Simultaneous production of xylanase and bioactive phenolic compounds by solid state fermentation using Aureobasidium pullulans NRRL Y-2311-1
Project no. 28464 · Status: Kapanmış · 2023
Summary
<p>Solid state bioprocess is a very useful tool for simultaneous production of multiple value-added products from lignocellulosic biomass within biorefinery concept. In this study, simultaneous production of xylanase and bioactive phenolic compounds by solid state fermentation of wheat bran with <em>Aureobasidium</em> <em>pullulans </em>NRRL Y–2311–1 was carried out for the first time. Effect of various bioprocess parameters on xylanase production was elucidated. The maximum xylanase production was obtained at the fourth day of the bioprocess using distilled water as a humidifying solution at solid: liquid ratio of 1.0:1.2. Inoculation of 1 mL of seed medium was the optimum for maximum xylanase production. Among the tested nitrogen sources, (NH4)2SO4 was the best nitrogen source further stimulating xylanase production. The characterization of crude enzyme preparation studies revealed that the optimum temperature and pH for the xylanase were 50°C and pH 4.0, respectively. The crude xylanase was stable in pH range of 3.0-8.0. The SDS-PAGE pattern of the crude enzyme preparation exhibited a very complex protein profile including a protein band of 21.6 kDA which has been identified as the xylanase of <em>A</em>. <em>pullulans</em> NRRL Y–2311–1 by peptide mass fingerprinting before. The current study explored that drying method and drying temperature of the solid residue after enzyme leaching had profound effect on antioxidant properties of extracted bioactives. Hot air drying at 65°C was the most suitable option because of providing the highest phenolic content and total antioxidant capacity.</p>