Estudio comparativo de la actividad anti-fúngica de extractos secuenciales de Fuchsia lycioides contra Candida sp / comparative study of the antifungal activity of sequencial extracts of Fuchsia lycioides against Candida sp

The genus Fuchsia is generally used in herbal preparations to treat conditions caused by microorganisms. Based on the popular use of this type of plants, the objective of this study was to obtain sequential extracts of increasing polarity from the branches of Fuchsia lycioides by maceration at room temperature and by the Soxhlet method at 60ºC, to later evaluate the antifungal capacity of the extracts against different clinical isolates of the Candida genus. The ethyl acetate extract exhibited strong anti-fungal activity, selectively inhibiting C. albicans strains with MIC and CMF values of 10 and 15 µg/mL, respectively; comparable with the drug itraconazole®. The analysis of the extract by GC-MS showed a high concentration of terpenoids (mainly phytol) and phenylpropanoids (mainly cinnamic acid), possibly responsible for the antifungal activity of the ethyl acetate extract of F. lycioides.

El género Fuchsia se usa generalmente en preparaciones de hierbas para tratar afecciones provocadas por microorganismos. En base al uso popular de este tipo de plantas, el objetivo de este estudio fue obtener los extractos secuenciales de polaridad creciente de las ramas de Fuchsia lycioides por maceración a temperatura ambiente y por el método Soxhlet a 60ºC, para luego evaluar la capacidad antifúngica de los extractos frente a diferentes aislados clínicos del genero Candida. El extracto de acetato de etilo exhibió una fuerte actividad antifúngica inhibiendo en forma selectiva las cepas de C. albicans con valores de CMI y de CMF de 10 y 15 µg/mL, respectivamente; comparables con el fármaco itraconazol®. El análisis del extracto por CG-EM mostró una alta concentración de terpenoides (principalmente fitol) y fenilpropanoides (principalmente ácido cinámico), posibles responsables de la actividad antifúngica del extracto de acetato de etilo de F. lycioides.

Bioactivities of Flavonoids from Lopezia racemosa.

Lopezia racemosa Cav. (Onagraceae) has been used in Mexican traditional medicine to alleviate stomachache, biliary colic, urine retention, stomach cancer, and skin, dental, buccal, and urinary infections. The objective of this study was to determine the bioactivities of specific parts of the plant to scientifically confirm its traditional use. Aerial parts and flowers were macerated and subsequently extracted with hexane, chloroform, and methanol. This study was focused on the analysis of polar components, and thus the methanolic fractions were selected for further investigations. These fractions were evaluated for their antimicrobial activity using a panel of bacterial Gram-positive and -negative strains, as well as fungal strains, including filamentous fungi and yeasts. In addition, the cytotoxic activity of the extract was assessed by MTT using the human-derived monocytic THP-1 and the normal human fibroblast cell lines. Various fractions showed antimicrobial activity against various pathogens, although the most relevant were against Pseudomonas aeruginosa and Trichophyton mentagrophytes. No inhibition of yeasts was recorded. Only four fractions showed cytotoxic effects when the human-derived THP-1 and fibroblast cells were assessed. The four flavonoids isolated from the extract were luteolin, luteolin-6-C-hexoside, luteolin-8-C-hexoside, and hyperoside. The biological activities presented in this study validate some traditional uses of the plant.

A Cytotoxic and Anti-inflammatory Campesterol Derivative from Genetically Transformed Hairy Roots of Lopezia racemosa Cav. (Onagraceae).

The genetically transformed hairy root line LRT 7.31 obtained by infecting leaf explants of Lopezia racemosa Cav with the Agrobacterium rhizogenes strain ATCC15834/pTDT, was evaluated to identify the anti-inflammatory and cytotoxic compounds reported previously for the wild plant. After several subcultures of the LRT 7.31 line, the bio-guided fractionation of the dichloromethane-methanol (1:1) extract obtained from dry biomass afforded a fraction that showed important in vivo anti-inflammatory, and in vitro cytotoxic activities. Chemical separation of the active fraction allowed us to identify the triterpenes ursolic (1) and oleanolic (2) acids, and (23R)-2α,3ß,23,28-tetrahydroxy-14,15-dehydrocampesterol (3) as the anti-inflammatory principles of the active fraction. A new molecule 3 was characterized by spectroscopic analysis of its tetraacetate derivative 3a. This compound was not described in previous reports of callus cultures, in vitro germinated seedlings and wild plant extracts of whole L. racemosa plants. The anti-inflammatory and cytotoxic activities displayed by the fraction are associated to the presence of compounds 1-3. The present study reports the obtaining of the transformed hairy roots, the bioguided isolation of the new molecule 3, and its structure characterization.

