ABSTRACT
Herbal medicines have been studied as potential antimicrobial agents, emerging as treatments against oral diseases. The current study evaluated the antimicrobial activity of the crude extract and fractions of Mikania laevigata SchultzBip. ex Baker (ML) and Varronia curassavicaJacq (VC) against oral pathogens associated with persistent dental root infections, under planktonic and biofilm conditions. Minimal inhibitory concentrations and minimal bactericidal/fungicidal concentrations were determined for the ML and VC fractions/extracts against Enterococcus faecalis, Actinomyces israelii, Pseudomonas aeruginosa, and Candida albicans using the microdilution method. The best results were chosen for subsequent biofilm assays. All tested ML and VC extracts/fractions demonstrated inhibitory activity against E. faecalis and A. israelii. The ML ethyl acetate fraction affected the growth of all microorganisms tested. C. albicans and P. aeruginosawere not affected by any VC extract/fractions. The ML ethyl acetate fraction eliminated E. faecalis, A.israelii, and P. aeruginosa biofilms after 24h. A similar result was observed for ML crude hydroethanolic extract and its hexane fraction for A. israelii. The VC hexane fraction was able to eliminate A. israelli biofilms. None of the tested extracts or fractions eliminated C. albicans biofilm. The Mikania laevigata ethyl acetate fraction is an efficient antimicrobial agent against oral pathogens and could be indicated for the treatment of persistent dental infections.
Subject(s)
Mediation AnalysisABSTRACT
O objetivo deste trabalho foi avaliar a atividade antimicrobiana e o efeito citotóxico do óleo essencial (OE) de capim-limão (Cymbopogon citratus). A partir do método de difusão em ágar, diferentes concentrações de OE (0,1%; 0,2% e 1%), e soluções controle (clorexidina (Chx), água destilada (Ad) e álcool de cereais (Ac) foram aplicados sobre culturas de Candida albicans (C.a), Streptococos mutans (S.m), Streptococos sobrinus (S.sob) e Lactobacilus acidoflus (L.a). Para C.a, S.m e S.sob, os maiores halos de inibição, em ordem decrescente foram: Chx, Ac e óleo 1%, sendo os dois últimos semelhantes estatisticamente (Mann-Whitney, p>0,05). Para L.a, o maior halo de inibição foi observado para a Chx, seguido do óleo a 1%, 0,2%, 0,1% e Ac. Para avaliação da citotoxicidade foram determinados os seguintes grupos: OE a 0,1%; G2: OE puro; G3 (controle positivo): H2O2; G4: álcool de cereais (Ac); e G5 (controle negativo): meio de cultura (DMEM). As soluções foram aplicadas sobre cultura de células MDPC-23 (30.000 células/cm2) semeadas em placas de 24 wells. O metabolismo celular foi avaliado pelo teste do MTT. Considerando G5 como 100% de metabolismo celular, foi observado para os grupos G1, G2, G3, e G4 uma redução percentual no metabolismo das células de 29,6%; 82%; 81,2%; e 33,4%, respectivamente. Concluiu-se que o OE a 0,1% foi capaz de inibir o crescimento das cepas avaliadas e de causar discreta citotoxicidade sobre células odontoblastóides MDPC-23.
The aim of this study was to evaluate the antimicrobial and cytotoxic efect of essential oil (EO) of lemon grass (Cymbo-pogon citratus). From the agar difusion method, diferent concentrations of EO (0.135%, 0.2% and 1%), and control solutions (chlorhexidine (Chx), distilled water (Ad) and cereal alcohol (Ac)) were applied on cultures of Candida albicans (C.a), Streptococcus mutans (S.m), Streptococcus sobrinus (S.sob) and Lacto-bacillus acidophilus (L.a). For C.a, S.m and S.sob, the largest inhibition zones in descending order were: Chx, Ac and EO 1%, while the later two were statistically similar (Mann-Whitney, p> 0.05). For L.a, the largest inhibition halo was observed for the Chx, followed by EO at 1%, 0.2%, 0.135% and Ac. For evaluation of cytotoxicity, the following groups were set: G1: 0,1% EO; G2: pure EO; G3 (positive control): H2O2; G4: cereal alcohol; and G5 (negative control): culture medium - DMEM. The solutions were applied on the cultured MDPC-23 cells, which were plated (30,000 cells/cm2) in wells of 24 well-dishes. Cell metabolism was evaluated by MTT assay. Considering G5 (negative control) as 100% of cell metabolism, it was observed for G1, G2, G3 and G4 a percentage reduction in cell metabolism of 29.6%, 82%, 81.2% and 33.4%, respectively. It was concluded that the low concentration of 0,1% OE (C. citratus) was able to inhibit the growth of the strains tested as well as caused mild cytotoxicity to the cultured MDPC-23 cells.
