Mitigation of microbiologically influenced corrosion of 304L stainless steel in the presence of Pseudomonas aeruginosa by Cistus ladanifer leaves extract

Abstract In this study, the efficiency of Cistus ladanifer ethanolic extract to inhibit the corrosion of 304L stainless steel (SS) in the presence of Pseudomonas aeruginosa was evaluated using electrochemical measurements and surface analysis techniques. The plant extract was characterized by HPLC-Q-TOF-MS. Furthermore, the effect of this extract on the physicochemical properties of 304L SS coupon surfaces was determined by contact angle measurements. The obtained results indicated that P. aeruginosa formed biofilms on the 304L SS coupon surfaces which led to the acceleration of corrosion rate and damage of the surface in form of pitting corrosion with a maximum pit depth of 19.4 μm. Moreover, C. ladanifer extract inhibited the growth of P. aeruginosa planktonic cells and the biofilm formation on the 304L SS coupon surfaces. Also, the extract reduced the biocorrosion rate by approximately 99.36%. Many well-known antimicrobial and anti-corrosion compounds present in the extract were characterized, such as flavonoids, tannins, and phenolic acids, supporting the excellent anti-biofilm and anti-corrosion performances of C. ladanifer extract.