In vitro antioxidant potentials of Cyperus rotundus L. rhizome extracts and their phytochemical analysis

Background: Cyperus rotundus L. (family Cyperaceae), native to India, is a multivalent medicinal plant widely used in conventional medicine. The research reports on bioactive components from C. rotundus L. are scanty. Objective: The objective of the study was to optimize the best solvent system and bioprospect the possible phytochemicals in C. rotundus L. rhizome (CRR). Materials and Methods: The phytochemicals were extracted from the rhizomes of C. rotundus L. by successive Soxhlet technique with solvents of increasing polarity. The resultant extracts were analyzed for their total flavonoid content (TFC), total phenolic content (TPC), total proanthocyanidin content (TPAC), in vitro antioxidant potential, and inhibition of lipid peroxidation. The 70% acetone extract of CRR was analyzed using gas chromatography-mass spectrometry (GC-MS) for probable phytochemicals. Results and Discussion: The TPC, TFC, and TPAC estimates ranged from 0.036 ± 0.002 to 118.924 ± 5.946 μg/mg extract, 7.196 ± 0.359 to 200.654 ± 10.032 μg/mg extract, and 13.115 ± 0.656 to 45.901 ± 2.295 μg/mg extract, respectively. The quantities of TPC, TFC, and TPAC were found to be the highest in 70% acetone extract. The 70% acetone and 70% methanol extracts revealed best radical scavenging effect. GC-MS analysis of CRR extract revealed the presence of a novel compound 1 (2)-acetyl-3 (5)-styryl-5 (3)-methylthiopyrazole. Conclusion: The study indicated that 70% acetone and 70% methanol extracts of CRRs can be a potential source of antioxidants. Abbreviations used: ACRE: Acetone C. rotundus L. rhizome extract; AlCl3: Aluminum chloride; AQRE: Aqueous C. rotundus L. rhizome extract; CE: Catechin Equivalent; CHRE: Chloroform C. rotundus L. rhizome extract; CRR: C. rotundus L. rhizome; DPPH: 2,2 diphenyl-1-picrylhydrazyl; ETRE: Ethanolic C. rotundus L.rhizome extract; EARE: Ethyl acetate C. rotundus L.rhizome extract; FRP: Ferric reducing power; GAE: Gallic acid equivalent; GC-MS: Gas chromatography-mass spectrometry; HERE: Hexane C. rotundus L.rhizome extract; MERE: Methanolic C. rotundus L.rhizome extract; PERE: Petroleum ether C. rotundus L.rhizome extract; QE: Quercetin equivalent; RNS: Reactive nitrogen species; ROS: Reactive oxygen species; TFC: Total flavonoid content; TPC: Total phenolic content; TPAC: Total proanthocyanidin content.