Assessment of the In Vitro Antischistosomal Activities of the Extracts and Compounds from Solidago Microglossa DC (Asteraceae) and Aristolochia Cymbifera Mart. & Zucc. (Aristolochiaceae).

Schistosomiasis, caused by helminth flatworms of the genus , is a neglected tropical disease that afflicts over 230 million people worldwide. Currently, treatment is achieved with only one drug, praziquantel (PZQ). In this regard, the roots of (Asteraceae) and (Aristolochiaceae) are popularly used as anthelmintic. Despite their medicinal use against helminthiasis, such as schistosomiasis, . , and . have not been evaluated against . . Then, in this work, the in vitro antischistosomal activity of the crude extracts of . (Ac) and . (Sm) and their isolated compounds were investigated against . adult worms. Sm (200 g/mL) and Ac (100-200 g/mL) were lethal to all male and female worms at the 24 h incubation. In addition, Sm (10-50 g/mL) and Ac (10 g/mL) caused significant reduction in the parasite's movements, showing no significant cytotoxicity to Vero cells at the same range of schistosomicidal concentrations. Confocal laser scanning microscopy revealed that Sm and Ac caused tegumental damages and reduced the numbers of tubercles of male schistosomes. Chromatographic fractionation of Sm leads to isolation of bauerenol, -amirin, and spinasterol, while populifolic acid, cubebin, 2-oxopopulifolic acid methyl ester, and 2-oxopopulifolic acid were isolated from Ac. At concentrations of 25-100 M, bauerenol, -amirin, spinasterol, populifolic acid, and cubebin showed significant impact on motor activity of . . 2-oxopopulifolic acid methyl ester and 2-oxopopulifolic acid caused 100% mortality and decreased the motor activity of adult schistosomes at 100 M. This study has reported, for the first time, the in vitro antischistosomal effects of . and . extracts, also showing promising compounds against adult schistosomes.