TOTAL PHENOLIC CONTENT, ANTIOXIDANT AND ANTICANCER ACTIVITIES OF FOUR SPECIES OF SENNA Mill. FROM NORTHEAST BRAZIL

Objective: The present investigation evaluated the antioxidant and anticancer properties and total phenolic contents of four species of Senna: S. gardneri, S. macranthera, S. splendida and S. trachypus from northeast Brazil. Methods: Ethanolic extracts of leaves and roots of the four Senna species were screened for phytochemical procedures. An in-vitro antioxidant study was conducted by means of DPPH and ABTS radical scavenging assays. Anticancer activity was evaluated using the MTT 3-(4,5-dimethylthiazole-2-yl)-2,5- diphenyltetrazolium bromide) method against the HCT-116, SF-295 and OVCAR-8 cancer cell lines. Total phenolic contents were determined using a Folin-Ciocalteau colorimetric assay. Results: Anthraquinones, flavonoids, phenolics, steroids, tannins, triterpenoids, xanthones, and glycosides were detected in all Senna extracts. The results for the antioxidant activity showed that the highest percentage of scavenger radicals was present in the extract from roots of Senna trachypus (StR), which showed higher levels than the two standards used. The highest percentage of inhibition of the cancer cell lines tested was obtained with the leaf extracts of S. gardneri (SgL) and S. splendida (SsL). Conclusion: The ethanolic extracts of the four species of Senna showed antioxidant activity in both assays, and this activity can be attributed to the presence of phenolic compounds such as flavonoids and anthraquinones. S. trachypus showed a higher antioxidant potential than the standards, as well as a higher total phenolic content. Only two of the plants showed promising results for anticancer activity