Divergence times, historical biogeography, and shifts in speciation rates of Myrtales.

We examine the eudicot order Myrtales, a clade with strong Gondwanan representation for most of its families. Although previous phylogenetic studies greatly improved our understanding of intergeneric and interspecific relationships within the order, our understanding of inter-familial relationships still remains unresolved; hence, we also lack a robust time-calibrated chronogram to address hypotheses (e.g., biogeography and diversification rates) that have implicit time assumptions. Six loci (rbcL, ndhF, matK, matR, 18S, and 26S) were amplified and sequenced for 102 taxa across Myrtales for phylogenetic reconstruction and ten fossil priors were utilized to produce a chronogram in BEAST. Combretaceae is identified as the sister clade to all remaining families with moderate support, and within the latter clade, two strongly supported groups are seen: (1) Onagraceae+Lythraceae, and (2) Melastomataceae+the Crypteroniaceae, Alzateaceae, Penaeaceae clade along with Myrtaceae+Vochysiaceae. Divergence time estimates suggest Myrtales diverged from Geraniales ∼124Mya during the Aptian of the Early Cretaceous. The crown date for Myrtales is estimated at ∼116Mya (Albian-Aptian). BioGeoBEARS showed significant improvement in the likelihood score when the "jump dispersal" parameter was added. South America and/or Africa are implicated as important ancestral areas in all deeper nodes. BAMM analyses indicate that the best configuration included three significant shifts in diversification rates within Myrtales: near the crown of Melastomataceae (∼67-64Mya), along the stem of subfamily Myrtoideae (Myrtaceae; ∼75Mya), and along the stem of tribe Combreteae (Combretaceae; ∼50-45Mya). Issues with conducting diversification analyses more generally are examined in the context of scale, taxon sampling, and larger sets of phylogenetic trees.

Variation in pollen limitation and floral parasitism across a mating system transition in a Pacific coastal dune plant: evolutionary causes or ecological consequences?

BACKGROUND AND AIMS: Evolutionary transitions from outcrossing to self-fertilization are thought to occur because selfing provides reproductive assurance when pollinators or mates are scarce, but they could also occur via selection to reduce floral vulnerability to herbivores. This study investigated geographic covariation between floral morphology, fruit set, pollen limitation and florivory across the geographic range of Camissoniopsis cheiranthifolia, a Pacific coastal dune endemic that varies strikingly in flower size and mating system. METHODS: Fruit set was quantified in 75 populations, and in 41 of these floral herbivory by larvae of a specialized moth (Mompha sp.) that consumes anthers in developing buds was also quantified. Experimental pollen supplementation was performed to quantify pollen limitation in three large-flowered, outcrossing and two small-flowered, selfing populations. These parameters were also compared between large- and small-flowered phenotypes within three mixed populations. KEY RESULTS: Fruit set was much lower in large-flowered populations, and also much lower among large- than small-flowered plants within populations. Pollen supplementation increased per flower seed production in large-flowered but not small-flowered populations, but fruit set was not pollen limited. Hence inadequate pollination cannot account for the low fruit set of large-flowered plants. Floral herbivory was much more frequent in large-flowered populations and correlated negatively with fruit set. However, florivores did not preferentially attack large-flowered plants in three large-flowered populations or in two of three mixed populations. CONCLUSIONS: Selfing alleviated pollen limitation of seeds per fruit, but florivory better explains the marked variation in fruit set. Although florivory was more frequent in large-flowered populations, large-flowered individuals were not generally more vulnerable within populations. Rather than a causative selective factor, reduced florivory in small-flowered, selfing populations is probably an ecological consequence of mating system differentiation, with potentially significant effects on population demography and biotic interactions.

Insect herbivores associated with Ludwigia species, Oligospermum section, in their Argentine distribution.

