Medicinal plants from the genus Alchornea (Euphorbiaceae): a review of their ethnopharmacology uses and phytochemistry / Plantas Medicinales del género Alchornea (Euphorbiaceae): Review de los usos etnofarmacológicos y fitoquímicos

The genus Alchornea compromises 55 accepted and other two unresolved species (Alchornea acerifera Croizat and Alchornea oblonga Müll. Arg.) which well various ecosystems over all the continents, with a special pantropical distribution. Numerous reports of ethnopharmacological uses of species belonging this genus exist mainly in Africa and Brazil, to treat different inflammatory and infectious diseases: arthritis, dysentery, infectious diseases, inflammation, intestinal disorders, fractures, leprosy, malaria, management of ringworm affections, muscle pain, rheumatism and ulcer. The genus Alchornea, contains different secondary metabolites and they have been reported such as: Alkaloids, terpenes and steroids, phenolic acid, saponins, principaly. The aim of the present review is to provide gathered and organized information with pharmacological, toxicological, traditional and phytochemical traits of plants from the Alchornea genus in order to define the biological potential of the genus and to define a state-of-art-platform stating the perspectives for further pharmacological/chemotaxonomical studies.

El género Alchornea comprende 55 especies aceptadas y otras dos especies por confirmar (Alchornea acerifera Croizat y Alchornea oblonga Müll. Arg.) qué habitan en diversos ecosistemas en todos los continentes, con una distribución pantropical especial. Existen numerosos reportes de usos ethnofarmacologicos de especies que pertenecen a este género en Africa y Brasil, en el tratamiento de diferentes enfermedades inflamatorias e infecciosas: la artritis, la disentería, los desórdenes intestinales, las fracturas, la lepra, la malaria, dolor del músculo, reumatismo y úlcera. En el género Alchornea, se han reportado diversos tipos de metabolitos secundarios tales como: alcaloides, terpenos y esteroides, ácidos fenolicos, saponinas, principalmente. El objetivo de esta revisión fue de compendiar y organizar la información farmacológica, toxicológica, de usos tradicionales y de fitocompuestos de plantas del género de Alchornea en el orden de definir el potencial biológico del género y establecer la plataforma del estado-de-arte con las perspectivas de los futuros estudios farmacológico/quimiotaxonómicos que se podrían realizar.

Apigenin glycoside: an antioxidant isolated from Alchornea coelophylla pax & k. Hoffm. (euphorbiaceae) leaf extract / Glicósido de apigenina: un antioxidante aislado del extracto de hoja de Alchornea coelophylla Pax & K. Hoflm. (Euphorbiaceae) / Glicosídeo de apigenina: um antioxidante do extrato das folhas de Alchornea coelophylla Pax & K. Hoflm. (Euphorbiaceae)

Abstract An antioxidant flavonoid has been isolated from methanolic leaf extract of Alchornea coelophylla Pax & K. Hoffm. by means of different column chromatography steps with DIAION HP-20 resin and silica gel in combination with analytical highperformance liquid chromatography (HPLC). It was identified as Apigenin-8-C- (α-L-rhamnopyranosyl-(1-›2)-β-D-glucopyranoside) on the basis of spectroscopic analysis and by comparison with related values reported in the literature. This compound exhibited high in vitro antioxidant activity through DPPH. and ABTS • + colorimetric assays with IC50 values of 7.528 and 379.7 µg. mL-1, respectively.

Resumen Se aisló un flavonoide antioxidante del extracto metanólico de hojas de Alchornea coelophylla Pax & K. Hoffm. El compuesto se obtuvo por medio de sucesivas cromatografías en columna (con la resina DIAION HP-20 y sílica gel), seguidas de cromatografía líquida de alta eficiencia (HPLC). Con base en el análisis espectroscópico y por comparación con valores relacionados reportados en la literatura, el flavonoide se identificó como Apigenin-8-C-(α-L-rhamnopiranosil-(1-›2)-β-D-glucopiranósido). Este compuesto presentó una alta actividad antioxidante in vitro: ensayos colorimétricos utilizando DPPH. y ABTS • + mostraron valores de IC50 de 7.528 y 379.7 µg mL-1, respectivamente.

Resumen Um flavonoide antioxidante foi isolado do extrato metanólico das folhas de Alchornea coelophylla Pax & K. Hoffm. por meio de diferentes etapas de cromatografia em coluna usando resina DIAION HP-20 e gel de sílica em combinação com Cromatografia Líquida de Alta Eficiencia (HPLC) analítica. O composto foi identificado como apigenina-8-C-(α-L-ramnopiranosil-(1-›2)-β-D-glicopiranosido) com base em análises espectroscópicas e por comparação com valores descritos na literatura. Este composto exibiu elevada atividade antioxidante in vitro por meio de ensaios colorimétricos por DPPH e ABTS • + com valores de IC50 de 7,528 e 379,7 µg. mL-1, respectivamente.

