Isolation, Molecular Characterization, and Antimicrobial Profiling of Fructans from Cichorium intybus

Abstract

Fructans are fructose-based oligomers that function as reserve carbohydrates in several plant species, with notable abundance in the Asteraceae family. In Cichorium intybus (chicory), fructan biosynthesis is regulated by two key enzymes, sucrose: sucrose 1-fructosyltransferase (1-SST) and fructan: fructan 1-fructosyltransferase (1-FFT). The present study aimed to isolate, purify, and characterize fructans from chicory, alongside assessing their antimicrobial potential and associated genetic markers. Organic extracts were prepared using NaOH, HCl, ethanol, and chloroform, and their antimicrobial activity was evaluated against Escherichia coli, Bacillus cereus, and Streptococcus pneumoniae. Chloroform and NaOH extracts exhibited the strongest antibacterial effects. Genomic DNA was isolated using the CTAB method, followed by PCR amplification with 1-SST and 1-FFT primers. Sequencing and phylogenetic analysis confirmed high similarity (>97%) of chicory gene sequences with related species, while revealing distinct SST and FFT sequences unique to C. intybus. Phylogenetic clustering linked chicory genes with members of Taraxacum, Lactuca, and Cynara, all known for fructan biosynthesis. These findings highlight chicory as a rich source of fructans with potential applications in functional foods, nutraceuticals, and biotechnological processes, while also providing molecular insights into its unique fructan biosynthetic genes.