Substâncias de origem vegetal potencialmente úteis na terapia da asma

RESUMO:Adulterações da matéria-prima vegetal ocorrem comumente no mercado de fitoterápicos, sob a forma de substituições e/ou falsificações. Muitas vezes, espécies distintas são comercializadas em substituição à farmacopéica devido à dificuldade de obtenção desta, ou mesmo pelo emprego intencional de espécies de menor valor econômico que apresentem características morfológicas semelhantes. Portanto, faz-se necessária a realização de estudos que busquem identificar a constituição química das espécies de amplo uso medicinal, que são alvos de adulterações. Mikania glomerata e Mikania laevigata, conhecidas popularmente como "guaco", são comercializadas indistintamente. Buscando-se avaliar a composição química das duas espécies, realizou-se uma prospecção fitoquímica por CCD e foram obtidos os perfis cromatográficos por CLAE-FR. Fez-se a quantificação da cumarina empregando-se o mesmo método. Na prospecção fitoquímica por CCD, foi detectada, nas duas espécies, a presença de cumarina, triterpenos/ esteróides e heterosídeos flavônicos. Os perfis cromatográficos, obtidos por CLAE-FR, mostraramse semelhantes, observando-se a predominância de compostos polares. Na quantificação da cumarina, obtêve-se um teor de 0,30% para M. glomerata e 0,43% para M. laevigata, teores de acordo com o preconizado na monografia do guaco-cheiroso (mín. 0,1%). M glomerata e M. laevigata apresentaram composição química semelhante e teores de cumarina próximos, sugerindo que estas podem ser utilizadas de forma indistinta.Unitermos: Mikania glomerata, Mikania laevigata, Asteraceae, guaco, cumarina.ABSTRACT: "Comparative study of the chemical composition of the species Mikania glomerata Sprengel and Mikania laevigata Schultz Bip. ex Baker". Adulterations of plant raw materials often occur in the marketing of herbal medicine, usually in the form of substitutions and/ or fakes. Many times, different plant species are commercialized in the place of the one recognized by the pharmacopoeia. This may occur due to the difficulties of obtaining the authentic plant material, or by an intentional use of a plant species that has less economic value but shows similar morphologic features. Therefore, it is necessary to carry out studies that can identify the chemical composition of those species of wide medicinal use, which are the targets of adulterations. Mikania glomerata and Mikania laevigata, popularly known as "guaco", are indistinctly commercialized in Brazil. A phytochemical screening by TLC was carried out to evaluate the chemical composition of both species. The RP-HPLC profiles were obtained and the quantification of coumarin was determined by the same method. A phytochemical screening has shown that coumarin, triterpenes/ steroids and flavonic heterosides are the constituents detected in both species. The RP-HPLC profiles were similar between the two species and revealed the predominance of polar compounds. In the quantification of coumarin, a content of 0.30% (w/w) was obtained for M. glomerata and 0.43% (w/w) for M. laevigata. These values are i...

Section: Introductionunclassified

Estudo comparativo da composição química das espécies vegetais Mikania glomerata Sprengel e Mikania laevigata Schultz Bip. ex Baker

Bolina¹,

Garcia²,

Duarte³

2009

“…Segundo a Organização Mundial da Saúde (OMS), as plantas medicinais são as melhores fontes para se obter uma variedade de medicamentos, e cerca de Rafael C. Dutra, Fernanda G. Braga, Elaine S. Coimbra, Adilson D. Silva, Nádia R. Barbosa 80% da população mundial usa a medicina tradicional na busca de alívio de alguma sintomatologia dolorosa ou desagradável (Nascimento et al, 2000;Caetano et al, 2002;Corrêa et al, 2008;Sousa et al, 2008). A seleção de plantas, a partir de informações da medicina tradicional ou popular, pode conduzir a descoberta de moléculas promissoras com ação terapêutica (Agra et al, 2007).…”

Section: Introductionunclassified

Atividades antimicrobiana e leishmanicida das sementes de Pterodon emarginatus Vogel

Dutra¹,

Braga²,

Coimbra³

et al. 2009

"Antimicrobial and leishmanicidal activities of seeds of Pterodon emarginatus". The present work investigated the antimicrobial and leishmanicidal activities of seeds of Pterodon emarginatus. The tests of diffusion in agar (10, 25 and 50 mg) and determination of minimum inhibitory concentration (MIC) were performed using essential oil (EO) obtained from seeds using the standard microorganisms: Staphylococcus aureus ATCC 25923, Streptococcus mutans ATCC 25175, Pseudomonas aeruginosa ATCC 90271, Escherichia coli ATCC 10530 and Candida albicans ATCC 10231. Leishmanicidal activity of the EO and fractions (6.25 -100 μg/ml) obtained of seeds of P. emarginatus was evaluated in vitro using L. amazonensis and L. chagasi promastigote forms. The EO inhibited the growth of S. aureus (MIC = 2.5 mg/ml). The hexane (IC 50 = 50.06 µg/ ml) and butanol (IC 50 = 46.65 µg/ml) fractions showed activity against L. amazonensis promastigote forms, but did not against L. chagasi promastigote forms. The results indicate that the bioactive molecules present in the seeds of P. emarginatus can be used as prototype for the development of drug and/or as source pharmaceutical material.

“…Studies reported by Soares de Moura et al (2001) and Corrêa et al (2008) supported the indication of M. glomerata products for the treatment of respiratory diseases where broncoconstriction is present, while Fierro et al (1999) showed the anti-allergenic effects of guaco extract. The described biological effects are mainly due to the presence of coumarin in this plant (Vilegas et al, 1997b;Rocha et al, 2008).…”

Section: Introductionmentioning

confidence: 71%

A validated capillary gas chromatography method for guaco (Mikania glomerata S.) quality control and rastreability: from plant biomass to phytomedicines

Bueno¹,

Bastos²

2009

A validated capillary gas chromatography method for guaco (Mikania glomerata S.) quality control and rastreability: from plant biomass to phytomedicines ABSTRACT: This work describes a full validation of a capillary gas chromatography analytical methodology using internal standardization for the quantification of coumarin (1,2-benzopyrone) in guaco (Mikania glomerata Spreng -Asteraceae) products: syrup, plant and its extract, including the stability study of the phytomedicine. For the analysis, it was used an HP-5 capillary column (30 m x 0.32 mm x 0.25 µm), hydrogen at a flow rate of 1.8 mL/min and the increasing temperature gradient was: 100 °C to 250 °C, 15 ºC/min. The temperature of injector (split 1:20) and detector were kept at 250 °C and 270 °C, respectively. The retention times of the standards for the above conditions were 2.86 minutes for 1, 2, 3, 4-tetramethylbenzene, 4.45 min for piperonal (internal standards), and 5.36 minutes for coumarin. After extraction procedure, the recovery of coumarin determined for plant raw material was 101.6 %, while for syrup it was 100.8 %. Detection and quantification limits were 0.5 µg/mL and 1.5 µg/mL, respectively. Precision was determined for all samples and the results were lower than 2.5 %. The total amount of coumarin in plant raw material, its extract and syrup were 0.38 % w/w, 1.33 mg/mL and 0.143 mg/mL, respectively.