ABSTRACT
O presente trabalho procurou avaliar a qualidade de produtos comercializados à base de boldo, pata-de-vaca e ginco, através dos parâmetros contidos na Farmacopéia Brasileira e na literatura específica. Foram analisadas oito amostras de boldo, nove de pata-de-vaca e sete de ginco, adquiridas em farmácias na cidade do Recife. A metodologia consistiu em avaliar: os rótulos e bulas dos produtos verificando se estavam de acordo com a RDC n o 17 de 24/02/2000 e a portaria 110/97 da ANVISA; realizar análise sensorial; verificar a autenticidade das amostras e sua pureza. Todas as embalagens de boldo, pata-de-vaca e seis de ginco continham erros ou ausência de informações científicas, além da falta de bula. Na verificação de impurezas, todas as de boldo, cinco de pata-de-vaca, e uma amostra de ginco foram reprovadas. Todos os produtos analisados apresentaram alguma irregularidade segundo os códigos oficiais, sendo necessário uma maior intensificação na vigilância de produtos à base de plantas medicinais no Brasil.
This study aimed to evaluate the quality of commercial products prepared with boldo (Peumus boldus Molina), pata-de-vaca (Bauhinia spp.) and ginkgo (Ginkgo biloba L.) by using parameters from the Brazilian Pharmacopoeia and specific literature. Eight samples of "boldo", nine of "pata-de-vaca", and seven of ginkgo were analyzed, all bought from pharmacies in Recife (Pernambuco, Brazil). The methodology consisted in evaluating the products labels and instructions to verify their accordance to RDC n o 17 of 02/24/2000 and ANVISA (National Sanitary Surveillance Agency) decree 110/97, undertaking a sensorial analysis, and verifying the authenticity and purity of the samples. All of the packages of "boldo" and "pata-de-vaca" and six of the packages of ginkgo contained mistakes or lacked scientific information; instructions were also missing. After analyzing for impurities, all samples of "boldo", five of "pata-de-vaca", and one of ginkgo were rejected. All of the products analyzed had some sort of irregularity in relation to the official codes, making it necessary to intensify the inspection of medicinal plant products in Brazil.
ABSTRACT
Many pharmacological effects have been ascribed to extracts of Psidium guajava L. (guava) leaves. However, in spite of its widespread use in Brazilian folk medicine and a reasonable number of scientific reports about it, we could not find any study dealing with its action on the mammalian myocardium. In the present study, by measuring isometric force, we observed that the crude extract of P. guajava (water-alcohol extract obtained by macerating dry leaves) depresses the guinea pig atrial contractility in a concentration-dependent fashion (N = 8 hearts, 15 trials). The compound with cardiac activity was concentrated by extraction in a Soxhlet apparatus using 17 M glacial acetic acid after removing the less polar fractions (hexane, chloroform, acetone, ethanol and methanol), suggesting that this compound is a highly polar substance. In the isolated guinea pig left atrium the acetic acid fraction (10-800 mg/l) of P. guajava 1) reversibly decreased myocardial force in a concentration-dependent fashion (EC50 = 0.07g/l, N = 5 hearts, 9 trials, P<0.05), 2) increased the atrial relaxation time measured at 20 percent of the force amplitude up to 35 percent (91 ± 15 to 123 ± 30 ms, N = 3 hearts, 6 trials, P<0.05), 3) abolished the positive staircase effect (Bowditch phenomenon) in a concentration-dependent fashion suggesting a decrease of the cellular inward calcium current (N = 4 hearts, 8 trials, P<0.05), and 4) its inotropic effect was abolished by cholinergic receptor blockade with 1.5 mM atropine sulfate, indicating a cholinergic involvement in the mechanism of action of the extract (N = 7 hearts, 15 trials, P<0.05). The acetic acid extract was 20 times more potent than crude extract (EC50 = 1.4 g/l). The results showed that extracts from P. guajava leaves depress myocardial inotropism