Antiedema and antinociceptive potential of the essential oil of Pectis elongata Kunt (Asteraceae) from the Brazilian Amazon.

Pectis elongata, a herbaceous species that is known in northern Brazil as "cominho" or "limãozinho", is traditionally used in the region for the treatment of fevers, colds, hypotension, genitourinary and gastric disorders, and pain. Determine the chemical composition and acute oral toxicity and evaluate whether Pectis elongata essential oil (PeEO) has antiedema and antinociceptive activity. The chemical composition was determined using gas chromatography coupled to mass spectrometry (GC/MS) and the degree of toxicity determined by the LD 50. The antiedema and antinociceptive potential was evaluated via the λ-carrageenan-induced paw edema test and formalin test, respectively. Citral (geranial and neral) was characterized as a major component of the PeEO, representing 89% of the total identified compounds. According to OECD criteria (2002), the EO was considered non-toxic since it presented LD 50 values over 2000 mg kg−1. Its antiedema potential was observed at doses of 200 and 400 mg kg−1 (p ≤ 0.05). At a dose of 400 mg kg−1, PeEO also showed antinociceptive potential (p ≤ 0.05), both in the neurogenic phase and in the inflammatory phase. PeEO, which is rich in citral, did not induce any characteristic signs of acute oral toxicity and was also efficient in reducing carrageenan-induced paw edema, in addition to presenting antinociceptive potential and acting on both central and peripheral pain. It is thus a promising candidate for the development of a new herbal medicine with anti-inflammatory and analgesic action. [Display omitted] • Pectis elongata is known in northern Brazil as "cuminho" or "limãozinho". • Its leaves tea is used as antiinflammatory and analgesic in folk medicine. • The essential oil is rich in citral (neral and geranial). • Its oil displayed significant antiedema and antinociceptive activities. • With peripheral and central antinociceptive action. [ABSTRACT FROM AUTHOR]