RESUMO
Leishmaniasis is one of the most neglected tropical diseases, representing a group of parasitic diseases worldwide spread, occurring in 88 tropical and subtropical countries. Approximately 350 million people live in areas of active transmission of leishmaniasis, with about 1-2 million estimated new cases occurring every year. More than 90 percent of the cutaneous cases appear in developing countries. Efforts to improve the therapeutic arsenal against leishmaniasis have led to the search for new and cheap range of drugs. In this study, the nerolidol-rich essential oil from Piper claussenianum (Miq.) C. DC., Piperaceae, was assayed on arginase activity of Leishmania amazonensis. The effect of this essential oil on arginase activity levels showed an enzyme inhibition of 62.2 percent. This result stimulates the scientific interest about the potential value of this plant species on neglected diseases as potential new natural product source of pharmacological interest for the treatment of leishmaniasis.
RESUMO
Analyses of essential oils obtained from fresh and dried leaves and inflorescences of Piper clausenianum were performed using GC-FID, GC-MS and NMR techniques. Forty compounds were detected for these four oils with the total of identified constituents ranging from 88.7% for the dried inflorescences to 97.7% for the dried leaves. Sesquiterpenes were the main constituents in the volatile fraction from leaves with a high percentage of (E)-nerolidol (up to 83%). However, monoterpenes were identified in greater amount in the inflorescences, with linalool percentages from 50% up. The essential oils from fresh leaves and inflorescences were submitted to anti-parasitic activity against a strain of Leishmania amazonensis. Both samples showed biological activity, but the essential oil from P. claussenianum fresh leaves, which was rich in (E)-nerolidol, showed effective growth inhibition of L. amazonensis due to the high percentage of this metabolite in the mixture.