Tailored chitosan integration in diatomaceous earth particles as a scaffold for fructosyltransferase immobilization in fructo‐oligosaccharide production

Abstract

BackgroundFructo‐oligosaccharide (FOS) belongs to the group of short inulin‐type fructans and is one of the most important non‐digestible bifido‐oligosaccharides capable of biotransforming sucrose using fructosyltransferases (FTase). However, there are no immobilized FTase products that can be successfully used industrially. In this study, diatomite was subjected to extrusion, sintering, and granulation to form diatomaceous earth particles that were further modified via chitosan aminomethylation for modification. FTase derived from Aspergillus oryzae was successfully immobilized on the modified support via covalent binding.ResultsThe immobilized enzyme activity was 503 IU g−1 at an enzyme concentration of 0.6 mg mL−1, immobilization pH of 7.0, and contact time of 3 h. Additionally, the immobilization yield was 56.91%. Notably, the immobilized enzyme is more stable under acidic conditions. Moreover, half‐life of the immobilized enzyme was 20.80 and 10.96‐times as long as the free enzyme at 45 and 60 °C, respectively. This study shows good reusability, as evidenced by the 84.77% retention of original enzyme activity after eight cycles. Additionally, the column transit time of the substrate was approximately 35.56 min when the immobilized enzyme was applied in a packed‐bed reactor. Furthermore, a consistently high FOS production yield of approximately 60.68% was achieved and maintained over the 15‐d monitoring period.ConclusionsOur results suggest that immobilized FTase as a viable candidate for continuous FOS production on an industrial scale.This article is protected by copyright. All rights reserved.