• Botryane, noreudesmane and abietane terpenoids from the ascomycete Hypoxylon rickii.

      Kuhnert, Eric; Surup, Frank; Wiebach, Vincent; Bernecker, Steffen; Stadler, Marc; Helmholtz Centre for infection research, Inhoffenstr. 7, D-38124 Braunschweig, Germany. (2015-09)
      In the course of our screening for new bioactive natural products, a culture of Hypoxylon rickii, a xylariaceous ascomycete collected from the Caribbean island Martinique, was identified as extraordinary prolific producer of secondary metabolites. Ten metabolites of terpenoid origin were isolated from submerged cultures of this species by preparative HPLC. Their structures were elucidated using spectral techniques including 2D NMR and HRESIMS. Three of the compounds were elucidated as new botryanes (1-3) along with three known ones, i.e. (3aS)-3a,5,5,8-tetramethyl-3,3a,4,5-tetrahydro-1H-cyclopenta[de]isochromen-1-one (4), (3aS,8R)-3a,5,5,8-tetramethyl-3,3a,4,5,7,8-hexahydro-1H-cyclopenta[de]isochromen-1-one (5) and botryenanol (6). Further three new sesquiterpenoids featured a 14-noreudesmane-type skeleton and were named hypoxylan A-C (7-9); the diterpenoid rickitin A (10) contains an abietane-type backbone. Compounds 1, 2, 3, 7, and 10 showed cytotoxic effects against murine cells.
    • Edonamides, the first secondary metabolites from the recently described myxobacterium Aggregicoccus edonensis

      Karwehl, Sabrina; Mohr, Kathrin I.; Jansen, Rolf; Sood, Sakshi; Bernecker, Steffen; Stadler, Marc; Helmholtz Centre for Infection Research,Inhoffenstr. 7; 38124 Braunschweig, Germany. (2015-11)
    • Large Scale Production and Downstream Processing of Labyrinthopeptins from the Actinobacterium .

      Rupcic, Zeljka; Hüttel, Stephan; Bernecker, Steffen; Kanaki, Sae; Stadler, Marc; Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7, 38124 Braunschweig, Germany. (2018-06-05)
      A method was established for the production of 1.2-fold and 4.2-fold increased amounts of the antiviral and central nervous system-active lantipeptides, labyrinthopeptins A1 and A2, respectively, isolated from the actinobacterium