Evaluation of antimicrobial activity of extracts of Tibouchina candolleana (melastomataceae), isolated compounds and semi-synthetic derivatives against endodontic bacteria

Abstract

This work describes the phytochemical study of the extracts from aerial parts of Tibouchina candolleana as well as the evaluation of the antimicrobial activity of extracts, isolated compounds, and semi-synthetic derivatives of ursolic acid against endodontic bacteria. HRGC analysis of the n-hexane extract of T. candolleana allowed identification of β-amyrin, α-amyrin, and β-sitosterol as major constituents. The triterpenes ursolic acid and oleanolic acid were isolated from the methylene chloride extract and identified. In addition, the flavonoids luteolin and genistein were isolated from the ethanol extract and identified. The antimicrobial activity was investigated via determination of the minimum inhibitory concentration (MIC) using the broth microdilution method. Amongst the isolated compounds, ursolic acid was the most effective against the selected endodontic bacteria. As for the semi-synthetic ursolic acid derivatives, only the methyl ester derivative potentiated the activity against Bacteroides fragilis.

Phytochemical study and antioxidant, antimicrobial and anticancer activities of Melanelia subaurifera and Melanelia fuliginosa lichens

“…It was also observed that the tested extract was inactive against E.coli, whereas the isolated compound exhibited a antimicrobial effect. However, in several previous experiments (Schinor et al 2007;Dos Santos et al 2012) also it has been found that the extracts do not inhibit the grow of microorganisms, but their isolated compounds demonstrate an antimicrobial effect. This is because components are present in the extract act antagonistically and thus reduce the activity of the extract.…”

Antibacterial activity of Pinus elliottii against anaerobic bacteria present in primary endodontic infections

“…Indeed, they possess antibacterial activity against aerobic and anaerobic pathogens of the oral cavity [2,9,11,12,25,31,32]. Therefore, this study aimed to verify the antibacterial activity of the oleoresin, fractions, subfractions, and the major compound dehydroabietic acid isolated from P. elliottii against bacteria that cause endodontic infections.…”

Anti-Leishmanial, Anti-Inflammatory and Antimicrobial Activities of Phenolic Derivatives fromTibouchina paratropica

“…Compounds extracted from various members of this genus show bioactive properties (Cruz and Kaplan, ). Antibacterial (Mosquera et al ., ; Scio et al ., ; dos Santos et al ., ), antifungal (Niño et al ., ; Kuster et al ., ), anti‐oxidant (Mosquera et al ., ; Scio et al ., ; Sirat et al ., ), anticancer (Jones et al ., ) and anti‐parasitic activit ies (Singha et al ., ; Mpalantinos et al ., ; Cunha et al ., ) have been reported.…”