Effect of Acids on Selenite Inhibition of Salmonella typhimurium and Salmonella dublin.
The minimum pH for growth (MPG) in selenite-cystine enrichment medium was determined for a number of acids. The MPG for lactic, citric, hydrochloric, aspartic, malic, succinic, pyruvic, and tartaric acids was 5.80; acetic acid was considerably more inhibitory, giving a MPG of 6.30-6.40; the MPG's for fumaric and pyruvic acids were 6.00 and 5.70, respectively. The least inhibitory acid was α-ketoglutaric acid which gave a MPG lower than or equal to 5.1. Inoculum size had little or no effect on the MPG.