Rhamnolipid Coating Reduces Microbial Biofilm Formation on Titanium Implants: an in-vitro Study

Abstract

Background: Peri-implant mucositis and peri-implantitis are biofilm-related diseases causing major concern in oral implantology, requiring complex anti-infective procedures or implant removal. Microbial biosurfactants emerged as new of anti-biofilm agents for coating implantable devices preserving biocompatibility. This study aimed to assess the efficacy of rhamnolipid biosurfactant R89 (R89BS) to reduce Staphylococcus aureus and Staphylococcus epidermidis biofilm formation on titanium. Methods: R89BS was physically adsorbed on titanium discs (TDs) and the ability of coated TDs to inhibit biofilm formation was evaluated by quantifying biofilm biomass and cell metabolic activity, at different time-points, with respect to uncoated controls. A qualitative analysis of sessile cells was also performed by scanning electron microscopy. Results: R89BS-coated discs showed no cytotoxic effects on normal lung fibroblasts (MRC5). TDs coated with 4 mg/mL R89BS inhibited the biofilm biomass of S. aureus by 98%, 49% and 10% and of S. epidermidis by 53%, 29%, and 10% at 24, 48 and 72 h respectively. A significant reduction of the biofilm metabolic activity was also documented. The same coating applied on three commercial implant surfaces resulted in a biomass inhibition higher than 90% for S. aureus, and up to 75% for S. epidermidis at 24 h. Conclusions: R89BS-coating was effective in reducing Staphylococcus biofilm formation at the titanium implant surface. The anti-biofilm action can be obtained on several different commercially available implant surfaces, independently of their surface morphology.

Antibiofilm effect of mono‐rhamnolipids and di‐rhamnolipids on carbon steel submitted to oil produced water

“…Wood et al proved the rhamnolipid actions against sulfate‐reducing bacteria biofilm since RML are the biochemical basis of biofilm dispersal and antiadhesion 2 . More recently, Tambone and coauthors reported that rhamnolipids decrease biofilm formation on titanium implants 35 . Additionally, various chemical surfactants have biocidal properties 3 .…”

“…2 More recently, Tambone and coauthors reported that rhamnolipids decrease biofilm formation on titanium implants. 35 Additionally, various chemical surfactants have biocidal properties. 3 In the present study was shown clearly that the RML (with highlight for mono-RML) was able to prevent biofilm formation more effectively than one of the most popular surfactants used in the oil industry-SDS.…”

Synthetic and biological surfactant effects on freshwater biofilm community composition and metabolic activity

“…When exposing single-cell biofilms of P. aeruginosa to rhamnolipids, growth and development were disrupted, and cell viability was reduced (De Rienzo et al ., 2015). Disruptions by rhamnolipids have also been shown for single species biofilms of Staphylococcus aureus (Quinn et al ., 2013; Aleksic et al ., 2017; Tambone et al ., 2021), Bacillus pumilus (Dusane et al ., 2010), and Rhodococcus erythropolis (Schreiberova et al ., 2012). Yet, rhamnolipids are biodegradable in a variety of environments, including under aerobic and anaerobic conditions (Mohan et al ., 2006; Ramos da Silva et al ., 2019).…”