Antioxidant and antifungal potential of methanol extracts of Phellinus spp. from Sonora, Mexico

Background: Among the potential natural sources of bioactive compounds, those of the macroscopic fungi Phellinus spp. have been identified by previous researches. Phenolic compounds are among the major antioxidant and antimicrobial contributors due to their bioactive properties. Aims: The goal of this study was to determine the total phenolic and flavonoid contents, and its relation with the antioxidant and antifungal activity of methanolic extracts of Phellinus gilvus, Phellinus rimosus and Phellinus badius, respectively. Methods: The collected and identified organisms of Phellinus spp. were treated with methanol and the generated aqueous extract was analyzed to quantified total phenolic compounds, total flavonoids, radical scavenging activity against DPPH. trolox equivalent antioxidant capacity, and oxygen absorbance capacity. The antifungal property of the extracts was evaluated against Alternaria alternata. Results: The content of phenolic compounds was of 49.31, 46.51 and 44.7 mg of gallic acid equivalents/g, for P. gilvus, P. rimosus and P. badius, respectively. The total flavonoid content followed the same pattern with values of 30.58, 28, and 26.48 mg of quercetin equivalents/g for P. gilvus, P. rimosus and P. badius, respectively. The variation on the content of phenolic components was reflected on the antioxidant activity of every organism. The antioxidant activity ranked as follows: P. gilvus > P. rimosus > P. badius. The antifungal effect of the different extracts against A. alternata showed a significant effect, all of them, inhibiting the growth of this pathogen. Conclusions: P. gilvus showed the best potential to inactivate free radicals, being all the tested fungi effective to inhibit A. alternata growth. (C) 2011 Revista Iberoamericana de Micologia. Published by Elsevier Espana, S.L. All rights reserved.