abstract
Cuticular fractions of the important northern berries sea buckthorn (Hippophae rhamnoides) and black currant (Ribes nigrum), and the suberized membrane of red peel potato (Solanum tuberosum var. Asterix), were investigated for the first time with solid state spectroscopic methods. In addition, the ester-bonded aliphatic monomers were analyzed as TMS derivatives by GC-MS after depolymerization with NaOMe catalyzed methanolysis. The fractions inspected by solid state C-13 CP-MAS NMR and FT-IR spectroscopy included isolated cuticular and suberin-enriched membranes, i.e. raw cutin and suberin, the non-depolymerizable fractions and further cellulase- and pectinase-resistant fractions. Spectroscopic results supported the findings of the monomeric composition of ester-bound cutin, confirmed the presence of polysaccharides and an aromatic, possibly lignin-like, fraction and also suggested the presence of a nondegradable cutan-type polymer in the berry cuticular fraction. Black currant peel cutin and receptacle cutin were found to differ from each other in composition, notably in terms of the abundance of monomeric, aromatic and polysaccharide fractions. Some effect of latitudinal growth on the composition of cuticular fractions was observed for black currants grown in northern and southern Finland. The spectra of potato suberin were similar to the spectra of black currant receptacles, but the berry had even higher proportio'ns of aromatic components. (C) 2010 Elsevier Inc. All rights reserved.
keywords
NUCLEAR-MAGNETIC-RESONANCE; CHAIN HYDROXY ACIDS; PLANT CUTINS; BLACK-CURRANT; DIETARY FIBER; CUTICLE; POLYMERS; APPLE; CORK
subject category
Chemistry; Food Science & Technology
authors
Jarvinen, R; Silvestre, AJD; Gil, AM; Kallio, H
our authors
Ana Maria Pissarra Coelho Gil
Associate Professor with Aggregation
Armando Jorge Domingues Silvestre
Full professorGroups
G4 - Renewable Materials and Circular Economy
G5 - Biomimetic, Biological and Living Materials
acknowledgements
This research was financially supported by the ABS Graduate School and the Finnish Funding Agency for Technology and Innovation (TEKES) for the project LIPFUN, COST Action 928, Turku University Foundation and Association of Finnish Chemical Societies. The authors would like to thank Gisela Cunha, Mika Kaimainen, Isabel Martins and Henna Rauhala for technical assistance. MTT Agrifood Research Finland is thanked for the berries and Perunajaloste Koivuranta for the potatoes.