Antibacterial, antibiofilm and antioxidant activity of secondary metabolites of antagonistic bacterial strain Bacillus endophyticus PK2 isolated from marine soil

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Research Paper 12/09/2022
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Antibacterial, antibiofilm and antioxidant activity of secondary metabolites of antagonistic bacterial strain Bacillus endophyticus PK2 isolated from marine soil

Tharani Jayakumar, Ishwarya Rajendran, Geetha Mani, Sangeetha Dhayalan
Int. J. Biosci.21( 3), 130-138, September 2022.
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A prime source of diverse antibacterial and anticancer drugs is the bacterial metabolites produced by marine organisms. In this research, we isolated the antagonistic marine bacterial strain Bacillus endophyticus PK2 from seashore soil samples and assessed its antibacterial and antioxidant properties of crude secondary metabolites of strain PK2. The potent antagonistic bacterial isolate PK2 was discovered using 16S rRNA sequencing analysis. The secondary metabolites from strain PK2 were extracted by centrifugation with ethanol, and the agar well diffusion method was used to evaluate them for antibacterial activity against respiratory tract bacterial pathogens. This study demonstrated that the secondary metabolites of PK2 effectively inhibited the growth of respiratory tract bacterial pathogens and effectively hindered their biofilm formation. Moreover, established effective concentration-dependent DPPH radical scavenging activity in in vitro conditions. The results of the growth optimization tests indicated that the strain PK2 showed effective growth at temperatures between 30 and 40 °C and a pH range of 7-8. Therefore, upon additional clinical testing, the secondary metabolites of strain B. endophyticus PK2 may be exploited to create potent antibiotic and anticancer drugs.


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