Phenolic constituents, antioxidant and antimicrobial activities of methanolic extracts of some female cones of gymnosperm plant

Abstract

In the present study, the total antioxidant activity, the total phenolic content, and the antimicrobial activity of methanol extracts obtained from the female cones of Pinus brutia, Pinus nigra, Cupressus sempervirens L., Thuja orientalis L., and Cedrus libani were evaluated. The in vitro total phenolic content, the antioxidant, and the antimicrobial activities were determined using the Folin-Ciocalteu reaction, the DPPH radical scavenging assay and the disc diffusion method, respectively. The results of the present study showed that the extracts of the female cones prepared in methanol had the antimicrobial activity against the test microorganisms and the highest antimicrobial effect was observed against Staphylococcus epidermidis, Staphylococcus aureus, and Bacillus subtilis. The total phenolic constituents of the extracts were determined to be in the ranges from 69 to 220 mg GA/100 g. All extracts exhibited antioxidant activity with concentrations necessary to inhibit the activity of DPPH radical by 50% (IC50) ranging from 0.35 to 17.21 µg/mL. The results indicate that the extracts of the cones exhibit acceptable antioxidant and antimicrobial activities and suggest that these cones’ extracts may serve as a potential source of natural antioxidants and antimicrobials for food or medical purposes.