Grindelia Squarrosa Research Articles

Flora of the riverside-water side of the lower section of the Nistru river and its tributaries on the territory of the Republic of Moldova

The studied section of the river. The Dniester and its tributaries are represented by 113 species, 103 genera from 55 families of higher plants (Magnoliophyta). The greatest diversity is found in the Asteraceae (21 species) and Poaceae (8 species) families. About 1/3 of the total number of species are represented by the Eurasian element. The spontaneous element of the studied flora is represented by 54 species, and the ruderal element by 36 species. Invasive elements are represented by the species Ailanthus altissima (Mill.) Swingle, Acer negundo L. Amorpha fruticosa L., Ambrosia artemisiifolia L., Grindelia squarrosa Willd.. It was also carried out for all species: determination of the percentage ratio of life forms, biological indices, ecological groups in relation to humidity, the ratio of plant species by origin, the distribution of indicator species by nitrogen (N) in percentage terms and the ratio of plant species in relation to the category trophicity.

Essential Oil Composition of Grindelia squarrosa from Southern Idaho.

Grindelia squarrosa is an arid lands herb that has been used in Native American traditional medicine, is a potential source of pharmacologically active compounds, and has been explored as a source of biofuel. The purpose of this work was to examine the essential oil composition of G. squarrosa from southern Idaho. Gas chromatographic methods revealed the essential oil of G. squarrosa var. serrulata to be rich in monoterpenoids, α-pinene (21.9%), limonene (17.1%), terpinolene (10.6%), and borneol (6.5%). The essential oil composition of G. squarrosa from Idaho is similar to that previously reported from specimens collected from Montana and confirms the volatile phytochemistry of plants growing in North America. The major essential oil components were screened for antimicrobial activity against respiratory and dermal pathogens. (-)-β-Pinene showed strong antibacterial activity against Streptococcus pneumoniae (MIC 39.1 μg/mL) and (-)-borneol showed strong activity against Staphylococcus aureus (MIC 78.1 μg/mL).

NEW DATA ON THE DISTRIBUTION AND INVASION STATUS OF SOME ALIEN PLANTS IN ROMANIA

In this paper we report new chorological data for 20 alien plant taxa from the vascular flora of Romania. A total of 9 species (Campsis radicans, Euphorbia glyptosperma, Grindelia squarrosa, Impatiens balfourii, Oenothera suaveolens, Robinia x ambigua, Rudbeckia triloba, Sedum sarmentosum, Setaria faberi) are reported as new to the regional floras within the country. Oenothera pycnocarpa and Dittrichia graveolens are reported in their second and the third sites in Romania, respectively. For the remaining 9 species (Cytisus scoparius, Dysphania pumilio, Eleusine indica, Erigeron sumatrensis, Eriochloa villosa, Oenothera depressa, Paspalum distichum, Rosa rugosa and Sicyos angulatus), we provided new field data, to improve knowledge on their current distribution and invasion status. All taxa are neophytes, introduced either accidentally (11 taxa) or deliberately (9 taxa), more than half of which are currently invasive or potentially invasive in the country.

Особенности распространения Grindelia Squarrosa в степных экосистемах различной степени инвазионной емкости на территории Волгоградской области

One of the nowaday acute environmental and fundamental ecological problems is the spread of invasive species, that averaging, “cosmopolitanizing” ecosystems of different ranks, which leads to a loss of originality and stability of the biosphere. A significant driving factor in this process became a human actively moving many species from continent to continent, intentionally or accidentally introducing them into various indigenous biomes. One of the brightest representatives of the American origin adventitious flora is Grindelia squarrosa (Pursh) Dunal, actively capturing anthropogenically disturbed territories. The article presents the results of long-term studies of peridromic plant communities exposed to the negative effects of various anthropogenic factors. The analysis of the influence of grindelia on the species diversity of communities and the vital indicators of neighboring plants indicates the high invasiveness of the studied species and its detrimental effect on the phytocenoses of anthropogenically altered dry-steppe landscapes of the Volgograd region. The article suggests the use of the term “peridromic” – geographically and functionally connected with the road. The article outlines the directions of further scientific research concerning the causes of the speed and heterogeneity of the spread of grindelia thickets.

