Reducing Biofilm in Listeriamonocytogenesby Some Plant Extracts

Abstract

The results of reducing biofilm were determined by using methanol extract for 32different types of plant extracts. Determined the minimum inhibition concentration of these plant extracts, (1 -10) folds it means (100-1000) µg/ml of plant extracts according the plant activity adjusted minimum inhibition concentration (MIC) and then determined Sub minimum inhibition concentration (sub MIC) and used it as reducing biofilm agents by two methods: planktonic cells was treated with these extracts and sessile cells or biofilm was treated by these extracts.Quantification of biofilm reducing was carried out by using a microtiter plate assay and a spectrophotometric method. The result of methanol extracts of {nthemistinctoria (Matricariachamomilla), and Clove (Eugenia caryophyllata,, Salix candida, leaves of Quercusbrantii Oak, leaves of pomegranate (Punicagranatum and Sumac Rhusanacardiaceae)} were showed good antibiofilm activity against (Listeria monocytogenes) in both methods, while the majority of the extracts enhanced biofilm development. Combination extracts with antimicrobial agents showed mainly synergism and interaction was observed on inhibition of the biofilmwhile biofilm that produced by L. monocytogenes was resistance to most of the eight antimicrobial agents ((ampicillin (AMP),naldixic acid(NAL), neomycin (N), streptomycin (STR), chloramphenicol (CHL), rifampin (RIF), tetracyclin (TET) , and carbincillin (CAR) at final concentration used in this study. Keywords: Biofilm,Eugenia caryophyllata, Listeria monocytogenes, nthemistinctoria,Salix candida