Antimicrobial effects of curcumin against L. monocytogenes, S. aureus, S. Typhimurium and E. coli O157:H7 pathogens in minced meat

Abstract

ABSTRACT:The aim of this study was to determine the antimicrobial efficacy of curcumin, one of the active components of the Curcuma longa (turmeric) plant, against food pathogens in a minced meat medium. Salmonella Typhimurium ATCC 14028, Listeria monocytogenes ATCC 7644, Escherichia coli O157:H7 ATCC 33150 and S. aureus ATCC 25923 strains were used as food pathogens. Minimum inhibitory concentrations (MICs) were determined using the macrodilution method. MIC values for curcumin were found to be 125 µg/ml for L. monocytogenes and S. aureus, and 250 µg/ml for S. Typhimurium and E. coli O157:H7. Food pathogens were added to the minced meat at 10 4 CFU/g (including the control group) and curcumin at doses of 0.5%, 1% and 2% (except the control). The curcumin-supplemented minced meat and control were analysed 0-7 days later. At the end of seven days, it was seen that the 2% dose of curcumin had lowered L. monocytogenes and S. aureus counts by approximately 3 log CFU/g, and E. coli O157:H7 and S. Typhimurium counts by approximately 2 log CFU/g; the 1% dose had lowered L. monocytogenes, S. aureus, E. coli O157:H7 and S. Typhimurium counts by approximately 2 log CFU/g; and that the 0.5% curcumin dose had lowered L. monocytogenes and S. aureus count by approximately 2 log CFU/g, and E. coli O157:H7 and S. Typhimurium count by approximately 1 log CFU/g. Changes in bacterial counts were found to be statistically significant (P ≤ 0.05). It was observed that antibacterial effect increased in direct proportion to dose, while sensory approval decreased. In this study, 0.5% and 1% curcumin doses were determined to be sensorily acceptable. It was concluded that, in view of the scientific benefits and antimicrobial efficacy of curcumin, it may be used instead of, or in smaller doses together with preservative additives in foods where colour change is not important.

Curcumin: Natural Antimicrobial and Anti Inflammatory Agent

“…These findings are in accordance with a recently published study by Adamczak et al [27]. Significantly higher antimicrobial activity of curcumin against Grampositive than Gram-negative bacteria was also reported by other authors [30,31]. This is explained with the difference in the structure of bacterial cell walls as the cells of Gram-positive bacteria are not surrounded by an outer membrane.…”

“…This is explained with the difference in the structure of bacterial cell walls as the cells of Gram-positive bacteria are not surrounded by an outer membrane. The cells of Gram-negative bacteria are more resistant due to the presence of an outer membrane that prevents antimicrobial agents to reach and damage the inner membrane of the cell wall [31]. Furthermore, results of this study implied that the application of higher concentrations of curcumin solutions results in a larger diameter of zones of inhibition.…”

“…So far, phytochemicals have remained the leading source for potential antimicrobial agents, whether investigated independently or in a combination with another substance [2,25]. Recent studies have demonstrated a wide range of antimicrobial properties of curcumin mediated by different mechanisms, such as alteration of gene expression, inhibition of bacterial DNA replication and disruption of the bacterial cell membrane [26][27][28].Literature data demonstrate the beneficial and preventive role of curcumin against various microorganisms [29][30][31]. Despite various studies evaluating the antimicrobial activity of curcumin, further research is required with different concentrations against different strains of microorganisms.…”

Curcumin, a Natural Antimicrobial Agent with Strain-Specific Activity

“…Other authors have also reported a high sensitivity of these pathogens to curcumin, although the above-mentioned species have been examined to varying degrees. A lot of data exists for S. aureus (e.g., [20,32,34,35,37,54]), while in the case of S. pyogenes [20,31,33,55], and A. lwoffii [20], they are few. The very strong antimicrobial activity of curcumin, probably due to the use of acetone as a solvent, was shown in the studies of Lutomski et al [20].…”

Vacuum curcumin infusion in cooked oysters (Crassostrea gigas) to increase their shelf life

“…Xi, Liu, and Su (2012) immersed oyster meat into green tea extract solution to reduce V. parahaemolyticus count and increase their shelf life at normal atmosphere pressure. For other foods, Sandikci Altunatmaz et al (2016) used curcumin in ground beef against pathogens with good results. Bellary, Indiramma, Prakash, Sowbhagya, and Rastogi (2017) used curcumin as a natural dye on coconut slices and banana slices; Kaba, Özer, and Çorapcı (2017) used curcumin on smoked fish as a natural colorant.…”