Buddleja Cordata Research Articles

Host-plant sex and phenology of Buddleja cordata Kunth interact to influence arthropod communities.

Intraspecific variation in plants is expected to have profound impacts on the arthropod communities associated with them. Because sexual dimorphism in plants is expected to provide consistent variation among individuals of the same species, researchers have often studied the effect it has on associated arthropods. Nevertheless, most studies have focused on the effect of sexual dimorphism in a single or a few herbivores, thus overlooking the potential effects on the whole arthropod community. Our main objective was to evaluate effects of Buddleja cordata's plant-sex on its associated arthropod community. We surveyed 13 pairs of male and female plants every 2 months during a year (June 2010 to April 2011). Every sampling date, we measured plant traits (water content and leaf thickness), herbivory, and the arthropod community. We did not find differences in herbivory between plant sex or through time. However, we found differences in water content through time, with leaf water-content matching the environmental seasonality. For arthropod richness, we found 68 morphospecies associated with female and 72 with male plants, from which 53 were shared by both sexes. We did not observe differences in morphospecies richness; however, we found sex-associated differences in the diversity of all species and differences on the diversity of the most abundant species with an interesting temporal component. During peak flowering season, male plants showed higher values on both parameters, but during the peak fructification season female plants showed the higher values on both diversity parameters. Our research exemplifies the interaction between plant-phenology and plant-sex as drivers of arthropod communities' diversity, even when plant sexual-dimorphism is inconspicuous, and highlighting the importance of accounting for seasonal variation. We stress the need of conducting more studies that test this time-dependent framework in other dioecious systems, as it has the potential to reconcile previous contrasting observations reported in the literature.

Changes in Growth and Heavy Metal and Phenolic Compound Accumulation in Buddleja cordata Cell Suspension Culture under Cu, Fe, Mn, and Zn Enrichment.

Buddleja cordata cell suspension cultures could be used as a tool for investigating the capabilities of this species to tolerate heavy metals (HMs) and for assessing the effects of HMs on the accumulation of phenolic compounds in this species. It grows in a wide range of habitats in Mexico, including ultramafic soils, and mobilizes some HMs in the soil. The mobilization of these HMs has been associated with phenolic substances. In addition, this species is used in Mexican traditional medicine. In the present study, a B. cordata cell suspension culture was grown for 18 days in a culture medium enriched with Cu (0.03-0.25 mM), Fe (0.25-1.5 mM), Mn (0.5-3.0 mM), or Zn (0.5-2.0 mM) to determine the effects of these HMs on growth and HM accumulation. We also assessed the effects of the HMs on phenolic compound accumulation after 1 and 18 days of HM exposure. Cells were able to grow at almost all tested HM concentrations and accumulated significant amounts of each HM. The highest accumulation levels were as follows: 1160 mg Cu kg-1, 6845 mg Fe kg-1, 3770 mg Mn kg-1, and 6581 mg Zn kg-1. Phenolic compound accumulation was affected by the HM exposure time and corresponded to each HM and its concentration. Future research should analyze whole plants to determine the capabilities of Buddleja cordata to accumulate abnormally high amounts of HM and to evaluate the physiological impact of changes in the accumulation of phenolic compounds.

Predicting dynamic trajectories of a protected plant community under contrasting conservation regimes: Insights from data-based modelling

Data-based modelling of the dynamic behaviour of ecological communities is a big challenge in systems ecology and conservation biology. Implementing such models to forecast future scenarios is key for supporting decision-making in ecological reserves, given the multiple disturbances threatening their future. Using demographic and dynamic data for three tree (or tree-like) species from the Pedregal de San Ángel Ecological Reserve (Mexico City, Mexico), we constructed a family of dynamical models (using systems of ordinary differential equations) to reconstruct their dynamic interactions. The first two models considered two native species (Pittocaulon praecox and Buddleja cordata), with either antagonistic or cooperative interactions between them. These species have been considered ecosystem engineers playing different roles in the system and determining several community attributes. These models predict the transition from a stable steady state dominated by P. praecox (as reported in the 1950s) to the current community whose structure is apparently shifting to an alternative stable state dominated by B. cordata. The second pair of models additionally incorporate the invasive tree Eucalyptus camaldulensis, which exerts negative effects on all native plant species. The prediction of these models is an E. camaldulensis-dominated state with the exclusion of the native species from the reserve, provided this invasive species follows current population growth trends, without external intervention to check this process. Bifurcation analysis of this latter model allowed us to rationally design optimal intervention strategies that could potentially divert the trajectory from converging to an E. camaldulensis-only configuration into the stable coexistence of the native species. For the two-species and three-species models we made two versions, one with only competitive interactions and another one including a facilitation interaction between B. cordata and P. praecox. This analysis shows that facilitation is a requirement to achieve stable coexistence between the two native species, even in the presence of E. camaldulensis. The models constructed here, which integrate multiple data sources, help clarify conflicting empirical information regarding potential ecological mechanisms, and allow making predictions for strengthening the future management and E. camaldulensis control programs before its effects irreversibly modify the functioning and biodiversity of the biotic community protected in the reserve.

