Salmonella enterica subsp enterica serovar typhimurium

Foodborne L. coryniformis NA-3 was obtained from our own laboratory and isolated from Chinese sauerkraut. The bacteria stored at −80 °C was cultured in solid Man, Rogosa and Sharpe (MRS) (Solarbio, Beijing, China) broth at 37 °C for 48 h. A single colony of L. coryniformis NA-3 was transferred into 10 mL of MRS broth and grown at 37 °C for 48 h under anaerobic conditions. Bacillus cereus (CICC 21261), Salmonella enterica subsp. enterica serovar Typhimurium (CICC 22956/ATCC 14028) and Escherichia coli O157:H7 (CICC 10907) were purchased from the China Center of Industrial Culture Collection (CICC), and Staphylococcus aureus (CGMCC 1.291) was purchased from the China General Microbiological Culture Collection Center (CGMCC). The four pathogenic bacteria were grown in trypticase soy broth (TSB) solid medium at 37 °C for 24 h under aerobic conditions. A single colony was transferred into 5 mL of fresh TSB broth and grown for 24 h at 37 °C with shaking. A one-percent bacterial suspension (10⁸ CFU/mL) was inoculated in another 5 mL of fresh TSB medium and cultured for 24 h at 37 °C with continuous shaking in order to obtain a pathogenic bacteria suspension for the following applications.

Mangiferin references at analytical standards (purity of ≥98%) were purchased from Sigma-Aldrich (St. Louis, MI, USA). HPLC-grade ethanol, methanol, and phosphoric acid at analytical levels were purchased from Merck (Darmstadt, Germany). Tested bacteria, including three Gram-positive (Bacillus cereus (B. cereus) ATCC 11778, Bacillus subtilis (B. subtilis) ATCC 6633, and Staphylococcus aureus (S. aureus) ATCC 25923) and three Gram-negative (Escherichia coli (E. coli) ATCC 25922, Pseudomonas aeruginosa (P. aeruginosa) ATCC 9027, and Salmonella enterica subsp. enterica serovar Typhimurium. (S. typhimurium) ATCC 13311), were purchased from the American Type Culture Collection (ATCC, Rockville, MD, USA).