Many researchers have focused on the investigation of natural
products as the source of new bioactive molecules because
of failure of available antimicrobials to treat infectious diseases.
Natural products of vegetable origin can alter the effect
of antibiotics, be it increasing or reducing the antibiotic activity
(Coutinho et al., 2008). The association between natural
products and synthetic drugs has been studied in several works
and the results are relevant and promising (Matias et al., 2011;
Rodrigues et al., 2010; Coutinho et al., 2008).