RT Journal Article
T1 Influence of Oxidation and Dialysis of Phlorotannins on Bioactivity and Composition of Ultrasound-Assisted Extracts from Ascophyllum nodosum
A1 Moreira Martínez, Ramón Felipe
A1 Gisbert Verdú, Mauro
A1 Sineiro Torres, Jorge
K1 Phlorotannins
K1 Oxidation
K1 Molecular size
K1 DPPH radical scavenging activity
K1 FTIR
K1 1H-NMR
K1 Bioactivity
K1 Fragmentation
K1 Size distribution
AB The isolation and chemical characterization of phlorotannins has gained special attention in recent years due to their specific health-promoting benefits. Flow-cell ultrasound-assisted extraction (90 W/cm2 of sonication power, 2 min of retention time and 20 g solvent/g algae of liquid–solid ratio) was carried out by using double-distilled water (WE) and acetone:water mixture (AWE) as extraction solvents. The AWE showed a higher total polyphenols content (TPC), carbohydrates (CHOs) and antioxidant activities than WE. However, when the WE was purified by using Amberlite XAD16 column, the purified WE (PWE) showed similar a TPC, decreased CHOs and increased antioxidant activity compared to WE. The oxidation of the PWE extract was evaluated under natural, forced and severe oxidation condition for 120 h. Only severe oxidation conditions were able to significantly reduce TPC and antioxidant activities. PWE was dialyzed (20, 10, 3.5 and 2 kDa). The main bioactive fraction of phlorotannins was obtained from 10 to 20 kDa. CHOs were distributed in fractions below 20 kDa. MALDI-TOF analysis was performed for PWE, PD20 and PD2 extracts to analyze the degree of polymerization of phlorotannins, which ranged from 4 to 17 phloroglucinol units/molecule. Fragmentation patterns allowed the proximate identification of several phlorotannins in Ascophyllum nodosum extracts
PB MDPI
YR 2022
FD 2022-11-11
LK http://hdl.handle.net/10347/31754
UL http://hdl.handle.net/10347/31754
LA eng
NO Gisbert, M., Sineiro, J., Moreira, R. (2022). Influence of Oxidation and Dialysis of Phlorotannins on Bioactivity and Composition of Ultrasound-Assisted Extracts from Ascophyllum nodosum. "Marine Drugs", vol. 20, 706
NO This work was supported by the Ministry of Science and Innovation of Spain and European Regional Development Fund (ERDF) of European Union by the research project (RTI2018–095919–B–C2R) and Xunta de Galicia, Spain (Consolidation Project ED431B 2019/01).
DS Minerva
RD 28 abr 2026