Investigation of the effectiveness of Ascopyrone P as a food preservative

Ascopyrone P (APP), a novel antibacterial from fungi, was evaluated as a food preservative. Efficacy was generally assessed by comparing the time taken for test strains to grow to 106 CFU/g in food ±APP. In chilled chicken soup, 2000 mg kg−1 APP prevented Bacillus cereus, Listeria monocytogenes, Pseudomonas fluorescens, Salmonella and Escherichia coli reaching this threshold for >60 days. Good activity was also observed at 500–1000 mg kg−1 but not against L. monocytogenes. No activity was observed against Saccharomyces cerevisiae. Activity was reduced at 20 °C, although 2000 mg kg−1 was still effective against B. cereus and P. fluorescens. APP was less effective in chilled cooked meat systems and ineffective in raw meat. In a cooked meat system at 8 °C, bacteriostatic effect was generally observed at 2000 mg kg−1 against Salmonella typhimurium, E. coli and P. fluorescens but not against L. monocytogenes or Lactobacillus sake. Activity against Gram-negative enteric bacteria was enhanced by low temperature. In milk, 2000 mg l−1 was effective against P. fluorescens at chilled but not ambient temperature. APP was ineffective against yeasts and the mould Byssochlamys in apple juice. mum of 2000 mg kg−1 APP would appear to be necessary for antibacterial efficacy in food, although low-temperature storage may help. Observed variations in sensitivity may be related to APP stability, which decreases >pH 5.5. Toxicology testing is needed before consideration of APP for food use.