Effects of Flavonoids and Phenols from Leaf Extracts on Biofilm Processes in Pv.

pv. is the causal agent of black rot in crucifers, a plant disease with significant economic impact. Xanthomonadaceae is a large family of Gram-negative bacteria that cause symptoms by blocking water flow in plants by invading the xylem. To accomplish this, the main mechanism the bacteria use to adapt to environmental changes and colonize tissues is biofilm formation. In recent years, growing interest in natural antimicrobial compounds has led to the study of different phytocomplexes derived from plants. In this work, was selected, as its leaves are rich in phenols, essential oils, and vitamins that exert antibacterial activity. pv. biofilm, one of its major virulence factors, was studied. Biofilm formation and removal were analyzed on abiotic and biotic surfaces with and without leaf extracts. The data from the analysis show that leaf extracts and single phenols were able to inhibit biofilm growth on abiotic surfaces, but the activity of the whole phytocomplex was significantly higher compared to that of individual phenols. The effect of extracts on cabbage leaves in vivo was also found to be very important, as scanning electron microscopy showed that treatment with the extracts led to clear unblocking of the xylem, implying many advantages for use in black rot control.