(Re)Designing Urban Parks to Maximize Urban Heat Island Mitigation by Natural Means

Urban trees play a key role in mitigating urban heat by cooling the local environment. However, the cooling benefit that trees can provide is influenced by differences in species traits and site-specific environmental conditions. Fifteen dominant urban tree species in parks from Mexico City were selected considering physiological traits (i.e., transpiration and stomatal conductance) and aesthetic and morphological characteristics. Species’ physiological performance was measured to explore the potential of trees to reduce urban heat load. Data were collected over a 4-week period in the months of April and May 2020, the warmest and driest months of the year in Mexico City. We used the Thermal UrbaN Environment Energy (TUNEE) balance model to calculate the cooling benefit of each species and the number of individuals necessary to reduce local air temperature. The highest midday transpiration was registered for Liquidambar styraciflua L. (0.0357 g m−2 s−1) and the lowest for Buddleja cordata H.B.K (0.0089 g m−2 s−1), representing an energy consumption and cooling potential of 87.13 and 21.69 J m−2 s−1, respectively. Similarly, the highest stomatal conductance was recorded for L. styraciflua., whereas the lowest was recorded for B. cordata. Based on the species transpiration rates and aesthetic characteristics, we developed a proposal and outline for a 50 × 50 m urban park (i.e., park community) consisting of six species with 19 individuals, and according to the TUNEE model, the proposed arrangement can reduce air temperature up to 5.3 °C. Our results can help urban planners to (re)design urban parks to mitigate urban heat while increasing urban tree diversity in parks.

Structural and ultrastructural injuries in leaves of Baccharis conferta and Buddleja cordata broad-leaved species of a forest impacted with ozone

The present study showed evidence of ozone damage to the structure of leaves of Baccharis conferta HBK and Buddleja cordata HBK broad-leaved species of the southwest of the Valley of Mexico using light, transmission, and scanning electron microscopy. These species are growing in the forests of Mexico City Metropolitan Area, one of the most polluted regions in the world for ozone. Ozone in the plants causes damage to the leaves and intensifies the decline of the forest at high altitudes such as the mountains where Desierto de los Leones, a National Park (DLNP), as treatment, compared with the forest of Miguel Hidalgo National Park (NINR), as control, exposed to low levels of air pollution. The most notorious damages were in the mesophyll, vascular bundle, and epidermis of the species studied in DLNP. Also the ultrastructure showed gradual injuries at the cellular level, initially higher in the vacuoles and chloroplasts and smaller in cytoplasm and mitochondria. NINR studies showed no evidence of damage in either of the two selected species or in the different microscopic techniques, which are related to measurements of low levels of air pollution.

Ecophysiological Vulnerability to Climate Change in Mexico City’s Urban Forest

Urban forests play an important role in regulating urban climate while providing multiple environmental services. These forests, however, are threatened by changes in climate, as plants are exposed not only to global climate change but also to urban climate, having an impact on physiological functions. Here, we selected two physiological variables (stomatal conductance and leaf water potential) and four environmental variables (air temperature, photosynthetically active radiation, vapor pressure deficit, and water availability) to compare and evaluate the ecophysiological vulnerability to climate change of 15 dominant tree species from Mexico City’s urban forest. The stomatal conductance response was evaluated using the boundary-line analysis, which allowed us to compare the stomatal response to changes in the environment among species. Our results showed differential species responses to the environmental variables and identified Buddleja cordata and Populus deltoides as the least and most vulnerable species, respectively. Air temperatures above 33°C and vapor pressure deficit above 3.5 kPa limited the stomatal function of all species. Stomatal conductance was more sensitive to changes in leaf water potential, followed by vapor pressure deficit, indicating that water is a key factor for tree species performance in Mexico City’s urban forest. Our findings can help to optimize species selection considering future climate change by identifying vulnerable and resilient species.

