The Genus Ageratina (Asteraceae) in America: An Insight into its Chemistry and Pharmacological Potential.

BACKGROUND: Ageratina is an American genus of the tribe Eupatorieae (Asteraceae), comprising about 320 species. In Mexico, some species of this genus are highly valued for their medicinal properties, particularly A. pichinchensis, A. petiolaris, and A. grandifolia. Furthermore, herbal preparations of A. pichinchensis are available for treating several mycoses. AIMS AND OBJECTIVE: The present review is aimed to summarize the chemical and pharmacological properties of 37 species of the Ageratina genus up to April, 2022. METHODS: Data were recorded using online scientific databases, including Scopus, PubMed, Google Scholar, Taylor and Francis Imprints, National Center for Biotechnology Information, Science Direct, JSTOR, and SciFinder. The information was gathered from research articles, relevant books on herbal medicinal plants and the history of medicinal plants from Mexico, theses, reports, and web pages. RESULTS: The specialized metabolites present in the Ageratina genus belong to different chemical classes, including flavonoids, benzyl benzoates, benzofurans, chromenes, and terpenoids. The chromenes, benzofurans, and benzyl benzoates are the metabolites most widespread in the genus. So far, the species more thoroughly investigated is A. adenophora. Ageratina has received little attention from the pharmacological point of view. The studies are limited to 10 species. Biological studies have been conducted on extracts and/or compounds isolated from plants collected mainly from China and Mexico. The results revealed that the extracts and metabolites possess several biological activities, including antiviral, antioxidant, antimicrobial, anti-inflammatory, antinociceptive, antifeedant, larvicidal, acaricidal, antidiabetic, antiprotozoal, and wound-healing properties. In the case of A. pichinchensis, A. petiolaris, and A. grandifolia, the pharmacological studies provided evidence for their use for treating gastrointestinal complaints and diabetes. Furthermore, herbal preparations of A. pichinchensis are now widely used for alleviating onychomycosis. A. adenophora, is the most investigated species, chemically and biologically; however, some hepatotoxicity effect has been recorded. CONCLUSION: This review recapitulates information on the Ageratina genus, highlighting the phytochemistry and biological activities of the species investigated. It is important to point out that the pharmacological potential of this large genus remains largely unexplored.

The global loss of floristic uniqueness.

Regional species assemblages have been shaped by colonization, speciation and extinction over millions of years. Humans have altered biogeography by introducing species to new ranges. However, an analysis of how strongly naturalized plant species (i.e. alien plants that have established self-sustaining populations) affect the taxonomic and phylogenetic uniqueness of regional floras globally is still missing. Here, we present such an analysis with data from native and naturalized alien floras in 658 regions around the world. We find strong taxonomic and phylogenetic floristic homogenization overall, and that the natural decline in floristic similarity with increasing geographic distance is weakened by naturalized species. Floristic homogenization increases with climatic similarity, which emphasizes the importance of climate matching in plant naturalization. Moreover, floristic homogenization is greater between regions with current or past administrative relationships, indicating that being part of the same country as well as historical colonial ties facilitate floristic exchange, most likely due to more intensive trade and transport between such regions. Our findings show that naturalization of alien plants threatens taxonomic and phylogenetic uniqueness of regional floras globally. Unless more effective biosecurity measures are implemented, it is likely that with ongoing globalization, even the most distant regions will lose their floristic uniqueness.

Biogeographic regionalization by spatial and environmental components: Numerical proposal.

Regionalization through the analysis of species groups offers important advantages in conservation biology, compared to the single taxon approach in areas of high species richness. We use a systematic framework for biogeographic regionalization at a regional scale based on species turnover and environmental drivers (climate variables and soil properties) mainly of herbaceous plant species richness. To identify phytogeographic regions in the Balsas Depression (BD), we use Asteraceae species, a family widely distributed in Seasonally Dry Tropical Forest (SDTF) and the most diverse of the vascular plants in Mexico. Occurrence records of 571 species were used to apply a quantitative analysis based on the species turnover, the rate of changes in their composition between sites (ß-Simpson index) and the analysis of the identified environmental drivers. Also, the environmental predictors that influence species richness in the SDTF were determined with a redundancy analysis. We identified and named two phytogeographic districts within the SDTF of the BD (Upper Balsas and Lower Balsas). According to the multi-response permutation procedure, floristic composition of the two districts differs significantly, and the richness of exclusive species in Upper Balsas was higher (292 species) than in the Lower Balsas (32 species). The proportion of Mg and Ca in the soil and the precipitation of the driest three-month period were the environmental factors with greatest positive influence on species richness. The division of geographic districts subordinated to the province level, based on diverse families such as Asteraceae, proved to be appropriate to set up strategies for the conservation of the regional flora, since at this scale, variation in species richness is more evident. Our findings are consistent with a growing body of biogeographic literature that indicates that the identification of smaller biotic districts is more efficient for the conservation of biodiversity, particularly of endemic or rare plants, whose distribution responds more to microhabitats variation.

