Research Project: Bioproducts and Biopolymers from Agricultural Feedstocks

Location: Bioproducts Research

2023 Annual Report

Objectives
Objective 1 encompasses processing technologies primarily for cellulosic feedstocks including hemp, a potential new specialty crop in the U.S. Research on objective 1 will focus on fiber-based packaging, particularly insulative and/or cushioning foam packaging and nanofiber films and composites. Objective 2 encompasses a broader range of feedstocks and includes starches and other carbohydrates beyond starch and cellulose as well as polyhydroxyalkanoates that are produced by bacteria. The primary objective is to utilize renewable polymers that are degradable in both garden compost and marine environments to make bioproducts designed for single-use food and packaging items. Objective 3 focuses on sustainable solutions for chemical products, particularly antibiotics, that are a growing health or environmental concern. The focus will be to use small molecules that bind or associate at critical concentrations to form active complexes with specific functions. Below the critical concentrations, the active complexes dissociate into benign molecules. Objective 1: Enable new technologies to manufacture fiber/nanofiber-based bioproducts. • Sub-objective 1A: Enable new technologies for making fiber-based foam products with moisture and grease/oil resistance. • Sub-objective 1B: Create consumer products utilizing hemp fiber. Objective 2: Enable new technologies for biopolymers and their blends. • Sub-objective 2A: Develop plastics and composites for consumer products that are readily degraded in marine and soil environments. • Sub-objective 2B: Develop microorganisms for novel biopolymer production. • Sub-objective 2C: Develop new technologies to process biopolymers into industrially-relevant products. Objective 3: Develop bioactive materials that are designed to minimize ecotoxicity and biocide resistance.

Approach
Hypothesis 1A: Fiber-based materials can be made into rigid, insulative foam products or non-foam composites with moisture and grease/oil resistance. Rigid foam samples will be made with agricultural fibers, foaming agent, and sizing agents. The rigid foam will be characterized by testing the mechanical and thermal properties of the foam. If the use of agricultural fibers is unsuccessful or too expensive, kraft fiber from wood pulp will be used in the study. Hypothesis 1B: The hypothesis statement will be provided by the scientist who fills the vacant position in the CRIS. Biomass left over from CBD extraction from various industrial hemp cultivars will be pulped and used as a source of nanofibers. Water soluble film formulations will be provided by our CRADA partner and treated with nanofibers to evaluate their effect on mechanical properties. If nanofibers from hemp do not desired properties, biomass resources provided by our cooperators from Brazil. Hypothesis 2A: Marine degradable polymers and composites can be processed into bioproducts including films, foams, and molded articles. We intend to promote crystallization of thermoplastic starch (TPS) during and after extrusion and molding as a means of enhancing moisture resistance and improving strength without reverting to chemical modification or blending. Commercial starches from various agricultural sources and with varying amylose:amylopectin ratios will be evaluated and formed into TPS using twin-screw extrusion. Blends of TPS and wood fiber, cellulose nanocrystals/nanofibrillar cellulose from hemp or corn stover will be prepared, processed by extrusion and/or film blowing, and characterized. Other biopolymers or mineral additives will be used in formulations if the properties of TSP are not acceptable. Hypothesis 2B: Microorganisms that use methane (methanotrophs) or other carbon sources (Bacillus subtilis) can be engineered to improve production processes and generate valuable biopolymer additives. We will use overexpression of targeted proteins to increase cell hydrophobicity in methanotrophs. If this approach is unsuccessful, the membrane proteins that target proteins regulate will also be singled out to change their expression. Hypothesis 2C: Active nutritional supplement can be produced at large scale by Bacillus megaterium.: B. megaterium strains within our own inventory will be used to produce poly-3-hydroxybutyrate (P(3HB)) trimers as active nutritional supplements. If insufficient quantities of 3HB trimer are produced, another strategy would be to isolate fungal or bacterial depolymerases for their ability to release trimers from P(3HB). Hypothesis 3: Judicious use of reversible actives (e.g. antimicrobials) will minimize negative human health effects, ecotoxicity and biocide resistance. We will incorporate reversible bonds in traditionally persistent chemicals such as cationic guanylhydrazones to minimize environmental toxicity and biocide resistance. If activity is affected by anionic additives, we will utilize hydroxamic acids.

