Characterization of Fungal Endophytes Isolated from the Metal Hyperaccumulator Plant Vachellia farnesiana Growing in Mine Tailings

Microorganisms

Patricia Mussali-Galante¹  Rosariodel Carmen Flores-Vallejo¹  Efraín Tovar-Sánchez¹  MaríaFernanda Gaitán-Rodríguez²  Julio Mena-Portales³  Giovanni Salazar-Ramírez⁴  JulioCésar Rivera-Leyva⁴  MaríaLuisa Villarreal⁴  JorgeLuis Folch-Mallol⁴  Maríadel Rayo Sánchez-Carbente⁵  Ayixon Sánchez-Reyes⁶  RamónAlberto Batista-García⁷ 

[1] Universidad Autónoma del Estado de Morelos, Cuernavaca 62210, Morelos, Mexico;Universidad Nacional Autónoma de México, Cuernavaca 62210, Morelos, Mexico;Centro de Investigación en Biodiversidad y Conservación, Universidad Autónoma del Estado de Morelos, Cuernavaca 62210, Morelos, Mexico;Centro de Investigación en Biotecnología;Cátedras CONACyT-Instituto de Biotecnología;Facultad de Farmacia, Universidad Autónoma del Estado de Morelos, Cuernavaca 62210, Morelos, Mexico;Instituto de Ecología y Sistemática, Carretera Varona 11835 e/ Oriente y Lindero, Capdevila, Boyeros, 11900 La Habana 19, Cuba;

关键词: bioremediation;    endophytes;    heavy metals;    vachellia farnesiana;    metal solubilization;    organic acids;    antioxidant secondary metabolites;   

DOI  :  10.3390/microorganisms8020226

来源: DOAJ

【 摘 要 】

Heavy metal pollution has become an environmental and health problem worldwide. With the aim of finding novel strategies for metal bioremediation, endophytic fungi from the heavy metal hyperaccumulator plant Vachellia farnesiana were isolated and characterized. The plants were growing in mine tailings, rich in Zn, Pb, and Cu. Morphological and phylogenetic analyses indicated that the fungal strains belonged to Neocosmospora and Aspergillus genera. The Neocosmospora isolate belongs to the Fusarium solani species complex (FSSC) that groups phytopathogen species. However, in this case the plants from which it was isolated did not show any signs of disease. Both fungal strains were able to remove significant amounts of heavy metals from liquid cultures, either in a mixture of the three metals or each metal in a single culture. In response to lead exposure, the Neocosmospora sp. strain secreted specific novel phenolic compounds other than anthraquinones or naphtoquinones, which have been described in similar situations. The Aspergillus sp. dropped the pH in the medium. High-performance liquid chromatography determinations indicated that this strain secreted mainly glutamic acid in response to lead, a novel mechanism, which has not been reported elsewhere. Malic and succinic acids were also produced in response to lead exposure. Possibly, glutamic and succinic acids (synthesized in the Krebs cycle) can be used to cope with metal toxicity due to the plant providing photosynthates to the fungus. These fungi showed the potential to be used for bioremediation or restoration of metal-polluted environments.

【 授权许可】

Unknown