Optimization of Solid-state Fermentation Conditions for Production of β-mannanase with Apple Pomace by Aspergillus niger

Objective: In order to reduce the production cost of β-mannanase and make the best of apple pomace,the fermentation conditions for Aspergillus niger SL-08 to produce β-mannanase with apple pomace as raw material in solid-state fermentation were optimized.Method: Plackett-Burman design and response surface methodology were adopted to optimize the fermentation medium.Result: The mixture of apple pomace and cottonseed powder(1∶1,w/w) with 59%(w/w)initial moisture,supplemented with 2%(w/w) urea,0.1%(w/w) KH2PO4,0.2%(w/w)CaCl2 and 0.1%(w/w)MgCl2,was proved to be the optimum medium.When the test fungi were inoculated in the optimized medium and incubated at 30℃ for 48h,the activity of β-mannanase increased by 28.3% than that in the basal medium and achieved 539 u/g,which was as high as the enzyme activity obtained when the bran was used as the raw material.Conclusion: Solid-state fermentation with apple pomace as raw material by Aspergillus niger SL-08 was proved to be an effective way for both the production of β-mannanase and the comprehensive utilization of apple pomace.