Improving Production of Bioethanol from Duckweed (Landoltia punctata) by Pectinase Pretreatment

Energies

Qian Chen¹  Yanling Jin¹  Guohua Zhang¹  Yang Fang¹  Yao Xiao¹ 

[1] Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences (CAS), Chengdu 610041, China; E-Mails:

关键词: duckweed;    Landoltia punctata;    pectinase;    ethanol fermentation;    surface response design;    Saccharomyces cerevisiae;   

DOI  :  10.3390/en5083019

来源: mdpi

【 摘 要 】

Landoltia punctata, a widely distributed duckweed strain with the ability to accumulate starch, was used as a novel feedstock for bioethanol production by Saccharomyces cerevisiae. To improve ethanol production, pectinase pretreatment was used to release much more glucose from L. punctata mash and the pretreatment conditions (enzyme loading, temperature and pretreatment time) for the duckweed were optimized by using a surface response design. The results showed that maximum glucose yield was 218.64 ± 3.10 mg/g dry matter, which is a 142% increase compared to the untreated mash, with a pectinase dose of 26.54 pectin transeliminase unit/g mash at 45 °C for 300 min. Pectinase pretreatment apparently changed the ultrastructure of L. punctata, as evidenced by scanning electron microscopy analysis. Further fermentation experiments were performed and 30.8 ± 0.8 g/L of ethanol concentration, 90.04% of fermentation efficiency and 2.20 g/L^/h of productivity rate were achieved. This is the highest ethanol concentration reported to date using duckweed as the feedstock.

【 授权许可】

CC BY   
© 2012 by the authors; licensee MDPI, Basel, Switzerland.