*2.4. Microorganisms*

The antimicrobial activity was assessed on two bacteria, Gram-positive *Staphylococcus aureus* (ATCC 9144) and Gram-negative *Escherichia coli* (ATCC 11775) and six yeasts. The six yeasts comprised of a standard reference strain (ISO TC 34 SC 9 Joint Working Group 5/ISO 11133) *Candida albicans* (ATCC 10231) and weak-acid preservative resistant strains which are *Candida krusei* (ATCC 6258)*, Dekkera anomala* (ATCC 58985), *Rhodotorula mucilaginos*a (ATCC 20129), *Saccharomyces cerevisiae* (ATCC 38555) and *Schizosaccharomyces pombe* (ATCC 26189).
