Effect of alkaline pretreatments on the enzymatic hydrolysis of wheat straw

  • Nikoleta Kontogianni
  • Elli Maria Barampouti
  • Sofia Mai
  • Dimitris Malamis
  • Maria LoizidouEmail author
Advances & Prospects in the field of Waste Management


Lignocellulosic materials are mainly consisted of lignin, cellulose, and hemicellulose. Lignin is recognized as the main obstacle for the enzymatic saccharification of cellulose towards the fermentable sugars’ production. Hence, the removal of lignin from the lignocellulosic feedstock is beneficial for reducing the recalcitrance of lignocellulose for enzymatic attack. For this purpose, various different alkaline pretreatments were examined in order to study their effect on the enzymatic saccharification of wheat straw, as a typical lignocellulosic material. Results revealed that the alkaline pretreatments promoted delignification reactions. Regarding the removal of lignin, the most efficient pretreatments were alkaline treatment with hydrogen peroxide 10% and NaOH 2% autoclave with delignification efficiencies of 89.60% and 84.86% respectively. X-ray diffraction analysis was performed to enlighten the structural changes of raw and pretreated materials. The higher the delignification of the raw material, the higher the conversion of cellulose during enzymatic saccharification. In all cases after enzymatic saccharification, the cellulosic conversion was much higher (32–77%) than the untreated wheat straw (8.6%). After undergoing alkaline peroxide 10% pretreatment and cellulase treatment, 99% of the initial raw straw was eventually solubilized. Thus, wheat straw could be considered as an ideal material for the production of glucose with proper pretreatments and effective enzymatic hydrolysis.


Agro-residues Alkaline peroxide Cellulases Crystallinity Delignification efficiency Lignin 


Funding information

The authors acknowledge funding through European Horizon 2020 NoAW (No Agro Waste, Grant no. 688338) project for supporting this work.


