Secondary metabolism variation in endophytic marine fungi by chemical epigenetic elicitation approaches

Chemical epigenetic elicitation is a new approach to access unknown and/or remarkable natural products that have been used with success in last years. Three strains of marine endophytic fungi, isolated from red algae, were submitted to chemical elicitation and they showed changes in their secondary metabolism. Some major substances of Penicillium decaturense were inhibited when sodium butyrate (100µM) was used. Moreover, new peaks were observed by means of HPLC analysis, indicating the presence of new metabolites biosynthesized through elicitation experiments. The Xylariaceae sp. strain had its metabolism increased speed using procaine as elicitor while valproic acid (both 100µM) was responsible to promote the production of some metabolites in 7 days experiment, metabolites which usually appeared in 14 days without any elicitated conditions. In Phomopsis longicolla strain, the production of bioactive dicerandrol C (earlier isolated just in solid rice medium) was stimulated in liquid medium (PDB) in 7 days by sodium butyrate (100µM) modulation. In the same experiment, after 21 days growth, new chromatogram peaks pointed out the new halogenated metabolites (isotopic abundance observed by mass spectrometry) production. More detailed chemical investigations are been carried out to determine the new secondary metabolites produced. Therefore, we can corroborate that chemical epigenetic elicitation is an important approach to validate the chemical profile variation in fungi, besides to promote new metabolites biosyntheses.