Biotechnological processes to obtain bioactive secondary metabolites from some Mexican medicinal plants.

The consumption of medicinal plants has increased in recent decades due to the fact that they biosynthesize compounds with many biological activities; thus, some plant species with biological potential are being utilized as raw material by the industries for preparation of drugs, phytodrugs, or food supplements. This has the consequence of overexploitation and deforestation, which endangers plant species-of-interest. In recent years, alternatives have been sought to eradicate this problem. A solution that was given and is maintained is plant biotechnology, which favors the production of secondary metabolites (SMt) with important biological activity. Plant biotechnology allows us to increase the yield of a compound-of-interest, reduces its production times and costs, and allows constant and controlled production of the raw material, while aiding in the protection of medicinal plants that are found in danger of extinction. In the scientific literature, procuring the SMt by means of biotechnological processes is described, highlighting the study of five species from Mexican traditional medicine (Lopezia racemosa, Galphimia glauca, Cnidoscolus chayamansa, and Buddleja cordata), and the main biological activities are as follows: anti-inflammatory, hepatoprotector, neuroprotector, anxiolytic, antitumoral, antibacterial, and antioxidant, among others. KEY POINTS: • Secondary metabolites produce by biotechnology processes • Active secondary metabolites isolated from Mexican medicinal plants • Recent advances on the production of some bioactive secondary metabolites.

Verbascoside-enriched fraction from Buddleja cordata Kunth ameliorates the effects of diabetic embryopathy in an animal model.

The deleterious effects of diabetes mellitus (DM) over development are apparently due to an increase in oxidative stress. Some antioxidants could prevent developmental alterations produced by diabetic state. Extracts of plants of the genus Buddleja are used traditionally for Mexican indigens to ameliorate some diseases. The purpose of this work was to evaluate the effect of the extract of Buddleja cordata over diabetic embryopathy. Two experimental approaches were used: an in vivo study and an in vitro model. In the first, rats were treated with streptozotocin, streptozotocin plus methanolic extract of B. cordata, or none. Females were sacrificed at gestational day (GD) 19, and biochemical clinical parameters were measured; also, the fetuses were obtained and morphologically analyzed. In the in vitro model, a verbascoside-enriched fraction (VEF) of the extract was used in whole embryo culture in order to search for the mechanisms for embryoprotection effect over hyperglycemia-induced malformations. In the in vivo experiments, B. cordata extract reduces the frequency and severity of fetal malformations produced by chemically induced diabetes, and additionally partially ameliorates the diabetic condition; in the in vitro model, both severity and frequency of embryo dysmorphogenesis were reduced by the VEF; also, this fraction reduces lipoperoxidation without affecting the activity of the antioxidant enzymes. The results suggest that verbascoside of methanolic extract and enriched fraction can directly affect the redox state, and thus, prevents the embryotoxicity mediated by oxidative stress, in embryos of diabetic pregnancy.

Antidepressant effect of buddleja cordata methanolic extract in chronic stress mouse model

Background: Preclinical studies in animal models have shown anti-inflammatory, analgesic, antioxidant, and neuroprotective effects of B. cordata. Objectives: To explore the antidepressant effect of a methanolic extract of Buddleja cordata leaves (MEBc) in early maternal separation and chronic restraint stress mouse model. Materials and Methods: From day 2 to day 21, the litters were removed from the maternal cage for 3h/day. Based on the pharmacological treatments, four experimental groups were established: sham animals without maternal separation, chronic restrained stress and oral administration (S group) or 10 ml/Kg/day saline solution (SS group) or 100 mg/kg/day of MEBc (MEBc group) or 20 mg/kg/day of fluoxetine (F group). After 4 weeks of these treatments the antidepressant activity was evaluated through behavioral tests and also IL-6 determinations were performed. Results: Mice administered with MEBc showed significantly diminished immobility time in the forced swimming test (P < 0.01), tail suspension test (P < 0.001) and the time spent in the open arm of the elevated plus-maze (P < 0.01) versus SS group. By contrast, animals treated with fluoxetine only diminished immobility time in the tail suspension test (P < 0.01). The vegetal extract was more effective (P < 0.05) that fluoxetine in preventing the increase of interleukin 6 (IL-6) over the hippocampus and prefrontal cortex region (45 and 20 %, respectively). Conclusion: These results demonstrate the antidepressant and anxiolytic effects of MEBc over the chronic stress depression-induced model.

