Boletus griseipurpureus Corner: Antibacterial, Antioxidant Properties and Phytochemical Compositions

This study aims to investigate the properties of B. griseipurpureus Corner concerning its efficacy against various bacterial strains and its antioxidant capacity, along with its phytochemical composition. The antibacterial activity was evaluated using the agar well diffusion method, revealing pronounced efficacy against gram-negative bacteria, particularly noteworthy against E. coli ESBL182, known for its antibiotic resistance. The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of B. griseipurpureus Corner extract against E. coli ESBL182 were determined to be 75 and 300 mg/ml, respectively. The extract exhibited bacteriostatic activity by inhibiting cell growth, leading to a reduction in optical density at 600 nm. Additionally, examination of the supernatant from untreated and treated E. coli ESBL182 cells with B. griseipurpureus Corner extract indicated absorbance values of 0.088 and 0.248 at 260 nm, and 0.045 and 0.286 at 280 nm, respectively. Further investigation utilizing a scanning electron microscope revealed alterations in the morphology of treated cells, which displayed elongation and fragmentation, in contrast to untreated cells. The DPPH assay indicated that the IC50 of B. griseipurpureus Corner extract was 31.22 mg/ml. The IC50 value obtained from the ABTS assay was 47.31 mg/ml. Additionally, the FRAP assay revealed that the concentration of ascorbic acid equivalent in B. griseipurpureus Corner extract was 1.06 mg/g crude extract. Phytochemical analysis, conducted using a spectrophotometer at wavelengths of 750 nm and 510 nm, respectively, indicated phenolic and flavonoid contents of 0.22 mg gallic acid/g fresh weight and 3.23 mg quercetin/g fresh weight in the extract.