathogen exposure, particularly through microbiota modulation. The objective of this project is to isolate and identify LAB strains that produce antimicrobial compounds effective against resistant pathogenic bacteria, while also assessing the probiotic potential and vitamin B9 production capabilities of the isolated strains. A probiotic mix will then be formulated with the selected strains, and its efficacy will be tested using dynamic models that simulate the gastrointestinal tract. Strains with a high capacity for bacteriocin production will be selected for further study. This will involve process optimization studies in bioreactors, compatibility testing among LAB strains, molecular studies to identify species and genes/metabolic pathways of interest, bacteriocin purification, and the subsequent formulation and microencapsulation of a probiotic mix. To demonstrate the efficacy of the developed product, in vitro studies will be conducted using dynamic digestive system models (TIM) that simulate the gastrointestinal tract of birds. This research is expected to contribute to reducing antibiotic use in animal production, enhancing food safety, and providing viable alternatives for combating bacterial resistance. (AU)