Invasive species of the flora of transformed sections of railway tracks in the bottom of the Dnister–Tiligul river

In order to study invasive species as dangerous elements of foreign flora, modern monitoring studies are needed under the conditions of various ecotopes of a wide range of their transformation. According to the «Strategy of biosecurity and biological protection», alien species are a threat to biodiversity at its various levels. Taking into account that railway tracks are one of the main ways of penetration and initial establishment of synanthropic species in new territories, in 2018–2021, the flora of the tracks in the areas of the Dniester floodplain was studied. 34 invasive species from 14 families were noted, they included Asteraceae (26.47% of species), Brassicaceae and Poaceae (17.65% each), Amaranthaceae (8.82%) and others. The majority of species (55.88%) grows both on track sections and (in addition) next to ruderalized sections of overburden. Another 11 species (32.35%) can be found on tracks, ruderalized areas of overburden and on the roadsides of the nearby highway. Only two species (5.88%) are cultivated. Two more species such as Amaranthus powellii S.Watson, Oxybaphus nyctagineus (Michx.) Sweet are noted only on railway tracks and sections of railway infrastructure. According to the life form, nine species (26.47%) are hemicryptophytes. 23 ones are therophytes (67.65%). Two species are fanerophytes (5.88%). According to the chronotype, 41.18% of the species are aschaeophytes. Kenophytes make 58.82%. Among archaeophytes, most plant species have a frequency of occurrence — «scattered» and «abundant» (35.71% each). Among the kenophyres, there are the most species whose plants were «scattered» (40.00%). In general, the majority of invasive species, by frequency of occurrence, belong to the «scattered» (38.25%) and «abundant» (23.53%) categories. Also there are «single» (17.65%), «usually» (11.77%), «single locality» (8.82%). Most species (70.60%) are represented by wide ranges: cosmopolitan (and hemi-cosmopolitan) make 44.12%, Eurasian form 14.71%, Euro-American make 11.77%. Eight species (23.53%) are particularly dangerous for the environment, as they are transformers of local growth. Most of the plants of invasive species of railway tracks were also found on adjacent ruderalized areas. Therophytes, kenophytes and species with a wide range prevail. They are found, mostly «scattered» and «abundant». Eight species (23.53%) are the most dangerous for environment, because they transform ground place (Ambrosia artemisiifolia, Centaurea diffusa, Conyza canadensis, Grindelia squarrosa, Iva xanthiifolia, Elaeagnus angustifolia, Anisantha tectorum, Setaria glauca).

Neutrophil Immunomodulatory Activity of (-)-Borneol, a Major Component of Essential Oils Extracted from Grindelia squarrosa.

Grindelia squarrosa (Pursh) Dunal is used in traditional medicine for treating various diseases; however, little is known about the immunomodulatory activity of essential oils from this plant. Thus, we isolated essential oils from the flowers (GEOFl) and leaves (GEOLv) of G. squarrosa and evaluated the chemical composition and innate immunomodulatory activity of these essential oils. Compositional analysis of these essential oils revealed that the main components were α-pinene (24.7 and 23.2% in GEOFl and GEOLv, respectively), limonene (10.0 and 14.7%), borneol (23.4 and 16.6%), p-cymen-8-ol (6.1 and 5.8%), β-pinene (4.0 and 3.8%), bornyl acetate (3.0 and 5.1%), trans-pinocarveol (4.2 and 3.7%), spathulenol (3.0 and 2.0%), myrtenol (2.5 and 1.7%), and terpinolene (1.7 and 2.0%). Enantiomer analysis showed that α-pinene, β-pinene, and borneol were present primarily as (−)-enantiomers (100% enantiomeric excess (ee) for (−)-α-pinene and (−)-borneol in both GEOFl and GEOLv; 82 and 78% ee for (−)-β-pinene in GEOFl and GEOLv), while limonene was present primarily as the (+)-enantiomer (94 and 96 ee in GEOFl and GEOLv). Grindelia essential oils activated human neutrophils, resulting in increased [Ca2+]i (EC50 = 22.3 µg/mL for GEOFl and 19.4 µg/mL for GEOLv). In addition, one of the major enantiomeric components, (−)-borneol, activated human neutrophil [Ca2+]i (EC50 = 28.7 ± 2.6), whereas (+)-borneol was inactive. Since these treatments activated neutrophils, we also evaluated if they were able to down-regulate neutrophil responses to subsequent agonist activation and found that treatment with Grindelia essential oils inhibited activation of these cells by the N-formyl peptide receptor 1 (FPR1) agonist fMLF and the FPR2 agonist WKYMVM. Likewise, (−)-borneol inhibited FPR-agonist-induced Ca2+ influx in neutrophils. Grindelia leaf and flower essential oils, as well as (−)-borneol, also inhibited fMLF-induced chemotaxis of human neutrophils (IC50 = 4.1 ± 0.8 µg/mL, 5.0 ± 1.6 µg/mL, and 5.8 ± 1.4 µM, respectively). Thus, we identified (−)-borneol as a novel modulator of human neutrophil function.

