Smilax domingensis Willd., Smilacaceae, known as zarzaparrilla, is a climbing shrub from Tropical America. The rhizome is popularly used in medicine as anti-inflammatory, antiseptic, and tonic. Since 1983 studies are being conducted in Guatemala for validation of the ethnobotanical uses, particularly in vitro demonstration of antimicrobial activity, using wild material, with high variability and some taxonomic problems. This article reports the taxonomic determination, cultivation of drug material, evaluation of use by in vitro and in vivo pharmacological assays, and phytochemical characterization. Extracts from cultivated material was evaluated by antimicrobial, anti-inflammatory, analgesic and immunomodulatory models, confirming the antimicrobial and immunomodulatory activities. Phytochemistry was done in the crude drug and extracts. Quality control parameters are described (micrographic drawings and phytochemical characteristics). Evidence is presented that cultivated rhizome has antimicrobial and immunomodulatory activities, validating the popular use and helping the industrial development of phytopharmaceutical products.

The essential oils from two native species from Guatemala were studied for their chemical composition and the dichloromethane and methanol extracts for their biological activity. A GC-MS analysis of the essential oil from Piper jacquemontianum Kunth, Piperaceae, showed 34 constituents, consisting mainly of linalool (69.4%), while Piper variabile C. DC. essential oil had 36 constituents, camphor (28.4%), camphene (16.6%) and limonene (13.9%) being the major components. Dichloromethane extracts of both species were cytotoxic against MCF-7, H-460 and SF-268 cell lines (<7 µg/mL). Dichloromethane extract of P. jacquemontianum was slightly active against bacteria (0.5 mg/mL), was active against promastigotes of Leishmania (20.4-61.0 µg/mL), and epimastigotes of Trypanosoma cruzi (51.9 µg/mL). The methanol extract of P. variabile showed antimalarial activity against Plasmodium falciparum F32 (4.5 µg/mL), and the dichloromethane extract against Leishmania (55.8-76.3 µg/mL) and T. cruzi (45.8 µg/mL). None of the extracts from the two species was active against Aedes aegypti larvae and Artemia salina nauplii.

Três bioensaios de letalidade com o crustáceo de água salgada Artemia salina Leach, Artemiidae, (teste convencional em microplaca de 96 poós Artoxkit microbiotest M) e o crustáceo de água doce Thamnocephalus platyurus Packard, Thamnocephalidae (Thamnotoxkit microbiotest F), foram comparados utilizando extratos de dez espécies de plantas da Guatemala. Foi previamente observado que cinco delas possuem atividade anti-Artemia: Solanum americanum Mill., Solanaceae, Gliricidia sepium (Jacq.) Kunth ex Walp., Fabaceae, Neurolaena lobata (L.) Cass., Asteraceae, Petiveria alliacea L., Phytolaccaceae e Ocimum campechianum Mill., Lamiaceae. As outras cinco espécies, Curatella americana L., Dilleniaceae, Prunus barbata Koehne, Rosaceae, Quercus crispifolia Trel., Fagaceae, Rhizophora mangle L., Rhizophoraceae e Smilax domingensis Willd., Smilacaceae, não. Todas as plantas sem atividade anti-Artemia não tiveram nenhum efeito letal em ambos os ensaios com A. salina. Para as plantas com atividade anti-Artemia o M Artoxkit não foi sensível a G. sepium e teste convencional de Artemia não foi sensível a S. americanum, G. sepium e N. lobata. Todos os extratos vegetais, exceto o de C. americana, apresentaram um efeito letal sobre T. platyurus e a concentração letal média (CL50) para este organismo em todos os casos foram substancialmente inferiores aos da espécie de teste de água salgada. Este estudo revelou que T. platyurus é teste promissor para uma investigação aprofundada na seleção de extratos de plantas com potenciais propriedades medicinais.

Three lethality bioassays, using the salt-water crustacean Artemia salina Leach, Artemiidae, (conventional 96 microwell plate test and the Artoxkit M microbiotest) and the freshwater crustacean Thamnocephalus platyurus Packard, Thamnocephalidae, (Thamnotoxkit F microbiotest), were compared using extracts of ten Guatemalan plant species. It was previously observed that five of them have anti-Artemia activity. These were: Solanum americanum Mill., Solanaceae, Gliricidia sepium (Jacq.) Kunth ex Walp., Fabaceae, Neurolaena lobata (L.) Cass., Asteraceae, Petiveria alliacea L., Phytolaccaceae, and Ocimum campechianum Mill., Lamiaceae. The five others: Curatella americana L., Dilleniaceae, Prunus barbata Koehne, Rosaceae, Quercus crispifolia Trel., Fagaceae, Rhizophora mangle L., Rhizophoraceae, and Smilax domingensis Willd., Smilacaceae, do not. All plants without anti-Artemia activity had no lethal effects in both assays with A. salina. For the plants with anti-Artemia activity the Artoxkit M was not sensitive to G. sepium and the conventional Artemia test was not sensitive to S. americanum, G. sepium and N. lobata. All the plant extracts, except for that of C. americana, had lethal effects on T. platyurus and the lethal median concentration (LC50) levels for this organism were in all cases substantially lower than those of the salt-water test species. This study revealed that T. platyurus is a promising test species worth further in depth investigation for toxicity screening of plant extracts with potential medicinal properties.