Essential oils from fruits with different colors and leaves of Neomitranthes obscura (DC.) N. Silveira: an endemic species from Brazilian Atlantic forest.

Neomitranthes obscura (DC.) N. Silveira is an endemic plant of Brazilian Atlantic Forest and widely spread in the sandbanks of "Restinga de Jurubatiba" National Park. It is popularly known by local population as "camboim-de-cachorro" or "cambuí-preto" and recognized by its black ripe fruits. However, specimens with yellow ripe fruits were localized in the "Restinga de Jurubatiba" National Park. The aim of the present study was to evaluate chemical composition of essential oils obtained from leaves and fruits of N. obscura specimens with different fruit color (black and yellow) by GC and GC-MS. Essential oils from leaves of specimens with black and yellow fruits indicated a predominance of sesquiterpenes (81.1% and 84.8%, resp.). Meanwhile, essential oil from black fruits presented a predominance of monoterpenes (50.5%), while essential oil from yellow fruits had sesquiterpenes (39.9%) as major substances. Despite previous studies about this species, including essential oil extraction, to our knowledge this is the first report on N. obscura fruits with different colors. Our results suggest the occurrence of unless two different varieties for this species.

Triterpene esters and biological activities from edible fruits of Manilkara subsericea (Mart.) Dubard, Sapotaceae.

Manilkara subsericea (Mart.) Dubard (Sapotaceae) is popularly known in Brazil as "guracica." Studies with Manilkara spp indicated the presence of triterpenes, saponins, and flavonoids. Several activities have been attributed to Manilkara spp such as antimicrobial, antiparasitic and antitumoral, which indicates the great biological potential of this genus. In all, 87.19% of the hexanic extract from fruits relative composition were evaluated, in which 72.81% were beta- and alpha-amyrin esters, suggesting that they may be chemical markers for M. subsericea. Hexadecanoic acid, hexadecanoic acid ethyl ester, (E)-9-octadecenoic acid ethyl ester, and octadecanoic acid ethyl ester were also identified. Ethanolic crude extracts from leaves, stems, and hexanic extract from fruits exhibited antimicrobial activity against Staphylococcus aureus ATCC25923. These extracts had high IC50 values against Vero cells, demonstrating weak cytotoxicity. This is the first time, to our knowledge, that beta- and alpha-amyrin caproates and caprylates are described for Manilkara subsericea.