Abstract

---

Modern and current models such as flow cell technology which enhances a non-destructive growth and inspection of the sessile microbial communities revealed a great understanding of biofilms. A continuous flow system was designed to evaluate possibility of biofilm formation by Escherichia coli DH5a on the stainless steel (type 304) under continuous nutrient supply. The result of the colony iorming unit (CFU) count shows that bacterial attachment and subsequent biofilm formation on stainless steel coupons with average surface roughness of 1.5 ± 1.8 urn and 2.0 ± 0.09 urn were both significantly higher (p < 0.05) than those of the stainless steel coupon with lower surface roughness of 0.38 ±1.5 urn. These observations support the hypothesis that surface profile is one of the factors that influence biofilm formation on stainless steel surfaces. The Scanning electron microscopy and Field emission scanning electron microscopy micrographs of the stainless steel coupons also revealed the attached Escherichia coli DH5a biofilm and dehydrated extracellular polymeric substance on the stainless steel surfaces. Thus the fabricated flow system represented a very useful tool to study biofilm formation under continuous nutrient supply.

Keywords: Biofilm, Coupon, Flow cell, Stainless steel