CITOTOXICIDAD DE UNA ASPARTIL PEPTIDASA DE Salpichroa origanifolia FRENTE A LA INFECCIÓN CAUSADA POR Phytophthora capsici EN ZAPALLITOS VERDES (Cucurbita maxima, var. Zapallito)

Phytophthora capsici is a phytopathogenic agent that causes significant losses in crops of economic interest. The chemicals traditionally used to fight these pathogens cause adverse effects on health and the environment. Native plants represent an alternative source of natural antifungal metabolites. In our laboratory we have studied a perennial herb, Salpichroa origanifolia, native to the northern and central Argentina whose ovoid fruits are edible berry. An aspartyl peptidase from the crude extract of the ripe fruit of this species was purified by ion exchange chromatography using a batch process. The enzyme was called salpichroin. In this work the antifungal effect of the aspartyl peptidase on P. capsici was studied. It was obtained that salpichroin had a high cytotoxic effect in vitro on strains of P. capsici (MIC: 1.2 μmol L-1). To evaluate the enzyme effect on the development of P. capsici in vivo, inoculation controlled bioassays on green zucchini (Cucurbita maximum var Zapallito) were performed. The fruit inoculated with the phytopathogen and salpichroin remained asymptomatic for seven days.