Antibacterial activity of Cu(II) and Co(II) porphyrins: role of ligand modification

• Main Authors: Belete B. Beyene, Getaneh A. Wassie
• Format: Article
• Language: English
• Published: BMC 2020-08-01
• Series: BMC Chemistry
• Subjects: Cobalt porphyrin; Inhibition; Copper porphyrin; Antibacterial activity; Lipophilicity
• Online Access: http://link.springer.com/article/10.1186/s13065-020-00701-6

Abstract In this study, we report antibacterial activity of metalloporphyrins; 5, 10, 15, 20-tetrakis (para-X phenyl)porphyrinato M (II) [where X = H, NH2 and COOMe for M = Cu and X = COOH  and OMe for M = Co]. The activity study of the as-synthesized metalloporphyrins toward two Gram-positive (S. aureus and S. pyogenes) and two Gram-negative (E. coli and K. pneumoniae) bacteria showed a promising inhibitory activity. Among the complexes under study, the highest antibacterial activity is observed for 5, 10, 15, 20-tetrakis (p-carboxyphenyl)porphyrinato cobalt (II), with inhibition zone of 16.5 mm against Staphylococcus aureus (S. aureus). This activity could be attributed to the high binding ability of COOH group to cellular components, membranes, proteins, and DNA as well as the lipophilicity of the complex. Moreover, consistent with literature report, the study revealed that metalloporphyrins with electron withdrawing group at para-positions have better antibacterial activity than metalloporphyrin which possess electron donating group at para position.