Alien plant invasion in the ruderal vegetation of Ukraine

Abstract The article presents the results of an analysis of the alien flora of the ruderal vegetation of Ukraine. A total of 325 alien species which belong to 58 families and 198 genera were identified. The total anthropogenization index of the ruderal phytocoenoses is 19.8%. It was established that the highest level of anthropogenization was found in the phytocoenoses of Polygono-Poetea annuae, Stellarietea mediae and Plantaginetea majoris. The leading families of the non-native fraction of the studied plant communities were Asteraceae, Brassicaceae and Poaceae. It has been revealed that in the biomorphological spectrum of alien plants therophytes prevailed. The ecological analysis has shown the predominance of submesophytes, acidophytes, semieutrophytes, acarbonatophytes and heminitrophytes plants. It was established that according to the arrival time the kenophytes predominate and by the degree of naturalization – the epoecophytes. Comparison of the alien species composition of the ruderal plant communities by means of Jaccard’s indices showed the most similarity between the classes Polygono-Poetea annuae and Plantaginetea majoris, Robinietea and Galio-Urticetea, Stellarietea mediae and Artemisietea vulgaris. For the separate classes the indices of archaeophytization, kenophytization, modernization and fluctuation of the flora were calculated. It has been established that there are 23 highly invasive species in the ruderal vegetation of Ukraine and among these Ambrosia artemisiifolia, Anisantha tectorum, Grindelia squarrosa, Heracleum mantegazzianum, H. pubescens and Xanthium oreintale ssp. riparium are transformers.

Grindelia squarrosa in Ukraine: current distribution and ecological and coenotic peculiarities

Abstract Grindelia squarrosa (Pursh) Dunal. (Asteraceae) is a species with high invasiveness capacity in Ukraine, especially in the Steppe zone. The first data on the finding of escaped plants in Europe were recorded in the 40’s of the last century. There were three naturalization centres in Ukraine, from where the species began to spread. In the secondary range in Ukraine, G. squarrosa is characterized by high levels of seed productivity and germination, variable modes of dispersal, wide ecological and coenotic amplitudes and CSR-strategy. The trend continues with the spread of the species in western, north-western and northern directions, and today more than 300 localities confirming this trend are already known. In the past 20 years, 92 new localities have been recorded. G. squarrosa is a transformer, widespread in the southern regions of the Steppe zone. As a result, new plant communities are formed. In general, this species is recorded in communities of five vegetation classes. In terms of ecological indicators, the optimum of the species is in the Steppe zone. It can be predicted that, due to the potential ability of the species to adapt and under the influence of climatic change, there is a higher probability that the species will spread in the future in northern and western directions. The condition for such an expansion is disturbance of meadow-steppe fringe xeromesic communities, with decreased coenotic competition.

Nematicidal activity of aqueous tinctures of plants against larvae of the nematode Strongyloides papillosus.

