Production of Purified Free and Immobilized Exo-Inulinase from Aspergillus terreus AUMC 11628 by Solid State Fermentation for Degradation of Dahlia Tubers and Chicory Roots Inulin Mixture and Ethanol Production

Housseiny, Manal; Habib, Mohammad

doi:10.21608/ejchem.2022.133385.5919

Production of Purified Free and Immobilized Exo-Inulinase from Aspergillus terreus AUMC 11628 by Solid State Fermentation for Degradation of Dahlia Tubers and Chicory Roots Inulin Mixture and Ethanol Production

Document Type : Original Article

Authors

Manal Housseiny ¹
mohammad habib ²

¹ Biological and Geological Sciences Department Faculty of Education, Ain Shams University

² 1-Chemistry Department, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSIU), P.O. 90950 (11623), Riyadh, KSA 2-National Research Center El-Bohoth-Dokki. Eltahrir ST. Dokki, Cairo

10.21608/ejchem.2022.133385.5919

Abstract

The mixture of both Dahlia (Dahlia pinnata) tubers and Chicory (Cichorium intubus) roots has the potential to be an effective and cost-efficient substrate for Exo-inulinase production more than each alone. Five Aspergillus species were also examined for maximum production of Exo-inulinase activities when grown on aforementioned mixture. Aspergillus terreus was the potent on a ratio of (5:1 w/w Dalia: Chicory, respectively) producing the maximum levels of inulinase at 45 ºC, pH 7.0, seven days of incubation, 50 % moisture and peptone as the best nitrogen source. With 70.23 purification fold, inulinase was purified to homogeneity. Studying of inulinase thermal stability for 2 hours at 60 °C revealed a significant reduction in the free enzyme activity when compared to the immobilized one. With a 75.65 % immobilization yield, inulinase was successfully immobilized. The sodium alginate beads passed the reusability test after 10 cycles and 20 days of storage at 4°C. These findings imply that inulinase in its immobilized form could be a potential candidate for pure fructose syrups production. It was also found that ethanol production by both free and immobilized inulinase was achieved using two processes; direct conversion and Sequential hydrolysis and fermentation of inulin into ethanol using Saccharomyces cerevisiae for fermentation sugars into ethanol. To the best of our knowledge, there is the first report about immobilized inulinase production by Aspergillus terreus using Dalia tubers and Chicory roots mixture and its usage in ethanol production.

Keywords