Phytochemical content of <i>Cannabis sativa</i> methanol extract and in vitro antioxidant activities of its solvent fractions

Abstract

Introduction: In this study, we estimated phytochemical content of Cannabis sativa methanol extract and the antioxidant potentials of the solvent fractions.

Methods: Methanol extract of the plant was screened qualitatively and quantitatively for bioactive phytochemicals. Fractions of the methanol extracts were assayed for antioxidant and lipid peroxidation activities using DPPH, FRAP, SRS and TBA.

Results: Methanol extract contained cardiac glycosides, saponins, flavonoids, alkaloids, tannins, and terpenoids. Methanol fraction (MF) was highly efficacious against ABTS radical (EC₅₀=94.83±0.02μg/mL) in a comparable manner with ascorbic acid (EC₅₀=96.02±0.03μg/mL). The order of efficacy of the fractions on DPPH radical scavenging activity was n-hexane fraction (HF, EC₅₀=78.75±0.08μg/mL) <MF (EC₅₀=120.30±0.04μg/mL) <chloroform fraction (CF, EC₅₀=123.00±0.02μg/mL). Iron chelation activity of CF (EC₅₀=100.00±0.03μg/mL) was close to that of EDTA used as standard (EC₅₀=80.41±0.02μg/mL), followed by MF (EC₅₀=130.7±0.02μg/mL). Close superoxide radical scavenging effect was observed in MF (EC₅₀=95.07±0.01μg/mL) and CF (EC₅₀=94.61±0.05μg/mL).

Conclusion: Conclusively, ME of Cannabis sativa is a rich source of saponins, alkaloids and phenolic compounds. MF was highly effective against ABTS radical, thiobarbituric reactive species, with moderate efficacy on DPPH radical and iron chelation capacity while HF produced higher DPPH and CF has higher iron chelation property.

Key words: C. sativa, ROS, lipid-peroxidation, phytochemistry, antioxidant