Phytochemical screening and antivirulence properties of Ceiba pentandra and Ceiba aesculifolia (Malvaceae) bark extracts and fractions.

Abstract

Background: Inhibition of quorum sensing systems (QSS-I) is a novel strategy in the treatment of bacterial infections. To date, plants are the major source of metabolites with this inhibitory activity. Thus, species of Mexican flora can be important resources for obtaining metabolites with QSS-I activity. Hypothesis: We hypothesized that extracts from species of the genus Ceiba have metabolites with inhibitory activity against bacterial quorum sensing systems. Species studied: Ceiba pentandra (L.) Gaertn. and Ceiba aesculifolia (Kunth) Britten &Baker f. (Malvaceae). Study site and years of study: We collected Ceiba bark in the municipalities of Tierra Blanca, Veracruz, and Acatlan, Oaxaca, in August 2013. Methods: We determined the effect of extracts from C. aesculifolia and C. pentandra against QSS-regulated phenotypes of Chromobacterium violaceum and Pseudomonas aeruginosa. Extracts were fractionated and the main metabolites were identified. As support in the identification of the species, we carried out an anatomical study of the bark. Results: Hexane and dichloromethane extracts of both species of Ceiba exhibited QSS-I activity. We identified four fractions rich in terpene and sterol compounds with the ability to attenuate virulence factors in P. aerugiosa. The histological analysis appears to support the presence of some differences in the barks that can facilitate identification of the two species. Conclusions: The extracts and fractions of the two species of Ceiba are sources of phytochemicals with the ability to regulate bacterial quorum sensing systems positively or negatively.