Phytochemical Analysis and Evaluation of the Antioxidant Activity of Cedrus atlantica (Endl.) G. Manetti ex Carrière Stem Extracts
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Abstract
Cedrus atlantica is a Mediterranean medicinal plant used to treat a number of ailments including cancer and urinary tract infections. This study is aimed to analyze the phytochemical constituents and evaluates the antioxidant activity of Cedrus atlantica stem extracts. Powdered stem of Cedrus atlantica underwent successive extraction with cyclohexane, ethyl acetate, and ethanol using Soxhlet apparatus to obtain cyclohexane (F1), ethyl acetate (F2), and ethanol (F3) extracts. The marc was macerated with water to obtain the aqueous extract (F4). Phytochemical screening was performed following standard procedures. Total phenolic, flavonoid, flavonol, and tannin contents were also determined. The extracts were subjected to gas chromatography mass spectrometry analysis. The antioxidant activity was evaluated using the DPPH, ABTS, FRAP and TAC assays. Phytochemical screening revealed the presence of flavonoids, anthocyanins, tannins, quinines, coumarins, terpenoids, anthraquinones, sterols, and saponins in the plant. F3 showed the highest content of total polyphenols (237.23±1.61 mgGAE/g extract) and tannins (189.4±0.76 mgCE/g extract), while F2 exhibited the highest content of total flavonoids (81.53±1.13 mgQE/g extract) and flavonols (33.4±0.16 mgQE/g extract). F3 also demonstrated the most potent antioxidant efficacy in the DPPH (IC50 = 19.40±0.01 μg/mL), ABTS (IC50 = 21.24±0.002 μg/mL), FRAP (EC50 = 94.36±2.51 μg/mL), and TAC (780.97±4.86 µg AAE/g extract) assays. GC-MS analysis identified acids, phenolic compounds, terpenes, and steroids in the extracts, suggesting their contribution to the antioxidant activity exhibited by the plant extracts. These observations underscore the therapeutic potential of the plant and justify its traditional medicinal application across various diseases.
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