Distribution, richness and conservation of the genus Salvia (Lamiaceae) in the State of Michoacán, Mexico.

Little attention has been paid in Mexico to species' geographical distribution, particularly documenting geographic ranges, as a tool to estimate their conservation status. The objective of this study was to review known species distribution and propose potential and conservation status for Salvia species in Michoacán sState using Ecological Niche Models (ENM). We reviewed taxonomic studies for Salvia in Michoacán to compile an initial species checklist, built upon with recently-described species; all the specimens deposited in the National Herbarium were reviewed. The collection data allowed us to build niche models of Salvia species reported for Michoacán. ENM were generated for the species listed using Maxent. In order to minimise collinearity, environmental variables were selected using a Pearson correlation test. Individual models were statistically evaluated and the potential distribution models for each individual species were stacked to obtain the map of richness potential distribution in the State. A total of 66 species of Salvia are listed for Michoacán; however, ENM could only be constructed for 42 of those with ≥ 5 specimens. The environmental variable that most strongly contributed to the models was annual average temperature. The models estimated that Salvia species occupy an area of 23,541 km2 in the State, 72% in the Trans-Mexican Volcanic Belt and a second richest ecoregion is the Sierra Madre del Sur. Although only 3% of the potential distribution area for Salvia in Michoacán is within Protected Areas (PAs), nonetheless, no PA includes rare species. It will therefore be necessary to consider new protection areas or expand existing ones in order to adequately conserve Salvia richness and rarity in the State.

Chemical Composition and Antimicrobial Activity of Ageratina deltoidea.

The chemical study of Ageratina deltoidea afforded grandiflorenic acid (1), ent-kaurenoic acid (2), and eight benzylbenzoates (3 - 10), two of them, 3,5-dimethoxybenzyl 2,3,6-trimethoxybenzoate (5) and 4-(ß-d-glucopyranosyloxy)-3-hydroxybenzyl 2,6-dimethoxybenzoate (9), described for the first time. In addition, the new sesquiterpene lactone deltoidin C (13), together with the known 11 and 12, the phenolic compounds: ayanin, 2,6-dimethoxybenzoic acid, methyl 3,4-dihydroxycinnamate, chlorogenic acid, and 3,5-dicaffeoylquinic acid were also isolated. The structures of these compounds were determined by spectroscopic methods and chemical reactions. The antibacterial and antifungal activities of compounds 1 - 12 were evaluated on Staphylococcus aureus, Escherichia coli, and Candida albicans. Deltoidin A (11) was the most active antibacterial agent (MIC 16.0 µg ml-1 ) against E. coli, and the ent-kaurenoid derivatives (1 - 2) showed activity (MIC 31.0 µg ml-1 ) against S. aureus.

Meso- or xeromorphic? Foliar characters of Asteraceae in a xeric scrub of Mexico.

BACKGROUND: The anatomical traits associated with water deficit are also observed in plants growing in poor soils. The species may resist water deficit through three main strategies: escape, avoid or tolerate. The Pedregal de San Ángel Ecological Reserve (REPSA), Mexico, is an environment with low nutrient soil and low water availability. It is set on the basalt formation derived from the Xitle volcano eruption. The main vegetation type is characterized as xerophytic shrub. Thus we expect that species growing in this community will show leaf xeromorphic traits and may have any of the three response strategies. We analyzed the foliar anatomy of 52 species of the Asteraceae family at the REPSA because it is the most abundant angiosperm family in the site, showing a wide variety of growth forms and anatomical variation. RESULTS: The foliar anatomies of the studied Asteraceae were highly variable as well as their quantitative traits as revealed by principal component analysis. This agrees with previous studies that found great anatomical variation within the family. Leaves have multiple layered palisade parenchyma and parenchyma bundle sheaths and could not be categorized as xeromorphic because they possess mesomorphic leaf features as simple lamina, single-layered epidermis, and soft large-size glabrous leaves with high specific leaf area. CONCLUSIONS: The combination of mesomorphic and few xeromorphic foliar traits with other characters at the genus and tribal level probably has been essential in Asteraceae to colonize various environments, including those with low water and nutrient availability.

