A Box–Behnken design approach for the production of xylanase by Aspergillus candidus under solid state fermentation and its application in saccharification of agro residues and Parthenium hysterophorus L.

Xylanase production by indigenous Aspergillus candidus using wheat bran as a substrate under solid state fermentation was studied. Inorganic nitrogen source ammonium nitrate was found best among all the nitrogen sources tested. Physical parameters like time of incubation, temperature and moisture content were optimized using Box–Behnken design and under optimized condition maximum xylanase activity found 770 U/gds. Low amount of CMCase (77 U/gds) and FPase (26.12 U/gds) were produced concomitantly with xylanase. The crude xylanase preparation was used for saccharification of aqueous ammonia treated of various lignocellulosic materials like corn cob, wheat straw, sugar cane bagasse and Parthenium weed. Corn cob produced maximum sugar yield and further response surface method was employed to optimized saccharification yield. Under optimized condition maximum reducing sugar yield were found to be 438.47 mg/g which was found significantly high considering earlier studies available in the literature.

► First report of xylanase production under SSF using Aspergillus candidus.
► Statistical optimization was used for enzyme mediated saccharification of corn cob.
► Saccharification yield from corn cob was found significantly high.
► Saccharification potential of Parthenium plant biomass has been described.