ABSTRACT
In this work, chemical and biological activities of crude extracts obtained with 50 percent ethanol, 70 percent ethanol, acetone:water (7:3; v/v) and chloroform of Plinia cauliflora (DC.) Kausel, Myrtaceae, leaves, a native tree from several regions of Brazil, was investigated. Histochemical and phytochemical screenings were done according to characterization reactions and thin layer chromatography. To assist in extracts standardization, total phenol and flavonoids content spectrophotometric was performed. Antioxidant activity was analyzed by percentage of radical scavenging using DPPH solution. Antimicrobial activity was evaluated against Gram-positive, Gram-negative pathogenic bacteria and species of Candida using agar diffusion and minimal inhibitory concentration (MIC) determination methods according to standard methods. The leaves presented lipids at secretory cavity and phenols, mainly tannins, in nervures and palisade parenchyma. Polar extracts showed flavonoids, tannins and high content of phenols and flavonoids. The extracts showed great antioxidant activity and antimicrobial activity was better against Candida species than against bacteria.
No presente trabalho, foram investigadas a composição química e atividades biológicas de extratos brutos obtidos com etanol 50 por cento, etanol 70 por cento, acetona:água (7:3; v/v) e clorofórmio das folhas de Plinia cauliflora (DC.) Kausel, Myrtaceae, uma árvore nativa de várias regiões do Brasil. Os rastreamentos histoquímico e fitoquímico foram feitos de acordo com reações de caracterização e cromatografia em camada delgada. Para auxiliar na padronização dos extratos foram realizadas determinações do teor de fenóis totais e de flavonoides totais, espectrofotometricamente. A atividade antioxidante foi analisada pela porcentagem de sequestro de radicais livres usando solução de DPPH. A atividade antimicrobiana foi avaliada frente a bactérias patogênicas Gram-positivas, Gram-negativas e espécies de Candida utilizando os métodos de difusão em ágar e determinação da concentração inibitória mínima (MIC) de acordo com métodos padronizados. As folhas apresentaram lipídeos nas cavidades secretoras e fenóis, principalmente taninos, nas nervuras e parênquima paliçádico. Os extratos polares apresentaram flavonoides, taninos, alto teor de fenóis totais e de flavonoides totais. Os extratos mostraram elevada atividade antioxidante e a atividade antimicrobiana foi melhor contra as espécies de Candida do que contra as bactérias.
ABSTRACT
Considerando-se a qualidade dos fitoterápicos, é importante salientar que a preocupação com esta questão inclui rigoroso acompanhamento das diferentes etapas do desenvolvimento e produção destes produtos, desde a coleta do vegetal até a disponibilidade do produto final. Neste trabalho foi realizado o controle da qualidade do fruto de Syzygium cumini (L.) Skeels, popularmente conhecido como jambolão. Para o controle físico-químico e microbiológico utilizaram-se metodologias farmacopéicas e não farmacopeicas. Os resultados obtidos mostraram que o fruto apresenta um teor de taninos de 4,2 por cento e a análise fitoquímica preliminar dos frutos de S. cumini evidenciou taninos, flavonóides, antocianidinas, iridóides, alcalóides e heterosídeos fenólicos simples. A análise microbiológica não apresentou crescimento de patógenos entre os outros testes realizados. Destaca-se a importância do estabelecimento de normas para o controle da qualidade para as plantas, a fim de que sejam utilizadas com finalidade fitoterápica.
Considering the quality of the phytotherapic agents, it is important to point out that the concern with this subject includes rigorous attendance of the different steps of the development and production of these products, from the collection of the vegetable to the availability of the final product. In this work the quality control of the Syzygium cumini (L.) Skeels fruit, popularly known as jambolão, was carried out. Pharmacopoeic and no pharmacopoeic methodologies were employed to physico-chemical and microbiological quality control. The obtained results showed that the fruits presents a content of tannins of 4.2 percent, the preliminary phytochemical analysis of the S. cumini fruits evidenced tannins, flavonoids, antocianidin, iridoids, alkaloids and heterosides simple phenols. The microbiological analysis didnÆt present phatogenic growth among the other accomplished tests. The work stands out the importance of the establishment of norms for the quality control for the plants, so that they are used with phytotherapic purpose.