| Abstrakt: |
Endophytic Bacillus spp. associated with Archidendron pauciflorum could be the potential source of active compounds attributed to the pharmacological property. The present study aimed to determine the antioxidant, antibacterial, antibiofilm activities, and phytochemical profiles of the crude extracts derived from four endophytic Bacillus spp. isolated from A. pauciflorum. Among all extracts tested, extract from Bacillus pseudomycoides strain DJ8 displayed the strongest antioxidant activity against DPPH and ABTS with IC50 values of 24.87±1.81 and 9.18±0.10 µg/mL, respectively. As evaluated by the dual culture-agar diffusion and disc diffusion methods, three out of four Bacillus spp. extracts also exhibited broad spectra of antibacterial activity against four ATCC strains. Among other extracts, B. pseudomycoides strain DJ8 extract became the most active extract inhibiting Staphylococcus aureus strain ATCC 6538, indicated by the lowest MIC (31.25 µg/mL) and MBC (125 µg/mL), which is considered a highly active antibacterial agent. Three extracts attributed to broad spectra antibacterial activity were also capable to inhibit biofilm formation of four ATCC strains, up to 62.59% in 2 MIC of the extract concentration. Phytochemicals (flavonoid, alkaloid, and terpenoid) were present in four endophytic Bacillus extracts. Among other extracts, an extract derived from B. pseudomycoides strain DJ8 contains the highest flavonoid content (40.10±1.18 mg QE/g extract) and phenol (58.50±4.56 mg GAE/g extract). In conclusion, these four endophytic Bacillus spp. could be the source of pharmaceutically valuable compounds attributed to antioxidant, antibacterial, and antibiofilm properties. [ABSTRACT FROM AUTHOR] |
