Melittin based on silica nanoparticles for Agrobacterium tumefaciens inhibition

An effective method for Agrobacterium tumefaciens inhibition using silica nanoparticles (NPs) as the carrier and melittin as the antibacterial drug is developed. The diameters of the inhibition zones of A. tumefaciens treated with different concentrations of melittin-conjugated silica NPs, pure silica NPs, gentamicin and free melittin are determined. The results indicate that the pure silica NPs have no impact on A. tumefaciens. The melittin-conjugated silica NPs have strong antibacterial activity against A. tumefaciens. In addition, the antibacterial activity of the melittin-conjugated silica NPs is dose dependent. The diameter of the inhibition zone caused by the melittin-conjugated silica NPs is almost the same as the positive control. Compared with the free drug molecules, silica NPs as an ideal carrier can gather a large number of drug molecules on their surface so as to greatly enhance the antibacterial activity.