Santos Moriano, Paloma CarmenKidibule, Peter E.Alleyne, ElenaBallesteros, Antonio O.Heras, ÁngelesFernández Lobato, MaríaPlou, Francisco J.2019-07-102019-07-102018Santos-Moriano, P., Kidibule, P. E., Alleyne, E., Ballesteros, A. O., Heras, A., Fernandez-Lobato, M., & Plou, F. J. (2018). Efficient conversion of chitosan into chitooligosaccharides by a chitosanolytic activity from Bacillus thuringiensis. Process Biochemistry, 73, 102–108. https://doi.org/10.1016/j.procbio.2018.07.0171359-51131873-3298http://hdl.handle.net/11268/8118Starting from a commercial preparation of Bacillus thuringiensis var. aizawai, widely employed as biopesticide in agriculture, we obtained a chitosanolytic activity by washing the cells with concentrated sodium acetate. The optimum pH and temperature values for this enzyme were 6.0 and 60 °C, respectively. The enzymatic extract efficiently hydrolyzed various chitosans with different deacetylation degrees (DD) into small oligosaccharides. Combining mass spectrometry (ESI-Q-TOF) and high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD), we observed the formation of fully deacetylated chitooligosaccharides [fdCOS, (GlcN)2-5] and, to a lesser extent, partially acetylated chitooligosaccharides [paCOS, GlcNAc-(GlcN)1-3]. A 10 g/L solution of chitosan with 600–800 kDa and DD ≥ 90% was fully converted into oligosaccharides in 55 h. Most of the products were fdCOS: 1.6 g/L of chitobiose, 1.7 g/L of chitotriose, 5 g/L of chitotetraose and 1.4 g/L of chitopentaose.engjournal article10.1016/j.procbio.2018.07.017restricted accessQuitonesOligosacáridosBioquímicaBioquímica