Seco-eremophiladiolides and eremophilane glucosides from Pittocaulon velatum.

Two seco-eremophiladiolides, velatumolide and epi-velatumolide, the trihydroxyfuranoeremophilane velatumin, and three eremophilane glucosides were isolated from Pittocaulon velatum, together with several known compounds. The structures of these compounds were elucidated by spectroscopic analysis and chemical reactions. The anti-inflammatory activity of the isolated compounds was investigated using the TPA-induced ear edema model.

Chemical composition and biological activity of Laennecia schiedeana.

The chemical study of Laennecia schiedeana afforded three sterols, five diterpenes, five flavonoids, three caffeoyl derivatives of quinic acid, and two triterpenes. Evaluation of the cytotoxic activity of the extracts and isolated metabolites showed that 15-methoxy-16-oxo-15,16H-strictic acid was the most active compound [(15.05 +/- 2.2) microg/mL against U-251 cells]. In antibacterial assays the acetonic extract of leaves was the only active extract exhibiting its highest effect against the multiresistant Staphylococcus epidermidis (MIC 0.25 mg/mL). The anti-inflammatory activity observed was mild in the extracts and not relevant in the isolated compounds.

[Diversity of mineral inclusions in the subtribe Oncidiinae (Orchidaceae)]. / Diversidad de inclusiones minerales en la subtribu Oncidiinae (Orchidaceae).

Mineral inclusions in plants, of different chemical constitution and forms, have been studied in some plant groups and are currently used as diagnostic tools in taxonomic identifications. With the aim to identify their possible application in taxonomy, mineral inclusions in the leaves of 140 species of Oncidiinae (Orchidaceae) were analyzed and compared. Leave transversal sections were studied with the aid of clear field, phase contrast, and polarized light microscopy. Crystals commonly occured in mesophyll cells, and only in two species those were observed in epidermal cells. Several forms of calcium oxalate crystals and silicdioxide deposits in the form of stegmata were found. The most common crystalline forms were raphides, prisms and druses. Nevertheless, crystals like sands, and concentric and radial plates were also observed in few species. These crystalline forms of concentric and radial plates are reported for the first time in Oncidiinae and Orchidaceae. The stegmata are conical with rough surface, forming tiers along with fibers. Stegmata commonly occur in the vascular bundle sheath and in the abaxial or adaxial fiber bundles. However, few species do not have stegmata in fiber bundles and other species lack both. The taxonomic importance of these mineral inclusions is discussed for the different clades, genera or species within the subtribe Oncidiinae.

Diversidad de inclusiones minerales en la subtribu Oncidiinae (Orchidaceae)

Diversity of mineral inclusions in the subtribe Oncidiinae (Orchidaceae). Mineral inclusions in plants, of different chemical constitution and forms, have been studied in some plant groups and are currently used as diagnostic tools in taxonomic identifications. With the aim to identify their possible application in taxonomy, mineral inclusions in the leaves of 140 species of Oncidiinae (Orchidaceae) were analyzed and compared. Leave transversal sections were studied with the aid of clear field, phase contrast, and polarized light microscopy. Crystals commonly occured in mesophyll cells, and only in two species those were observed in epidermal cells. Several forms of calcium oxalate crystals and silicdioxide deposits in the form of stegmata were found. The most common crystalline forms were raphides, prisms and druses. Nevertheless, crystals like sands, and concentric and radial plates were also observed in few species. These crystalline forms of concentric and radial plates are reported for the first time in Oncidiinae and Orchidaceae. The stegmata are conical with rough surface, forming tiers along with fibers. Stegmata commonly occur in the vascular bundle sheath and in the abaxial or adaxial fiber bundles. However, few species do not have stegmata in fiber bundles and other species lack both. The taxonomic importance of these mineral inclusions is discussed for the different clades, genera or species within the subtribe Oncidiinae. Rev. Biol. Trop. 58 (2): 733-755. Epub 2010 June 02.