Progress Report
This report documents fiscal year (FY23) progress for project 2030-41000-067-000D, titled, “Bioproducts and Biopolymers from Agricultural Feedstocks”. In support of Objective 1, ARS researchers in Albany, California, developed fiber foam technology for making molded panels as a potential replacement for plastic foam used in billions of packages shipped in the United States each year. Two patent applications were prepared from the invention disclosures submitted the previous fiscal year. In addition, two manuscripts were submitted on two important advancements of the fiber foam technology. The first advancement was a compression molding process for making fiber foam panels and the second advancement detailed the use of paperboard reinforcing elements that were embedded in the foam to increase the compression strength. The results of this research demonstrated that foam composites could be made that were comparable in many aspects to polystyrene foam commonly used in internal packaging. The fiber foam had good insulative properties, low density, excellent strength, and was compostable/renewable. The Cooperative Research and Development Agreement with our industrial partner ended during the shutdown of our laboratory due to COVID restrictions. Despite having no formal agreement, our former industrial partner has assembled a research team that is working towards building a pilot scale production line with the intent of commercializing the fiber foam technology. In support of Objective 2, ARS researchers produced biodegradable biopolymers from two agricultural waste feedstocks. Globally, over 30 billion liters of biodiesel are produced annually resulting in approximately 3 billion liters of waste glycerol. We screened bacteria from publicly available culture repositories, including the ARS (NRRL) Culture Collection, and demonstrated that many could produce biopolymers when using glycerol as the sole carbon source. Bacterial strains were identified that were capable of accumulating high levels of polymer at different rates and yields. In another example, bacteria were grown on various waste oils. Depending on the substrate used, the polymers had very different physical attributes including some which were strongly adhesive and might be utilized as biodegradable sticker components. In support of Objective 3, reversible active ingredients compositions were developed and tested as antibiotic-alternatives and food processing aids. In-vivo treatments for digital dermatitis in sheep were invented and evaluated in collaboration with ARS researchers in Ames, Iowa. These and other promising results led to a Material Transfer Agreement with Zinpro, which tested efficacy on-farm, and a CRADA with an ARS collaborator, to use the actives to reduce foodborne toxins.

Accomplishments
1. Paperboard reinforcing elements improve the strength of fiber composite foam. Plastic foam is used extensively as internal packing/cushioning material in many of the 21 billion packages shipped throughout the United States each year. The large majority of packaging foams end up in landfills, but significant amounts escape as litter in the landscape and ocean environments. In a coordinated effort, ARS researchers in Albany, California, collaborated with researchers at the Brazilian Agricultural Research Corporation (EMBRAPA) in Lavras, Brazil, in demonstrating the use of starch and paperboard in making composite foam panels. The foam composites were lightweight, insulative, biodegradable, and had strength similar to polystyrene packaging foam. The results of this research show that plant-based materials could be used as a sustainable, renewable, and environmentally friendly alternative to single-use plastic foam packaging.

2. Sodium dodecyl sulfate and sodium chloride facilitate drying and redispersion of microfibrillated cellulose. Microfibrillated cellulose (MFC) is made from plant fiber and has unique properties and commercial potential due to its extremely small size and high surface area. MFC is typically made in an aqueous environment and tends to agglomerate when dried making it lose its unique properties. In a coordinated effort, ARS researchers from Albany, California, and scientists in Lavras, Brazil, and Raleigh, North Carolina, showed that when MFC was dried in the presence of sodium dodecyl sulfate or sodium chloride, it could be redispersed much more efficiently in aqueous solutions and make superior films. This research will help in efforts to better utilize MFC in products and improve commercial viability.

3. Compression molded fiber foam. Fiber foam is a new material that could help replace plastic products, but it cannot be molded using traditional equipment designed for plastics. ARS researchers in Albany, California, have developed a compression molding process for molding fiber foam into finished products. The compression molding method produces a foam with a smooth, attractive skin while preserving the foam structure of the interior. Molded foam products with different densities and strength were produced. These renewable products could be used in packaging and other products currently made with plastic foam.

