Phytochemical characterization, isolation, antioxidant and cytogenotoxic activity of leaves of Heliotropium elongatum (Lehm) I.M. Johnst

Abstract

ABSTRACT Heliotropium elongatum is used to treat inflammation, cough, and flu. This study aimed to characterize the phytochemical profile and determine the total phenolic content (TPC), antioxidant and cytogenotoxic activity of the ethanolic extract (EE), and fractions of H. elongatum leaves. In the phytochemical profile analysis, organic acids, reducing sugars, flavonoids, saponins, anthraquinones, steroids/triterpenes, and depsides/depsidones were detected in the EE and/or fractions (hexanic/FH, chloroformic/FC, ethyl acetate/FAE, and hydromethanolic/FHM). The highest TPC and highest antioxidant activity (DPPH and ABTS) was detected in FHM. In FH, 16 compounds were identified by GC-MS, and ursolic acid was isolated by 1H NMR and 13C NMR. HPLC-DAD from EE, FAE, and FHM demonstrated characteristic wavelengths for flavonoids, flavonols, flavones, and anthraquinones. ESI-IT/MSn analysis of EE, FC, FAE, and FHM revealed alkaloids, steroids, terpenoids, flavonoids, and phenolic acids. In Allium cepa assay there was no significant cytotoxic effect initiated by EE (62.5 to 1,000 µg/ml), FHM (1,000 µg/ml), and FAE (62.5 µg/ml). Genotoxicity was evidenced only with EE at 500 and 1,000 µg/ml, and FHM (62.5 to 1,000 µg/ml) as evidenced by presence of micronuclei (MN) and nuclear buds (NB). Our results identified compounds of medicinal interest with antioxidant activity; however observed cytogenotoxic changes indicated the need for caution when using these compounds for therapeutic purposes.