BioChem - DOS

Enhancing alfalfa conversion efficiencies for sugar recovery and ethanol production by altering lignin composition

Bioresource technology : biomass, bioenergy, biowastes, conversion technologies, biotransformations, production technologies

Dien, B.S.; Miller, D.J.; Hector, R.E.; Dixon, R.A.; Chen, F.; McCaslin, M.; Reisen, P.; Sarath, G.; Cotta, M.A.

Alfalfa (Medicago sativa L.) biomass was evaluated for biochemical conversion into ethanol using dilute-acid and ammonia pretreatments. The two alfalfa lines compared were a reduced S-lignin transgenic cultivar generated through down regulation of the caffeic acid O-methyltransferase gene and a wild-type control. Both were harvested at two maturities. All the samples had similar carbohydrate contents including a mean composition of 316g glucan and 497g total neutral carbohydrates per kg dry biomass, which corresponds to a theoretic ethanol yield of 382l/ton. Ethanol yields for alfalfa stems pretreated with dilute-acid were significantly impacted by harvest maturity and lignin composition, whereas when pretreated with dilute-ammonia, yield was solely affected by lignin composition. Use of a recombinant xylose-fermenting Saccharomyces strain, for converting the ammonia pretreated alfalfa samples, further increased ethanol yields. Ethanol yields for the xylose-fermenting yeast were 232-278l/ton and were significantly enhanced for the reduced S lignin cultivars.

2011

Elsevier Applied Science

0960-8524

102

11

pp.6479-6486

10.1016/j.biortech.2011.03.022

http://click.ndsl.kr/servlet/OpenAPIDetailView?keyValue=05787966&target=NART&cn=NART56032493

Biomass; Alfalfa; Bioethanol; Pretreatment; Lignin-modified transgenics