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| Author(s): |
Cristiane Teixeira Vilhena Bernardes
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | Ribeirão Preto. |
| Institution: | Universidade de São Paulo (USP). Faculdade de Ciências Farmacêuticas de Ribeirão Preto (PCARP/BC) |
| Defense date: | 2014-09-19 |
| Examining board members: |
Jairo Kenupp Bastos;
Hosana Maria Debonsi;
Carlos Henrique Gomes Martins
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| Advisor: | Jairo Kenupp Bastos |
| Abstract | |
Baccharis dracunculifolia (Asteraceae) popularly known as \"alecrim do campo\" is a woody shrub, native from the southeast of Brazil, widely used in folk medicine for the treatment of inflammatory and gastrointestinal diseases. Antibacterial, antifungal and anti-parasitic activities were also reported. Pinus elliottii is an exotic species that was introduced in southeast of Brazil as a reforestation specie and spread rapidly. Pinus plants are rich in phenolic components and terpenes, and some diterpenes display antimicrobial activity. With the resurgence of antimicrobial resistant microorganisms, there is a growing interest in investigating new substances for the treatment of topical and systemic infections, as well as the development of sterilizing or antiseptic products to be used in domestic, industrial and hospital. In the present study we have obtained the extracts of aerial parts (BD) and roots (BD-R) of B. dracunculifolia, by maceration process using aqueous ethanol 96:4, along with its leaves rinsed extract (BD- L). The extracts were submitted to different chromatographic techniques and the obtained fractions and isolated compounds were submitted to antimicrobial evaluation. The BD extract was partitioned using an apparatus for high-speed countercurrent chromatography, followed by preparative HPLC, furnishing the flavone hispidulin, flavononol aromadendrin-4-O-metyl-ether and the phenylpropanoid p-coumaric acid. The BD-RH fraction was subjected to fractionation by classical column and two of the resulting fractions were subjected to recrystallization process furnishing the triterpenes baccharis oxide and friedelinol. Fractions from BD-L extract were submitted to fractionation by vacuum liquid chromatography (CLV), classical column and preparative HPLC furnishing the flavanone isosakuranetin and flavonol 3 - O - methyl - kaempferol. The P. elliottii the resin was subjected to hydrodistillation in Clevenger for the separation of its volatile fraction, and decoction water was partitioned with EtOAc to furnish the fixed components fraction of P. elliottii resin (PE extract), which was submitted to preparative HPLC to furnish dehydroabietic acid. The activity of BD and PE extracts were determined against Mycobacterium avium, M. kansasii, M. smegmatis, M. tuberculosis and M. bovis, using the methodology for determining the minimum inhibitory concentration (MIC). Both extracts showed activity against all mycobacteria tested, except for the BD extract against M. smegmatis. It was also evaluated the antibacterial and antifungal activities of the B. dracunculifolia extract, fractions, isolated and commercial available compounds along with BD-R, BD-L and dehydroabietic acid. The antimicrobial activities were evaluated by MIC determination against the bacterias S. aureus, P. aeruginosa, S. choleraesuis, E. coli, B. subtilis, H. pylori and fungi T. mentagrophytes and C. albicans. Neither extract nor B. dracunculifolia fraction were active against Gram negative microorganisms, except isosakuranetin that was active against S. choleraesuis, but not with bactericidal activity. PE extract was active against all microorganisms assessed, except for E. coli. The dehydroabietic acid was active against all microorganisms except for Gram negative bacteria. B. dracunculifolia extract were combined with P. elliottii extract, as well as in sub-inhibitory concentrations, in combination with antimicrobial drugs, against the same tested microorganisms. It was observed a negative interaction of all extracts and fractions of B. dracunculifolia with the antifungal ketoconazole, which displayed higher MIC values when combined. Only PE extract lead to a reduction in MIC values in combination with ketoconazole. However, for antifungal fluconazole all samples diminished the MIC values. The best result iv was observed when fluconazole was associated with BD EtOAc fraction (50 ?g/mL) leading to a reduction of MIC values from 512 ?g/mL to 2 ?g/mL, which should be consider for further development to face antimicrobial resistance. It was assessed the potential bactericidal disinfectant potential of B. dracunculifolia extract 0.2% in 40 ºGL alcohol, which was effective against S. aureus, P. aeruginosa, S. choleraesuis and E. coli. I was also evaluated the disinfectant fungicidal activity of the hydroalcoholic solutions of 0.2% B. dracunculifolia and. P. elliottii, extracts in 40º GL, as well as the 40 ºGL alcohol solution as control. Both extracts solutions were active against T. mentagrophytes, and the control was not active. The activities of 0.2% extracts in alcohol 40 º GL were better than those observed in the MIC determination without ethanol. Therefore, it is suggest that ethanol 40º GL is acting as an adjuvant allowing better activity of the extract. Solutions of B. dracunculifolia and P. elliottii extracts, alone and in combination were inactive in the sporicidal disinfectant assay against B. subtilis and C. sporogenes. Overall, the two plants have the potential for the development of antimicrobial products, especially with regards to the synergistic effect of the extracts in combination with fluconazole. (AU) | |
| FAPESP's process: | 10/09861-0 - Evaluation of antimicrobial, antiseptic and sterilizing activities of extract and metabolite of Baccharis dracunculifolia and Pinus elliottii. |
| Grantee: | Cristiane Teixeira Vilhena Bernardes |
| Support Opportunities: | Scholarships in Brazil - Doctorate |