Chitosan does not inhibit enzymatic action of human pancreatic lipase in Langmuir monolayers of 1,2-didecanoyl-glycerol (DDG)

Date
2014-11-01Author
Souza, Adriano L.
Pavinatto, Felippe J.
Caseli, Luciano [UNIFESP]
Volpati, Diogo
Miranda, Paulo B.
Oliveira, Osvaldo N.
Type
ArtigoISSN
0927-7765Is part of
Colloids and Surfaces B-biointerfacesDOI
10.1016/j.colsurfb.2014.10.040Metadata
Show full item recordAbstract
In this study, we tested the hypothesis according to which chitosan reduces lipid digestion by blocking the access of lipases to ingested fat. Because lipase action takes place mostly at interfaces, we produced Langmuir films of 1,2-didecanoyl-glycerol (DOG), which is the substrate for human pancreatic lipase (HPL). the experimental assays were carried out in acidic medium, at pH 3.0, to ensure that chitosan is completely soluble. Chitosan was found to affect strongly the surface activity of HPL that forms a Gibbs monolayer at the air/water interface, but did not inhibit the enzymatic action of HPL toward the DDG monolayer. the latter was observed using two surface-specific spectroscopic techniques, namely polarization-modulated infrared reflection-absorption and sum-frequency generation (SFG). the extension of DOG hydrolysis calculated using SFG spectroscopy was 33% in the absence of chitosan, and ranged from 29 to 50% in the presence of chitosan at concentrations of 0.20 g L-1 and 0.30g L-1, respectively. Therefore, fat protection by chitosan is unlikely to be an important factor in fat reduction. (C) 2014 Elsevier B.V. All rights reserved.
Citation
Colloids and Surfaces B-biointerfaces. Amsterdam: Elsevier B.V., v. 123, p. 870-877, 2014.Keywords
ChitosanFat reduction
Human pancreatic lipase
Langmuir monolayers
Sum-frequency generation spectroscopy
Sponsorship
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Collections
- Em verificação - Geral [7517]