The analytic hierarchy process for selection of suitable trees for Mexico City

Urban foresters require methodologies that help to select tree species for urban environments, mainly in places where there is a large number of potential species such as the Valley of Mexico. We applied the Analytic Hierarchy Process (AHP) to select suitable native tree species that are under-represented or non-existent in Mexico City trees. Through bibliographic research, the selection criteria and the list of trees to be evaluated were selected; later, a group of specialists in urban forestry and arboriculture determined by pair-wise comparison matrices the specific weight of each selection criterion, while a set of taxonomists evaluated the rating of each attribute for each species. Finally, for practical purposes, the synthesis of both evaluations resulted in a ranking of 15 tree species according to their degree of aptitude suggested for Mexico City. According to results, Buddleja cordata, Quercus glaucoides and Litsea glaucescens obtained the highest degree of suitability as a large, medium and small-size species, respectively. The AHP proved to be an appropriate methodology to solve a complex problem through multiple criteria evaluation by diverse specialists in the subject. The implementation of the results contributes to the selection process of suitable tree species for urban environments.

Effects of phenylalanine and methyl jasmonate on verbascoside production in Buddleja cordata Kunth cell suspension cultures

Buddleja cordata Kunth (Scrophulariaceae) is an important medicinal herb widespread in Mexico that produces diverse phenolic compounds; among others, the pharmacologically important phenylethanoid glycoside (PeG) verbascoside (VB, also named acteoside). This work describes the effects of the metabolic precursor, L-phenylalanine (L-Phe), and the elicitor, methyl jasmonate (MeJa), on biomass accumulation and VB production in a B. cordata cell-line under suspension culture conditions. Cultures were exogenously fed with different concentrations of the precursor and elicitor at the early and late stages of the exponential growth phase. Precursor or elicitor addition was most effective when added in the late-exponential phase. Cultures fed with 600 µM L-Phe reached the highest production of VB after a 10-day exposure time (1.96 g L−1, which was 130% higher than in control cultures). Maximum VB production after elicitation (4.8 g L−1, with an overall increase of 213% above control level) occurred with 50 µM MeJa after an exposure time of 48 h. VB production yields reported in this work exceed those of previously reported biotechnological efforts using cell suspension cultures and other in vitro systems to increase phenylethanoid glycosides production, especially, VB.

Effects of plant sex on insect abundance across three trophic levels in the perennial shrub Buddleja cordata

AbstractAlthough there is a growing interest in the effects of intra‐specific plant genetic variation on species interactions, the effects of plant sex, an important axis of genetic variation, have been less studied. In addition, previous work investigating plant sex effects on species interactions has frequently focused on bitrophic interactions (e.g., herbivory), usually ignoring plant sex effects on higher trophic levels (i.e., natural enemies). Here, we investigated the effects of plant sex on herbivore abundance and that of their natural enemies associated with the dioecious shrub Buddleja cordata Kunth (Scrophulariaceae). Furthermore, we measured a subset of plant traits frequently involved in herbivore resistance and the potentially underlying plant sex effects. To this end, we recorded the abundances of a specialist leaf‐chewing caterpillar [Acronyctodes mexicanaria Walker (Lepidoptera: Geometridae)] throughout an entire growing season. We also recorded information about the caterpillar’s parasitoids, as well as leaf water content, phenolic compounds, phosphorus, and nitrogen for male and female plants of B. cordata. Plant sex did not significantly influence caterpillar abundance but did have an effect on natural enemies, with parasitoid abundance being 2.4‐fold greater on female than on male plants. The effect of plant sex on parasitoids remained significant after accounting for caterpillar abundance, suggesting that it was underlain by a trait‐mediated (rather than density‐mediated) mechanism. Finally, we found that male plants had a higher concentration of phenolic compounds (other traits did not differ between plant sexes). These results provide valuable evidence for the extended effects of plant sex on the third trophic level and point at plant traits potentially mediating such effects.