Las inclusiones minerales en las plantas, han sido utilizadas como herramientas de diagnóstico en la identificación taxonómica. Se analizaron y compararon las inclusiones minerales en las hojas de 140 especies de Oncidiinae (Epidendroideae: Orchidaceae). Las secciones transversales de hojas se observaron para describir las inclusiones minerales con el apoyo de la microscopía de luz en campo claro, contraste de fases y polarización. Los cristales generalmente están presentes en las células del mesófilo, y sólo dos especies los presentan en las células epidérmicas. Se encontraron cristales de oxalato de calcio de diferentes formas y depósitos de dióxido de sílice en forma de estégmatos. Las formas cristalinas más comunes son rafidios, prismas y drusas. Sin embargo, algunas especies tienen cristales en arena, concéntricos o en placas radiales. En esta investigación se reportan las dos últimas por primera vez para Oncidiinae y también para Orchidaceae. Los estégmatos son cónicos con superficie rugosa, generalmente formando hileras a lo largo de las fibras. Comúnmente se presentan en los haces vasculares y en los haces de fibras abaxiales. Sin embargo, existen especies cuyos haces de fibras no tienen estégmatos, así como especies sin haces de fibras ni estégmatos. Se discute la importancia taxonómica de estas inclusiones minerales para los diferentes clados, géneros y/o especies de Oncidiinae.

Quaternary range dynamics and polyploid evolution in an arid brushland plant species (Melampodium cinereum, Asteraceae).

Pleistocene climatic fluctuations played a principal role for range formation and population history of many biota, including regions not directly affected by glaciations, such as the arid habitats of the southwestern United States and adjacent Mexico. Specifically, drought-adapted species are expected to have persisted during cooler and wetter periods in one or more refugia, resulting in lineage differentiation, from where they reached their current distribution after range expansion in the course of Holocene aridification. Here, we test this hypothesis using Melampodium cinereum (Asteraceae), a morphologically and cytologically variable species of dry brushlands of Texas and adjacent Mexico. In line with the hypothesized presence of several refugia, AFLP data provide strong evidence for the presence of geographically distinct genetic lineages, which, however, only partly agree with current intraspecific taxonomy. Despite multiple origins, tetraploids form a genetically cohesive group. The exclusive occurrence of tetraploids in a range parapatric to that of the diploids likely results from former geographic isolation of cytotypes, lending further support for the presence of Pleistocene refugia. Whereas plastid sequence data show a clear signal for the expected Holocene range and population expansion, they show little geographic structure and high levels of intrapopulational diversity. This may be due to lineage sorting during periods of population separation and/or substantial gene flow among populations via seeds, which has not been sufficient to erode the overall pattern of genetic divergence resulting from geographic isolation.

Molecular phylogenetic analyses of nuclear and plastid DNA sequences support dysploid and polyploid chromosome number changes and reticulate evolution in the diversification of Melampodium (Millerieae, Asteraceae).

Chromosome evolution (including polyploidy, dysploidy, and structural changes) as well as hybridization and introgression are recognized as important aspects in plant speciation. A suitable group for investigating the evolutionary role of chromosome number changes and reticulation is the medium-sized genus Melampodium (Millerieae, Asteraceae), which contains several chromosome base numbers (x=9, 10, 11, 12, 14) and a number of polyploid species, including putative allopolyploids. A molecular phylogenetic analysis employing both nuclear (ITS) and plastid (matK) DNA sequences, and including all species of the genus, suggests that chromosome base numbers are predictive of evolutionary lineages within Melampodium. Dysploidy, therefore, has clearly been important during evolution of the group. Reticulate evolution is evident with allopolyploids, which prevail over autopolyploids and several of which are confirmed here for the first time, and also (but less often) on the diploid level. Within sect. Melampodium, the complex pattern of bifurcating phylogenetic structure among diploid taxa overlain by reticulate relationships from allopolyploids has non-trivial implications for intrasectional classification.

Chemical constituents of Roldana lineolata.

The new eremophilanolide 1, the known eremophilane derivatives 2 and 3, already described as part of mixtures, the known compounds hyperin, 2''-acetylhyperin and two calenduladiol esters were isolated from Roldana lineolata. Their structures were determined by spectroscopic methods. Compounds 1 and 2 as well as their acetylated and oxidized derivatives were tested against several fungi strains. Eremophilanolide 1 showed a mild activity against Trichophyton mentagrophytes.

Cacalol derivatives from Roldana angulifolia.

Four new modified eremophilanes, angulifolide (1) and angulifolins A-C (2-4), and two new triacetylglucosides (7 and 8) were isolated from Roldana angulifolia, together with several known compounds. The structures of the new compounds were elucidated by spectroscopic analysis and chemical reactions. The absolute configuration of compounds 2 and 3 was established by Mosher ester methodology. Cytotoxicity against selected human cancer cell lines was determined for the more abundant isolated metabolites.

Eremophilanes from Senecio mairetianus and some reaction products.