This research was undertaken to evaluate the nematicidal activity of various concentrations of aqueous tinctures of 80 plant species towards L1-2 of S. papillosus. For the experiment with larvae of S. papillosus, there were used 0.19%, 0.75% and 3.00% aqueous tinctures of plants. Out of 80 tested species, nematicidal activity against L1-2 of S. papillosus was displayed by 20 plants. The greatest activity (LC50 = 0.060-0.069%) towards larvae of S. papillosus was exerted by Teucrium polium, Achillea millefolium, Genista tinctoria and Ulmus laevis. Less expressed nematicidal activity (LC50 = 0.070-0.079%) was recorded for Thalictrum minus, Stachys recta, Falcaria vulgaris, Lavatera thuringiaca. Even lower effect (LC50 = 0.080-0.089%) was shown by aqueous tinctures of Mentha × piperita, Achillea millefolium, Salvia nutans, Eryngium campestre and Cerasus fruticosa. The following plants could be arranged in declining order of effectiveness of nematicidal activity (LC50 = 0.090-0.165%) Malus sylvestris, Tragopogon orientalis, Erigeron annuus, Grindelia squarrosa, Urtica dioica, Daucus carota, Medicago sativa, Carduus acanthoides, Ulmus minor and Hieracium umbellatum. A far weaker effect on the nematodes was displayed by Bromopsis inermis and Tragopogon podolicus. Aqueous tinctures of 60 other studied species of plants exhibited low nematicidal activity in 3.00% aqueous tincture, while in 0.19% and 0.75% aqueous tinctures, no nematicidal activity was seen. The results of the research suggest that in the conditions of natural ecosystems, some species of plants of the Apiaceae, Asteraceae, Fabaceae, Lamiaceae, Malvaceae, Rosaceae, Ulmaceae and Urticaceae families could reduce vitality of free-living L1-2 larvae of S. papillosus.

Grindelia squarrosa Extract and Grindelic Acid Modulate Pro-inflammatory Functions of Respiratory Epithelium and Human Macrophages.

Aim of the study: Both nasal and bronchial epithelial cells have evolved sophisticated mechanisms involved in cellular response to bacterial infection. Recognition of pathogens by TLR receptors activate the NF-κB transcription factor, and lead to production of wide spectrum of cytokines (TNF-α, IL-1β, IL-6 and IL-8). Released by epithelium proinflammatory cytokines intensify migration of macrophages to damaged tissues and modulate their pro-inflammatory functions. Based on traditional use of G. squarrosa aerial parts we hypothesized that successful treatment of cold-related diseases may arise from modulation of the pro-inflammatory functions of respiratory epithelium and human monocytes/macrophages. The biological activity of G. squarrosa extract and grindelic acid were compared with clarithromycin and budesonide used as positive controls. Methods: The expression of surface receptors (TLR-4, IL-10) and expression of adhesive molecules (ICAM-1, VCAM-1, E-selectin) was analyzed with flow cytometry. The macrophage attachment to the epithelial cells was assessed fluorimetrically. The p65 NF-κB concentration and cytokine production was measured spectrophotometrically using enzyme-linked immunosorbent assay. Antibacterial activity was examined by the standard disc-diffusion method and serial dilution method according to CLSI guidelines. Results: G. squarrosa extract and grindelic acid had no antimicrobial effect. However, we noticed significant modulation of pro-inflammatory functions of LPS-stimulated nasal and bronchial epithelium. G. squarrosa extract treatment resulted in decrease of TLR-4 expression and p65 NF-κB concentration and inhibition of cytokines synthesis (IL-8, TNF-α, IL-1β and IL-6) in both cellular models. Additionally, G. squarrosa extract slightly modulated ICAM-1 expression affecting on attachment of macrophages to epithelium. Only G. squarrosa extract was able to stimulate the anti-inflammatory functions of macrophages by inducing TGF-β release and IL-10 receptor surface expression. Grindelic acid, identified as a dominant compound in the plant extract, modulated pro-inflammatory functions of epithelium and macrophages slightly. Conclusion: The obtained results support traditional use of Grindelia squarrosa preparations for a treatment cold-associated diseases symptoms. In our opinion, the observed biological effect of extract may be a consequence of synergistic effect of all compounds present in the extract.

