Preparation, characterization, and surface and biological properties of N‐stearoyl amino acids

Abstract

Several lipoamino acids were synthesized, in which n-octadecanoic acid (stearic acid) was coupled with the α-amino group of an amino acid. The products were characterized and their identities confirmed by advanced analytical techniques like Fourier transform infrared, 1 H nuclear magnetic resonance spectroscopy, and differential scanning calorimetry. Their surface properties, such as critical micelle concentration (CMC) and foaming properties, biodegradability, and antimicrobial activity were also evaluated. The N-stearoyl amino acids (NSA) had low CMC values, and some of them showed good foaming properties. They were screened for antimicrobial activity against the gram-positive bacteria Staphylococcus aureus, Micrococcus luteus, and Bacillus cerceus, the gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa, and the yeast Candida albicans. All the compounds inhibited at least one of these organisms. N-Stearoyl proline was the most effective, the order of antimicrobial activity being aromatic NSA > acidic NSA > basic NSA. However, the effective inhibition by all the compounds indicates the desirability of more thorough investigation and suggests that some of these compounds may have potential utility as biostatic additives in commercial products. All NSA are highly biodegradable and can readily be removed under conditions of normal secondary sewage treatment.Paper no. J9653 in JAOCS 78, 897-902 (September 2001).

Identification of endogenous acyl amino acids based on a targeted lipidomics approach

“…Similar phenomenon occurred to the dipeptide of leucine and aspartic acid in which aspartic acid is on the C-terminal position ( 37 ). The mechanism is shown in the supplementary data.…”

Synthesis of Novel Lipoamino Acid Conjugates of Sapienic Acid and Evaluation of Their Cytotoxicity Activities

“…Proton NMR spectral data showed peaks corresponding to protons of corresponding to double bond and protons adjacent to carbonyl at around 5.5 and 2.2 δ respectively for fatty acid along with amide proton at around 6.0-6.4 with the methylene proton in the amino acid moiety at around 4.6 δ. IR spectral data showed carbonyl peaks corresponding to both amide 1650 cm 1 and carboxylic acid 1710 cm 1 functionalities. The spectral data for characteristic peaks was observed to be in compliance to earlier reported data for the fatty amino acid conjugates 11,18 .…”

“…These types of compounds have been reported to be biodegradable and have applications in food, pharmaceutical, medical and cosmetic fields 9 . Earlier reports on N-palmitoylated amino acids and N-stearyl amino acids showed that these types of compounds exhibited biological activities and could have applications as potential biostatic additives 10,11 .…”

A Novel Synthesis of N-Alkoxycarbonyl Amino Acids and Surfactant Properties of Their Sodium Salts

“…Sodium salts of N-acyl amino acids are well-known anionic surfactants with good biodegradability, skin compatibility and antibacterial activity [1][2][3][4][5][6][7][8][9] . Generally, they have been prepared from fatty acid chlorides and amino acids [10][11][12][13][14][15] , where acid halides are used to introduce the hydrophobic groups.…”