Asterisulphoxide and asterisulphone: two new antibacterial and antifungal metabolites from the Tunisian <i>Asteriscus maritimus</i> (L.) Less

<div><p>Two new sulphur-containing metabolites, asterisulphoxide <b>1</b> and asterisulphone <b>2</b>, together with six known compounds, coniferaldehyde <b>4</b>, 4-hydroxy-2-methoxybenzaldehyde <b>3</b>, methylcaffeate <b>5</b>, isobutyrate 10-isobutyryloxy-8,9-epoxythymyle <b>6</b>, 8,9-dihydroxy-10-isobutyryloxythymol <b>7</b> and 8-hydroxy-9,14-diisobutyryloxythymol <b>8</b>, were isolated from <i>Asteriscus maritimus</i> roots. Their structures were elucidated on the basis of spectroscopic evidence and comparison with authentic samples. Compounds <b>1</b>–<b>8</b> were assessed for their <i>in vitro</i> antibacterial activity against <i>Pseudomonas aureofasciens</i>, <i>Burkholderia glathei</i>, <i>Bacillus pumilus</i> and their antifungal effects against <i>Aspergillus flavus</i>, <i>Aspergillus</i><i> niger</i>, <i>Penicillium digitatum</i>, <i>Botrytis cinerea</i> and <i>Fusarium oxysporum</i> f. sp. <i>lycopersici,</i> using the disc diffusion method (20 μL/disc). A remarkable inhibition zone 10–15 mm of the growth of the bacterial and fungal agents was observed. The obtained results suggest that the isolated compounds could be promising abiotic antimicrobial agents.</p></div>