Artocarpus integrifolia seed lectin enhances membrane damage, oxidative stress and biofilm inhibition activity of silver nanoparticles against Staphylococcus aureus

Functionalizing the nanoparticles to target the bacteria surface is an effective approach to curb drug resistance pathogens. The present study describes the synthesis of N-myristoyltaurine capped silver nanoparticles (AgNPs) and functionalization of AgNPs with jacalin (JAgNPs), a lectin from the seeds of Artocarpus integrifolia. JAgNPs has fourfold lower minimum inhibitory concentration than AgNPs and kills the S. aureus in less than 30 min through inducing oxidative stress and membrane damage. JAgNPs (31.25 mu M) was found to have excellent biofilm inhibitory activity at lower concentration than AgNPs (62.5 mu M). This was judged by crystal violet assay, light microscopy imaging and confocal laser scanning microscopy (CLSM) method. CLSM analysis reveals that JAgNPs is highly effective as compared to AgNPs in reducing the bio-volume and average biofilm thickness to 18.3 +/- 2.5 mu m3/mu m2 and 14.0 +/- 2.6 mu m, respectively. Scanning electron microscopy (SEM) study reveals that JAgNPs prevents the colony formation and inhibited exopolysaccharide synthesis, thereby reducing the formation of biofilm. At minimum biofilm inhibitory concentrations, SEM and double staining technique using CLSM provides evidence that cells are intact and live, suggesting that NPs exhibit true biofilm activity. The findings indicate that jacalin functionalization may offer a unique way to use nanosilver at lower concentrations for treating infection associated with S. aureus biofilm.

Automated summary

Functionalizing nanoparticles to target bacteria surfaces is an effective approach to combat drug-resistant pathogens. This study synthesized N-myristoyltaurine capped silver nanoparticles (AgNPs) and functionalized them with jacalin from Artocarpus integrifolia seeds. The functionalized AgNPs (JAgNPs) had a lower minimum inhibitory concentration and showed superior biofilm inhibition activity against S. aureus compared to AgNPs, suggesting a unique way to use nanosilver for treating infections associated with S. aureus biofilm.