Aqueous two-phase partitioning and characterization of xylanase produced by Streptomyces geysiriensis from low cost lignocellulosic substrates
| Autor: | Shanmugam Poornima, Vivekanandhan Karthik, Natchimuthu Karmegam, R. Subbaiya, Palanisamy Divya |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
0106 biological sciences
0301 basic medicine Metal ions in aqueous solution Bioengineering engineering.material Lignin 01 natural sciences Applied Microbiology and Biotechnology 03 medical and health sciences Bioreactors 010608 biotechnology Bioreactor Endo-1 4-beta Xylanases Aqueous solution Chromatography Bran Chemistry Pulp (paper) Temperature Water Hydrogen-Ion Concentration Streptomyces Kinetics 030104 developmental biology Solid-state fermentation Fermentation Costs and Cost Analysis engineering Xylanase Xylans Biotechnology |
| Zdroj: | Journal of Bioscience and Bioengineering. 130:571-576 |
| ISSN: | 1389-1723 |
| DOI: | 10.1016/j.jbiosc.2020.07.008 |
| Popis: | Microbial production of xylanase is gaining the commercial importance, due to its wide range of applications from paper and pulp to food and feed industries. Streptomyces geysiriensis was used for the production of extracellular xylanase from lignocellulosic substrates such as rice bran and saw dust, under solid-state fermentation. The influence of pH, temperature and incubation period for the maximum production of xylanase was investigated with 1:2 (w/v) of substrate to moisture ratio at 100 rpm shaking conditions. The maximum production was recorded after 5 days of fermentation with pH 8.0 at 40 °C. The scale-up was done based on the results of optimized parameters using 3 L Applikon autoclavable bioreactor with maximum yield of 186 U/ml after 4 days of fermentation. Extracellular xylanase was separated by partitioning in aqueous two-phase system consisting of 20% polyethylene glycol 6000 and 12% K2HPO4 with maximum yield of 93.97%. The investigation of the effect of pH and temperature and its incubation time showed that xylanase was retained its activity in a pH range of 6.5–8.5, with thermal stability from 20 °C to 60 °C up to 180 min. The presence of metal ions was found to inhibit the activity of xylanase especially Cu2+ and Zn2+. Xylanase was stable both at 4 °C and room temperature (35 °C) for 30 and 9 days respectively. The kinetic parameters Km (0.48 mg/ml) and Vmax (8.33 U/mg) were determined using birchwood xylan as substrate. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect