Autor(es):
Franco, A. R. 
; Calheiros, C. S. C. ; Pacheco, C. C. ; Marco, P. De ; Manaia, C. M.
Data: 2005
Identificador Persistente: http://hdl.handle.net/10400.14/6729
Origem: Veritati - Repositório Institucional da Universidade Católica Portuguesa
Descrição
The culturable bacteria colonizing the rhizosphere of plants growing in the area of discharge of a tannery effluent were characterized. Relative proportions of
aerobic, denitrifying, and sulfate-reducing bacteria were determined in the rhizosphere of Typha latifolia, Canna indica, and Phragmites australis. Aerobic bacteria were
observed to be the most abundant group in the rhizosphere, and plant type did not seem to influence the abundance of the bacterial types analyzed. To isolate bacteria able to degrade polyphenols used in the tannery
industry, enrichments were conducted under different conditions. Bacterial cultures were enriched with individual polyphenols (tannins Tara, Quebracho, or Mimosa) or with an undefined mixture of tannins present in
the tannery effluent as carbon source. Cultures enriched with the effluent or Tara tannin were able to degrade tannic acid. Six bacterial isolates purified from these
mixed cultures were able to use tannic acid as a sole carbon source in axenic culture. On the basis of 16S ribosomal DNA sequence analysis, these isolates were closely related to organisms belonging to the taxa
Serratia, Stenotrophomonas maltophilia, Klebsiella oxytoca, Herbaspirillum chlorophenolicum, and Pseudomonas
putida.
