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Globalization, the modern lifestyle, immuno-suppressive agents, invasive surgical procedures, the loss of efficacies of existing drugs, and multidrug resistance are some of the factors used to explain the rise in fungal infections in recent years. Significant advances have been made in attempts to replace existing antifungal schedules, especially with synthetic targets. The identification of other platforms for drug discovery is now entrenched in research programs across the globe. Plants offer significant benefits owing to their numerical superiority, exceedingly broad chemical basis and appealing sustainability characteristics. Furthermore, plants have a long and rich historical association with traditional approaches towards fungal diseases. These have in numerous instances served as markers in the bioassay-guided identification of the active constituents. Although the plant family Amaryllidaceae is conventionally associated with cancer and motor-neuron disease chemotherapies, around 30 of its species have been examined for antifungal activities with microgram per millilitre inhibitory activities detected in several instances. This review focuses on the nearly 40 constituents from the family, mainly isoquinoline alkaloids, which have been screened against around 50 fungal pathogens. Encouragingly, microgram per millilitre growth inhibitory activities were applicable for several of the compounds with a minimum inhibitory concentration of 4 μg/ml seen to be the lowest.

Question To what extent are species, including native and non-native species, influencing one another's distribution and abundance in the herb layer of a Minnesota oak woodland? Location Oak woodland succeeding into a more mesic forest, on bluffland of the Mississippi River, east-central Minnesota. Methods We collected plant composition and species cover data in 182 1.0 × 0.5 m quadrats regularly spaced on a 6-ha study grid in the oak woodland. We also recorded slope, slope position, aspect, elevation and photosynthetically active radiation (PAR) at each quadrat. Results Presence and abundance of other plant species, topographic variables and light availability explained only a small portion of the variation (5–19%) in the distribution and abundance of individual species. The most common strongest predictor of cover for the ten most common species was species richness, with the association being positive. The non-native species, garlic mustard (Alliaria petiolata) exhibited the strongest positive association with species richness. Only one of the 45 pair-wise comparisons of the ten species resulted in a negative relationship between the species. Abundance and distribution of two species were associated with topographic features, but this accounted for much less of the variation in abundance than did species richness. Conclusion We found little evidence that competition or any other interactions among common herb layer species, including the non-native Alliaria petiolata, play an important role in determining the abundance and the distribution of herb layer species in this oak woodland. Topographic factors may explain a small amount of the distribution and abundance patterns of a few species. But, for the most part, species are more likely to be present when other species are present, suggesting that they are simply establishing in microsites favourable to plants in general.

Representatives of the genus Cyrtanthus including Cyrtanthus contractus of the Amaryllidaceae family are widely used in African traditional medicine for the treatment of a range of ailments, including mental illness and age-related dementia. The alkaloid constituents distributed within the genus, which are chiefly responsible for the biological activity of the derived extracts, are thought to be influenced by changes in the growing environment. Natural growing populations of C. contractus were tagged and collected every 15th day of each month over a 12 month period. The ethanol bulb extracts from each of the collected samples were evaluated for total alkaloid content, cytotoxic effects, acetylcholinesterase and cyclooxygenase inhibition as well as antimicrobial activities. Some notable bioactivities were recorded for extracts collected during certain months of the year, particularly the cytotoxic effects against human cancer cell lines and enzyme inhibition (AChE and COX). The cytotoxic effects and AChE and COX enzyme inhibitory activities of extracts collected in May and September are of considerable interest. Similarly total alkaloids varied markedly from one month to the other. The bioactivity exhibited by C. contractus bulb extracts during certain months of the year, particularly in May and September, justifies the collection and use of these bulbs for treatment of the relevant ailments in traditional medicine during these periods.

