Production of a phenolic-rich extract of aroeira honey and characterization of its antimicrobial, antitumoral and antioxidant activities

Objective: a phenolic-rich extract of Astronium urundeuva honey (PhEAH) wasproduced and its pharmacological proprieties were determined. Method: PhEAHwas prepared using a solid-phase extraction column. Next, antibacterial and antifungalactivities were evaluated by broth microdilution method and the antioxidanteffect was investigated using 2,2-Diphenyl-1-picrylhydrazyl (DPPH) assay. Urethralcatheter sensitized with PhEAH were produced and its anti-adhesive and anti-biofilmeffect determined. Finally, antitumoral and antiviral activities were studded using3-(4.5-dimethylthiazol-2-yl)-2.5-diphenyltetrazolium bromide (MTT) test. Results:PhEAH showed an elevated total phenol concentration (PhEAH: 18.7±0.4 mg GA/g vs. fresh honey: 0.99±0.005 mg GA/g). Although PhEAH did not show significantantifungal and antiviral effects, it was moderately active against Gram-negative bacilli(Klebsiella aerogenes, K. pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa andEnterobacter cloacae) and showed increased antibacterial activity against salmonellosispathogens (Salmonella Typhimurium and Salmonella Enteritidis). PhEAH-impregnatedurethral catheters inhibited the growth of various pathogenic bacteria andimpaired the ability of P. aeruginosa to colonize and adhere to it. In addition to its antimicrobialactivity, PhEAH presented antioxidant properties and reduced the viabilityof human glioblastoma cells. Conclusion: in conclusion, our study shows that PhEAHcontains large amounts of phenolic compounds, which are associated with its antibacterial,anti-adhesive, antioxidant, and antitumor effects.