Chemical Composition and Antioxidant Activity of Extracts from the Inner Bark of Berberis vulgaris Stem

Extracts from the inner stem bark of Berberis vulgaris were analyzed for their antioxidant activity using the 1,1-dipheny-2-picrylhydrazyl (DPPH) method and compared with ascorbic acid (AA) and butylated hydroxytoluene (BHT). The most active extracts were analyzed for their chemical composition using gas chromatography-mass spectrometry. Acetone extract was found to be the most active as an antioxidant agent at 98.61%, which was higher than the value of vitamin C (93.03%) at the concentration of 0.16 mg/mL. The major components identified in the acetone extract were tetracosanoic acid, methyl ester (26.36%), followed by phthalic acid, diisooctyl ester (20.93%), 1,2-bis(trimethylsiloxy) ethane (10.26%), and 1,2-benzendicarboxylic acid, diisononyl ester (8.70%). The dissolved water:methanol (1:1 v/v) partitioned from acetone extract afforded 12 fractions; among them, fraction F11 was found to have good antioxidant activity (95.41%) at the concentration of 0.16 mg/mL. The major compounds identified in F11 were N-methyl-4-(hydroxybenzyl)-1,2,3,4-tetrahydroisoquinoloine (28.82%), 9-α-hydroxy-17β-(trimethylsilyl-oxy)-4-anderostene-3-methyloxime (13.97%), ribitol, pentaacetate (9.76%), 1-methyl-4-[4,5-dihydroxyphenyl]-hexahydropyridine (6.83%), and 2-ethylacridine (4.77%)