Title:Apoptosis Caused by Triterpenes and Phytosterols and Antioxidant Activity of an Enriched Flavonoid Extract from Passiflora mucronata
Volume: 18
Issue: 10
Author(s): Isabel C.V. da Silva, Goran N. Kaluđerović, Pollyana F. de Oliveira, Denise O. Guimarães, Carla H. Quaresma, Andrea Porzel, Michelle F. Muzitano, Ludger A. Wessjohann and Ivana C.R. Leal*
Affiliation:
- Laboratorio de Produtos Naturais e Ensaios Biologicos, Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Departamento de Produtos Naturais e Alimentos, CCS, Rio de Janeiro, RJ,Brazil
Keywords:
Apoptosis, cytotoxicity, C-glycosilated-flavonoids, pentacyclic triterpenes, phytosteroids, Passiflora mucronata.
Abstract: Background: P. mucronata (Pm) comes from South America, Brazil and is characterized as “Maracujá
de Restinga”. It is used in folk medicine for its soothing properties and in treating insomnia.
Objective: The present study for the first time analyzed the antioxidant and cytotoxicity of the hydroalcoholic
leaves extract and fractions from Pm.
Method: The cytotoxicity test will be evaluated by different assays (MTT and CV) against human prostate cancer
(PC3) and mouse malignant melanoma (B16F10) cell lines, and the antioxidant test by DPPH method.
Results: β-Amyrin, oleanolic acid, β-sitosterol and stigmasterol were isolated of the most active, hexane fraction.
These substances were tested against the tumor cell lines: β-sitosterol and stigmasterol showed the most
relevant activity to PC3 in CV assay and, oleanolic acid to B16F10 by the MTT assay. In addition, it was possible
to indicate that the mode of cell death for stigmasterol, presumably is apoptosis. In terms of antioxidant
activity, the hydroalcoholic leaves extract presented higher activity (EC50 133.3 µg/mL) compared to the flower
(EC50 152.3 µg/mL) and fruit (EC50 207.9 µg/mL) extracts. By the HPLC-MS, it was possible to identify the
presence of flavones in the leaf extract (isoschaftoside, schaftoside, isovitexin, vitexin, isoorientin, orientin).
Conclusions: P. mucronata hexane fraction showed promising cytotoxic effect against cancer cell lines, and
stigmasterol contributes to this activity, inducing apoptosis of these cells. Furthermore, as other Passiflora species,
Pm extract showed antioxidant activity and flavones are its major phenolic compounds.
