Green coconut mesocarp pretreated by an alkaline process as raw material for bioethanol production

Bioresour Technol. 2016 Sep:216:744-53. doi: 10.1016/j.biortech.2016.05.105. Epub 2016 May 31.

Abstract

Cocos nucifera L., coconut, is a palm of high importance in the food industry, but a considerable part of the biomass is inedible. In this study, the pretreatment and saccharification parameters NaOH solution, pretreatment duration and enzyme load were evaluated for the production of hydrolysates from green coconut mesocarp using 18% (w/v) total solids (TS). Hydrolysates were not detoxified in order to preserve sugars solubilized during the pretreatment. Reduction of enzyme load from 15 to 7.5 filter paper cellulase unit (FPU)/g of biomass has little effect on the final ethanol titer. With optimized pretreatment and saccharification, hydrolysates with more than 7% (w/v) sugars were produced in 48h. Fermentation of the hydrolysate using industrial Saccharomyces cerevisiae strains produced 3.73% (v/v) ethanol. Our results showed a simple pretreatment condition with a high-solid load of biomass followed by saccharification and fermentation of undetoxified coconut mesocarp hydrolysates to produce ethanol with high titer.

Keywords: Alkaline pretreatment; Green coconut; High-solid load; Mesocarp; Non-detoxified hydrolysate; Second-generation bioethanol.

MeSH terms

  • Biofuels*
  • Biomass
  • Biotechnology / methods*
  • Carbohydrate Metabolism / drug effects
  • Cocos / anatomy & histology*
  • Cocos / drug effects*
  • Enzymes / metabolism
  • Ethanol / metabolism*
  • Fermentation / drug effects
  • Hydrolysis
  • Powders
  • Saccharomyces cerevisiae / drug effects
  • Saccharomyces cerevisiae / metabolism
  • Sodium Hydroxide / pharmacology*
  • Time Factors

Substances

  • Biofuels
  • Enzymes
  • Powders
  • Ethanol
  • Sodium Hydroxide