Lipophilic Arginine Esters: The Gateway to Preservatives without Side Effects.

Abstract

This study hypothesized that long carbon chain cationic arginine (Arg) esters can be considered as toxicologically harmless preservatives. Arg-esters with C18 and C24 carbon chains, namely, arginine-oleate (Arg-OL) and arginine-decyltetradecanoate (Arg-DT), were synthesized. Structures were confirmed by FT-IR, 1H NMR, and mass spectroscopy. Both Arg-esters were tested regarding hydrophobicity in terms of log Poctanol/water, critical micelle concentration (CMC), biodegradability, cytotoxicity, hemolysis, and antimicrobial activity against Escherichiacoli (E. coli), Staphylococcusaureus (S. aureus), Bacillussubtilis (B. subtilis), and Enterococcusfaecalis (E. faecalis). Log Poctanol/water of arginine was raised from -1.9 to 0.3 and 0.6 due to the attachment of C18 and C24 carbon chains, respectively. The critical micelle concentration of Arg-OL and Arg-DT was 0.52 and 0.013 mM, respectively. Both Arg-esters were biodegradable by porcine pancreatic lipase. In comparison to the well-established antimicrobials, benzalkonium chloride (BAC) and cetrimide, Arg-esters showed significantly less cytotoxic and hemolytic activity. Both esters exhibited pronounced antimicrobial properties against Gram-positive and Gram-negative bacteria comparable to that of BAC and cetrimide. The minimum inhibitory concentration (MIC) of Arg-esters was <50 μg mL-1 against all tested microbes. Overall, results showed a high potential of Arg-esters with long carbon chains as toxicologically harmless novel preservatives.

• Authors: Iram Shahzadi, Aamir Jalil, Mulazim Hussain Asim, Andrea Hupfauf, Ronald Gust, Philipp Alexander Nelles, Ludwig Knabl, Andreas Bernkop-Schnürch
• Journal: Molecular pharmaceutics (Mol Pharm) Vol. 17 Issue 8 Pg. 3129-3139 (08 03 2020) ISSN: 1543-8392 [Electronic] United States
• PMID: 32598849 (Publication Type: Journal Article)

Chemical References

• Anti-Bacterial Agents
• Benzalkonium Compounds
• Biodegradable Plastics
• Esters
• Micelles
• Preservatives, Pharmaceutical
• Carbon
• Arginine
• Lipase
• Cetrimonium

Topics

• Animals
• Anti-Bacterial Agents (chemistry, pharmacology)
• Arginine (chemistry)
• Bacteria (drug effects)
• Benzalkonium Compounds (chemistry)
• Biodegradable Plastics (chemistry)
• Caco-2 Cells
• Carbon (chemistry)
• Cell Line, Tumor
• Cetrimonium (chemistry)
• Esters (chemistry)
• Hemolysis (drug effects)
• Humans
• Lipase (chemistry)
• Micelles
• Preservatives, Pharmaceutical (chemistry)
• Spectroscopy, Fourier Transform Infrared (methods)
• Swine