Lignin content in natural Populus variants affects sugar release

Studer, Michael Hans-Peter; DeMartini, J. D.; Davis, M. F.; Sykes, R. W.; Davison, B.; Keller, M.; Tuskan, G. A.; Wyman, C. E. (2011). Lignin content in natural Populus variants affects sugar release Proceedings of the National Academy of Sciences, 108(15), pp. 6300-6305. National Academy of Sciences 10.1073/pnas.1009252108

Text Studer2011 Lignin content in natural Populus variants affects sugar release.pdf - Published Version Restricted to registered users only Available under License Publisher holds Copyright. Download (676kB) | Request a copy

he primary obstacle to producing renewable fuels from lignocellulosic biomass is a plant's recalcitrance to releasing sugars bound in the cell wall. From a sample set of wood cores representing 1,100 individual undomesticated Populus trichocarpa trees, 47 extreme phenotypes were selected across measured lignin content and ratio of syringyl and guaiacyl units (S/G ratio). This subset was tested for total sugar release through enzymatic hydrolysis alone as well as through combined hot-water pretreatment and enzymatic hydrolysis using a high-throughput screening method. The total amount of glucan and xylan released varied widely among samples, with total sugar yields of up to 92% of the theoretical maximum. A strong negative correlation between sugar release and lignin content was only found for pretreated samples with an S/G ratio < 2.0. For higher S/G ratios, sugar release was generally higher, and the negative influence of lignin was less pronounced. When examined separately, only glucose release was correlated with lignin content and S/G ratio in this manner, whereas xylose release depended on the S/G ratio alone. For enzymatic hydrolysis without pretreatment, sugar release increased significantly with decreasing lignin content below 20%, irrespective of the S/G ratio. Furthermore, certain samples featuring average lignin content and S/G ratios exhibited exceptional sugar release. These facts suggest that factors beyond lignin and S/G ratio influence recalcitrance to sugar release and point to a critical need for deeper understanding of cell-wall structure before plants can be rationally engineered for reduced recalcitrance and efficient biofuels production.

Item Type:	Journal Article (Original Article)
Division/Institute:	School of Agricultural, Forest and Food Sciences HAFL > Resource-efficient agricultural production systems School of Agricultural, Forest and Food Sciences HAFL > Agriculture
Name:	Studer, Michael Hans-Peter0000-0003-1083-0967; DeMartini, J. D.; Davis, M. F.; Sykes, R. W.; Davison, B.; Keller, M.; Tuskan, G. A. and Wyman, C. E.
Subjects:	Q Science > Q Science (General)
ISSN:	0027-8424
Publisher:	National Academy of Sciences
Language:	English
Submitter:	Michael Hans-Peter Studer
Date Deposited:	21 Apr 2020 12:53
Last Modified:	18 Dec 2020 13:29
Publisher DOI:	10.1073/pnas.1009252108
ARBOR DOI:	10.24451/arbor.10127
URI:	https://arbor.bfh.ch/id/eprint/10127