| Gaia: | Condensed tannins and total phenols content expressed as tannic acid were evaluated on ethanolic and aqueous extracts from bark of eight Pinus species abundant at Durango State forests. Ethanolic extracts were obtained by soaking bark 48 h with 50 % aqueous ethanol and the aqueous extracts with hot water. Condensed tannins were evaluated by the Stiasny number and total phenols by the Folín-Ciocalteu method. Extract yields, Stiasny number, condensed tannins and total phenols were higher in ethanolic extracts, for all species. Statistical differences were found between extraction solvents and species. Ethanolic extracts of P. leiophylla, P. ayacahuite, P. durangensis and P. teocote barks showed the highest concentration of condensed tannins and phenols, while P. cooperi and P. engelmannii showed the lowest.
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