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Marine sponge alkaloid aaptamine is a promising anti-bacterial and anti-cancer drug against ESBL producing Gram negative bacteria and HepG 2 human liver carcinoma cell line. The antibacterial activity of aaptamine against selected ESBL producing Gram negative bacteria was inhibited at the concentration of 55 µg/mL. At the minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) of 50 µg/mL, the aaptamine was significantly effective against all the ESBL positive uropathogens. Importantly, the inhibition was much high compared to other marine compounds through intracellular damage and morphological modification by confocal laser scanning electron microscope (CLSM) and scanning electron microscope (SEM). Further, the cytotoxic efficacy of aaptamine against HepG 2 cells was showed at 75 µg/mL very effectively and this concentration was indicated as IC50 dose. The morphological and intracellular nuclear damage of aaptamine treated HepG 2 cell was detected by florescence microscope using acridine orange/ethidium bromide (AO/EB) combination and Hoechst 33342 staining assays. The nuclear fragmentation of aaptamine treated HepG 2 cells were confirmed by expression of Caspase-9, Caspase-8, Caspase-3 cleavage, which provide the suggestion for the induction of intrinsic and extrinsic apoptosis pathways. In addition, the western blot analysis of appatamine treated HepG 2 cells also confirmed that the expression genes were damaged and the aaptamine showed dose and time dependent relationship. Hence, our findings suggest, the marine natural compounds aaptamine might be a potential alternative agents for ESBL producing uropathogens and human liver cancer therapy.

The aim of this study is to identify potential antibacterial compounds of endophytic actinomycetes (EA) from marine algae Caulerpa racemosa for inhibit the multi drug resistant (MDR) Gram negative bacteria (GNB) including Eschericia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa), Proteus mirabilis (P. mirabilis), Klebsiella pnumonia (K. pnumoniae) and Enterobacter sp., which were confirmed by UTI panel antibiotic discs. Among the 100 EA, five strains were showed better antogonistic activity against all the selected uropathogens. In the ethyl acetate extract, the NMS 5 strains of EA showed excellent anti-bacterial activity against all the MDR uropathogen. Further, the NMS 5 extract was partially purified from thin layar chramatogaraphy (TLC) and spot 3 of TLC crude compound showed 14, 12 mm zone of inhibition against both the uropathogens. In addition, the minimum inhibition concentration (MIC) of crude exhibited the inhibition percentage was 87 and 84 at 120 µg/mL concentration. The MIC was confirmed by minimum bactericidal concentration (MBC) and it was indicated same as MIC. The treated NMS 5 crude compound of P. aeruginosa and K. pneumonia cells were showed more dead cells, intracellular damage and morphological damage with disaggregated cells by confocal laser scanning electron microscope (CLSM) and scanning electron microscope (SEM). Hence, the present study was revealed that the algae derived EA have the potential anti-bacterial metabolites for inhibition of MDR bacteria and it can be applied for various other infections after further purification.