Phytochemical Profile, Preliminary Toxicity, and Antioxidant Capacity of the Essential Oils of Myrciaria floribunda (H. West ex Willd.) O. Berg. and Myrcia sylvatica (G. Mey) DC. (Myrtaceae)

The essential oils (EOs) of Myrciaria floribunda (Mflo) and Myrcia sylvatica (Msyl) (Myrtaceae) were obtained by hydrodistillation. The analysis of volatile constituents was performed by GC/MS. Preliminary toxicity was assessed on Artemia salina Leach. The antioxidant capacity was measured by the ABTS(center dot+) and DPPH center dot radical inhibitory activities. The results indicate that the Mflo EO had the highest yield (1.02%), and its chemical profile was characterized by high levels of hydrocarbon (65.83%) and oxygenated (25.74%) monoterpenes, especially 1,8-cineole (23.30%), terpinolene (22.23%) and alpha-phellandrene (22.19%). Regarding the Msyl EO, only hydrocarbon (51.60%) and oxygenated (46.52%) sesquiterpenes were identified in the sample, with (Z)-alpha-trans-bergamotene (24.57%), alpha-sinensal (13.44%), and (Z)-alpha-bisabolene (8.33%) at higher levels. The EO of Mflo exhibited moderate toxicity against A. salina (LC50 = 82.96 +/- 5.20 mu g.mL(-1)), while the EO of Msyl was classified as highly toxic (LC50 = 2.74 +/- 0.50 mu g.mL(-1)). In addition, relative to Trolox, the EOs of Mflo and Msyl showed significant inhibitory effects (p < 0.0001) against the DPPH center dot radical. This study contributes to the expansion of chemical and biological knowledge on the EOs of Myrtaceae species from the Amazon region.

Automated summary

This study analyzed the essential oils of Myrciaria floribunda and Myrcia sylvatica obtained by hydrodistillation and assessed their toxicity and antioxidant capacity. The results showed that Myrciaria floribunda essential oil contained high levels of hydrocarbon and oxygenated monoterpenes, while Myrcia sylvatica essential oil contained hydrocarbon and oxygenated sesquiterpenes. Myrciaria floribunda essential oil exhibited moderate toxicity against Artemia salina, while Myrcia sylvatica essential oil was highly toxic. Additionally, both essential oils showed significant inhibitory effects against the DPPH radical.