Evaluation of the in vitro antimicrobial activity of alcoholic solution and aqueous extract of bee propolis against enterococcus faecalis

AIM: The purpose of this study was to analyze the in vitro antimicrobial activity of aqueous and alcoholic extracts of propolis at 1% and 3% concentrations against Enterococcus faecalis (ATCC® 19433). MATERIAL AND METHODS: Initially, the microbial suspension was seeded in a Brain Heart Infusion Agar (BHIA) culture medium, distributed in 20 Petri dishes. Then, 4 soaked filter paper discs were placed on the surface of the inoculated medium of each plate for 1 minute in 1 mL of the following substances: C+ (positive control, n=20): 2% chlorhexidine gel; C- (negative control, n=20): saline solution; S1 (n=10): 1% bee propolis alcoholic solution; S2 (n=10): 3% bee propolis alcoholic solution; E1 (n=10): 1% aqueous propolis extract; E2 (n=10): 3% aqueous propolis extract. One filter paper disc of each (C+, C-, S1 and S2) was placed in a set of 10 Petri dishes, whereas one filter paper disc of each (C+, C-, E1 and E2) was placed in the other set of 10 Petri dishes. RESULTS: The results obtained after incubation at 37°C for 24 hours under microaerobic conditions revealed that S2 showed higher mean levels of microbial growth inhibition as compared to E1, E2 and S1. There were no significantly statically differences between the groups, except for the S2 group and C- group. Mean levels in all other groups were lower than in the C+ group. CONCLUSION: The study concluded that 1% and 3% bee propolis alcoholic solution had lower antibacterial activity against Enterococcus faecalis as compared to 2% chlorhexidine gel.

Antiviral activity of Agaricus blazei Murrill ss. Heinem extract against human and bovine herpesviruses in cell culture

The aqueous extract of Agaricus blazei Murill ss. Heinem, a basidiomycete native from Brazil, frequently used by popular medicine, mainly in the form of tea, was assessed to its antiviral action against herpes simplex type 1 (HSV-1) and bovine herpes type 1 (BoHV-1) in HEp-2 cell culture. Viral replication inhibition was evaluated by plaque assay and immunofluorescence test. The extract demonstrated virucide action for both viruses, being more effective against HSV-1, inhibiting its infectivity in 78.4 and 73.9 percent at the concentrations of 50 and 100 æg/mL, respectively moreover, reduction in 47 percent the number of fluorescent cells was observed for both concentrations. The extract also showed discrete therapeutic activity. These results suggest that A. blazei extract acts mainly in the viral particle, however, the effect during virus replication can not be ruled out.

O extrato aquoso de Agaricus blazei Murill ss. Heinem, um basidiomiceto nativo do Brasil, usado na medicina popular, na forma de chá, foi avaliado quanto suas propriedades antivirais contra herpes simplex tipo 1 (HSV-1) e herpes bovino tipo 1 (BoHV-1) em cultura de células HEp-2. A inibição da replicação viral foi monitorada pelos ensaio de placa e reação de imunofluorescência. O extrato apresentou atividade virucida mais efetiva do que terapêutica para ambos os vírus, sendo mais efetivo portanto para HSV-1, inibindo em mais de 70 por cento o número de plaques e em cerca de 47 por cento o número de células apresentando fluorescência específica, nas concentrações de 50 e 100 æg/mL, nas duas técnicas utilizadas. Os resultados obtidos sugerem que o extrato aquoso de A. blazei deve agir principalmente sobre a partícula viral, embora a inibição durante o ciclo replicativo do vírus não deva ser excluída.