Role of Lactic Acid Bacteria as a Biosanitizer To Prevent Attachment of Listeria monocytogenes F6900 on Deli Slicer Contact Surfaces

Abstract

The study was conducted to evaluate the attachment of three lactic acid bacteria (LAB) strains and their combination in a cocktail, to stainless steel coupons from a deli slicer, and their ability to inhibit the attachment of Listeria monocytogenes. In a previous study, three LAB strains, Pediococcus acidilactici, Lactobacillus amylovorus, and Lactobacillus animalis, were isolated from ready-to-eat meat and exhibited antilisterial effect. In the study reported here, hydrophobicity tests were determined according to the method of microbial adhesion to solvent. The attachment of the cells was evaluated on stainless steel coupons from deli slicers. Extracellular carbohydrates were determined with a colorimetric method. Based on these tests, L. animalis exhibited the greatest hydrophobicity (26.3%), and its adherence increased sharply from 24 to 72 h, whereas L. amylovorus yielded the lowest hydrophobicity (3.86%) and was weakly adherent. Although P. acidilactici had moderate hydrophobicity (10.1%), it adhered strongly. The attached LAB strains produced significantly (P < 0.05) higher total carbohydrates than their planktonic counterparts did, which is an important characteristic for attachment. Three conditions were simulated to evaluate the ability of the LAB cocktail (10(8) CFU/ml) to competitively exclude L. monocytogenes (10(3) CFU/ml) on the surface of the coupons. The coupons were pretreated with the LAB cocktail for 24 h prior to the addition of L. monocytogenes, simultaneously treated with the LAB cocktail and L. monocytogenes, or pretreated with L. monocytogenes 24 h prior to the addition of the LAB cocktail. The LAB cocktail was able to reduce the attachment L. monocytogenes significantly (P < 0.05). The LAB cocktail indicated potential attachment on stainless steel and bacteriostatic activity toward L. monocytogenes attached on stainless steel, which indicates a possible role for LAB as a biosanitizer in the food industry.

Strategies for Pathogen Biocontrol Using Lactic Acid Bacteria and Their Metabolites: A Focus on Meat Ecosystems and Industrial Environments

“…Similarly, high antilisterial efficacy was achieved by pre-established biofilms of bacteriocin–producing LABs used as biosanitizers. Biofilm settlements of L. plantarum 35d in a small-scale model, as well as pretreatment with an LAB ( P. acidilactici , L. amylovorus , and L. animalis ) cocktail on SS coupons cut from the blade of a deli slicer machine, directly competed with L. monocytogenes for attachment to surfaces with a significant pathogen exclusion [ 113 , 114 ]. The probiotic strains L. paracasei and L. rhamnosus were reported to effectively inhibit biofilm formation by L. monocytogenes through the mechanisms of competition, exclusion, and displacement [ 115 ].…”

Current Knowledge on Listeria monocytogenes Biofilms in Food-Related Environments: Incidence, Resistance to Biocides, Ecology and Biocontrol

“…In line with these above mentioned studies, different comparative studies have shown that the effectiveness of LAB against pre-formed biofilms of L. monocytogenes (approach known as displacement mechanism) is significantly lower than on adhesion and biofilm formation by competitive exclusion [ 158 , 159 , 160 ]. That is, acting early would seem to be most appropriate to prevent biofilm formation.…”

“…This effect has been defined as competitive exclusion. As a result, a high number of different strains has been shown to be highly effective: Enterococcus durans [ 153 , 154 ], Enterococcus faecium [ 146 ], L. lactis [ 153 , 154 , 155 ], Lactobacillus plantarum and Enterococcus casseliflavus [ 156 ], Leuconostoc mesenteroides [ 157 ], L. sakei [ 150 , 158 ], Pediococcus acidilactici , Lactobacillus amylovorus and Lactobacillus animalis [ 159 ], Lactobacillus acidophilus , Lactobacillus casei , Lactobacillus paracasei and Lactobacillus rhamnosus [ 160 ], and Lactobacillus paraplantarum [ 161 ], among others.…”

Palm Juice / Nira (Arenga pinnata (Wurmb) Merr.), A Source of Lactic Acid Bacteria from North Sumatra

“…animalis, Lb. amylovorus, Pediococcus acidilactici) and found a succesful prevention of biofilm-forming Listeria monocytogenes, a food spoilage bacteria [13]. However, it should be noted that biofilm-forming LAB also caused notable cases like food spoilage and deterioration in food industry [14,15].…”