Isolation of prebiotics from wild vegetables: In vitro characterization by antioxidant assays and human adenocarcinoma cell line (HT-29)

Abstract

Wild vegetables are recognized for their antioxidants, fibres, other bioactive components and consumed as a rich prebiotic source along with probiotics. Crude prebiotics were isolated from wild vegetables and extracts were treated with digestive enzymes to enrich non-digestible prebiotics. The prebiotics were used to prepare different synbiotic formulations with Lactobacillus plantarum strains, L. bulgaricus and L. lactis whereas inulin served as a positive control. These formulations were evaluated for antioxidant activities viz. lipopolysaccharide-induced cell survival assessment and microbial cell adhesion using the HT-29 cell line. All formulations showed significant antioxidant activity. L. plantarum, L. plantarum (LB-VII) and L. bulgaricus with prebiotic Emblica officinalis showed highest DPPH radical scavenging activity (≈85%). ABTS radical scavenging activity was maximum for L. plantarum (LB-VII) with E. officinalis (57%). L. bulgaricus with E. officinalis showed highest FRAP activity (≈515 μM). Cell survival was restored in presence of prebiotics and maximum was observed in L. plantarum (LB-VII) with E. officinalis (77.8%) and the highest microbial cell adhesion was 76% of L. bulgaricus with E. officinalis. Microscopic cell adhesion assay showed successful adhesion to mucus secreted by HT-29 cells. This study underlines and provides evidence for the usage of wild vegetables as a source of prebiotics.