Effect of the hexane extract of Achyrocline satureioides on the growth, production of proteases and spore germination of Paenibacillus larvae

PIMENTEL BETANCURT, DIANA C.; PALETTI ROVEY, M. FERNANDA; CASSINA, CAROLINA; BEOLETTO, VIVIANA; OLIVA, M. DE LAS MERCEDES; MARIOLI, J. MIGUEL

Congreso; 7th International Conference on Microbial Communication for Young Scientists; 2018

Paenibacilluslarvae, Grampositive bacillus that affects the larval stage of honey bees, causes thedisease known as American Foulbrood (AFB). It is a highly destructive andnotifiable disease, which has a negative impact on beekeeping, agriculture andfood security. The spores of the pathogen reach the larva through contaminatedfood provided by the nurse bees, reaching the lumen of the larval intestine,where they germinate and the vegetative cell proliferates massively destroyingthe peritrophic membrane and the cell-cell junctions until the death of thelarva. During infection, P. larvae secretes proteases that could beinvolved in pathogenicity. For the control of the ABF, antibiotics such asoxytetracycline hydrochloride (OTC) were used to act effectively on thebacterial form, but not on the infectious spore, masking the disease byreducing the symptoms, without completely eradicating it, also generatingbacterial resistance and residues of these chemicals in honey. The plantextracts are proposed as an ecological, viable and acceptable alternative forthe treatment of the disease in the hives. Achyrocline satureioides is aplant native to southeastern South America, widely used due to itspharmacological and antibacterial properties.