Isolation of bioactive polysaccharide from acorn and evaluation of its functional properties

The aim of this study was to evaluate the prebiotic potential and some functional properties of polysaccharides isolated from acorn fruit. The FTIR spectrum of isolated acorn polysaccharide (IAP) showed the typical bands corresponding to sugars and polysaccharides. The IAP was resistant to simulated acidic and enzymatic digestion even more than Inulin (In). The prebiotic activity, which was tested using IAP as a carbon source, showed significant increase in the growth and viability of Lactobacillus plantarum A7 (probiotic). Viability of Lactobacillus plantarum A7 in IAP and In supplemented media was stable even after 72 h, whereas in glucose supplemented medium, bacterial growth showed a notable decrease after 24 h. Lipid absorption capacity (LAC) and water holding capacity (WHC) of IAP were 5.44 ± 0.02 (g oil/g DM) and 4.33 ± 0.03 (g water/g DM), respectively, which were comparable to some dietary fibers and were more than In. IAP scavenged DPPH radicals by 82.24%. IAP was found to have a high scavenging ability compared to the reference prebiotic (In), giving a scavenging ability of about 20%. Therefore, due to prebiotic capability, high WHC, LAC and good antioxidant activity, IAP can be a suitable candidate for technological applications and health improving effects in functional food.