Antimicrobial Activities of Green and Red Brazilian Propolis

Green and red Brazilian propolis: antimicrobial potential and anti-virulence against ATCC and clinically isolated multidrug-resistant bacteria

Chem Biodivers. 2021 Jun 4

Brazilian green and red propolis stand out as commercial products for different medical applications. In this paper, we report the antimicrobial activities of the hydroalcoholic extracts of green (EGP) and red (ERP) propolis, as well as guttiferone E plus xanthochymol (8) and oblongifolin B (9) from red propolis, against multidrug-resistant bacteria (MDRB). 

We undertook the minimal inhibitory (MIC) and bactericidal (MBC) concentrations, inhibition of biofilm formation (MICB 50 ), catalase, coagulase, DNase, lipase, and hemolysin assays, along with molecular docking simulations. ERP was more effective by displaying MIC and MBC values < 100 μg.mL -1 . 

Compounds 8 and 9 displayed the lowest MIC values (0.98 to 31.25 µg.mL -1 ) against all tested Gram-positive MDRB. They also inhibited the biofilm formation of S. aureus (ATCC 43300 and clinical isolate) and S. epidermidis (ATCC 14990 and clinical isolate), with MICB 50 values between 1.56 and 6.25 µg.mL -1 . The molecular docking results indicated that 8 and 9 might interact with the catalase's amino acids. Compounds 8 and 9 have great antimicrobial potential.