Antibacterial and antifungal activities of crude plant extracts from Colombian biodiversity

On a global scale, people have used plants to treat diseases and infections, and this has raised interest on the plant biodiversity potencial in the search of antimicrobial principles. In this work, 75 crude n-hexanes, dichloromethane and methanol extracts from the aerial parts of 25 plants belonging to four botanical families (Asteraceae, Euphorbiaceae, Rubiaceae and Solanaceae), collected at the Natural Regional Park Ucumari (Risaralda, Colombia), were evaluated for their antibacterial and antifungal activities by the agar well diffusion method. The antibacterial activities were assayed against two Gram-positive bacteria Staphylococcus aureus and Bacillus subtilis, and three Gram-negative ones named, Klebsiella pneumoniae, Escherichia coli and Pseudomonas aeruginosa. In addition, the same plant extracts were tested against the yeast Candida albicans and the fungi Aspergillus fumigatus and Fusarium solani. Overall, the plant extracts examined displayed better bactericide rather than fungicide activities. In general, the best antibacterial activity was showed by the plant extracts from the Rubiaceae family, followed in order by the extracts from the Euphorbiaceae and Solanaceae ones. It is important to emphasize the great activity displayed by the methanol extract of Alchornea coelophylla (Euphorbiaceae) that inhibited four out of five bacteria tested (B. Subtilis, P. aeruginosa, S. aureus and E. coli). Furthermore, the best Minimal Inhibitory Concentration for the extracts with antifungal activities were displayed by the dichloromethane extracts from Acalypha diversifolia and Euphorbia sp (Euphorbiaceae). The most susceptible fungus evaluated was F. Solani since 60% and 20% of the dichloromethane and methanol extracts evaluated inhibited the growth of this phytopathogenic fungus. The antimicrobial activity of the different plant extracts examined in this work could be related to the secondary metabolites contents and their interaction and susceptibility of pathogenic microorganism evaluated.

Alrededor del mundo, la gente ha usado las plantas para tratar enfermedades e infecciones, este potencial ha hecho que se incremente el interés en la biodiversidad vegetal como fuente de principios antimicrobianos. En este trabajo, se evaluaron 75 extractos crudos de n-hexano, diclorometano y metanol, obtenidos a partir de la parte aérea de 25 especies de plantas proveniente de cuatro familias botánicas (Asteraceae, Euphorbiaceae, Rubiaceae y Solanaceae), colectadas en el Parque Regional Natural Ucumari (Risaralda, Colombia); los cuales fueron evaluados por sus actividades antibacteriana y antifúngica a través del método de difusión en pozo. La actividad antibacteriana fue ensayada frente a las bacterias Gram-positivas Staphylococcus aureus y Bacillus subtilis, y las g-negativas Klebsiella pneumoniae, Escherichia coli y Pseudomonas aeruginosa. Adicionalmente, las mismas plantas fueron evaluadas frente a la levadura Candida albicans y los hongos Aspergillus fumigatus y Fusarium solani. En general, las plantas ensayadas mostraron mejor actividad antibacteriana que antifúngica; donde la familia Rubiaceae fue la que presentó mayor actividad antibacteriana, seguida por las familias Euphorbiaceae y Solanaceae. El extracto metanólico de Alchornea coelophylla (Euphorbiaceae) fue el que presentó mejor actividad antibacteriana al inhibir cuatro de las bacteria ensayadas (B. Subtilis, P. aeruginosa, S. aureus y E. coli); y los extractos de diclorometano de Acalypha diversifolia y Euphorbia sp. (Euphorbiaceae) fueron los que tuvieron la menor Concentración Mínima Inhibitoria en la actividad antifúngica. El hongo evaluado más susceptible fue F. Solani, el cual fue inhibido por el 60% y el 20% de los extractos de diclorometano y metanol, respectivamente. Se considera que la actividad biológica de estos extractos, se relaciona con los metabolitos secundarios que ellos contienen y las diferentes susceptibilidades de los microorganismos patogénicos evaluados.

Antioxidant activity of plant extracts from Colombian flora / Atividade antioxidante de extrato de plantas da flora colombiana

In this study the antioxidant activity of forty-six methanol plant extracts, from the botanical families Asteraceae, Euphorbiaceae, Melastomataceae, Rubiaceae and Solanaceae, collected at the Regional Natural Park Ucumarí (RNPU, Risaralda, Colombia), were established by using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging assay. The plant extracts that showed the greatest antioxidant activity were Phyllanthus sp. (54.0 percent, Euphorbiaceae), followed by the two species belonging to the Melastomataceae family Tibouchina grossa (47.0 percent) and Miconia lehmannii Cogn. (45.3 percent) and continuing with Lycianthes radiata (Sendt.) Bitter. (41.5 percent, Solanaceae). This is the first report on the antioxidant activity of these Colombian species.

