<i>In vitro</i> and <i>ex vivo</i> antitubercular activity of diarylheptanoids from the rhizomes of <i>Alpinia officinarum</i> Hance

<p>Phytochemical investigation of methanol extract of the rhizomes of <i>Alpinia officinarum</i> Hance afforded four known diarylheptanoids 1,7-diphenylhept-4-en-3-one (<b>1</b>), 5-hydroxy-1,7-diphenyl-3-heptanone (<b>2</b>), 5-hydroxy-7-(4″-hydroxy-3″-methoxyphenyl)-1-phenyl-3-heptanone (<b>3</b>), and 7-(4″-hydroxy-3″-methoxyphenyl)-1-phenyl heptan-3-one (<b>4</b>).The acetate derivative of (<b>4</b>), 7-(4″-actetate-3″-methoxy phenyl)-1-phenyl heptan-3-one (<b>5</b>), was prepared. These diarylheptanoids exhibited promising <i>in vitro</i> and <i>ex vivo</i> antitubercular activity for the first time against dormant <i>Mycobacterium tuberculosis</i> H37Ra with the IC₅₀ values between 0.34<b>–</b>47.69 and 0.13–22.91 μM, respectively. All compounds showed comparable activity against <i>Mycobacterium bovis</i> BCG (dormant phage) and did not show any activity against two gram + ve and two gram –ve bacterial strains. These compounds were also weakly cytotoxic up to 300 μM against three human cancer cell lines THP-1, Panc-1 and A549.</p