Antimicrobial activity of essential oils and structurally related synthetic food additives towards Clostridium perfringens.

ABSTRACT

AIMS: To assess the potential of essential oils and structurally related synthetic food additives in inhibiting the growth of Clostridium perfringens for the control of necrotic enteritis in chickens. METHODS AND RESULTS: The antimicrobial activity of essential oils/compounds was measured by determining the inhibition of bacterial growth. Thirty-three of 66 oils/compounds exhibited > or =80% inhibition. Seven with the highest potency were further studied. The oils/compounds had MIC(95) values between 167 and 425 microg ml(-1). Most of them were tolerant to low pH (2.0) and exhibited minor or no inhibition of Lactobacillus isolates from the chicken intestine. When mixed with chicken ileal digesta, the oils/compounds retained their efficacy against C. perfringens, but had little effect on the total number of lactobacilli and anaerobic bacteria in the digesta. CONCLUSIONS: Some essential oils/compounds demonstrated good potential in controlling C. perfringens. SIGNIFICANCE AND IMPACT OF THE STUDY This study has identified candidates of essential oils/compounds for in vivo studies for the control of necrotic enteritis in chickens.