Portraying manganese biofilms via a merger of EPR spectroscopy and cathodic polarization.
Biofouling
; 35(7): 768-784, 2019 08.
Article
em En
| MEDLINE
| ID: mdl-31530181
ABSTRACT
Microbial biofilms on stainless steel surfaces exposed to water from a freshwater pond were dominated by manganese-oxidizing bacteria, as initially diagnosed by microscopy and elemental analysis. The application of electron paramagnetic resonance (EPR) spectroscopy revealed conspicuous sextet (six-line) patterns that intensified with immersion time, implying the gradual accumulation of Mn(II) in the biofilms. Correspondingly, cathodic polarization designated the manganese oxide (MnOx) reduction peak in the form of a distinctive 'nose', which grew increasingly more negative with biofilm growth. The progressive expansion of cathodic current densities and the concurrent area-under-the-curve also allowed the quantification of microbially mediated MnOx deposition. Furthermore, the merger of EPR and cathodic polarization techniques yielded key insights, in tandem with Mn speciation data, into the pathways of microbial manganese transformations in biofilms, besides providing meaningful interpretations of prevailing literature. Accordingly, the natural freshwater biofilm was inferred as one supporting a complete manganese cycle encompassing multiple redox states.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Biofilmes
/
Manganês
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Biofouling
Assunto da revista:
BIOLOGIA
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Índia