Antioxidants from fruits and leaves of Eugenia jambolana, an edible Myrtaceae species from Atlantic Forest

Eugenia jambolana Lam. belongs to Myrtaceae, a plant family widespread in Brazil, known for its edible fruits as guava (Psidium guajava L.), jambo (Syzygium jambos (L.) Alston), araçá-rosa (Psidium cattleianum Sabine), pineapple guava (Feijoa sellowiana Berg.), pitanga (Eugenia uniflora L.), grumixama (Eugenia brasiliensis Lam.), scrub cherry (Syzygium australe (Link.) B. Hyland), most of which present astringent properties due to their tannin content. There are few phytochemical studies on such species, although preliminary evaluation of some Myrtaceae edible fruits has evidenced high contents in vitamin C and phenolic compounds. Additionally, the extract from seeds of E. jambolana has been used as traditional medicine in India, Brazil and other tropical countries for its hypoglycemic and antidiabetic properties, which have been associated with its antioxidant and anti-inflammatory activities. As part of our studies on species from Tropical Rain Forest (Atlantic Forest), fruits and leaves of Eugenia jambolana were collected and their ethanol extracts showed positive results when screened for antioxidant (bleaching of beta-carotene TLC autographic assay [1]) and cytotoxic (MTT assay for MDA/MB-435, SF-295 and HCT-8 cell lines [2]) activities. Phytochemical work on the EtOH fraction led to the isolation of polyphenols, including flavonoid glycosides and phenolic acids from the leaves, and anthocyanins cyanidin and delphinidin glycosides from the fruits extract. The isolates were submitted to evaluation of their antioxidant properties and showed strong free radical scavenging activity towards DPPH. These results support the use of extracts of E. jambolana in traditional medicine and suggest their actions as possible chemopreventive agents or phytoceuticals.

Acknowledgements: This work was sponsored by the program BIOTA-FAPESP, BioProspecTa, CAPES and CNPq.

References: 1. Pratt, D. E., Miller, E. E. (1984), J. Am. Oil Chem. Soc. 61: 1064–1067. 2. Skehan, P., Storeng, R. et al. (1990), J. Natl. Cancer Inst. 82: 1107–1112.