Development and physical characterization of alpha-glucan nanoparticles

Authors: Evans, Kervin; Skory, Christopher - Chris; Compton, David - Dave; CORMIER, RYAN - Catalent Pharma Solutions; COTE, GREG - Retired ARS Employee; Kim, Sanghoon; Appell, Michael

Submitted to: Molecules
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/19/2020
Publication Date: 8/21/2020
Citation: Evans, K.O., Skory, C.D., Compton, D.L., Cormier, R., Cote, G., Kim, S., Appell, M.D. 2020. Development and physical characterization of alpha-glucan nanoparticles. Molecules. 25(17). Article 3807. https://doi.org/10.3390/molecules25173807.
DOI: https://doi.org/10.3390/molecules25173807

Interpretive Summary: Nanoparticles are microscopic particles that are used in numerous industrial, pharmaceutical and food applications. New uses for this technology continue to expand as nanoparticles are made from unique materials. In this work, a novel enzyme from a bacterium used in food fermentation processes was utilized to produce water-insoluble biopolymers from sugar. These polysaccharides were then converted to water-soluble biodegradable nanoparticles using high-pressure homogenization. This study demonstrated that these nanoparticles were stable under acidic and basic condition, tolerated high temperatures, and showed no degradation when stored for more than 7 months at room temperature. It was also shown that these nanoparticles contained an internal region that excludes water and might be useful for encapsulation of molecules with poor water solubility. These nanoparticles have potential in agricultural, nutraceutical, and cosmeceutical applications. This work demonstrates a foundation for developing new eco-friendly materials derived from renewable agricultural materials.

Technical Abstract: alpha-Glucans enzymatically synthesized from sucrose using glucansucrase cloned from Leuconostoc mesenteroides NRRL B-1118 were found to have a glass transition temperature of approximately 80ºC. Using high-pressure homogenization (~70 MPa), the '-glucans were converted into nanoparticles of ~ 120 nm in diameter with a surface potential of ~ -3 mV. Fluorescence measurements using 1,6-diphenyl-1,3,5-hexatriene (DPH) indicate that the alpha-glucan nanoparticles have a hydrophobic core that remains intact from 10 to 85ºC. alpha-Glucan nanoparticles were found to be stable for over 220 day and able to form at three pH levels. Accelerated exposure measurements demonstrated that the alpha-glucan nanoparticles endure exposure to elevated temperatures up to 60ºC for 6 hrs intervals.