Effect of stirring speed on the production of phenolic secondary metabolites and growth of Buddleja cordata cells cultured in mechanically agitated bioreactor

Shake-flask in vitro culture of Buddleja cordata cells produces large amounts of biomass and synthetizes verbascoside (VB), linarin and hydroxycinnamic acids, bioactive phenolic secondary metabolites (PSMs). In this work, we determined the effect of stirring speed on the growth of and production of PSMs [total phenolic, phenylethanoid glycoside and flavonoid contents (PeC, PeGC and FC, respectively)] by B. cordata cells cultured in two bioreactors. Two different stirring speeds (120 and 400 rpm) were tested in two stirred-tank bioreactors: a 2 L bioreactor equipped with a ring diffuser (B2RD) and a 3 L bioreactor with a sintered diffuser (B3SD). Growth kinetics of B. cordata cells were measured in the bioreactors and shake-flask systems. The stirring speed and type of bioreactor affected phases, parameters of growth and production of PSMs. The highest production of biomass (13.62 g L−1) and PSMs [PeC of 64.63 mg gallic acid equivalents g−1 (mg GAE g−1); PeGC of 119.24 mg VB equivalents g−1 (mg VBE g−1); and FC of 5.02 mg quercetin equivalents g−1 (mg QE g−1)] occurred in B2RD at 400 rpm. These values were similar to the found in shake-flasks system. This work establishes the basis for bioprocess advances of B. cordata focused on the development of a sustainable strategy for the management of natural resources and as a source of bioactive PSMs on a large scale.

In vivo anti-arthritic effect and repeated dose toxicity of standardized methanolic extracts of Buddleja cordata Kunth (Scrophulariaceae) wild plant leaves and cell culture

Ethnopharmacological relevanceBuddleja cordata Humb. Bonpl. & Kunth, known by the population as Tepozán blanco, is a shrub plant used in traditional herbal medicine in Mexico for the treatment of tumors, cancer, sores, skin burns, rheumatic pains and diseases related to inflammatory processes such as arthritis; authors adjudicate this etno-medicinal effect to the presence of secondary metabolites in the plant such as verbascoside, however due to its low concentration in recent years biotechnological tools are applied as cell culture to biosynthesize these pharmacological active metabolites in greater quantities.Aim of the study: Evaluate the possible toxic effect after a daily administration of MeOH extracts from wild plant leaves (Bc-Wp), and cell culture (Bc-Cc) of B. cordata for 28 days, and after their anti-edematous and antioxidant activities in vivo, as well their effect on the cytokines profile during experimental arthritis induced by complete Freund's adjuvant. Materials and methodsBoth extracts were evaluated in CD1 male mice first in a toxicity test of repeated dose administrations (1 g/kg) for 28 days, after which pharmacological activity of both extracts was measure during experimental induced arthritis where three doses were tested, at the end of the study edema formation, body weight gain and antioxidant activity were measure in edema and ganglionic tissues. Finally, dose that exerted the best protective effect (250 mg/kg) was evaluated to quantify its effect over ganglionic tissue concentration of lymphocytes T CD4+, and cytokines (IL-1β, TNF-α and IL-10), as well histological analysis in arthritic mice. ResultsBoth extracts (Bc-Wp and Bc-Cc) did not exert lethality, however body weight gain and food in-take were lower than in healthy mice administered with vehicles, also extract-treated animals showed a decrease in serum lipid concentration and only Bc-Wp extract treated animals decrease serum alkaline phosphatase after 28 daily administration compared to healthy un-treated mice. During experimental arthritis best inhibition effect over edema development was observed in those animals administered with both extracts at dose of 250 mg/kg (Bc-Wp and Bc-Cc) on day 28, compared to CFA un-treated mice. Also both extracts reduce oxidative damage over lipids and proteins at the same dose, in both ganglionic and edema tissue, as well antioxidant enzymatic response was reduced in both tissues compared to arthritic un-treated group. In ganglionic tissue of arthritic mice, CD4+ lymphocytes concentration was reduced by Bc-Wp and Bc-Cc treatment (250 mg/kg) respectively, as well IL-1β, and TNF-α levels. Only arthritic animals treated with Bc-Cc extract at 250 mg/kg generated a significant increase of IL-10 doubling the levels compared to CFA un-treated group. Histological analysis of popliteal ganglion showed that both extracts decrease the incidence of lytic lesions, lipid inclusions and leukocyte infiltration. ConclusionMethanolic extracts of wild Buddleja cordata and its cell cultures did not generated lethality after a daily administration for 28 days at 1 g/kg, but it was observed that both showed a lipid-lowering effect. Also at dose of 250 mg/kg both extracts exerted anti-edematous, protection against the oxidation of lipid and proteins, regulation on antioxidant enzymatic response, down-regulation on lymphocytes CD4+ producers of IL-1β and TNF-α, an increase in IL-10 levels, which caused a decrease in leukocyte infiltration in ganglionic tissue during experimental arthritis.

