The use of whole-cell biocatalyst for production of fructo-oligosaccharide (FOS) eliminates the need for costly enzyme recovery and purification. In this study, a novel Aureobasidium pullulans strain (FRR 5284) was identified from seven A. pulllulans strains as an efficient whole-cell biocatalyst for FOS production. The strain had a specific intracellular transfructosylating activity of 4.44 ± 0.18 U/mg dry cells, one of the highest transfructosylating activities thus far reported for whole-cell biocatalyst. Under optimal conditions (pH 5.5 and 55 °C), only 5 g/L of dry cells and 3 h reaction time were required to achieve a FOS yield of 61 % from 50 % (w/v) sucrose. Incubation of sugarcane molasses with an invertase-free Saccharomyces cerevisiae prior to addition of A. pullulans whole-cell biocatalyst eliminated glucose inhibition and increased FOS yield from 44 % to 56 % in 1 h. This study has demonstrated that the novel A. pullulans FRR 5284 was an efficient source of whole-cell biocatalyst for FOS production and a promising strategy for transformation of sucrose and sugarcane molasses into a higher-value prebiotic.
Publication DOI: 10.1016/j.bej.2020.107747Journal NLM ID: 9891831Publisher: Amsterdam; New York, NY: Elsevier
Correspondence: jan.zhang
qut.edu.au
Institutions: Centre for Agriculture and the Bioeconomy, Institute for Future Environments, Queensland University of Technology, Brisbane, Australia, School of Mechanical, Medical, and Process Engineering, Science and Engineering Faculty, Queensland University of Technology, Brisbane, Australia, School of Biology and Environmental Science, Science and Engineering Faculty, Queensland University of Technology, Brisbane, Australia
Methods: HPLC, enzymatic digestion, cell growth, kinetics assay, centrifugation
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