Production of Short Chain Fructo-oligosaccharides from Inulin of Chicory Root Using Fungal Endoinulinase

Short chain fructo-oligosaccharides (SC-FOS) are the potential prebiotics possessing diverse applications in both food and feed industries. The present study was aimed to extract inulin from chicory roots followed by its conversion into SC-FOS applying endoinulinase from Aspergillus fumigatus. The inulin was extracted from chicory roots through boiling in hot water, followed by precipitation with ethanol at room temperature or freezing condition. Maximum yield (42%) of inulin was obtained with three volumes of chilled absolute ethanol at room temperature. HPLC analysis of enzymatic hydrolysate detected kestose (GF2), nystose (GF3), and other FOS having higher degree of polymerization (DP). Maximum GF2 (5.79 mg/ml) was detected at temperature 50 °C, pH 5.5 with 2 U of enzyme dose after 6 h of hydrolysis; while maximum GF3 (4.33 mg/ml) was recorded at 60 °C, 5.5 pH with 0.5 U enzyme dose after 2 h of hydrolysis. Nevertheless, complete hydrolysis of inulin was noticed with 99% total oligosaccharide yield at 55 °C, 5.5 pH with 0.5 U enzyme dose after 4 h of hydrolysis with negligible amount of mono- and di-saccharides. The present finding demonstrated the process for higher yield of inulin from chicory roots followed by its conversion into SC-FOS applying fungal endoinulinase.