Title: Nanomechanics and Raman Spectroscopy of in Situ Native Carbohydrate Storage Granules for Enhancing Starch Quality and Lignocellulosic Biomass Production

Abstract

Alternative energy strategies based on plant biomass-derived bioenergy and biofuels rely on understanding and optimization of plant structure, chemistry, and performance. Starch, a constitutive element of all green plants, is important to food, biofuels, and industrial applications. Models of carbohydrate storage granules are highly heterogeneous in representing morphology and structure, though a deeper understanding of the role of structure in functional behavior is emerging. A better understanding of the in situ nanoscale properties of native granules is needed to help improve the starch quality in food crops as well as optimize lignocellulosic biomass production in perennial nonfood crops. Here, we present a new technique called soft mechanical nano-ablation (sMNA) for accessing the interior of the granules without compromising the inner nanostructure. We then explore the nanomechanics of granules within the ray parenchyma cells of Populus xylem, a desirable woody biofuel feedstock. The employed soft outer layer nanoablation and atomic force microscopy reveal that the inner structure comprises 156 nm blocklets arranged in a semicrystalline organization. The nanomechanical properties of the inner and outer structures of a single starch granule are measured and found to exhibit large variations, changing by a factor of 3 in Young’s modulus and a factor ofmore » 2 in viscoplastic index. These findings demonstrate how the introduced approach facilitates studies of structure–function relationships among starch granules and more complex secondary cell wall features as they relate to plant performance.« less

Authors:

Farahi, Rubye H. ^[1]; Lereu, Aude L.  ^[2];

• Search DOE PAGES for author "Lereu, Aude L."
• Search DOE PAGES for ORCID "0000-0001-7390-7832"

Charrier, Anne M.  ^[3];

• Search DOE PAGES for author "Charrier, Anne M."
• Search DOE PAGES for ORCID "0000-0002-0205-1341"

Kalluri, Udaya C. ^[4]; Davison, Brian H. ^[5]; Passian, Ali  ^[6]

• Search DOE PAGES for author "Passian, Ali"
• Search DOE PAGES for ORCID "0000-0002-4736-4157"

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+ Show Author Affiliations

1. Computational Sciences and Engineering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
2. Aix Marseille University, CNRS, Centrale Marseille, Institut Fresnel, Marseille 13397, France
3. Aix Marseille University, CNRS, CINaM, Marseille 13288, France
4. BioEnergy Science Center, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
5. BioEnergy Science Center, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States, Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
6. Computational Sciences and Engineering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States, BioEnergy Science Center, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States, Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States, Department of Physics, University of Tennessee, Knoxville, Tennessee 37996, United States

Publication Date:

Thu Feb 06 00:00:00 EST 2020

Research Org.:

Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Biological and Environmental Research (BER); USDOE Office of Science (SC), Basic Energy Sciences (BES)

OSTI Identifier:

1598065

Alternate Identifier(s):

OSTI ID: 1607306

Grant/Contract Number:  

AC05-00OR22725

Resource Type:

Published Article

Journal Name:

ACS Omega

Additional Journal Information:

Journal Name: ACS Omega Journal Volume: 5 Journal Issue: 6; Journal ID: ISSN 2470-1343

Publisher:

American Chemical Society (ACS)

Country of Publication:

United States

Language:

English

Subject:

09 BIOMASS FUELS