Simultaneous saccharification and fermentation of cassava waste for ethanol production

Document Type: Research Paper


1 Department of Botany, Alagappa Government Arts College, Karaikudi 630003, Tamilnadu, India.

2 Department of Energy Science, Alagappa University, Karaikudi 630004, Tamilnadu, India.

3 Research Centre in Botany, Thiagarajar College, Madurai 625009, Tamilnadu, India.


The efficiency of enzymatic and microbial saccharification of cassava waste for ethanol production was investigated and the effective parameters were optimized. The mixture of amylase and amyloglucosidase (AMG) resulted in a significantly higher rate of saccharification (79.6%) than the amylase alone (68.7%). Simultaneous saccharification and fermentation (SSF) yielded 6.2 g L-1 ethanol representing 64.5% of the theoretical yield. Saccharification and fermentation using pure and co-cultures of fungal isolates including Rhizopus stolonifer, Aspergillus terreus, Saccharomyces diastaticus and Zymomonas mobilis revealed that the co-culture system involving S. diastaticus and Z. mobilis was highly suitable for the bio-conversion of cassava waste into ethanol, resulting in 20.4 g L-1 in 36 h (91.3% of the theoretical yield).

Graphical Abstract

Simultaneous saccharification and fermentation of cassava waste for ethanol production


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