Radical scavenging activity of an inulin-gallic acid graft and its prebiotic effect on Lactobacillus acidophilus in vitro growth

• Published in: Journal of functional foods Vol. 29; pp. 135 - 142
• Main Authors: Arizmendi-Cotero, Daniel, Villanueva-Carvajal, Adriana, Gómez-Espinoza, Rosa María, Dublán-García, Octavio, Dominguez-Lopez, Aurelio
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-02-2017; Elsevier
• Subjects: Inulin; Molecular grafting; Prebiotics; Radical scavenging activity; Molecular grafting; Radical scavenging activity; Inulin; Prebiotics
• ISSN: 1756-4646; 2214-9414
• DOI: 10.1016/j.jff.2016.12.014

•To get an antioxidant-prebiotic dietary fibre, gallic acid was grafted onto inulin.•UV spectra show peaks at 214 and 266–268nm proving an aromatic ring in the graft.•FT-IR spectra show a band at 1743cm−1, settling a covalent bond among inulin and GA.•Gallic acid (GA) provides a significant antioxidant capacity to Inulin-GA graft.•Gallic acid grafted onto inulin does not interfere with its prebiotic capacity.
In order to generate a new antioxidant and prebiotic dietary fibre, gallic acid (GA) was grafted onto native inulin. Inulin-gallic acid (IGA) graft was confirmed by UV and infrared spectroscopy (FT-IR). The antioxidant activity was evaluated by spectroscopic methods and the prebiotic activity of IGA was determined by In-Vitro growth of Lactobacillus acidophilus. UV spectra show absorbance peaks at 214 and 266–268nm showing aromatic ring presence in the IGA graft and FT-IR spectra showed a band at 1743cm−1, confirming the covalent bond between the polymer and GA. GA provides a significant antioxidant capacity to IGA graft. Inulin shows a significant capacity to stimulate the growth of L. acidophilus and GA grafted onto inulin (16.3mg/g polymer) does not interfere with its prebiotic capacity. It is possible to provide radical-scavenging capacity to inulin-type fructo-oligosaccharides avoiding the decrease of its prebiotic properties, which could extend their potential use as functional foods.