Characterization of levan produced by a Paenibacillus sp. isolated from Brazilian crude oil

• Main Authors: Converti, A. (Author), Evtuguin, D.V (Author), Freire, R.K.B (Author), Gudiña, E.J (Author), Mendonça, C.M.N (Author), Nunes, C. (Author), Oliveira, R.C (Author), Oliveira, R.P.S (Author), Pereira, W.A (Author), Piazentin, A.C.M (Author), Rodrigues, L.R (Author), Santos, J.H.P.M (Author)
• Format: Article
• Language: English
• Published: Elsevier B.V. 2021
• Subjects: alcohol; Article; Brazilian; carbohydrate analysis; Carbohydrate Conformation; Chemical Fractionation; conformation; degree of polymerization; differential scanning calorimetry; drug industry; electrospray mass spectrometry; elemental analysis; Fourier transform infrared spectroscopy; fractionation; fructan; Fructans; fructose oligosaccharide; gas chromatography; glycoside; heat; Hot Temperature; isolation and purification; levan; Levan; metabolism; methylation; microbiology; monosaccharide; nitrogen; nonhuman; nuclear magnetic resonance; nucleotide sequence; nutraceutical; Paenibacillus; petroleum; Petroleum; Physicochemical characterization; scanning electron microscopy; structure activity relation; Structure-Activity Relationship; sucrose; temperature; thermogravimetry; Thermomechanical stability; vitrification; Vitrification; X ray diffraction
• Online Access: View Fulltext in Publisher

 A levan-type fructooligosaccharide was produced by a Paenibacillus strain isolated from Brazilian crude oil, the purity of which was 98.5% after precipitation with ethanol and dialysis. Characterization by FTIR, NMR spectroscopy, GC-FID and ESI-MS revealed that it is a mixture of linear β(2 → 6) fructosyl polymers with average degree of polymerization (DP) of 18 and branching ratio of 20. Morphological structure and physicochemical properties were investigated to assess levan microstructure, degradation temperature and thermomechanical features. Thermal Gravimetric Analysis highlighted degradation temperature of 218 °C, Differential Scanning Calorimetry (DSC) glass transition at 81.47 °C, and Dynamic Mechanical Analysis three frequency-dependent transition peaks. These peaks, corresponding to a first thermomechanical transition event at 86.60 °C related to the DSC endothermic event, a second at 170.9 °C and a third at 185.2 °C, were attributed to different glass transition temperatures of oligo and polyfructans with different DP. Levan showed high morphological versatility and technological potential for the food, nutraceutical, and pharmaceutical industries. © 2021 Elsevier B.V.