There is a pressing need in antibiotic drug discovery for new drugs to counterbalance the effects of multidrug resistance. Plants represent a viable platform for such endeavors owing to their traditional relevance in infectious disease therapies as well as their vast chemical resources. As many as fifty different species of the Amaryllidaceae are discernible with such functions in traditional medicine, thirty-nine of which have been subjected to pharmacological evaluations. Submicromolar antibacterial activities for several of these plants have been the driving force behind studies targeting their active constituents. This review accounts for close to a hundred of such entities, mainly isoquinoline alkaloids, which have been the focus in assays of thirty different bacterial pathogens. Promising activities were detected in several instances, although disappointingly the submicromolar level could not be breached. Also considered are structure-activity relationships which have emerged within the various groups of Amaryllidaceae alkaloids.

Garlic mustard, Alliaria petiolata (M. Bieb.) Cavara & Grande, a European biennial, has become common in many Midwestern and eastern North American forests. Researchers have sometimes documented a two-year (two-point) population cycle in which the vegetative and reproductive phases alternate in abundance. However, little research has been conducted on the scale dependence of the two-point cycle and the extent to which the cycle is dependent on the density of A. petiolata. In addition to this interest in A. petiolata's population dynamics, researchers have investigated A. petiolata's effects on other plant species, often concluding that it displaces native herbs and inhibits tree seedling growth and survival through the production of allelochemicals. In order to examine both the population dynamics of A. petiolata and its possible effects on North American native plants, we conducted a four year study in which we monitored A. petiolata in a 6.2 ha portion of a Minnesota oak (Quercus) woodland at t...

The nucleation hypothesis appears to explain widespread patterns of succession in tropical pastures, specifically the tendency for isolated trees to promote woody species recruitment. Still, the nucleation hypothesis has usually been tested explicitly for only short durations and in some cases isolated trees fail to promote woody recruitment. Moreover, at times, nucleation occurs in other key habitat patches. Thus, we propose an extension, the matrix discontinuity hypothesis: woody colonization will occur in focal patches that function to mitigate the herbaceous vegetation effects, thus providing safe sites or regeneration niches. We tested predictions of the classical nucleation hypothesis, the matrix discontinuity hypothesis, and a distance from forest edge hypothesis, in five abandoned pastures in Costa Rica, across the first 11 years of succession. Our findings confirmed the matrix discontinuity hypothesis: specifically, rotting logs and steep slopes significantly enhanced woody colonization. Surprisingly, isolated trees did not consistently significantly enhance recruitment; only larger trees did so. Finally, woody recruitment consistently decreased with distance from forest. Our results as well as results from others suggest that the nucleation hypothesis needs to be broadened beyond its historical focus on isolated trees or patches; the matrix discontinuity hypothesis focuses attention on a suite of key patch types or microsites that promote woody species recruitment. We argue that any habitat discontinuities that ameliorate the inhibition by dense graminoid layers will be foci for recruitment. Such patches could easily be manipulated to speed the transition of pastures to closed canopy forests.

This study offers a unique contribution to the literature by investigating the influential factors of energy-related, carbon dioxide emission intensity among a panel of 30 provinces in China covering the period 1991–2010. We use novel spatial panel data models to analyze the drivers of energy-related emission intensity, which we posit are characterized by spatial dependence. Our results suggest (1) emission intensities are negatively affected by per-capita, province-level GDP and population density; (2) emission intensities are positively affected by the structure of energy consumption and the transportation sector; and, (3) energy prices have no effect on emission intensities.

The discovery of the karrikin class of plant growth regulators (PGRs) is a milestone accomplishment in plant biochemistry and physiology, with significant potential in agriculture and horticulture. These compounds have in common a fused furano-pyran ring system featuring various permutations of methyl substitution. Chief amongst these compounds is karrikinolide (KAR1), identified as the key germination stimulant present in plant-derived smoke, which together with five other closely-related structures (KAR2–KAR6) make up the karrikin class of PGRs. By contrast, the germination inhibitor 3,4,5-trimethyl-2(5H)-furanone has also been identified in plant-derived smoke. Various synthetic endeavours have been undertaken for structure–activity relationship study purposes as well as to probe the molecular mechanics of these compounds. In this study, syntheses of KAR1, KAR3 and S-KAR1 were carried out and their structures verified by X-ray crystallography. Effects on germination were measured against the inhibitor 3,4,5-trimethyl-2(5H)-furanone in Grand Rapids lettuce seeds. X-ray crystallographic data and germination promotory activity for S-KAR1 are described for the first time.

