Activity of ethyl acetate extracts of marine-derived fungi against active and hypoxia-induced dormant Mycobacterium

Context: : Tuberculosis requires long therapy (6-9 months) to eradicate the tubercles from the body completely. This is partly caused by the ability Mycobacterium tuberculosis to induce a dormant state that exhibits a resistant phenotype against recent antituberculosis. Hence, alternative compounds are required, especially the ones that are active against both active and dormant Mycobacterium. . Marine-derived fungi are known to be a prolific source bioactive secondary metabolites. Aims: : To evaluate the isolated fungi from marine resources and investigate their antimycobacterial activity in aerobic and hypoxic conditions. Methods: : The research included marine sources sampling, isolation of fungi, fermentation, and screening for antimycobacterial activity against Mycobacterium smegmatis in aerobic conditions. The chosen fungi isolates were continued with molecular identification and further investigation against hypoxic-induced dormant M. smegmatis. . The antimycobacterial activity is determined using the microdilution method and visualization by 3-(4,5dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Results: : As many as 49 fungi were successfully isolated from 40 marine samples, with two fungi exhibiting promising results, namely FSPL 3 (identified Aspergillus ostianus) ) and FSB 34 (identified as Aspergillus flavus). ). The highest activity was shown by A. ostianus media ethyl acetate extracts, with the minimum inhibitory concentration (MIC) of 6.25 mu g/mL against active and dormant M. smegmatis, , followed by A. ostianus biomass and A. flavus media ethyl acetate extracts with the MIC of 25 mu g/mL against both active and dormant M. smegmatis. . Conclusions: : The ethyl acetate extracts of A. ostianus media showed prospective activity to investigate further the active compounds as anti-dormant mycobacterial.