Effects of propolis extracts on biogenic amine production by food- borne pathogens

Abstract

The impacts of water and ethanolic extracts of propolis on growth of Gram- positive and Gram-negative food-borne pathogens and their biogenic amine production were investigated. Ethanolic extracts of propolis had lower minimum inhibitory concentration (MIC) than that of water extract. Undiluted water extract of propolis (100%) was more effective on growth inhibition of Staphylococcus aureus (29.5 mm) and Klebsiella pneumoniae (26.5 mm) than antibiotics. The effect of propolis on biogenic amine production showed a discrepancy depending on bacterial strains, specific amine and extract type. Water or ethanolic extracts of propolis induced about 81-fold lower histamine accumulation by Yersinia enterocolitica. The study results suggested that both propolis extracts tested could be used as antimicrobial as they inhibit biogenic amines which were toxically important, although both propolis extracts exerted variability even among Gram- positive or negative bacteria. Moreover, stimulation of serotonin production by bacteria in the presence of propolis extracts emphasized important aspects of propolis for utilization in foods.

Keywords

• propolis
• food-borne pathogen
• antimicrobials
• histamine
• serotonin