Antioxidant study indicative of antibacterial and antimutagenic activities of an ellagitannin-rich aqueous extract from the leaves of Miconia latecrenata

• Published in: Journal of ethnopharmacology Vol. 236; pp. 114 - 123
• Main Authors: Gontijo, Douglas Costa, Gontijo, Pablo Costa, Brandão, Geraldo Célio, Diaz, Marisa Alves Nogueira, de Oliveira, Alaíde Braga, Fietto, Luciano Gomes, Leite, João Paulo Viana
• Format: Journal Article
• Language: English
• Published: Ireland Elsevier B.V 23-05-2019
• Subjects: Bio-statistical analysis; DNA protection; LC-MS; Melastomataceae; Phenolic compounds; ROS/RNS; ROS/RNS; Melastomataceae; LC-MS; DNA protection; Phenolic compounds; Bio-statistical analysis
• ISSN: 0378-8741; 1872-7573
• DOI: 10.1016/j.jep.2019.03.007

Ethnopharmacological relevance; Several plant species of Miconia genus are commonly used in Brazilian folk medicine as anti-inflammatory agents and for the treatment of infectious diseases. Infusions and extracts of Miconia species are also reported as analgesic, antimicrobial, antimalarial, antioxidant, anti-inflammatory, antinociceptive, antimutagenic, and antitumoral.
Aim of the study; To determine the phytochemical composition of an aqueous extract of Miconia latecrenata leaves and to evaluate its antioxidant, antibacterial, antimutagenic and antigenotoxic activities.
Materials and Methods; The following methods were used for the different effects: I) antioxidant - β-carotene/linoleic acid, lipid peroxidation, and DPPH• radical scavenging; II) antibacterial - agar well diffusion and MIC methods); III) antimutagenic assays - Ames Test; and IV) antigenotoxic - Plasmid cleavage test. The phytochemical analysis and phenolic quantification were carried out by UPLC-DAD-ESI-MS/MS and colorimetry, respectively. In addition, statistical correlation analysis was performed aiming to evaluate the Pearson correlation between phenolic compounds and biological assays.
Results; A high content of tannins was observed and the ellagitannin isomers of 1,2,3,5-tris-galloyl-4,6-HHDP-glucose were identified as the main constituents of the leaves aqueous extract. High antioxidant effect, in different tests, high antibacterial activity to gram-positive and negative strains, as well as high antimutagenic activity were observed. Statistical analysis showed a high Pearson correlation for the tannin content in relation to the results of the antioxidant and antibacterial tests. In general, the antioxidant action of the aqueous extract showed low correlation with the antimutagenic activity.
Conclusions; The present results confirmed the expectations regarding the pharmacological profile of M. latecrenata supporting its therapeutic potential in relation to ROS/RNS related disorders. Furthermore, the phenolic compounds of M. latecrenata can act, in turn, minimizing or inhibiting the biological macromolecules damage, especially DNA.
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•Natural phenolic compounds can reducing damage in biological macromolecules.•Aqueous extract of Miconia latecrenata leaves (EML) show high antioxidant action.•EML show high antibacterial action for gram positive and negative strains.•EML show high antimutagenic activity in the different strains in Ames test.•EML show correlation of phenolic compounds with antioxidant and antibacterial tests.