title: Enzymatic hydrolysis optimization of microwave alkali pretreated wheat straw and ethanol production by yeast.
abstract: Microwave alkali pretreated wheat straw was used for in-house enzyme production by Aspergillusflavus and Trichodermareesei. Produced enzymes were concentrated, pooled and assessed for the hydrolysis of pretreated wheat straw. Factors affecting hydrolysis were screened out by Placket-Burman design (PBD) and most significant factors were further optimized by Box-Behnken design (BBD). Under optimum conditions, 82% efficiency in hydrolysis yield was observed. After the optimization by response surface methodology (RSM), a model was proposed to predict the optimum value confirmed by the experimental results. The concentrated enzymatic hydrolyzate was fermented for ethanol production by Saccharomyces cerevisiae, Pichia stipitis and co-culture of both. The yield of ethanol was found to be 0.48 g(p)/g(s), 0.43 g(p)/g(s) and 0.40 g(p)/g(s) by S. cerevisiae, P. stipitis and by co-culture, respectively, using concentrated enzymatic hydrolyzate. During anaerobic fermentation 42.31 μmol/mL, 36.69 μmol/mL, 43.35 μmol/mL CO(2) was released by S. cerevisiae, P. stipitis and by co-culture, respectively.
authors.affiliation: Department of Environmental Science and Engineering, Guru Jambheshwar University of Science and Technology, Hisar 125001, Haryana, India. anitasaharan@gmail.com
authors.forename: Anita
authors.initials: A
authors.lastname: Singh
authors.forename: Narsi R
authors.initials: NR
authors.lastname: Bishnoi
mesh_terms: D001231:Aspergillus flavus / Q000201:enzymology*; D001709:Biotechnology / Q000379:methods*; D002245:Carbon Dioxide / Q000378:metabolism; D002849:Chromatography, Gas; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation; D006868:Hydrolysis; D008872:Microwaves; D010843:Pichia / Q000378:metabolism; D018547:Plant Stems / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D014242:Trichoderma / Q000201:enzymology*; D014908:Triticum / Q000378:metabolism*
chemical_list: D002245:Carbon Dioxide; D000431:Ethanol