Geopropolis from Melipona scutellaris: antimicrobial and antiproliferative activities and its action on Streptococcus mutans biofilm in vitro

Author(s)

Marcos Guilherme da Cunha

• Document type: Master's Dissertation
• Press: Piracicaba, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Faculdade de Odontologia de Piracicaba
• Defense date: 2012-02-28

Examining board members

Pedro Luiz Rosalen; Marcelo Henrique dos Santos; Gilson Cesar Nobre Franco

• Advisor: Pedro Luiz Rosalen

Abstract

The present study concerning Melipona scutellaris geopropolis aimed to evaluate their antimicrobial activity against Streptococcus mutans and other pathogens of clinical importance, the antiproliferative activity on normal and tumor cell lines and to chemically characterize the ethanol extract and its bioactive chemical fraction. Further, also it analyzed the ability of this bioactive fraction acting on in vitro S. mutans biofilm. Initially it was obtained the ethanolic extract of geopropolis (EEGP), which was split, resulting in the hexane (HF), chloroform (CF) and ethyl acetate (FAC) fractions. The EEGP and fractions were tested to determine the minimum inhibitory (MIC) and minimum bactericidal concentrations (MBC) against S. mutans UA159 and five bacterial strains of clinical interest. After checked for antimicrobial activity, the EEGP and bioactive fraction were evaluated for their cytotoxicity through antiproliferative activity against normal and also tumor cells lines. The chemical characterization was performed by reverse phase high performance liquid chromatography (RP-HPLC) and gas chromatography with mass spectrometry (GC-MS). The action of selected bioactive fraction on S. mutans biofilms was evaluated by inhibition of biofilm formation, time kill, drop in pH assays, and scanning electron microscopy (SEM). The EEGP and HF were able to inhibit the growth of S. mutans and most bacterial strains, and HF presented the lowest MIC among the tested fractions. Concerning the antiproliferative activity, both EEGP and HF selectively inhibited the growth of tumor lines, but the HF at lower concentrations. Chemical analysis of EEGP and fraction indicated the presence of bioactive compounds of low polarity and the absence of flavonoids and cinnamic acid derivatives. The HF effectively reduced the biofilm biomass at both concentrations studied (250 and 400 mg / ml) compared with control (p<0.05), but did not affect bacterial viability (time kill), nor acid production by bacteria (p>0.05). The SEM analysis showed a change in the biofilm matrix treated with FH verified by the apparent loss of surface homogeneity. These data suggest that geopropolis is a promising source of active compounds against some bacteria, with more cytotoxicity to tumor cells than normal and also able to act on S. mutans biofilms, which may be useful controlling biofilm dependent diseases related to this microrganism (AU)

• FAPESP's process: 09/12354-6 - Evaluation of antimicrobial potential and in vitro activity on the dental biofilm by isolated compounds from melipolinea propolis (Melipona scutellaris)
• Grantee: Marcos Guilherme da Cunha
• Support Opportunities: Scholarships in Brazil - Master