I think the question you are asking is "why can lactic acid bacteria survive in a saline environment whereas some harmful bacteria types cannot?" I believe the

I think the question you are asking is "why can lactic acid bacteria survive in a saline environment whereas some harmful bacteria types cannot?" I believe the answer is that "bad" bacteria CAN oftentimes survive in environments with high-salinity [1], but struggle to compete with lactic-acid bacteria (i.e. "good" bacteria - LAB) in the presence of both a saline environment as well as a high ph environment. LAB also engage in antimicrobial activities within your gut [2] likely using bacteriocins as the mechanism. Salt generally inhibits fungal growth though. [1] https://academic.oup.com/femsle/article/243/2/373/495985 https://academic.oup.com/femsle/article/243/2/373/495985 [2]https://pubmed.ncbi.nlm.nih.gov/15374659/ https://pubmed.ncbi.nlm.nih.gov/15374659/