Neste estudo a atividade antioxidante de quarenta e seis extratos metanólicos de plantas das famílias botânicas Asteraceae, Euphorbiaceae, Melastomataceae, Rubiaceae e Solanaceae, coletadas no Parque Regional Natural Ucumarí (PRNU, Risaralda, Colômbia), foi determinada usando o ensaio de captação de radical livre de 1,1 difenil-2-picrilhidrazil (DPPH). Os extratos das plantas que mostraram a maior atividade antioxidante foram Phyllanthus sp. (54.0 por cento, Euphorbiaceae), seguido por duas espécies da família de Melastomataceae Tibouchina grossa (47.0 por cento) e Miconia lehmannii Cogn. (45.3 por cento) e Lycianthes radiata (Sendt.) Bitter. (41.5 por cento, Solanaceae). Esta é a primeira informação da atividade antioxidante destas espécies.

Antioxidant activity of twenty five plants from Colombian biodiversity

The antioxidant activity of the crude n-hexane, dichloromethane, and methanol extracts from 25 species belonging to the Asteraceae, Euphorbiaceae, Rubiaceae, and Solanaceae families collected at natural reserves from the Eje Cafetero Ecorregión Colombia, were evaluated by using the spectrophotometric 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenging method. The strongest antioxidant activities were showed by the methanol and dichloromethane extracts from the Euphorbiaceae, Alchornea coelophylla (IC50 41.14 mg/l) and Acalypha platyphilla (IC50 111.99 mg/l), respectively. These two species had stronger DPPH radical scavenging activities than hydroquinone (IC50 151.19 mg/l), the positive control. The potential use of Colombian flora for their antioxidant activities is discussed.

Antibacterial, antifungal and cytotoxic activities of eight Asteraceae and two Rubiaceae plants from colombian biodiversity

Thirty crude extracts of eight plants belonging to Asteraceae and two to Rubiaceae families collected at different places from the Regional Natural Park Ucumarí (RNPU), Colombia, were tested for their antibacterial activity against two Gram-positive and two Gram-negative bacteria and three fungi. Both the antibacterial and the antimycotic activities were tested by the agar well diffusion method. The cytotoxic activity on the same plant extracts was determined through the brine shrimp lethality bioassay. The extracts from the Asteraceae family were more bioactive against Bacillus subtilis and Staphylococcus aureus. The extracts of both families studied were bioactive against the fungi Candida albicans and Fusarium solani. In addition, the extracts of Asteraceae species displayed the greatest cytotoxic activities. However, the most important specie in this research was Gonzalagunia rosea Standl (Rubiaceae) because of the strong and moderate activities of the methanol and dichloromethane extracts against C. albicans and F. solani, respectively; as well as the strong cytotoxic activity of the methanol extract. None of these ten plants has previously been reported for their biological activities.

Trinta extratos crus de oito plantas da família Asteraceae e a duas plantas da família Rubiaceae, coletadas em diferentes lugares do Parque Natural Regional Ucumarí (PNRU), Colombia, foram avaliadas quanto à atividade contra duas bactérias Gram-positivas, duas Gram-negativas e três fungos. As atividades antibacteriana e antimicótica foram determinadas pelo método de difusão em agar. A atividade citotóxica dos mesmos extratos foi determinada através do bioensaio de Artemia salina. Os extratos da família Asteraceae foram os mais bioativos contra Bacillus subtilis e Staphylococcus aureus. Os extratos de ambas famílias estudadas foram bioativos contra os fungos Candida albicans e Fusarium solani. Os extratos da família Asteraceae exibiram maior atividade citotóxica. A espécie mais importante desta pesquisa foi Gonzalagunia rosea Standl (Rubiaceae) devido à atividade intensa e moderada dos extratos de metanol e diclorometano contra F. solani e C. albicans, respectivamente, bem como a intensa atividade citotóxica do extrato metanólico. Não se encontraram estudos prévios acerca das atividades biológicas das dez plantas avaliadas nesse estudo.

In vitro inhibition of acetylcholinesterase by crude plant extracts from Colombian flora

The methanol extracts from five different plant families (Asteraceae, Euphorbiaceae, Melastomataceae, Rubiaceae, and Solanaceae) collected at Regional Natural Park Ucumarí (Colombia), were screened for their acetylcholinesterase inhibitory activity through the modified Ellman's spectrophotometric method. The best inhibitory activities on this study were shown by the extracts of Solanum leucocarpum Dunal (IC50 = 204.59 mg/l) and Witheringia coccoloboides (Damm) (IC50 = 220.68 mg/l), both plants belonging to the Solanaceae family.