Antagonistic Activities of Cell Free Ethyl Acetate Extracts of Marine Sponge Derived Aspergillus Melleus Mp3

Objective: This piece of work aims to determine the antagonistic potential of Aspergillus melleus MP3 fungi from marine sponge. Methods: Marine sponge extract was used to isolate fungi on selective medium and molecular identification was performed using ITS sequencing. Fungal mycelium was extracted with solvents of varying polarity and their antibacterial activity was checked against various human pathogenic bacteria using the agar disk diffusion method. Ethyl acetate extracts showed promising results. The bioactive metabolites were purified on TLC and analysed using GC-MS. The mechanism of action of bioactive metabolite was found by estimating the amount of protein present in four potent human pathogens. The proteins were visualised by SDS-PAGE to identify the molecular weight. The cytotoxic ability of the fungi was assessed by MTT assay on HEP2 carcinoma cell line. Structure of the metabolites were analysed using XRD and 1H NMR and 13C NMR. Result: Molecular data revealed the identity of the fungi as Aspergillus melleus MP3 and novelty of the sequence lead to its deposition in GENBANK with Accession number HQ 449678.3. Varying concentrations of the fungal filtrate was analysed to identify IC50 . The IC50 0f the Aspergillus melleus MP3 extract on HEP2 cell line was found to be 6.25 μg. The appearance of a multiple band on SDS-PAGE further suggests the proteins to be multimeric. Conclusion: The present study of screening bioactive secondary metabolites revealed that Aspergillus terreus as a source for the production of three effective metabolites.