abstract
Polysaccharides from pomegranate peel (Wonderful and Purple Queen (R) varieties) were extracted by hot water and fractionated using ethanol. Three fractions (F1-F2-F3) were obtained for each sample. Polysaccharides' yield was higher for Purple Queen (R): 13% dw. Polysaccharides of the three fractions were characterized by size exclusion chromatography (SEC), dynamic light scattering (DLS), 1H NMR, methylation, and acylation degree. Differently from SEC, DLS highlighted some differences between the polysaccharides's molecular sizes of the fractions. The highest methylation and acylation degree was observed for F3 of Purple Queen (R): 74.0% and 18.6%, respectively. The percentage of galacturonic acid confirmed the presence of pectin in almost all the fractions recognized as homogalacturonan. Arabinan and arabinogalactan were also found in all the collected F3 samples, although in different proportions. The stepwise fractionation process followed by a multi -methodological analytical investigation was helpful to improve the knowledge of the pectic polysaccharides of pomegranate.
keywords
PUNICA-GRANATUM; BY-PRODUCTS; EXTRACTION; INSIGHT
subject category
Chemistry; Food Science & Technology; Nutrition & Dietetics
authors
Balli, D; Khatib, M; Cecchi, L; Adessi, A; Nunes, C; Melgarejo, P; Coimbra, MA; Mulinacci, N
our authors
Cláudia Nunes
Junior Researcheracknowledgements
This study was partially funded by University of Florence. This work was financed by national funds through the Portuguese Foundation for Science and Technology/MCTES within the scope of project CICECO Aveiro Institute of Materials (UIDB/50011/2020 & UIDP/50011/2020) and LAQV-REQUIMTE (UIDB/50006/2020), as well as in framework contract foreseen in the numbers 4, 5 and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19.