RESUMO
The propolis produced by stingless bees of the tribe Meliponini is a viscous product that contains the resin collected from buds, leaves and plant exudates, mixed with salivary secretions, wax and soil. The species Scaptotrigona aff. postica (Latreille, 1807), (Hymenoptera, Apidae, Meliponinae) popularly known as “tubi” in Maranhão State, Brazil, does not mix soil to produce its propolis. The propolis from S. postica harvested in Barra do Corda, Maranhão State, is popularly used in the treatment of wounds and respiratory illnesses. The hydroalcoholic extract of this propolis, rich in flavone-6,8-di-C-glycosides (vicenin-2 and schaftoside), pyrrolizidine alkaloids derived from retronecine, catechin and caffeoylquinic acid derivatives exhibited antiviral activity against the herpes simplex and rubella viruses. The aim of this study was to increase knowledge about the chemical composition of the S. postica propolis by analyzing non-polar extracts obtained using hexane and chloroform as the solvents, by GC-EI-MS. A total of 15 constituents were identified comparing their respective mass spectral data with those available in the NIST data bases and those reported in the literature. The main constituents detected were the phenolic lipids, known as cardanols, 3-(4,7-heptadecadienyl) phenol (5), 3-(10-heptadecenyl) phenol (7), 3-heptadecylphenol (9) and 3-pentadecyl phenol or hydrocardanol (13), which predominated in the hexane extract, while the predominant constituents in the chloroform extract were 3-pentadecyl phenol or hydrocardanol (13) and 3-(8-pentadecenyl) phenol (12). The antioxidant, antitumoral, antifeedant, cytotoxic, anticarcinogenic, antiproliferative, antimicrobial, antileishmanial and larvicidal activities of the cardanols have been demonstrated in many studies.
RESUMO
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.