Identification of Bioactive Coumarin(s) from Three Endophytic Fungal Species of Calophyllum tomentosum

Background: Many biologically important bioactive compounds have been identified in Calophyllum tomentosum extract. Hence, we aimed to identify different endophytic fungal species from different parts of the plants and their bioactive compounds. Objective: The study includes identification and characterization of bioactive compounds in the extracts of endophytic fungal species of Calophyllum tomentosum. Methods: Different parts were used to assess the different endophytic fungi. Two different solvents were used: extracts and qualitative solvents. TLC and GC-MS were employed to identify the bioactive compounds. The bioactive compounds producing endophytes were identified by using18S rRNA. Results: In total, 13 different fungal species were identified from different parts of the Calophyllum tomentosum. The C. tomentosum leaf part showed seven different fungal endophytes from the barks (four) and stems (two). The methanol extract of Fusarium species (stem), Cladosporium species (bark) and hexane extract of Alternaria species (bark) showed a higher amount of coumarins in qualitative methods and TLC. Based on the above results, for further GC-MS and molecular identification studies, we selected three endophytes. In the GC-MS analysis, the methanol extract of Fusarium species (stem) showed psoralen, and furocoumarin (imperatonin or ammidin); Cladosporium species (bark) showed coumarin (2H-1-benzopyran-2-one), coumaric acid (3-benzofurancarboxylic acid), hynecromone (coumarin 4), 4-hydroxy-9-(3-methyl-2-butyl)furo(3,2-g)chloronen-7- one; and hexane extract of Alternaria species (bark) showed coumaric acid (3-benzofurancarboxylic acid). The three fungal endophytes were identified as Fusarium equiseti, Cladosporium uredinicola and Alternaria alternata from 18S rRNA analysis. Conclusion: Based on the above results, the three endophytic fungal species confirm the presence of coumarins and therefore, can be used for the production of coumarins instead of the plant.