Chemical composition, antioxidant and antibacterial activity of Adiantum capillus-veneris L. extract from Algeria

Abstract

The present study evaluates the antioxidant and antibacterial activities as well as the chemical composition of the aerial part of Adiantum capillus-veneris L., which are endemic to the flora of Algeria. The total phenolic amount of the hydromethanolic extract, as measured by the Folin-Ciocalteu reagent procedure, was found to be about 23.44 ± 0.14 mg GAE/g DW, while the flavonoid content value was 4.66 ± 0.01 mg CE/g DW, as measured by aluminum chloride colorimetric method. The antioxidant power of the extract was analyzed using the DPPH method. DPPH radicals were scavenged with an IC50 value of 65.85 µg/mL. The antibacterial activity of hydromethanolic extract against five bacterial strains of Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 25853), Staphylococcus aureus (ATCC 25923), Streptococcus pneumoniae and Bacillus cereus (ATCC 10876) were carried out using the disc diffusion test and the microdilution method. Streptococcus pneumoniae is the most sensitive bacterium with inhibition zone of 9.0 ± 1.1 cm and MIC=10 mg/mL. Based on HPLC analysis, we find that quercetin 3-O-glucoside was the most abundant compound in the plant extract. This study demonstrates that Adiantum capillus-veneris could be a potential natural source of antibacterial and antioxidant compounds.