OSMAC Approach and Cocultivation for the Induction of Secondary Metabolism of the Fungus <i>Pleotrichocladium opacum</i>
Víctor Rodríguez, Mònica Martínez, Cristina Cuadrado, Antonio Hernández Daranas, Antonio Fernández Medarde, José María Sánchez-López
Abstract
High Resolution Image Download MS PowerPoint Slide The application of an OSMAC (One Strain–Many Compounds) approach on the fungus Pleotrichocladium opacum, isolated from a soil sample collected on the coast of Asturias (Spain), using different culture media, chemical elicitors, and cocultivation techniques resulted in the isolation and identification of nine new compounds ( 8, 9, 12, 15 – 18, 20, 21 ), along with 15 known ones ( 1 – 7, 10, 11, 14, 19, 22 – 25 ). Compounds 1 – 9 were detected in fungal extracts from JSA liquid fermentation, compounds 10 – 12 were isolated from a solid rice medium, whereas compounds 14 and 15 were isolated from a solid wheat medium. Addition of 5-azacytidine to the solid rice medium caused the accumulation of compounds 16 – 18, whereas adding N -acetyl- d -glucosamine triggered the production of two additional metabolites, 19 and 20 . Finally, cocultivation of the fungus Pleotrichocladium opacum with Echinocatena sp. in a solid PDA medium led to the production of five additional natural products, 21 – 25 . The structures of the new compounds were elucidated by HRESIMS and 1D and 2D NMR as well as by comparison with literature data. DP4+ and mix- J -DP4 computational methods were applied to determine the relative configurations of the novel compounds, and in some cases, the absolute configurations were assigned by a comparison of the optical rotations with those of related natural products.