Ethnopharmacological relevance Boophone disticha is the most common member of the South African Amaryllidaceae used extensively in traditional medicine of the various indigenous population groups, including the Sotho, Xhosa and Zulu as well as the San. This survey was carried out to identify and highlight areas relevant to the traditional usage of Boophone disticha. Pharmacological aspects were examined with the purpose of reconciling these with the traditional usage of the plant. In relation to phytochemical make-up, particular attention was paid on how its alkaloid constitution might corroborate the various biological effects manifested by the plant. Materials and methods Information gathering involved the use of four different database platforms, including Google Scholar, ScienceDirect, SciFinder® and Scopus. Arrangement and detailing of this information is as reflected in the various sections of the paper. Results Sixteen categories were identified under which Boophone disticha finds use in traditional medicine. These were shown to include general usage purposes, such as ‘cultural and dietary’, ‘well-being’, ‘personal injury’, ‘divinatory purposes’, ‘psychoactive properties’ and ‘veterinary uses’. Furthermore, traditional usage was seen to involve six body systems, including functions pertaining to the circulatory, gastrointestinal, muscular, neurological, respiratory and urinary systems. The four remaining categories relate to use for inflammatory conditions, cancer, malaria and tuberculosis. Overall, three areas were discernible in which Boophone disticha finds most usage, which are (i) ailments pertaining to the CNS, (ii) wounds and infections, and (iii) inflammatory conditions. In addition, several aspects pertaining to the toxic properties of the plant are discussed, including genotoxicity, mutagenicity and neurotoxicity. Conclusion The widespread ethnic usage of Boophone disticha has justified its standing as a flagship for the Amaryllidaceae and its relevance to South African traditional medicine. Furthermore, its promising pharmacological and phytochemical profiles have stimulated significant interest in the clinical realm, especially in the areas of cancer and motor neuron disease chemotherapy. These collective properties should prove useful in steering the progress of the plant towards a wider audience.

Plants have long served as a first line of defense response to malaria. They have also spawned several classes of antimalarial drugs such as quinine and artemisinin. However, most if not all of these drugs have succumbed to multidrug resistance, thus reigniting interest in the identification of novel chemotherapies against this parasitic disease. The starting point for many of such endeavors lies with the plants themselves whose extracts have served as herbal remedies, which originate from traditional medicine (TM). Several species of the Amaryllidaceae have been shown to have such functions in TM. This survey examines those plants of the family, which have hitherto been examined for antiplasmodial effects against the malarial parasite Plasmodium falciparum. Also considered are the alkaloid constituents of these plants, which have demonstrated activities against various strains of the pathogen. Particular emphasis is made on those plants which both demonstrate such activity as well as have a place in traditional therapies for malaria.

article i nfo The "large sour plum" tree Ximenia caffra Sond. (Olacaceae) is the only African representative of the genus Ximenia L., with a distribution covering East Africa, from Tanzania in the north to South Africa, as well as parts of Botswana and Namibia. It has many uses in traditional medicine, including treatment of wounds and infections as well as diarrhea, which have been verified through various pharmacological studies. Fur- thermore, the plant is also known for its nutritional and cosmetic value. Its edible fruits are known to be high in protein, potassium and vitamin C, while the seed oil, also referred to as "Ximenia oil" is rich in long chain unsaturated fatty acids and finds use as a domestic biofuel, with characteristics amenable to cosmetic development as topical applicants. Extracts of the plants are also widely used for treating sexually transmit- ted infections (STIs), which has been verified through ethnobotanical surveys and pharmacological screens. Based on these observations, X. caffra var. caffra was examined for its phytochemical composition and activity against the gonorrheal pathogen Neisseria gonorrhoeae. Initially, the leaf ethanolic extract was seen to be ac- tive (43.9% inhibition). The DCM partition of this extract (with 78.8% inhibition) was subjected to bioassay guided fractionation leading to the identification of the bisnorsesquiterpene vomifoliol which exhibited sig- nificant activity (63.1%) against N. gonorrhoeae.

