Growing Lemna minor in agricultural wastewater and converting the duckweed biomass to ethanol
Abstract
Duckweed (Lemna minor) was grown in swine lagoon wastewater and Schenk & Hildebrandt medium with a growth rate of 3.5 and14.1 g m-2 day-1 (dry basis), respectively detected. The rapid accumulation of starch in duckweed biomass (10-36%, w/w) was triggered by nutrient starvation or growing in dark with addition of glucose. The harvested duckweed biomass (from culture in wastewater) contained 20.3% (w/w) total glucan, 32.3% (w/w) proteins, trace hemicellulose and undetectable lignin. Without prior thermal-chemical pretreatment, up to 96.2% (w/w) of glucose could be enzymatically released from both the cellulose and starch fractions of duckweed biomass. The enzymatic hydrolysates could be efficiently fermented by two yeast strains (self-flocculating yeast SPSC01 and conventional yeast ATCC 24859) with a high ethanol yield of 0.485 g g-1 (glucose).
- Publication:
-
Bioresource Technology
- Pub Date:
- November 2012
- DOI:
- 10.1016/j.biortech.2012.08.050
- Bibcode:
- 2012BiTec.124..485G
- Keywords:
-
- Duckweed;
- Lemna minor;
- Bioethanol;
- Saccharification;
- Fermentation