Effect of trans-Resveratrol and Ascorbigens on the Fire Blight Pathogen Erwinia amylovora in the BioArena System

On the basis of our earlier observations, preliminary experiments were conducted with the fire blight pathogen Erwinia amylovora with the BioArena system using the potential antibacterial substances 1'-methylascorbigen (MeAG) as formaldehyde (HCHO) precursor and trans-resveratrol (RES) as HCHO mobilizer, capturer, and scavenger. Results showed characteristic, strong, dose-dependent antibacterial effects of both MeAG and RES present as chromatographic spots on the adsorbent layer. It is supposed that the weak antibacterial effect of AG may have originated from MeAG formed in situ on the layer by partial enzymatic methylation of AG. Addition of HCHO capture compounds (L-arginine, glutathione, glucosamine) to the culture medium before inoculation partially or totally reduced the antibacterial effect of both molecules, that is, this simplest aliphatic aldehyde, the endogenous HCHO molecule, participates in the antibacterial activity of these compounds. It follows from these results that there is a possibility of interaction between endogenous H2O2 and HCHO in the chromatographic spots and it is supposed that these reactive molecules and potential derivatives, e.g. singlet oxygen (O-1(2)) and ozone (O-3), may be the causes of the destructive effect of the fire blight pathogen on fruit trees.