Estudio fitoquímico y control de calidad de extractos de hojas de Rheedia aristata Griseb / Phytochemical study and quality control of extracts from leaves of Rheedia aristata Griseb

Introducción: tradicionalmente, los campesinos han empleado la resina del fuste de Rheedia aristata Griseb. para extraer espinas encarnadas y en la cura de enfermedades respiratorias como el asma y la pulmonitis. Objetivo: identificar los metabolitos secundarios presentes en la decocción, tintura 20 por ciento y el extracto fluido de hojas de Rheedia aristata Griseb., y establecer la estabilidad de la tintura 20 por ciento y del extracto fluido. Métodos: se recolectaron partes aéreas, se lavaron, desinfectaron, secaron, y pulverizaron. De estas se obtuvieron la decocción, tintura 20 por ciento y el extracto fluido, los cuales se filtraron. Finalmente, se realizaron ensayos fitoquímicos y control de calidad.Resultados: el tamizaje fitoquímico confirma la existencia de varias familias de metabolitos secundarios de interés biológico y farmacológico; entre otras, saponinas, quinonas, coumarinas y alcaloides. Los ensayos del control de calidad mostraron que son estables la tintura 20 por ciento y el extracto fluido bajo las condiciones aplicadas. Conclusiones: la tintura 20 por ciento y el extracto fluido de las hojas de Rheedia aristata son formulados ricos en metabolitos secundarios, que pudieran ser los principios activos responsables del uso como medicamento, reportado en estudios etnobotánicos. Esto, unido a la gran estabilidad que muestran y a la no existencia de reportes de toxicidad, convierten a esta planta en fuente potencial de fitomedicamentos

Introduction: traditionally, farmers have used the resin of the shaft of Rheedia aristata Griseb. to remove penetrated thorns in the body and cure respiratory diseases such as asthma and lung inflammatory process. Objective: to identify the secondary metabolites in the decoction, tincture at 20 percent and fluid extract of the leaves of Rheedia aristata Griseb. and to establish the tincture and the fluid extract stability at a 20 percent. Methods: air parts of the plant were collected; they were washed, disinfected, dried and pulverized. The decoction, tincture at 20 percent, and extract were obtained and they were filtered. Finally, phytochemical screenings and quality control tests were performed. Results: phytochemical screening confirms the existence of several families of secondary metabolites of biological and pharmacological interest; among others, saponins, quinones, coumarins and alkaloids. The quality control tests carried out to the tincture at 20 percent and flowing extract indicated that, under the conditions applied, the elaborated products are stable. Conclusions: the 20 percent tincture and the fluid extract of the leaves of Rheedia aristata are rich formulations in secondary metabolites that could be the active principles responsible for the use of the plant as medicine, as reported in ethnobotanical studies. This fact, together with the great stability and absence of toxicity reports, converts this plant in a potential source of phytomedicines

Estudo in vitro da atividade do extrato etanólico de sementes de bacupari (Rheedia gardneriana Planch. & Triana) e das frações no crescimento de Streptococcus mutans / In vitro study of the activity of ethanol extract from bacupari (Rheedia gardneriana Planch. & Triana) seeds and its fractions on Streptococcus mutans growth

Streptococcus mutans, principal microrganismo da cavidade oral, desempenha papel preponderante na formação de placas dentárias, sendo considerado o agente etiológico primário da cárie. Rheedia gardneriana, conhecida popularmente como bacupari, é uma planta utilizada com fins medicinais para o tratamento de diversas patologias, e por apresentar atividade antimicrobiana de compostos das folhas contra bactérias Gram-positivas e Gram-negativas. O objetivo do presente trabalho foi avaliar o efeito de extrato de semente de R. gardneriana sobre a cepa S. mutans UA159. Os testes foram conduzidos com o extrato etanólico bruto e as frações obtidas com os solventes diclorometano, etanol-água, metanol e hexano, em ensaios de inibição in vitro. O extrato bruto (100 por cento) apresentou halos de inibição com diâmetro similar ao obtido com solução de digluconato de clorexidina 0,12 por cento, usada como controle. Os ensaios com a fração diclorometano exibiram atividade inibitória 35 por cento menor comparado com o controle, enquanto nenhum efeito antimicrobiano foi observado com a fração etanol-água. Contrariamente, os resultados obtidos com as frações hexânica e metanólica demonstraram claramente a atividade antimicrobiana por inibição do crescimento bacteriano. Na fração metanólica a formação de halos de inibição foi similar ao do controle. Estes dados apresentam atividade antimicrobiana de R. gardneriana contra S. mutans.

