Antioxidant polysaccharide-enriched fractions obtained from olive leaves by ultrasound-assisted extraction with α-amylase inhibition, and antiproliferative activities

• Published in: 3 Biotech Vol. 14; no. 3; p. 92
• Main Authors: Elayeb, Rania, Bermúdez-Oria, Alejandra, Lazreg Aref, Houda, Majdoub, Hatem, Ritzoulis, Christos, Mannu, Alberto, Le Cerf, Didier, Carraro, Massimo, Achour, Sami, Fernández-Bolaños, Juan, Trigui, Maher
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.03.2024; Springer Nature B.V; Springer
• Subjects: Agriculture; Amylases; Antioxidants; Antiproliferatives; Arabinose; Bioinformatics; Biological effects; Biomaterials; Biotechnology; Cancer Research; Chemical Sciences; Chemistry; Chemistry and Materials Science; Colorimetry; Fractions; Free radicals; Functional foods & nutraceuticals; Galactose; Macromolecules; NMR; Nuclear magnetic resonance; Original Article; Polyphenols; Polysaccharides; Proteins; Scavenging; Stem Cells; Synergistic effect; Tumor cell lines; Ultrasonic imaging; Ultrasonic testing; Ultrasound; Uronic acid; α-Amylase; Polysaccharides–polyphenol–protein complex; Non-conventional method; Caco-2 cell line; In vitro activities; Olive by-products; Olea europaea l.,. Olive by-products
• ISSN: 2190-572X; 2190-5738
• DOI: 10.1007/s13205-024-03939-2

Polysaccharide-rich materials were extracted from the alcohol-insoluble solids of Olea europaea l. **leaves. Structural characteristics were determined by colorimetric techniques, FT-IR, GC–MS, SEC/MALS/VD/DRI, and NMR ( 1 H, 13 C). The extract and its main macromolecular components were characterized to assess their ability toward antioxidant, α-amylase inhibition, and antiproliferative activities. Results revealed that the ultrasound olive leave extract comprises polysaccharides with uronic acid, galactose, arabinose, and glucose in molar percentages of 11.7%, 11.3%, 7.5%, and 4.9% respectively, constituting 41% of the total mass. In addition, polyphenols (21%) and proteins (9%) are associated with these polysaccharides. Further, the extract showed noticeable ORAC and free radical scavenging abilities, in addition to high in vitro antiproliferative activity against Caco-2 colon carcinoma cell lines. Similarly, the extract exhibited a strong, uncompetitive inhibition of α-amylase by 75% in the presence of the extract with 0.75 µg/mL of concentration. This research concludes that ultrasound extraction method can be used for the extraction of polysaccharide–polyphenol–protein complexes. These conjugates exhibit the potential for combined biological activities resulting from a synergistic effect of its compounds, making them promising ingredients for the development of functional food.