The effect of slight pH changes in gastric conditions on the survival of Listeria monocytogenes

• Author(s): Oliveira, Mónica ; Barbosa, Joana ; Teixeira, Paula
• Date: 2024
• Persistent ID: http://hdl.handle.net/10400.14/48225
• Origin: Veritati - Repositório Institucional da Universidade Católica Portuguesa
• Document Type: Conference object
• Language: English
• Contributor(s): Veritati

Description

Introduction and Objectives: Listeria monocytogenes, the etiological agent of human listeriosis, poses a substantial threat as a lethal intracellular pathogen after the consumption of contaminated foods[1]. Invasive listeriosis is particularly severe in vulnerable populations, including pregnant women, newborns, the elderly, and immunocompromised individuals[2]. While all strains are conventionally considered equally virulent, acknowledging the inherent variability, the absence of reliable biomarkers hampers the differentiation of strains based on virulence[2]. However, resistance to the gastrointestinal tract could be viewed as a potential discriminatory factor, as invading strains must endure the challenges posed by the gastrointestinal environment for successful establishment. Upon ingestion, on its passage through the human gastrointestinal tract, L. monocytogenes faces multiple hurdles, which can significantly affect its ability to cause an infection. One of the many hurdles is the harsh environment of the stomach. Hydrochloric acid (HCl) secretion in the stomach plays a pivotal role in raising acidity to levels lethal for most bacteria. This work aimed to assess the impact of lowering pH levels on the survival of selected Listeria monocytogenes strains.