The South American water primroses, Ludwigia grandiflora (Michx.) Greuter & Burdet, L. grandiflora subsp. hexapetala (Hook. & Arn.) G.L. Nesom & Kartesz, Ludwigia peploides (Kunth) P.H. Raven, and L. p. subsp. montevidensis (Spreng.) P.H. Raven (Onagraceae, Section Oligospermum), have become invasive in several watersheds of the United States and Europe. Surveys were carried out in center-east of Argentina to find insect species that might serve as biological control agents for L. g. subsp. hexapetala in California and elsewhere. Stems (0.5-0.6 m) of Ludwigia species, Sect. Oligospermum, were collected in 41 sites and analyzed in the laboratory; immature insects were reared to adults. The plant species found in the area were L. grandiflora (2 sites), L. g. subsp. hexapetala (33 sites), and L. p. subsp. montevidensis (4 sites). There was a variety of insect guilds feeding on L. g. subsp. hexapetala, including six species with stem-borer larvae, one species with fruit-feeding larvae, four species with defoliating larvae, two species with defoliating larvae on young leaves and axil meristems, one species of cell content feeder, and three species of sap feeders. Nine of these species also have defoliating adults. Biological information on most of them is provided. Of these insect herbivores, only two species were also found on L. grandiflora, and one on L. peploides. Several of the species found on L. g. hexapetala, such as the cell-content feeder Liothrips ludwigi (Thysanoptera), the stem-borers Merocnemus binotatus (Boheman) and Tyloderma spp. (Coleoptera), are promising candidates for biocontrol agents.

Production of the anti-inflammatory compound 6-O-palmitoyl-3-O-ß-D-glucopyranosylcampesterol by Callus cultures of Lopezia racemosa Cav. (Onagraceae).

Lopezia racemosa Cav. is a plant used in Mexican traditional medicine to heal inflammatory diseases. From this plant we isolated the novel compound 6-O-palmitoyl- 3-O-ß-D-glucopyranosylcampesterol (1) and 6-O-palmitoyl-3-O-ß-D-glucopyranosyl-ß-sitosterol (2), previously reported to have cytotoxic activity on several cancer cell lines. We evaluated the anti-inflammatory activity of 1 in vivo by mouse ear edema induced with 12-O-tetradecanoylphorbol-13-acetate (TPA) and 57.14% inhibition was observed. The aim of our study was to obtain callus cultures derived from this plant species with the ability to produce the compounds of interest. Callus cultures were initiated on MS basal medium amended with variable amounts of naphthaleneacetic acid (NAA), or 2,4-dichlorophenoxyacetic acid (2,4-D), combined or not with 6-benzylaminopurine (BAP). Ten treatments with these growth regulators were carried out, using in vitro germinated seedlings as source of three different explants: hypocotyl, stem node, and leaf. Highest yield of 1 was observed on callus derived from leaf explants growing in medium containing 1.0 mg/L 2,4-D and 0.5 mg/L BAP. Selected callus lines produced less 1 than wild plants but the in vitro cultured seedlings showed higher production. So we conclude that it could be attractive to further investigate their metabolic potential.

Mercury methylation and the microbial consortium in periphyton of tropical macrophytes: effect of different inhibitors.

Macrophyte-associated periphyton is known as a site of Hg accumulation and methylation in tropical environments. Sulfate-reducing bacteria (SRB) is found in periphyton and its role in Hg methylation is acknowledged. However, the contribution of other microorganisms to this process is largely unknown. We tested the effect of inhibitors for different microorganisms on methylmercury (MMHg) formation on distinct macrophyte species from lakes of the Bolivian Amazon basin and in Brazil. We also tested the effect of inhibitors on bacterial secondary activity at two lakes in Brazil. Samples were incubated on-site with (203)Hg and Me(203)Hg was extracted and measured by liquid scintillation. MMHg formation on macrophytes varied among species ranging from 0.2% to 36%. Treatments with specific inhibitors resulted in reduction of MMHg production on most sites and inhibitors. The most successful treatment was the co-inhibition of SRB and methanogens. The inhibitions of algae and fungi activity showed fewer effects on methylation rates at all sites analyzed. Bacterial secondary activity was slightly affected by algae and fungi inhibition, and largely influenced by prokaryotic, SRB and methanogens inhibition. The data suggest that MMHg formation may not be directly performed by all microorganisms in periphyton but depends on complex interactions among them.