Mobilization and synthesis of seed storage and LEA proteins during natural priming of Buddleja cordata and Opuntia tomentosa

Background: In crop plants, the induction of seed storage protein mobilization and synthesis of LEA family proteins has been extensively described.Question: Natural priming promotes mobilization and synthesis of seed storage and LEA proteins in wild plants?Species studied: Buddleja cordata and Opuntia tomentosa. Study site: Reserva Ecológica del Pedregal de San Angel (REPSA).Methods: Natural priming treatments were applied to B. cordata and O. tomentosa seeds during one and six months respectively. Phosphorylated proteins fractions were obtained by affinity chromatography from control and treated seeds. Differences in protein pattern between control and treated seeds were determined by electrophoresis and the treated seed proteins were identified by LS/LS/MALDITOF. Results: The phosphorylated fraction of B. cordata treated seeds presented two proteins that were absent in the control protein fraction. These two proteins were identified as two different 11S globulins. The phosphorylated fraction of O. tomentosa treated seeds also presented two proteins that were absent in the control protein fraction. These two proteins were identified as a 12S globulin and a LEA protein.Conclusion: Seeds are subjected to changes in soil water content during their permanence in soil; this natural priming process promotes mobilization and synthesis of storage and LEA proteins that are involved in stress resistance.

ACTIVIDAD ANTI-INFLAMATORIA in vivo Y TOXICIDAD AGUDA DE EXTRACTOS METANÓLICOS DE HOJAS DE PLANTAS SILVESTRES Y CULTIVOS DE SUSPENSIONES CELULARES DE Buddleja cordata Kunth (Buddlejaceae)

Buddleja cordata is a species used by Mexican folk medicine for treating illnesses related to inflammation such as skin wounds and arthritis. It bio-synthesize metabolite such as verbascoside that contribute to its ethno-therapeutic properties as anti-inflammatory remedy. HPLC analysis showed that the methanolic extract from cell suspension cultures (Bc-Cc) and wild plant leaves (Bc-Wp) contained verbascoside, but concentration was higher in Bc-Cc (87.48 mg/g) than in wild plant (47.34 mg/g). In the acute toxicity model, none of the extracts generated any lethality or adverse effects. In acute inflammation model induced with TPA, Bc-Cc extract showed a greater edema inhibition at 2 mg/ear (61.72%), as well for carrageenan model at 200 mg/kg (48.87%). Bc-Wp showed lesser anti-inflammatory effect in both acute inflammation models than Bc-Cc. For Adjuvant-induced arthritis both extracts at 250 mg/kg generated a moderate inhibition over edema (≈33%) at day 28, and they were statistically no different to phenilbutazone. The culture in suspension of B. cordata obtained by biotechnological process contains greater amount of verbascosido and showed better anti-inflammatory activity; thus, representing a source for obtaining this type of secondary metabolite of pharmacological interest.

MICROPROPAGACI ́ON DEBuddleja cordataY EL CONTENIDO DEVERBASC ́OSIDO Y FENOLES TOTALES CON ACTIVIDAD ANTIOXIDANTE DELAS PL ́ANTULAS REGENERADAS

Buddleja cordata is a medicinal plant distributed in Mexican territory that is characterized for producing phenolic compounds possessing antioxidant activity. It was evaluated the type of morphogenetic responses induced by plant growth regulators. Furthermore, the content of verbascoside and total phenols was determined, as well as the antioxidant activity in regenerated plantlets. The greatest shoot proliferation (29.2 shoots per explant) was achieved in the stem-nodes that were grown in a half-strength Murashige and Skoog medium containing 4.44 M N6-benzyladenine. The greatest shoot heights of 4.3 and 4.7 cm (statistically not dierent) were obtained with gibberellic acid at 4.34 and 8.67 M, respectively. The highest percentage of rooting (89.4%) occurred with 2.45-M indole-3-butyric acid with 20.3 roots per shoot and an average root length of 4.4 cm. Of the rooted shoots, 91.7% were able to survive after 30 days of acclimatization. The verbascoside (1.0 mg g1) and total phenols (24.8 mg of gallic acid equivalents g1) content was related to antioxidant activity of the regenerated plantlets. The micropropagation of B. cordata might represent an alternative about massive production and depict the basis of the establishment of commercial crops and genetic studies.

