Chitosan nanoencapsulation of flavonoids enhances their quorum sensing and biofilm formation inhibitory activities against an E.coli Top 10 biosensor.
Colloids Surf B Biointerfaces
; 164: 125-133, 2018 Apr 01.
Article
em En
| MEDLINE
| ID: mdl-29413589
ABSTRACT
Phytochemicals have been found to be promising alternatives to conventional antibiotic therapies for the control of bacterial infections, as they may entail less selective pressure and hence reduce the development of resistance. This study involved examining the inhibition of biofilm formation and of quorum sensing (QS), and the cytotoxicity on mammalian cells of two flavonoids, quercetin and baicalein, in free form and associated into chitosan-based nanocapsules. This was done by use of a transformed E. coli Top 10 biosensor strain, while the cytotoxicity was evaluated on MDCK-C7 cells. In free form, application both flavonoids exhibited slight inhibitory activity on the QS response and biofilm formation, a scenario that was improved positively upon encapsulation with chitosan (Mw â¼115,000â¯g/mol and DA â¼42%). The association efficiency of 99% (quercetin) and 87% (baicalein) was determined, and each formulation had an average diameter of 190⯱â¯4 and 187⯱â¯2â¯nm, and zeta (ζ) potential of +48.1⯱â¯2.03 and +48.4⯱â¯3.46â¯mV, respectively. Both types of systems were stable against aggregation in M9 and MEM media. The in vitro release kinetics data of both flavonoids seemed to be similar with only â¼20% released over the first 5â¯h, or â¼10% over the first 4â¯h, respectively, with subsequent sudden release increase up to â¼40% in both cases. The free phytochemicals seemed to be cytotoxic to MDCK-C7 cells at higher doses, however, upon nanoencapsulation, a cytoprotective effect was evidenced. We have gained proof-of-principle of the advantages of encapsulation of two bioactive flavonoids.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Flavonoides
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Técnicas Biossensoriais
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Biofilmes
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Quitosana
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Escherichia coli
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Nanocápsulas
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Percepção de Quorum
Limite:
Animals
Idioma:
En
Revista:
Colloids Surf B Biointerfaces
Assunto da revista:
QUIMICA
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Alemanha