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Antimicrobial Peptides Produced by Selective Pressure Incorporation of Non-canonical Amino Acids
Published on: May 4, 2018
Isolation and antioxidative activity of amino acid derivatives produced by Leuconostoc mesenteroides
Yu Geon Lee1, Jeong-Yong Cho1, Jae-Hak Moon1
1Department of Food Science and Technology and Functional Food Research Center, Chonnam National University, Gwangju, 61186 Korea.
Abstract:
One new phenyl lactic acid derivative, N-(5-amino-2-hydroxy-1-oxopentyl)-tyrosine (2), and three known metabolites [(S)-8-hydroxy-4-hydroxy-phenylpropanoic acid (1), (S)-8-hydroxy-phenylpropanoic acid (3), and indole-(S)-3-lactic acid (4)] were isolated from the culture medium of Leuconostoc mesenteroides guided with DPPH radical-scavenging assay. The chemical structures of the isolated compounds were determined by NMR and electrospray ionization mass spectroscopy. The isolated four compounds were assumed to be metabolites formed by the transformation of amino acids. The DPPH radical-scavenging activities of 1 and 2 were significantly higher than those of 3 and 4. This result may provide meaningful information of antioxidative metabolites from lactic acid bacteria.
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