Production of high activity Aspergillus nigerBCC4525 β-mannanase in Pichia pastorisand its application for mannooligosaccharides production from biomass hydrolysis

Autor: Harnpicharnchai, Piyanun, Pinngoen, Waraporn, Teanngam, Wanwisa, Sornlake, Warasirin, Sae-Tang, Kittapong, Manitchotpisit, Pennapa, Tanapongpipat, Sutipa
Zdroj: Bioscience, Biotechnology, and Biochemistry; December 2016, Vol. 80 Issue: 12 p2298-2305, 8p
Abstrakt: A cDNA encoding β-mannanase was cloned from Aspergillus nigerBCC4525 and expressed in Pichia pastorisKM71. The secreted enzyme hydrolyzed locust bean gum substrate with very high activity (1625 U/mL) and a relatively high kcat/Km(461 mg−1s−1 mL). The enzyme is thermophilic and thermostable with an optimal temperature of 70 °C and 40% retention of endo-β-1,4-mannanase activity after preincubation at 70 °C. In addition, the enzyme exhibited broad pH stability with an optimal pH of 5.5. The recombinant enzyme hydrolyzes low-cost biomass, including palm kernel meal (PKM) and copra meal, to produce mannooligosaccharides, which is used as prebiotics to promote the growth of beneficial microflora in animals. An in vitrodigestibility test simulating the gastrointestinal tract system of broilers suggested that the recombinant β-mannanase could effectively liberate reducing sugars from PKM-containing diet. These characteristics render this enzyme suitable for utilization as a feed additive to improve animal performance.
Databáze: Supplemental Index