Photoprotection of Buddleja cordata extract against UVB-induced skin damage in SKH-1 hairless mice.

BackgroundIn recent years, there has been considerable interest in using botanical agents to prevent skin damage resulting from solar UV-irradiation. Buddleja cordata is a plant that is known as “tepozan”. Some people in Mexico use the leaves of this plant to treat tumours, abscesses, sores and burns. The purpose of this study is to investigate the photoprotective properties of Buddleja cordata methanolic extract (BCME) against UVB-induced skin damage in SKH-1 hairless mice at the macroscopic and histological levels.MethodsBCME was characterised to determine its spectroscopic, chromatographic and antioxidant (DPPH, superoxide and hydroxyl radicals) properties. To conduct the photoprotection studies, BCME was applied topically to the skin of SKH-1 mice before acute exposure to UVB for 10 minutes. The murine skin samples were used for macroscopic and histological studies to assess tissue damage. Penetration of active components of BCME into stratum corneum on the dorsal area of mice was investigated in vivo by the tape stripping method. Moreover, genotoxicity of BCME was evaluated in a Vicia faba cell root micronucleus model.ResultsBCME displayed absorbance over the entire UVB spectrum, and its principal components included verbascoside and linarin. BCME exhibited antioxidant activity and significantly scavenged hydroxyl radicals. BCME reduced erythema, sunburn cell production, vessel congestion and epidermal thickening of UVB irradiated mouse skin. BCME penetrate the skin of mice. BCME did not exhibit genotoxic activity in the micronucleus test.ConclusionThe topical administration of BCME protected against acute UVB-induced damage in mouse SKH-1 skin, and our results suggest that BCME may potentially prevent photodamage.

Vegetation recovery and plant facilitation in a human-disturbed lava field in a megacity: searching tools for ecosystem restoration

Unplanned urban development threatens natural ecosystems. Assessing ecosystem recovery after anthropogenic disturbances and identifying plant species that may facilitate vegetation regeneration are critical for the conservation of biodiversity and ecosystem services in urban areas. At the periphery of Mexico City, illegal human settlements produced different levels of disturbance on natural plant communities developed on a lava field near the Ajusco mountain range. We assessed natural regeneration of plant communities 20 years after the abandonment of the settlements, in sites that received low (manual harvesting of non-timber forest products), medium (removal of aboveground vegetation), and high (removal of substrate and whole vegetation) disturbance levels. We also tested the potential facilitative role played by dominant tree and shrub species. Plant diversity and vegetation biomass decreased as disturbance level increased. Sites with high disturbance level showed poor regeneration and the lowest species similarity compared to the least disturbed sites. Six dominant species (i.e., those with the highest abundance, frequency, and/or basal area) were common to all sites. Among them, three species (the tree Buddleja cordata, and two shrubs, Ageratina glabrata and Sedum oxypetalum) were identified as potential facilitators of community regeneration, because plant density and species richness were significantly higher under their canopies than at open sites. We propose that analyzing community structural traits of the successional vegetation (such as species diversity and biomass) and identifying potential facilitator species are useful steps in assessing the recovery ability of plant communities to anthropogenic disturbances, and in designing restoration strategies.

Floral scents of typical Buddleja species with different pollination syndromes

Floral scents from Buddleja lindleyana, Buddleja loricata, Buddleja cordata and Buddleja tubiflora were evaluated using the dynamic headspace adsorption method and identified with coupled gas chromatography and mass spectrometry. In total, 13 compounds were identified from the flowers of B. cordata, 19 from B. lindleyana and 29 from B. loricata, representing 95.5%, 93.1% and 96.2% of the total floral scents in the three species, respectively. No floral scents were recorded from B. tubiflora. Main volatile compounds in B. cordata were trans-beta-ocimene (53.4%), lilac alcohol (9.6%) and lilac aldehyde (5.6%). Main volatile compounds in B. lindleyana were beta-caryophyllene (17.6%), alpha-farnesene (16.0%) and 3-octanone (9.8%). Main volatile compounds in B. loricata were 4-oxoisophorone (27.1%), alpha-farnesene (17.9%) and linalool (10.6%). The study suggested that the floral scents may have evolved in conjunction with the sensory capabilities of different visitors as a specific group of pollinators in representative Buddleja species. (C) 2012 Elsevier Ltd. All rights reserved.