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Abstract: Hymenaea stigonocarpa, is an endemic tree from the Brazilian cerrado (savannah) and popularly known as jatobá-do-cerrado. The wood of this species is resistant to biodegradation and is used in naval and civil construction. Cuttings from heartwood of this species showed resistance to fungi and termites. In this paper, we report the antitermitic and antioxidant activities of H. stigonocarpa heartwood ethyl acetate extract and its main flavonoids constituents, hultenin (1), taxifolin (2), quercetin (3) and 7-methoxycathequin (4). The structure elucidation of the isolated flavonoids was performed by spectroscopic methods. The ethyl acetate extract possesses highest antitermitic and antioxidant activity when compared with isolated flavonoids. [Copyright &y& Elsevier]

Abstract: This research evaluated the natural resistance of five woods to the white-rot wood-destroying fungus Phanerochaete chrysosporium under laboratory conditions and in nature. The studied species were Hymenaea stigonocarpa, Anadenanthera colubrina, Caesalpinia ferrea, Manilkara huberi and Delonix regia. The natural resistance to decay is one of the most important properties of wood, mainly assigned to lignin and extractives of wood. A. colubrina has the highest content of extractives and M. huberi the highest content of lignin; both are known as resistant to xylophagous organisms and were also most resistant to the tested fungus. C. ferrea has the lowest content of extractives and D. regia of lignin; both species did not inhibit the fungus Phanerochaete chrysosporium. H. stigonocarpa occupies an intermediate position in content of extractives and lignin as well in resistance to P. chrysosporium. [ABSTRACT FROM AUTHOR]

Abstract: Antitermitic activity of extractives from three Brazilian hardwoods timber known for their high resistance to biodegradation, Bowdichia virgilioides, Anadenanthera colubrina, and Hymenaea stigonocarpa, were evaluated in laboratory tests against termites Nasutitermes corniger. The data obtained in this study suggest that all extracts tested contained antitermitic compounds against this termite species. Alkaloidal extract from B. virgilioides heartwood exhibited the highest antitermitic activity (LC50 = 7.2 mg ml−1 after 4 days) followed by cyclohexane extracts from the same species (LC50 = 12.2 mg ml−1 after 4 days) and H. stigonocarpa heartwood (LC50 = 11.9 mg ml−1 after 4 days) and ethyl acetate extract from Anadenanthera colubrina wood (LC50 = 17.3 mg ml−1 after 4 days). Exposure of N. corniger to the other extracts from A. colubrina wood and H. stigonocarpa heartwood resulted in a higher termite survival rate than for the above mentioned extracts, but still reduced the survival of termites compared to a corresponding control. Only B. virgilioides cyclohexane extract presented repellent properties. The termite resistance of these hardwoods can be attributed to antitermitic activity of secondary metabolites present in the extracts. [Copyright &y& Elsevier]