Klebsiella pneumoniae that is resistant to carbapenem antibiotic has emerged as the fourth common cause of pneumonia in intensive care units. There is a dire need for unique antibiotics since the treatment options for Carbapenem resistant - Klebsiella pneumoniae (CR-KP) are very limited. Ninety eight marine actinobacterial strains were screened for antibacterial efficacy against carbapenem-resistant K. pneumoniae ATCC BAA-1705, in which strain SACC-E6 showed a maximum of 20 mm zone of inhibition. Active molecules from strain SACC E6 was extracted with organic solvents, such as methanol, chloroform, ethyl acetate, and n-hexane, by solid liquid extraction method. Antibacterial activity of all the extracts was tested by the paper disk diffusion method at a concentration of 100 μg/disk. Methanolic extract of the strain SACC-E6 showed a maximum of 24 mm inhibition. Two active molecules from the methanol extract of strain SACC-E6 were detected by thin layer chromatography-based bioautogram. The taxonomical investigation revealed that strain SACC E6 was Streptomyces maritimus. According to the literature, only 1.5% of actinobacteria from any ecosystem was found be active against Gram-negative bacterial pathogens. Interestingly, around 31.63% of marine actinobacterial strains showed activity against CR-KP. Also, the results showed that marine S. maritimus SACC-E6 is a reliable resource for the anti-infective molecules effective against K. pneumoniae that is resistant to carbapenem antibiotic.
Key words: Cr-Kp, Streptomyces maritimus, anti-bacterial, TLC, bioautogram
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