Harungana madagascariensis as a source of antibacterial agents

The present chapter provides knowledge on the ethnopharmacological uses, phytochemistry, and antibacterial potential of Harungana madagascariensis (Hypericaceae). The plant is mainly distributed in tropical Africa and Madagascar, where it has been used in folk medicine to cure several diseases including dysentery, diarrhea, anemia, typhoid, heart ailments, angina, syphilis, gonorrhea, asthma, tuberculosis, malaria, viral, and parasitic skin diseases, liver, and renal diseases. Its antibacterial potential has been reported against drug-sensitive and multidrug-resistant (MDR) phenotypes. Botanicals, as well as phytochemicals from H. madagascariensis displayed strong inhibitory activities against a panel of sensitive and MDR bacteria, including Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Salmonella typhi, Klebsiella pneumoniae, Acinetobacter sp., and Pseudomonas aeruginosa. The major antibacterial constituents of H. madagascariensis include anthranoids, namely ferruginin A, euxanthone, harunmadagascarin D, kenganthranol C, and astilbin. Conclusively, H. madagascariensis is a good source of antimicrobial drugs to combat both sensitive and MDR bacteria and deserves further investigation to develop herbal medicine and pharmaceuticals to overcome bacterial drug resistance.