China is one of the world’s most rapidly growing countries and the largest consumer of energy in the world. As a result, China’s pollution emissions almost doubled from 2002 to 2007, and in 2006 it surpassed the United States to become the world’s top carbon dioxide emitter. Understanding the sources of emissions is essential towards designing policies aimed at curbing carbon emissions in China. The surge in China’s exports has been partially blamed for this increase in emissions. To understand the sources of emissions, this study uses a vector autoregression model to examine the relationship among exports, CO2 emissions, coal consumption and trade openness in China for the years 1970–2010. The study uses a modified version of Granger Causality developed by Toda and Yamamoto [56]. The main findings within the study indicate: (1) Granger Causality running from exports to emissions; (2) Granger Causality running from coal consumption to exports; and (3) GDP determines future variability in exports and CO2 emissions. Results suggest that governmental policies aimed at controlling coal consumption could affect CO2 emissions and exports. Results from this study should assist in formulating policies to mitigate both CO2 emissions and coal consumption.

West Valley Demonstration Project (WVDP) Annual Site Environmental Report (ASER) for Calendar Year 2014. The report, prepared for the U.S. Department of Energy West Valley Demonstration Project office (DOE-WVDP), summarizes the environmental protection program at the WVDP for calendar year (CY) 2014. Monitoring and surveillance of the facilities used by the DOE are conducted to verify protection of public health and safety and the environment. The report is a key component of DOE’s effort to keep the public informed of environmental conditions at the WVDP. The quality assurance protocols applied to the environmental monitoring program ensure the validity and accuracy of the monitoring data. In addition to demonstrating compliance with environmental laws, regulations, and directives, evaluation of data collected in 2014 continued to indicate that WVDP activities pose no threat to public health or safety, or to the environment.

We discuss the benefits that a collaborative research network, a group of faculty from different institutions who jointly conduct a research project, can have on undergraduate research (UR) by enhancing the diversity and significance of projects and by improving student motivation and breadth of learning. The main example used is the Ecological Research as Education Network (EREN), founded in 2010 to enhance undergraduate research in ecology at primarily undergraduate institutions (PUIs) by (1) providing networking and collaborative research opportunities for both faculty and students and (2) developing free educational resources. EREN comprises about 280 ecology faculty and staff nationally and has facilitated development of nine continental-scale, collaborative research projects. Project leaders design a research project that can be conducted by faculty and students at just about any college. Faculty and their students carry out the data collection at their home institution and submit it to the publicly available project database. Then participants (and even non-participants) can avail themselves of the large, multi-year, continent-wide data set. Substantial benefits have been reported for programs, faculty, and students. Undergraduate research programs are broadened and faculty benefit because they gain insights and laboratory techniques from colleagues in other institutions and fields, thereby expanding the diversity of potential undergraduate research projects and resulting in more broadly trained undergraduates. The research projects themselves have become educational resources incorporated into courses at all levels, as well as independent research projects. Because data collection happens nationwide, college faculty and students at small colleges are now able to investigate large-scale ecological questions. Preliminary assessments have shown significant improvements for some student-learning outcomes, including thinking across scales, use of best practices in data management, and describing scientific collaboration techniques. Students demonstrate increased motivation and retention through participation in a nationwide, authentic research project with publication-quality data, becoming part of a community of scholars and gaining a sense of belonging and responsibility. Despite challenges with coordination and communication, students are exposed to a wider range of techniques and subfields of ecology than they would be without this network.

