Tuberculosis (TB), an infectious bacterial disease caused by Mycobacterium tuberculosis with extensive resistance against antibiotic . Using a stringent cell-based assay with Acanthamoeba castellani as host for the pathogen M. marinum , the extracts from an ethnopharmacologic survey were screened for antimycobacterial activity [Kicka &al PlosOne 2014] . Among the plants evaluated, the extract of Combretum aculeatum exhibited a relevant antimycobacterial activity [Diop E.A &al JEP 2017] . In order to identify the active principles, a bioassay-guided fractionation was undertaken using flash chromatography. The higher activities were linked to the fractions containing the anomers (α- and β) of the ellagitannin punicalagin (PNG) that were further purified. PNG have been reported to be responsible for various pharmacological activities, such as inhibition of carcinogenesis, host-mediated antitumor activities and antiviral activities. These PNG are however known to be extensively metabolized when ingested orally. E llagitannins hydrolysis yield ellagic acid, which is subsequently transformed by the human colon microflora into urolithins derivatives [Cerda,B &al J. Agr. Food. Chem 2003] .
To better document the possible anti-TB efficacy of C. aculeatum, the metabolites urolithin A, B and D were thus acquired and their antimycobacterial activity was assessed. Ellagic acid inhibited the growth of M. marinum in broth with an IC50 of 48.3 µg/ml. Urolithin D exhibited relevant anti-infective activities , with IC50 of 89.91 µg/ml. A quantification of PNG in the C. aculeatum preparation showed that its consumption at the usual doses may yield plasmatic levels of active metabolites in a concentration range similar to the IC50 determined in the in vitro assays. These results provide a rational for the use of this decoction for TB management.