RAPISARDA Viviana Andrea
congresos y reuniones científicas
ANTIFUNGAL ACTIVITY OF POLYHEXAMETHYLENE GUANIDINE HYDROCHLORIDE AGAINST PENICILLIUM DIGITATUM
OLMEDO, G. M.; CERIONI, L.; RAMALLO, J.; RAPISARDA, V. A.; VOLENTINI, S. I.
Congreso; International Citrus Congress 2016; 2016
P. digitatum is the green mold causal agent in citrus fruit during postharvest. To control this pathogen, lemons are treated with fungicides leading to the proliferation of resistant strains and the increase of toxic residues on fruit. International markets have implemented strict limits on such residues. Thus, finding alternative methods for decay control is critical. Polyhexamethylene guanidine hydrochloride (PHMG) is an active principle of a new generation disinfectant. Here, its in vitro inhibitory action against P. digitatum was tested in 24h-incubations. Conidia germination in potato dextrose broth (PDB) was inhibited in the presence of 1 ppm PHMG with complete loss of viability as revealed by CFU/mL counts. When PHMG was added to 24-h germinated conidia, mycelial growth was inhibited by 10 ppm PHMG and sporulation process was suppressed with 1 ppm. Sytox Green dye was broadly incorporated in conidia exposed to PHMG, indicating loss of membrane integrity. In addition, ultrastructural changes in conidia were analyzed by TEM, revealing severe cellular damage after treatment. Even though further assays are necessary, these findings suggest that PHMG has outstanding antifungal properties which could lead to its potential application in packing houses to improve postharvest disease control.