Creating new water-soluble Iso- and n-fatty acid arginate hydrochloride with antimicrobial properties

Authors: ZHANG, JIANWEI - Non ARS Employee; HUANG, KUN - Non ARS Employee; Fan, Xuetong; Strahan, Gary; NUNEZ, ALBERTO - Retired ARS Employee; Sarker, Majher; Ngo, Helen

Submitted to: European Journal of Lipid Science and Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/29/2023
Publication Date: 7/23/2023
Citation: Zhang, J., Huang, K., Fan, X., Strahan, G.D., Nunez, A., Sarker, M.I., Lew, H.N. 2023. Creating new water-soluble Iso- and n-fatty acid arginate hydrochloride with antimicrobial properties. European Journal of Lipid Science and Technology. https://doi.org/10.1002/ejlt.202300012.
DOI: https://doi.org/10.1002/ejlt.202300012

Interpretive Summary: Preservatives derived from parabens are heavily used in food and non-food processes; however, many have been found to have a negative health impact on humans and the environment. With this increasing issue, many natural-based antimicrobials have been developed to replace paraben preservatives as they have higher antibacterial activity and are safer for the environment. Considering these aspects, efforts were initiated to explore the synthesis of natural-based products from two streams of natural feedstocks (lipid and amino acid). The resulting products contain fatty acid backbone and amino acid functional groups, namely fatty acid arginate. Furthermore, they have bioactive functionality to inhibit bacteria at very low doses of exposures. These exciting results show that the developed natural-based products can potentially be excellent paraben-free products for food and non-food applications.

Technical Abstract: The negative impact of the synthetic antimicrobials and the overuse of antibiotics have caused global concern, which necessitates the development of a new form of antimicrobials that are derived from natural compounds. In this study, the synthetic route of producing water soluble iso-fatty acid arginate hydrochloride derivatives is investigated by introducing C18-branched (iso-) chain and other linear- (n-) chain fatty acids to the amino acid “arginine” molecules. The two-step synthesis is straightforward and provides an efficient 91%, 88%, and 76% product yield for ethyl n-lauroyl arginate hydrochloride, ethyl n-oleoyl arginate hydrochloride, and ethyl iso-oleoyl arginate hydrochloride, respectively. ATR-FT-IR, NMR, and LC-MS-Q-TOF techniques are used to thoroughly characterize the products. The antimicrobial characteristic of the synthesized ethyl n-lauroyl arginate (LAE) shows a similar activity against both Gram+ and Gram- bacteria as the commercial LAE product. However, its analogs are found to have antimicrobial properties primarily against Gram+ bacteria.