Streptococcus mutans, which is the main microorganism of the oral cavity, plays a preponderant role in dental plaque formation and is considered the primary etiologic agent regarding caries. Commonly known as "bacupari", Rheedia gardneriana is a plant used for medicinal purposes in the treatment of several pathologies; besides, its leaves have compounds that present antimicrobial activity against Gram-positive and Gram-negative bacteria. The aim of this work was to evaluate the effect of R. gardneriana seed extract on S. mutans strain UA159. The tests were carried out with crude ethanol extract and the fractions obtained with the solvents dichloromethane, ethanol-water, methanol, and hexane in in vitro inhibition assays. The crude extract (100 percent) presented inhibition halos with diameter similar to that obtained by using 0.12 percent chlorhexidine digluconate solution as control. Assays with the fraction dichloromethane showed an inhibitory activity 35 percent lower than that of the control, whereas no antimicrobial effect was observed with the ethanol-water fraction. Conversely, the results obtained with the fractions hexane and methanol clearly demonstrated antimicrobial activity by inhibiting the bacterial growth. In the methanol fraction, the formation of inhibition halos was similar to that in the control. These data present antimicrobial activity of R. gardneriana against S. mutans.

PRENYLATED XANTHONES FROM Rheedia acuminata (reprinted from Acta Amazônica, 23(2/3):181-185)

Pyranojacareubin; 1,5-dihydroxy-6',6'-dimethyl-2H-pyran(2,,3':6,7) -6",6"-dime-thyl-2H,4H-pyran(2",3":2,3)xanthone and a new xanthone l,6-dihydroxy-5-methoxy-6',6'-dime-thyl-2H-pyran(2',3':3,2)-7-(3,3-dimethylprop-2-enyl)xanthone were isolated from the ether extract of the root bark of Rheedia acuminata together with friedelin and friedelanol.

Piranojacareubina; 1,5-diidroxi-6',6'-dimetil-2H-pirano(2',3':6,7)-6",6"-dimetil-2H,4H(2",3":2,3)xantona e uma xantona inédita 1,6-diidroxi-5-metoxi-6,6'-dimetil-2H-pirano(2',3':3,2)-7-(3,3-dimetilprop-2-enil) xantona foram isoladas do extrato etèreo da casca da raiz de Rheedia acuminata além de friedelina e friedelanol.

ena acuminata

Pyranojacareubin; 1,5-dihydroxy-6',6'-dimethyl-2H-pyran(2',3':6,7) -6",6"-dim-ethyI-2H,4H-pyran(2",3":2,3)xanthone and a new xanthone l,6-dihydroxy-5-methoxy-6',6'-dim-ethyl-2H-pyran(2',3':3,2)-7-(3,3-dimethylprop-2-enyl)xanthone were isolated from the ether extract of the root bark of Rheedia acuminata together with friedelin and friedelanol.

Piranojacareubina;l,5-diidroxi-6',6'-dimetil-2H-pirano(2',3':6,7)-6",6"-dimetil-2H,4H(2",3":2,3)xantona e uma xantona inédita l,6-diidroxi-5-metoxi-6',6'-dimetil-2H-pirano(2',3':3,2)-7-(3,3-dimetilprop-2-enil) xantona foram isoladas do extrato etéreo da casca da raiz de Rheedia acuminata além de friedelina e friedelanol.