  1. Akhtar MS, Saleem M, Akhtar MW (2001) Saccharification of lignocellulosic materials by the cellulases of bacillus subtilis. Int J Agric Biol 3(2):99–202Google Scholar
  2. Asghar U, Irfan M, Iram M, Huma Z, Nelofer R, Nadeem M, Syed Q (2015) Effect of alkaline pretreatment on delignification of wheat straw. Nat Prod Res 29(2):125–131. CrossRefGoogle Scholar
  3. Bolado-Rodríguez S, Toquero C, Martín-Juárez J, Travaini R, García-Encina PA (2016) Effect of thermal, acid, alkaline and alkaline peroxide pretreatments on the biochemical methane potential and kinetics of the anaerobic digestion of wheat straw and sugarcane bagasse. Bioresour Technol 201:182–190. CrossRefGoogle Scholar
  4. Chaturvedi V, Verma P (2013) An overview of key pretreatment processes employed for bioconversion of lignocellulosic biomass into biofuels and value-added products. 3 Biotech 3(5):415–431. CrossRefGoogle Scholar
  5. Feng L, Qin L, Liu ZH, Dong CY, Li BZ, Yuan YJ (2014) Combined severity during pretreatment chemical and temperature on the saccharification of wheat straw using acids and alkalis of differing strength. BioResour 9(1):24–38. CrossRefGoogle Scholar
  6. Gould JM (1984) Alkaline peroxide delignification of agricultural residues to enhance enzymatic saccharification. Biotechnol Bioeng 26(1):46–52. CrossRefGoogle Scholar
  7. Haque MA, Barman DN, Kang TH, Kim MK, Kim J, Kim H, Yun HD (2012) Effect of dilute alkali on structural features and enzymatic hydrolysis of barley straw (Hordeum vulgare) at boiling temperature with low residence time. J Microbiol Biotechnol 22(12):1681–1691. CrossRefGoogle Scholar
  8. Ho MC, Ong VZ, Wu TY (2019) Potential use of alkaline hydrogen peroxide in lignocellulosic biomass pretreatment and valorization – a review. Renew Sust Energ Rev 112:75–86. CrossRefGoogle Scholar
  9. Hou XD, Feng GJ, Ye M, Huang CM, Zhang Y (2017) Significantly enhanced enzymatic hydrolysis of rice straw via a high-performance two-stage deep eutectic solvents synergistic pretreatment. Bioresour Technol 238:139–146. CrossRefGoogle Scholar
  10. Jaisamut K, Paulová L, Patáková P, Kotúčová S, Rychtera M (2016) Effect of sodium sulfite on acid pretreatment of wheat straw with respect to its final conversion to ethanol. Biomass Bioenergy 95:1–7. CrossRefGoogle Scholar
  11. Karimi K, Taherzadeh MJ (2016) A critical review of analytical methods in pretreatment of lignocelluloses: composition, imaging, and crystallinity. Bioresour Technol 200:1008–1018. CrossRefGoogle Scholar
  12. Rahikainen JL, Martin-Sampedro R, Heikkinen H, Rovio S, Marjamaa K, Tamminen T, Kruus K (2013) Inhibitory effect of lignin during cellulose bioconversion: the effect of lignin chemistry on non-productive enzyme adsorption. Bioresour Technol 133:270–278. CrossRefGoogle Scholar
  13. Sanchez O, Sierra R, Almeciga-Diaz CJ (2011) Delignification process of agro-industrial wastes an alternative to obtain fermentable carbohydrates for producing fuel. In: Manzanera M (ed) Alternative Fuel. Rijeka, InTech, pp 111–154Google Scholar
  14. Segal L, Creely JJ, Martin AE, Conrad CM (1959) An empirical method for estimating the degree of crystallinity of native cellulose using the x-ray diffractometer. Text Res J 29(10):786–794. CrossRefGoogle Scholar
  15. Sluiter A, Hames B, Ruiz R, Scarlata C, Sluiter J, Templeton D, Nrel DC (2008) Determination of structural carbohydrates and lignin in biomass determination of structural carbohydrates and lignin in biomass. Lab Anal Proceed 1617:1–16Google Scholar
  16. Solarte-Toro JC, Chacón-Pérez Y, Cardona-Alzate CA (2018) Evaluation of biogas and syngas as energy vectors for heat and power generation using lignocellulosic biomass as raw material. Electron J Biotechnol 33:52–62. CrossRefGoogle Scholar
  17. Toquero C, Bolado S (2014) Effect of four pretreatments on enzymatic hydrolysis and ethanol fermentation of wheat straw. Influence of inhibitors and washing. Bioresour Technol 157:68–76. CrossRefGoogle Scholar
  18. Tsegaye B, Balomajumder C, Roy P (2018) Biodegradation of wheat straw by Ochrobactrum oryzae BMP03 and Bacillus sp. BMP01 bacteria to enhance biofuel production by increasing total reducing sugars yield. Environ Sci Pollut R 30:30585–30596. CrossRefGoogle Scholar
  19. Vasmara C, Cianchetta S, Marchetti R, Galletti S (2017) Biogas production from wheat straw pre-treated with hydrolytic enzymes or sodium hydroxide. Environ Eng Manag J 16(8):1827–1836. CrossRefGoogle Scholar
  20. Xin L, Guo Z, Xiao X, Peng C, Zeng P, Feng W, Xu W (2019) Feasibility of anaerobic digestion on the release of biogas and heavy metals from rice straw pretreated with sodium hydroxide. Environ Sci Pollut R 19:19434–19444. CrossRefGoogle Scholar
  21. Xu GC, Ding JC, Han RZ, Dong JJ, Ni Y (2016) Enhancing cellulose accessibility of corn stover by deep eutectic solvent pretreatment for butanol fermentation. Bioresour Technol 203:364–369. CrossRefGoogle Scholar
  22. Yang Q, Pan X (2016) Correlation between lignin physicochemical properties and inhibition to enzymatic hydrolysis of cellulose. Biotechnol Bioeng 113(6):1213–1224. CrossRefGoogle Scholar
  23. Yu G, Afzal W, Yang F, Padmanabhan S, Liu Z, Xie H, Shafy M, Bell A, Prausnitz J (2014) Pretreatment of Miscanthus × giganteus using aqueous ammonia with hydrogen peroxide to increase enzymatic hydrolysis to sugars. J Chem Technol Biotechnol 89(5):698–706. CrossRefGoogle Scholar
  24. Zhao X, Cheng K, Liu D (2009) Organosolv pretreatment of lignocellulosic biomass for enzymatic hydrolysis. Appl Microbiol Biotechnol 82(5):815–827. CrossRefGoogle Scholar
  25. Zhao Z, Chen X, Ali MF, Abdeltawab AA, Yakout SM, Yu G (2018) Pretreatment of wheat straw using basic ethanolamine-based deep eutectic solvents for improving enzymatic hydrolysis. Bioresour Technol 263:325–333. CrossRefGoogle Scholar
  26. Zheng Q, Zhou T, Wang Y, Cao X, Wu S, Zhao M, Guan X (2018a) Pretreatment of wheat straw leads to structural changes and improved enzymatic hydrolysis. Sci Rep 8(1).
  27. Zheng Q, Zhou T, Wang Y, Cao X, Wu S, Zhao M, Wang H, Xu M, Zheng B, Guan X (2018b) Pretreatment of wheat straw leads to structural changes and improved enzymatic hydrolysis. Sci Rep 8(1):1321–1330. CrossRefGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.School of Chemical Engineering, Unit of Environmental Science & TechnologyNational Technical University of AthensAthensGreece

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