Medicinal plant extracts and nematode control.

Abstract

Abstract Several aspects should be taken into consideration in relation to the use of active botanical extracts or compounds in parasite control: extraction, conservation, phytochemical study, determination of lethal concentration in vitro , toxicity to the host, effective dose in vivo , residual period, stability, residues/metabolites generated and costs. The in vitro tests that have been used to screen biological activity were developed to detect parasite resistance to anthelmintics. In this way, the effects of a potent plant extract can be underestimated or dismissed if the selected methods disregard some factors that can influence the results, such as solubility or an indirect effect on the nematode. Despite this, the development of strategies that are less dependent on in vivo testing is important. There is a need for fuller investigations not restricted only to indicating whether or not a phytotherapy was effective against parasites. The divergence between efficacy in vitro and inefficacy in vivo can be attributed to key factors related to bioavailability as well as pharmacology of the botanical substances in the host organism. It is important to focus studies to determinate the most appropriate adjuvants and to develop formulation models that can be adapted according to the nature of the plant extract or bioactive compound isolated, to serve as starting points for the development of semi-synthetic and synthetic substances.