The Amaryllidaceae alkaloids are a group of isoquinoline alkaloids with a distinct array of structural diversity. These compounds have attracted widespread attention due to their manifold biological properties, of which their significance in motor neuron disease through the clinical representative galanthamine is most striking. The cytotoxic potential of Amaryllidaceae alkaloids has also been gaining ground following the advancement of its phenanthridones pancratistatin and narciclasine into clinical trials. This progress has sparked considerable interest in this plant family as a sustainable source of potential anticancer chemotherapeutics. Given this background, this review seeks to (1) examine the cytotoxic effects of Amaryllidaceae alkaloids in cancer cell lines, (2) provide a structural and pharmacophoric basis to these effects, and (3) highlight the various molecular mechanisms behind these activities.

Nine Brazilian Amaryllidaceae species were studied for their alkaloid composition and acetylcholinesterase (AChE) inhibitory activity via GC?MS and a modified Ellman assay, respectively. A total of thirty-six alkaloids were identified in these plants, of which Hippeastrum papilio and H. glaucescens exhibited the highest galanthamine content and the best IC50 values against AChE. Furthermore, Hippeastrum vittatum and Rhodophiala bifida also showed notable AChE inhibitory effects. X-ray crystallographic data for four galanthamine-type compounds revealed significant differences in the orientation of the N-methyl group, which are shown to be related to AChE inhibition. Fil: de Andrade, Jean Paulo. Universidad de Barcelona; España. Universidade Federal do Rio Grande do Sul; Brasil. Universidad del Espiritu Santo; Brasil Fil: Giordani, Raquel B.. Universidade Federal do Rio Grande do Sul; Brasil Fil: Torras-Claveria, Laura. Universidad de Barcelona; España. Universidad del Espiritu Santo; Brasil Fil: Pigni, Natalia Belen. Universidad de Barcelona; España. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; Argentina. Universidade Federal do Rio Grande do Sul; Brasil Fil: Berkov, Strahil. Universidad de Barcelona; España. AgroBioInstitute; Bulgaria. Universidad del Espiritu Santo; Brasil Fil: Font-Bardia, Mercè. Universidad de Barcelona; España Fil: Calvet, Teresa. Universidade Estadual de Campinas; Brasil Fil: Konrath, Eduardo Luis. Universidade Federal do Rio Grande do Sul; Brasil. Universidad del Espiritu Santo; Brasil Fil: Bueno, Kelly. Universidade Federal do Rio Grande do Sul; Brasil Fil: Sachett, Liana G.. Universidade Federal do Rio Grande do Sul; Brasil Fil: Dutilh, Julie H.. Universidade Estadual de Campinas; Brasil. Universidad del Espiritu Santo; Brasil Fil: de Souza Borges, Warley. Universidad del Espiritu Santo; Brasil Fil: Viladomat, Francesc. Universidad de Barcelona; España Fil: Henriques, Amelia T.. Universidade Federal do Rio Grande do Sul; Brasil Fil: Nair, Jerald J.. Universidad de Barcelona; España Fil: Zuanazzi, José Angelo S.. Universidade Federal do Rio Grande do Sul; Brasil Fil: Bastida, Jaume. Universidad de Barcelona; España

Garlic mustard, Alliaria petiolata (M. Bieb.) Cavara & Grande, is an introduced biennial forb that has commonly been referred to as highly invasive and as having substantial negative effects on other plants in the eastern deciduous forests of North America. However, several recent studies have documented only modest effects on other plant species, raising questions as to the extent of the threat really posed by A. petiolata. Alliaria petiolata often exhibits an alternating two-year life-history cycle, with high rosette years alternating with high flowering stem years. It has been proposed that this cycle is partly driven by intraspecific competition between the stems and the rosettes. In a two-year study, we extensively sampled A. petiolata in a Minnesota woodland at two spatial scales, including 6.5 km of belt transects in a 6.8 ha study grid (20 × 20 m cells) and 90 small sampling quadrats (1.0 × 0.5 m) within the grid. At the large scale, we compared seed bank abundance and diversity of other ...

