Fungal endoinulinase production from raw Asparagus inulin for the production of fructooligosaccharides

Abstract

In present study, statistical optimization of medium composition for endoinulinase production from raw inulin using Aspergillus tritici was performed in shake-flask fermentations. The concentration of four independent variables viz. raw inulin (1.5–3.5%), peptone (0.2–1.8%), (NH4)H2PO4 (0.2–1.8%) and pH (4.5–6.5) was explored to optimize the composition of fermentation medium for maximum endoinulinase production. Fermentation medium containing 2.5% raw inulin, 1% peptone, 1% (NH4)H2PO4 and medium pH adjusted to 5.5 supported maximum (25.39 IU/mL) endoinulinase production. Adequate precision value >4, closeness of coefficient of determination (R2) value to 1, good co-relation between the predicted and experimental values, percentage error <5%, high F-value 164.52 and low Lack of fit F-value 0.19 authenticates the fitness of quadratic model. TLC fingerprints studies confirmed fructooligosaccharides synthesis from inulin by crude fungal endoinulinase. Fructooligosaccharides yield (19.40%) containing 3.70% ketose (GF2), 2.71% nystose (GF3) and 1.42% fructofuranosyl nystose (GF4) were obtained from inulin (10%).