Antimicrobial effects of curcumin on minced meat contaminated with foodborne pathogens

Abstract

Curcuminhas antimicrobial and anticancer, antioxidant, antiseptic properties and natural colorant, in addition to this there are many studies carry on due to its antimicrobial effect recently it has been used in food. In this study, antimicrobial effect of curcumin were determined for activity against foodborne pathogenic microorganisms in minced meat. Curcumin (Sigma C7727) was obtain from Sigma-Aldrich Chemicals. Fresh minced meat and foodborne pathogens (S. aureus and L.monocytogenes, E.coli O157:H7 and S.Typhimurium) were used. Statistical Analysis JMP software version 6.0.0 was used to perform the statistical analyses. When signifi cant differences were found, the Least Signifi cant Difference test was used to determine the differences among means. Determinations of the minimum inhibitory concentration (MIC) of foodborne pathogenswere determined by broth macrodilution using two-fold serial dilutions.Minced meat immediately analysed for foodborne pathogens and was stored under cold (-180 C). Minced meat was divided in to fi ve portions (control andwith bacteria group). Prior to minced meat inoculation with pathogen (104 cfu/g and the addition of curcumin (0.5%, 1%, 2%), wereanalysed throughout0-7th days. The curcumin MIC values were found125 µg/mL, againstL. monocytogenes and S. aureus, 250µg/mLagainst SalmonellaTyphimurium and E. coli O157:H7. Results ofthe antibacterial activity of curcumin at 0.5%, 1%, 2% levels in minced meat showed that use of curcumin at 2% reduced the L.monocytogenes, S.aureuscount approximately 3 log cfu/g and E.coli O157:H7, S. Typhimurium count approximately 2 log cfu/g; use of curcumin at 1% dosage reduced the L.monocytogenes, S.aureus, E.coli O157:H7, andS.Typhimurium count approximately 2 log cfu/g; use of curcumin at 0.5% dosage reduced the L.monocytogenes, S.aureus count approximately 2 log cfu/g and E.coli O157:H7, S. Typhimurium count approximately 1 log cfu/g after 7 days.These changes in the number of bacteria was found to be statistically signifi cant (p?0.05).