Efecto Antibacteriano in vitro de Austroeupatorium inulaefolium H.B.K. (Salvia amarga) y Ludwigia polygonoides H.B.K. (Clavo de laguna) / In vitro antibacterial effect of Austroepatorium inulaefolium H.B.K. (salvia amarga) and Ludwigia polygonoides H.B.K. (clavo de laguna)

Los extractos alcohólicos de las hojas de Austroeupatorium inulaefolium H.B.K. y Ludwigia polygonoides H.B.K. se ensayaron in vitro para determinar la actividad antibacteriana y la CMI frente a Staphylococcus aureus, Escherichia coli y Pseudomonas aeruginosa. Ambos extractos presentaron actividad antibacteriana frente a Staphylococcus aureus; Austroeupatorium inulaefolium a concentraciones de 50mg/mL y Ludwigia polygonoides a 25mg/mL. Ninguno de los extractos mostró actividad frente a Escherichia coli o Pseudomonas aeruginosa.

The alcoholic extracts of the leaves of Austroeupatorium inulaefolium H.B.K. and Ludwigia polygonoides H.B.K. they were tested in vitro to determine the antibacterian activity and the CMI in response to Staphylococcus aureus, Escherichia coli and Pseudoma aeruginosa. Both extracts presented antibacterian activity in regards to Staphyloccus aureus, as well as to Austroeupatorium inulaefolium with 50 mg/ml concentrations and to Ludwigia polygonoides with 25 mg/ml. None of the extracts showed activity in response to Escherichia coli o Pseudomona aeruginosa.

Sulfate-reducing bacteria in floating macrophyte rhizospheres from an Amazonian floodplain lake in Bolivia and their association with Hg methylation.

Five subgroups of sulfate-reducing bacteria (SRB) were detected by PCR in three macrophyte rhizospheres (Polygonum densiflorum, Hymenachne donacifolia, and Ludwigia helminthorriza) and three subgroups in Eichhornia crassipes from La Granja, a floodplain lake from the upper Madeira basin. The SRB community varied according to the macrophyte species but with different degrees of association with their roots. The rhizosphere of the C4 plant Polygonum densiflorum had higher frequencies of SRB subgroups as well as higher mercury methylation potentials (27.5 to 36.1%) and carbon (16.06 +/- 5.40%), nitrogen (2.03 +/- 0.64%), Hg (94.50 +/- 6.86 ng Hg g(-1)), and methylmercury (8.25 +/- 1.45 ng Hg g(-1)) contents than the rhizosphere of the C3 plant Eichhornia crassipes. Mercury methylation in Polygonum densiflorum and Eichhornia crassipes was reduced when SRB metabolism was inhibited by sodium molybdate.

Interaction between visiting bees (Hymenoptera, Apoidea) and flowers of Ludwigia elegans (Camb.) hara (Onagraceae) during the year in two different areas in São Paulo, Brazil.

This study was designed to characterize the interactions between Ludwigia elegans flowers and visiting bees during two years in two areas 200 km apart, at the same latitude (approximately 22 masculine 48'S) but at different altitudes (Alumínio, 600 m, and Campos do Jordão, 1500 m), in the State of São Paulo, Brazil. As these flowers open simultaneously in the morning and lose their petals by sunset, interaction with bees occurs only during the photophase. Flowers of L. elegans were mainly visited by bees, the most frequent species being: Tetraglossula anthracina (Michener, 1989) (Colletidae), Rhophitulus sp. (Andrenidae), and Pseudagapostemon spp. (Halictidae), all considered specialized bees for collecting pollen and nectar from these flowers, as well as the generalist bee Apis mellifera Linnaeus, 1758 (Apidae). The specialist bees were temporally adjusted to the opening schedule of the flower, which occurs primarily in the morning, but shows a circannual variation. T. anthracina appears in both study areas, but only between December and April. The annual activity patterns of these specialist bees are synchronized to the phenology of L. elegans. Photoperiod and temperature cycles are suggested as the main synchronizers of both bees and plants.