Inhibition biofilm formation and cells infection of Salmonella and Staphylococcus by extracts of potential probiotic strains: Application of mixture design

The mixture design approach, becoming increasingly common in several sciences, was used to find biological control treatment for pathogenic bacteria. The current study examined the effectiveness of a microbial extract consortium in inhibiting and eradicating biofilms as well as cell infections. There were three different combinations of probiotic strain extracts (Bacillus (A), Lactobacillus (B), and Candida famata (C)) used in this study. The levels of biofilm inhibition, eradication, and cell infection of Salmonella were improved where the consortiums were 25% (A) and 75% (B); 73% (A) and 27% (C); 66% (B) and 33% (C) respectively. The best effects of probiotic extract combinations on Staphylococcus biofilm formation were 27% (A) and 73% (B). However, anti-infective activity was obtained with a combination composed of 50% from each probiotic extract (B and C). Using a mixing design is shown to be an effective strategy for selecting the best combination of components, exploiting extracts under the optimal conditions, and conferring maximum protection against Gram-negative and Gram-positive pathogenic bacteria. Results indicated a positive effect of the different combinations on the ability to form biofilms and infect cells of the tested pathogenic strains.