Variation in essential oil components and anti-inflammatory activity of Allophylus edulis leaves collected in central-western Brazil

Ethnopharmacological relevance: An infusion obtained from the leaves of chal-chal (Allophylus edulis Radlk.) is used for popular treatment of intestinal disorders and as an anti-inflammatory throat treatment. Because of the anti-inflammatory medicinal folk use, a previous work reported scientific research confirming the antiinflammatory activity of A. edulis essential oil collected in Dourados, MS, Brazil, in March 2015. Aim of the study: The aim of this study was to evaluate the variation in the chemical profile of the essential oil of A. edulis plants collected in Dourados (EOAE-D) and Bonito (EOAE-B), two cities in Mato Grosso do Sul State, Brazil. Additionally, we evaluated the anti-inflammatory effects of the essential oil, as well as that of the major compounds (caryophyllene oxide and alpha-zingiberene), in experimental in vivo models of inflammation in mice. Materials and methods: Leaves were collected from plants at both sites in July 2018. The composition of the essential oil (EOAE-D and EOAE-B) was determined by GC/MS, and major compounds (caryophyllene oxide and alpha-zingiberene) were isolated and identified by chromatographic methods and NMR spectroscopy. Anti-inflammatory capacities were assessed using two classical models of inflammatory models, carrageenan- and CFA-induced paw inflammation (mechanical and thermal hyperalgesia). Results: Both EOAE-D and EOAE-B showed sesquiterpenes as a major constituent, namely, caryophyllene oxide (29.5%) and alpha-zingiberene (45.0%), respectively. In tests, EOAE, caryophyllene oxide and alpha-zingiberene-induced antiedematogenic and antihyperalgesic effects were found in the different utilized models. Conclusions: The results indicate that samples from the two cities differed in chemical composition but not in their anti-inflammatory and antihyperalgesic effects. This finding corroborates the use of A. edulis as a medicinal plant and indicates its potential in the therapy of inflammatory conditions.

Automated summary

The study aimed to evaluate the variation in the chemical profile of the essential oil of A. edulis plants collected in two cities in Mato Grosso do Sul State, Brazil, and assess the anti-inflammatory effects of the essential oil and its major compounds in experimental in vivo models of inflammation in mice. The results showed that samples from the two cities differed in chemical composition but had similar anti-inflammatory effects, indicating the potential therapeutic use of A. edulis in inflammatory conditions.