Eight new eremophilanolides (1, 2, 4-7, 9, and 10), a new eremophilane (13), and several known compounds were isolated from the roots and aerial parts of Senecio mairetianus. The chemical structures were proposed taking into consideration spectroscopic analyses and chemical transformations. X-ray diffraction analysis of 2, 4, and 9 confirmed their structures. The stereochemistry of 1,10-epoxy-8alpha-methoxyermophilanolide (3) was determined. Compounds 4-7, 9, and 10 are possible artifacts obtained by preparation of the alkaloidal extract.

Identifying priority areas for conservation in mexican tropical deciduous forest based on tree species

El objetivo principal del trabajo fue identificar y jerarquizar áreas prioritarias para la conservación de los árboles que se distribuyen de manera exclusiva o casi exclusivamente en el bosque tropical caducifolio en México, un tipo de vegetación seriamente amenazado a nivel mundial. La información se obtuvo a través de la consulta de literatura florística especializada, con la que se generó una lista de 425 especies arbóreas (67,5 por ciento endémicas de México), con 56 familias y 185 géneros registrados a nivel de estado. El grado de conservación de las especies se evaluó registrando su presencia en las Áreas Naturales Protegidas de México que incluyen dentro de sus límites porciones con bosque tropical caducifolio. Por análisis de parsimonia se determinaron 16 áreas de endemismo, sustentadas por 54 sinapomorfias y 73 autapomorfias (72,4 por ciento endémicas de México). Las áreas protegidas incluyen una baja a mediana proporción de las especies arbóreas de amplia distribución (129 especies, 30,3 por ciento) y de aquellas que caracterizan las áreas de endemismo (56 de 127 especies, 44,1 por ciento). En este último grupo, solo 7 especies están incluidas en una categoria de riesgo. El análisis de complementaridad (basado en la riqueza de especies y de aquellas localizadas en áreas de endemismo) y de diversidad filogenética (número de familias y géneros encontrados en cada estado) coinciden en asignar como áreas prioritarias para la conservación a los estados de Chiapas, Guerrero, Jalisco, Michoacán, Oaxaca y Yucatán. Con base en los resultados se proponen recomendaciones para el desarrollo de estrategias para asegurar la conservación de los árboles del bosque tropical caducifolio mexicano

Toward the identification of a core zone in the Tehuacán-Cuicatlán biosphere reserve Mexico based on parsimony analysis of endemicity of flowering plant species

La evaluación de los patrones de distribución de 174 especies de plantas con flores endémicas de la Reserva de la Biosfera Tehuacán - Cuicatlán, México, utilizando el Análisis de Parsimonia de Endemicidad (PAE), permite la identificación de ocho áreas de endemismo. Esas áreas de endemismo pueden considerarse irremplazables ya que sus especies no están presentes en ningún otro sitio. Las áreas de endemismo identificadas son propuestas como zonas núcleo de la Reserva de la Biosfera pues en ellas se podría conservar el 85 por ciento del endemismo y el 68 por ciento de la riqueza florística total registrada en la zona

Evaluation of the anti-inflammatory and antioxidant activities of the plastoquinone derivatives isolated from Roldana barba-johannis.

A phytochemical study of Roldana barba-johannis afforded two triterpenic esters, an eremophilanolide and three compounds structurally related to the antioxidants vitamin E and plastoquinone. Evaluation of the anti-inflammatory and antioxidant activities of sargahydroquinoic acid, sargachromenol, their mixture, and their methyl esters showed that most of them are antioxidant and anti-inflammatory agents.

Actitud del médico particular hacia el adiestramiento en la aplicación del dispositivo intrauterino. Delegación Jalisco del instituto Mexicano del Seguro Social, Septiembre de 1986 / Attitude of the family physician towards training in the application of the IUD, State of Jalisco of the Instituto Mexicano del Seguro Social, September, 1986

El propósito de este trabajo fue medir la disposición del Médico Familiar para el adiestramiento en la aplicación del Dispositivo Intrauterino (DIU). Para esta medición se empleó el critério psicosocial de "Disonancia Cognoscitiva", bajo dos puntos de vista: laboral y profesional. Se aplicó una encuesta de actitudes a siete unidades de medicina familiar, con un total de 213 médicos. El 51% manifestaron mucho o regular deseo de adiestrarse, el 61,5% consideran satisfecha la demanda en la aplicación del DIU y el 49.2% proponen que sea un médico especialista el que debe aplicarlo. La puntuación de disonancia cognoscitiva (PDC), permitió comparar la disposición y la no disposición, mayor FCD (p=.001). Asi mismo el 51% delos médicos familiares que dicen dominar el procedimiento son los que al mismo tiempo lo desan y el 48.4% lo desan sin dominarlo (PDC:p=.001)