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In situ investigation and visualisation of microbial attachment and colonisation in a heap bioleach environment / Cindy-Jade Africa in Minerals engineering, Vol. 23 N° 6 (Mai 2010) 

Public ISBD [article]  in Minerals engineering > Vol. 23 N° 6 (Mai 2010) . - pp. 486–491 Titre : In situ investigation and visualisation of microbial attachment and colonisation in a heap bioleach environment : The novel biofilm reactor Type de document : texte imprimé Auteurs : Cindy-Jade Africa, Auteur ; Susan T.L. Harrison, Auteur ; Megan Becker, Auteur Année de publication : 2011 Article en page(s) : pp. 486–491 Note générale : Génie Minier Langues : Anglais (eng) Mots-clés : Bioleaching  Microbial  attachment  Biofilm  A.  ferrooxidans  L.  ferriphilum  Fluorescent  in  situ  hybridisation Résumé : In this paper, the development of a novel means of investigating the attachment and subsequent biofilm formation of mineral bioleaching micro-organisms to mineral surfaces in situ is described. The protocol was developed to investigate the interactions of micro-organisms with sulfide minerals and low-grade chalcopyrite ore under conditions resemblant of a bioheap environment. The method makes use of a biofilm reactor in which thin sections of mineral ore are mounted. The reactor is operated as a continuous flow-through system. Attachment of pure and mixed cultures of Acidithiobacillus ferrooxidans and Leptospirillum ferriphilum is assessed. The technique allows for the investigation of microbial ecology with special regard to microbe–mineral attachment, site and mineral specific associations of micro-organisms and spatial organisation of microbial communities present through the use of fluorescent microscopy techniques. Preliminary fluorescent in situ hybridisation (FISH) analysis of the attachment of L. ferriphilum and A. ferrooxidans to massive chalcopyrite sections, as well as to low-grade chalcopyrite containing ore sections is presented. In the case of both low-grade and massive sulfide mineral samples, attachment of mixed micro-colonies was observed in regions where surface defects were prevalent. In low-grade samples, preferential attachment was observed in regions where sulfide minerals were present. The density of the attached micro-colonies increased with an increase in contacting time (from 20, 72 and 96 h) and was indicative of an actively growing mono-layered biofilm. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509003203 [article] In situ investigation and visualisation of microbial attachment and colonisation in a heap bioleach environment : The novel biofilm reactor [texte imprimé] / Cindy-Jade Africa, Auteur ; Susan T.L. Harrison, Auteur ; Megan Becker, Auteur . - 2011 . - pp. 486–491. Génie Minier Langues : Anglais (eng) in Minerals engineering > Vol. 23 N° 6 (Mai 2010) . - pp. 486–491 Mots-clés : Bioleaching  Microbial  attachment  Biofilm  A.  ferrooxidans  L.  ferriphilum  Fluorescent  in  situ  hybridisation Résumé : In this paper, the development of a novel means of investigating the attachment and subsequent biofilm formation of mineral bioleaching micro-organisms to mineral surfaces in situ is described. The protocol was developed to investigate the interactions of micro-organisms with sulfide minerals and low-grade chalcopyrite ore under conditions resemblant of a bioheap environment. The method makes use of a biofilm reactor in which thin sections of mineral ore are mounted. The reactor is operated as a continuous flow-through system. Attachment of pure and mixed cultures of Acidithiobacillus ferrooxidans and Leptospirillum ferriphilum is assessed. The technique allows for the investigation of microbial ecology with special regard to microbe–mineral attachment, site and mineral specific associations of micro-organisms and spatial organisation of microbial communities present through the use of fluorescent microscopy techniques. Preliminary fluorescent in situ hybridisation (FISH) analysis of the attachment of L. ferriphilum and A. ferrooxidans to massive chalcopyrite sections, as well as to low-grade chalcopyrite containing ore sections is presented. In the case of both low-grade and massive sulfide mineral samples, attachment of mixed micro-colonies was observed in regions where surface defects were prevalent. In low-grade samples, preferential attachment was observed in regions where sulfide minerals were present. The density of the attached micro-colonies increased with an increase in contacting time (from 20, 72 and 96 h) and was indicative of an actively growing mono-layered biofilm. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509003203