Several of the Amaryllidaceae alkaloids are known for their cytotoxic properties, of which the lycorine group representatives are prominent for potent and cell line specific antiproliferative activities. As a distinct niche within the lycorine group, the phenanthridones, exemplified by narciclasine and pancratistatin, have shown much promise as remarkably selective cytotoxic agents and are presently at various stages of development, with a clinical candidate likely to appear on the market within the next decade. The crinane group of the Amaryllidaceae has also spawned several molecules, such as crinamine and haemanthamine, with promising cytotoxic activities. In the present study, the β-crinane distichamine as well as the phenanthridone narciprimine, both rare constituents of the Amaryllidaceae, are revealed as novel antiproliferative agents. Apoptosis-inducing effects are demonstrated for distichamine in human acute lymphoblastic leukemia (CEM) cells. These findings provide further insights to the structural details of the apoptosis-inducing pharmacophores resident within both series of alkaloids.

Cycads are a group of slow-growing, perennial, dioecious plants which in geological times thrived during the Mesozoic era. The present worldwide complement of around 300 species is distributed through both tropical and subtropical regions of the globe, and has pronounced centres in Australia, Mexico and South Africa. These popular plants are known for their ornamental, economic, dietary and medicinal value. However, increased demand collectively from this sector, as well as decimation of large tracts of cycad populations in the wild through habitat destruction and unscrupulous collection, has precipitated a fragile conservation status for the family, with majority of its species listed as threatened by statutory bodies such as CITES and IUCN. Despite their popularity, cycads have for several centuries been known to be toxic. The plants have been shown to have carcinogenic, mutagenic, teratogenic and neurotoxic properties, and its major constituent principles macrozamin and cycasin have exhibited similar effects in model studies. Cycads are used widely in traditional medicine (TM) in South Africa and the majority of endemic species are commonly traded on local TM markets. The present study deals with the isolation of macrozamin from seed kernels of Encephalartos transvenosus and quantification of this toxic methylazoxymethanol (MAM) glycoside via HPLC in selected indigenous species.

Ethnopharmacological relevance Boophone disticha (Amaryllidaceae) is one of the most common bulbous plants used for medicinal purposes by the indigenous people of southern Africa. Its use as a narcotic substance by the Khoi/San tribes has been known for several centuries, while the Sotho, Xhosa and Zulu people are known to use the plant to treat a host of ailments, including inflammation, wounds, gynaecological conditions and psychosis. Aim of the study Much of the pharmacological work on the plant, such as affinity to the serotonin transporter, has been based on its reputed usage for narcotic purposes. However, its widespread use to treat wounds and infections has not been linked to a specific chemical entity. In this regard, Boophone disticha was here examined for its phytochemical composition which could shed light on the use of the plant for such purposes. Materials and methods The known crinane alkaloids buphanidrine and distichamine were isolated via column chromatography of the ethanolic extract of bulbs of Boophone disticha. Structural details of the compounds were determined by high field 2D NMR and mass spectroscopic techniques. Microbial activity against selected Gram-positive and Gram-negative bacteria was ascertained according to the micro-dilution assay. Results Both buphanidrine and distichamine were uncovered as novel, broad spectrum moderately active, antibacterial agents with the best MIC value detected at 0.063 mg/ml for Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae. MIC values for Bacillus subtilis were two-fold less than that observed for the other three bacteria, suggesting that the extract and pure compounds were selective in their interaction with the bacterial pathogens. Conclusion Phytochemical investigation of Boophone disticha has led to the identification of two known crinanes, buphanidrine and distichamine. Based on the reputed traditional use of the plant for wounds and infections, both compounds were screened for antibacterial activity which revealed them to be novel, broad spectrum antibacterial agents with the best MIC value set at 0.063 mg/ml. Their close structural similarity may have bearing on their similar activity profiles.