Anti‐biofilm and anti‐virulence effects of silica oxide nanoparticle–conjugation of lectin purified from Pseudomonas aeruginosa

Pseudomonas aeruginosa lectin is purified and nanoparticle‐conjugated in an attempt to inhibit biofilm formation. Thirteen (23.6%) P. aeruginosa isolates are obtained from chicken meat samples, of which 30.8% are biofilm producers and 69.2% are lectin producers. Lectin is purified 36.8‐fold to final specific activity of 506.9 U/mg. Four nanoparticle types are prepared via laser ablation: platinum (Pt), gold (Au), silica oxide (SiO 2 ), and tin oxide (SnO 2 ). The four types are characterised, and pulse feeding is used to conjugate the lectin and nanoparticles. Pt, Au, SiO 2, and SnO 2 nanoparticles inhibit biofilm formation, especially SiO 2 nanoparticles, which have higher effectiveness when conjugated with purified lectin. SiO 2 ‐conjugated lectin significantly ( p  < 0.05) inhibits biofilm formation more effectively than control and other nanoparticle‐conjugated lectins. Au‐, Pt nanoparticle‐, and SnO 2 ‐conjugated lectins inhibit biofilm significantly compared with control ( p  < 0.05), and rhlR gene expression is decreased in the presence of SiO 2 ‐conjugated lectin. Furthermore, lectin and Pt, Au, SiO 2 and SnO 2 nanoparticles separately, and their conjugated lectins, are effective biofilm inhibitors. Of these, SiO 2 ‐conjugated lectin was most significant as an anti‐biofilm. Moreover, virulence factors regulon and RhlR were reduced by SiO 2 ‐conjugated lectin, indicating that this conjugation may also decrease the virulence of P. aeruginosa .