Effect of supercritical water temperature and Pd/C catalyst on upgrading fuel characteristics of gumweed-derived solvent-extracted biocrude

Grindelia squarrosa, known as gumweed, is a shrub that grows in arid lands in North America with up to 8% biocrude (or bio-oil) content that can be extracted by using a common solvent extraction method. This solvent-extracted biocrude (SEB) has nearly 24 wt% oxygen, which is not suitable for direct combustion as a bio-oil or biodiesel. In this study, supercritical water (SCW) upgrading is used to reduce the oxygen of the SEB and increase the fuel value by creating lighter oil fractions. Treatment for 30 min reduces the oxygen content from 24.1 ± 1.6 (for raw SEB) to 7.2 ± 0.7%, 7.1 ± 0.4%, and 6.9 ± 0.6% at 380, 400, and 420 °C respectively. The addition of palladium on carbon (Pd/C) catalyst at 400 °C further reduces the oxygen content to 4.8 ± 0.7%. This removal in oxygen content is shown in the reduction of carboxylic acid compounds in the oils. Without having to use hydrogen, such as with the traditional hydrodeoxygenation process, the SCW upgrading has rather high energy yields for the oils which all have higher heating values between 41.0 and 42.8 MJ kg−1 (with no significant effect of temperature or catalyst). Treatment at 400 °C had the highest energy yield at 76.4 ± 1.7%, and treatment with the Pd/C catalyst at 400 °C had the lowest at 61.4 ± 2.8%. These energy yields, higher heating values, and low oxygen contents show that SCW can effectively be used to convert gumweed-derived SEB into a valuable bio-oil.

A comparison of the flora of the Chop (Ukraine) and Čierna nad Tisou (Slovakia) border railway stations

The diversity of vascular plant species at two border railway stations, Chop in southwestern Ukraine and Cierna nad Tisou in southeastern Slovakia, was studied and compared. The Chop station flora consisted of 240 taxa, while Cierna nad Tisou had 309 taxa. 173 taxa were common to both stations, 67 taxa occurred only in Chop and 136 only in Cierna nad Tisou. Native species prevailed over alien at both stations; neophytes dominated over archaeophytes in Chop, whereas archaeophytes were dominant in Cierna nad Tisou. The floristic composition of the Chop and Cierna nad Tisou railway stations included species which were mostly hemicryptophytes and therophytes, with European and Asian origin, predominantly insect pollinated, reproducing by seeds, mostly competitors, urbanoneutral or moderately urbanophobic, and growing in habitats moderately influenced by human activity. The native species were predominantly urbanophobic hemicryptophytes while the alien species were mainly urbanophilic therophytes that were more thermophilous than the natives. The most abundant families at both stations were Asteraceae and Poaceae. The greater species diversity in Cierna nad Tisou and the differences in species composition between the stations probably arise from the size, structure and treatment of the station, the station surroundings, and the size of the associated city. Species Euphorbia davidii, Galeopsis angustifolia, Geranium purpureum, and Grindelia squarrosa are discussed as examples of ferroviatic species migration.

Особливості онтогенезу Grindelia squarrosa в популяціях зі сходу України

Особливості онтогенезу Grindelia squarrosa в популяціях зі сходу України

Screening research of 90% aqueous ethanolic plant extracts antimicrobial activity against Propionobacterium acnes — an etiological factor of acne occurrence

Annotation. Prolonged antibacterial therapy of acne, mainly by antibiotics of MLS-group (macrolides, lincosamides and streptogramin B), has a number of side effects, the main of which is the emergence of resistant strains. Considering the risks and side effects of traditional etiotropic acne therapy, the use of herbal medicines may be an alternative of this disease treatment. The purpose of this study was to perform a screening study of 90% aqueous-ethanolic medicinal plant extracts antimicrobial activity against P acnes test strains. Antimicrobial activity of 242 aqueous-ethanolic extracts of 183 medicinal and aromatic plants of various organs against two P. acnes strains: sensitive and MLS resistant by HB (Heart Brain) agar diffusion method was studied. Statistical processing of results has been caried by UTHSCSA ImageTool 2.0, Microsoft Office Excel 2011. Eupatorium cannabinum L. and Grindelia squarrosa (Pursh) Dun. aerial parts, Populus nigra L. fruits and needles, Helichrysum arenarium L., Evernia prunastri (L.) Ach. herbs, Calendula officinalis L. flowers, Geranium pratense L. rhizomes and Larix decidua Mill. needles exhibited strong antimicrobial activity (diameter of growth inhibition≥ 15 mm) against test strains. Representatives with antimicrobial properties against acne agents have been found among medicinal plants of Ukraine's flora. The detection of pronounced antimicrobial properties in various pharmacopoeial and non-pharmacopoeial plants necessitates the need for phytochemical study of the raw material to isolate and identify its active components.

