Isolation and Purification of Bioactive Compounds from Endophytic Bacillus sp. RD26 Associated with Phyllanthus Amarus

This study investigated the bioactive properties of Bacillus amyloliquefaciens RD26, an endophyte isolated from Phyllanthus amarus. The methanol extract of Bacillus sp. RD26 showed significant antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA), with an inhibition zone of 25 ± 0.57 mm. The antibacterial compound, BR04, was isolated and identified as pyrimidine-2,4-dione (uracil), showing potent antimicrobial effects with minimum inhibitory concentrations (MICs) of 64 µg/mL against MRSA, 128 µg/mL against Bacillus cereus, and 512 µg/mL against Escherichia coli. In addition, BR04 showed antioxidant activity and scavenged up to 50% of DPPH free radicals at a concentration of 1800 μg/mL. These findings highlight the potential of BR04 as a bioactive compound for pharmaceutical and agricultural applications, particularly in combating infectious pathogens and providing a natural alternative to synthetic antioxidants.