Phytochemical Profile and Evaluation of the Allopathic Effect of Three Species of the Genus Cyperus (Cyperaceae)

Abstract

The genus Cyperus is widely distributed worldwide and occurs in various regions of Brazil. Research has reported the allelopathic potential of species belonging to this genus. From this perspective, the present study analyzes the phytochemical profile and allelopathic effect of seven concentrations of the aqueous extracts of Cyperus distans L., Cyperus laxus Lam., and Cyperus rotundus L. The allelopathic potential was evaluated in triplicate from germination bioassays on seeds of two species, Lactuca sativa L. and Emilia fosbergii Nicolson. In addition, phytochemical analyses were performed to analyze possible allelochemicals present in aqueous extracts of three species by phytochemical screening and high-performance liquid chromatography (HPLC). The evaluated variables were: germination (G) and germination speed index (GSI). The data obtained were submitted to the F test, and regression analysis was performed to compare means. The results showed higher susceptibility of E. fosbergii to aqueous extracts of C. distans, C. laxus, and C. rotundus at all concentrations analyzed (0.94, 1.87, 3.75, 7.5, 15, and 30%). In turn, the germination rate of L. sativa seeds decreased only at the highest concentrations (between 15 and 30%) of the same extracts. This allelopathic potential may be directly associated with the biosynthetization of phenolic compounds by Cyperus spp., analyzed in this study by phytochemical prospecting and HPLC.