Review Publications
Glenn, G.M., Orts, W.J., Klamczynski, A.P., Shogren, R., Hart-Cooper, W.M., Wood, D.F., Lee, C.C., Chiou, B. 2023. Compression molded cellulose fiber foams. Cellulose. 30:3489-3503. https://doi.org/10.1007/s10570-023-05111-0.
Patterson, G.D., McManus, J.D., Orts, W.J., Hsieh, Y. 2023. Protonation of surface carboxyls on rice straw cellulose nanofibrils: Effect on the aerogel structure, modulus, strength, and wet resiliency. Biomacromolecules. 24(5):2052-2062. https://doi.org/10.1021/acs.biomac.2c01478.
Placido, D., McMahan, C.M., Lee, C.C. 2022. Wounding and cold stress increase resin and rubber production of Parthenium argentatum cultivar G711. Industrial Crops and Products. 193. Article 116174. https://doi.org/10.1016/j.indcrop.2022.116174.
Rossomme, E.C., Hart-Cooper, W.M., Orts, W.J., McMahan, C.M., Head-Gordon, M. 2023. Computational studies of rubber ozonation explain the effectiveness of 6PPD as an antidegradant and the mechanism of its quinone formation. Environmental Science and Technology. 57(13):5216-5230. https://doi.org/10.1021/acs.est.2c08717.
Lou, L., Bilbao-Sainz, C., Wood, D.F., Rubinsky, B. 2023. Temperature controlled cryoprinting of food for dysphagia patients. Innovative Food Science and Emerging Technologies. 86. Article 103362. https://doi.org/10.1016/j.ifset.2023.103362.
Torres, L.F., McCaffrey, Z., Williams, T.G., Wood, D.F., Orts, W.J., McMahan, C.M. 2023. Evidence of silane coupling in torrefied agro-industrial residue-filled poly(styrene-co-butadiene) rubber compounds. Journal of Applied Polymer Science. 140(12). Article e53646. https://doi.org/10.1002/app.53646.
Bilbao-Sainz, C., Chiou, B., Takeoka, G.R., Williams, T.G., Wood, D.F., Powell-Palm, M., Rubinsky, B., McHugh, T.H. 2022. Novel isochoric cold storage with isochoric impregnation to improve postharvest quality of sweet cherry. ACS Food Science and Technology. 2(10):1558-1564. https://doi.org/10.1021/acsfoodscitech.2c00194.
Bilbao-Sainz, C., Chiou, B., Takeoka, G.R., Williams, T.G., Wood, D.F., Powell-Palm, M., Rubinsky, B., Wu, V.C., McHugh, T.H. 2022. Isochoric freezing and isochoric supercooling as innovative postharvest technologies for pomegranate preservation. Postharvest Biology and Technology. 194. Article 112072. https://doi.org/10.1016/j.postharvbio.2022.112072.
McCaffrey, Z., Cal, A., Torres, L.F., Chiou, B., Wood, D.F., Williams, T.G., Orts, W.J. 2022. Polyhydroxybutyrate rice hull and torrefied rice hull biocomposites. Polymers. 14(18). Article 3882. https://doi.org/10.3390/polym14183882.
Debevc, S., Weldekidan, H., Snowdon, M., Vivekanandhan, S., Wood, D.F., Misra, M., Mohanty, A. 2022. Valorization of almond shell biomass to biocarbon materials: Influence of pyrolysis temperature on their physicochemical and electrical conductivity. Carbon Trends. 9. Article 100214. https://doi.org/10.1016/j.cartre.2022.100214.
Chen, G.Q., Ponciano, G.P., Dong, C., Dong, N., Johnson, K., Bolton, T.T., Williams, T.G., Wood, D.F., Placido, D.F., McMahan, C.M., Dyer, J.M. 2023. Overexpressing an Arabidopsis SEIPIN1 reduces rubber particle size in guayule. Industrial Crops and Products. 195. Article 116410. https://doi.org/10.1016/j.indcrop.2023.116410.
Wang, Y., Hart-Cooper, W.M., Rasooly, R., Carter, M.Q., Orts, W.J., Gu, Y.Q., He, X. 2022. Effect of an eco-friendly cuminaldehyde guanylhydrazone disinfectant on Shiga toxin production and global transcription of Escherichia coli. Toxins. 14(11). Article 752. https://doi.org/10.3390/toxins14110752.
Bilbao-Sainz, C., Chiou, B., Takeoka, G.R., Williams, T.G., Wood, D.F., Powell-Palm, M., Rubinsky, B., McHugh, T.H. 2022. Novel isochoric impregnation to develop high-quality and nutritionally fortified plant materials (apples and sweet potatoes). Journal of Food Science. 87(11):4796-4807. https://doi.org/10.1111/1750-3841.16332.