Biological activity of extracts from Catalpa bignonioides Walt. (Bignoniaceae)

Catalpa bignonioides Walt. (Bignoniaceae) is a species that belongs to a tropical family but has been introduced in many countries as ornamental. Although this plant is consumed by indigenous cultures of South America for medical uses, experimental studies of the biological properties of Catalpa bignonioides are lacking. The aim of this work was to study the biological activity of crude extracts from either pods, seeds or leaves of Catalpa bignonioides which were collected in Spain. Ethyl ether, butanolic and aqueous fractions of the pod extract were also prepared and studied. We have examined the antimicrobial activity against five bacteria and one yeast, the cytotoxic activity against HepG2 cells and the anti-inflammatory and antinociceptive effects in rodents. A preliminary phytochemical analysis of the extracts and fractions was also conducted. Results showed no antimicrobial or antitumoral effects, but prominent anti-inflammatory and antinociceptive actions of the extracts. These last activities may be a result of the presence of either of saponins, sterols or phenols, mainly found in the leaves and pods of the plants.