The composition of sumac (Rhus coriaria L.) essential oil and its antimicrobial effect on some food borne bacteria

Bacteria are responsible for a large part of the food poisoning. Application of natural preservatives for protection foods from microbial spoilage and to control the occurrence of foodborne pathogens has become an important issue worldwide. The aim of this study was to investigate the composition of sumac (Rhus coriaria L.) essential oil and its antimicrobial effect on some food borne bacteria. The antimicrobial activity of R. coriaria L. essential oil was tested against some foodborne bacteria including: Pseudomonas aeruginosa, Yersinia enterocolitica, Klebsiella pneumonia, Listeria monocytogenes and Streptococcus pyogenes by microdilution method. Furthermore, sumac fruit essential oil was also investigated to determine the chemical compositions by the gas chromatography (GC/MS) method. The essential oil showed a strong antimicrobial activity with a concentration dependence and a broad antimicrobial spectrum for all tested bacteria species. Streptococcus pyogenes was found to be the most sensitive Gram positive bacteria with a minimum inhibitory concentration (MIC) of 0.156 mg/ml and Pseudomonas aeruginosa was the most resistant bacteria with a minimum inhibitory concentration (MIC) of 2.5 mg/ml. Sumac essential oil showed more antibacterial effect against Streptococcus pyogenes and Listeria monocytogenes isolates in comparison with other tested bacteria (P<0.05). Eleven constituents in the fruit’s essential oil were identified. The predominant compounds in the essential oil were trans-Caryophyllene (22.3%) and Butanedioic acid, and diethyl ester (21.01%). Our findings suggest the possibility of using the essential oil of R. coriaria L. as a novel source of natural antimicrobial agents for the food and pharmaceutical industries and herbal therapeutic.