Surface hydrophobicity, nutritional contents affect Staphylococcus aureus biofilms and temperature influences its survival in preformed biofilms

Abstract

The present study investigates the effect of surface hydrophobicity and media on in vitro biofilm formation potential of S. aureus isolates from two dairies. There was lack of correlation between biofilm formation potential of S. aureus and sampling points but not with the source of isolation. Biofilm formation was more pronounced on hydrophobic polypropylene (PP) than hydrophilic stainless steel (SSC). A better correlation was established between the biofilms on SSC and PP when analyzed by crystal violet staining than conventional plating method. On comparative evaluation of nutrient rich and diluted growth media, enhanced biofilm formation was observed in latter (1/20 tryptic soya broth). Highest survival in the preformed biofilms was observed at incubation temperature of 25 °C in sterilized skim milk rather than TSB. The present study signify preferable adherence of S. aureus on hydrophobic surfaces and potential survival within preformed biofilm at temperatures prevalent in dairy industries.

Effect of peracetic acid on biofilms formed by Listeria monocytogenes strains isolated from a Brazilian cheese processing plant

“…Pagedar, Singh and Batish (2010) observed that S. aureus cells had higher capacity to form biofilms on polystyrene than stainless steel, suggesting that hydrophobicity was an important factor in the formation of the biofilms, which is in agreement with the differences in the PAA efficiency on polystyrene and stainless steel surfaces as observed in the present study. The survival of L. monocytogenes adhered cells after treatment with PAA at 0.5% (5,000 mg/L), which is nearly ten times over the concentrations normally used in food industries (300 -700 mg/L), indicate the magnitude of risk posed by a potential failure in cleaning and disinfection procedures, including the possibility of L. monocytogenes persistence in the food processing environment.…”

Biocides Resistance Profiles of Biofilm Forming Bacteria of Dairy Niche and their Control

“…Results on efficacy of biocide to control biofilms have been presented in Fig.1. These findings are in agreement with results of Pagedar et al, (2010), who also demonstrated that biofilms were most resistant to sodium hypochlorite and benzalkonium chloride and least to iodophore.…”

A Combined Pharmacodynamic Quantitative and Qualitative Model Reveals the Potent Activity of Daptomycin and Delafloxacin against Staphylococcus aureus Biofilms

“…Biofilms were grown in 96-well plates (European catalog number 734-2327; VWR, Radnor, PA;) with a total volume of 200 l of medium per well and a starting inoculum approximately equal to 10 7 CFU/ml (optical density at 620 nm [OD 620 ] of 0.005). Biofilm production is described as highly dependent on the temperature of the culture medium (20,21). Preliminary experiments showed that a strong biofilm was obtained at 30°C in Bacto tryptic soy broth (TSB; Becton, Dickinson, Franklin Lakes, NJ) supplemented with 0.25% glucose and 0.5% NaCl for the two strains investigated here.…”