Curlycup gumweed (Grindelia squarrosa(Pursh) Dunal [Asteraceae]): a native forb candidate for inclusion in Great Basin greenstrips

Curlycup gumweed (<i>Grindelia squarrosa</i>(Pursh) Dunal [Asteraceae]): a native forb candidate for inclusion in Great Basin greenstrips

Inula helenium and Grindelia squarrosa as a source of compounds with anti-inflammatory activity in human neutrophils and cultured human respiratory epithelium.

During the epidemic season, over 90% of acute wheezing disease is associated with bronchial inflammation. Both neutrophil- and eosinophil-mediated inflammation have been involved in the pathophysiology of acute bronchitis, but neutrophil cell recruitment has been shown to be dominant. The ongoing inflammation increases the chemotaxis of neutrophils to inflamed site providing to their overaccumulation. The pharmacological reduction of neutrophil migration can be limited by suppression of major chemo-attractants and cytokines (IL-8, IL-1β and TNF-α) release and downregulation of adhesive molecules. During a screening of plants traditionally used in respiratory tracts diseases (e.g. cough, rhinitis, bronchitis, throat infection, fever, influenza) in Europe, we have selected roots of Inula helenium and aerial parts of Grindelia squarrosa as a potential source of compounds limiting neutrophil migration. The effect on IL-8, IL-1β and TNF-α release by neutrophils and respiratory epithelium cell line (A549) was measured by enzyme-linked immunosorbent assay (ELISA). The surface expression of adhesive molecules was analyzed with flow cytometry, and the neutrophil attachment to the epithelial cells was assessed fluorimetrically. We confirmed the ability of selected extracts and compounds to suppress neutrophil binding to the epithelium surface via downregulation of β2 integrin. Alantolactone and grindelic acid have shown significant suppression of IL-8, TNF-α and IL-1β release comparable with budesonide, used as a positive control. The present study demonstrated that Inula helenium and Grindelia squarrosa, which have been traditionally used in Europe as medicinal plants, are a valuable source of active compounds with anti-inflammatory activity. Our observations justify the traditional use of I.helenium and G.squarrosa for a treatment of inflammation-based diseases in respiratory tract.

Upgrading Biocrude of Grindelia Squarrosa to Jet Fuel Precursors by Aqueous Phase Hydrodeoxygenation

AbstractBio‐jet fuel is increasingly attracting attention in attempts to reduce the environmental impacts of aviation fuels. Feedstocks like camelina, jatropha and algae have been extensively studied, and exhibit fair performance in producing low‐density hydrocarbon biofuels, mainly from triglyceride lipids. Grindelia squarrosa is a promising feedstock since the primary diterpenoid, grindelic acid with the branched tricyclic structure, is the major component in its biocrude. Herein, a heterogeneous bi‐functional catalyst, palladium with the reductive properties supported on tungstate zirconia with acidic properties and good stability in hydrothermal media, was used for the conversion of Grindelia squarrosa biocrude to potential bio‐jet fuels. Different solid acid catalyst supports and a variety of reaction conditions, such as temperature, catalyst loading, hydrogen pressure, and reaction time, were systematically investigated. At the optimum conditions, the oxygen content deceased from 18.1 % in the Grindelia squarrosa biocrude feedstock to 5.6 % in the final product, and is ready for further industrial treatment. The upgrading method utilized in this work can produce jet fuel precursors for synthesizing high‐density cyclic hydrocarbons.

Production of High-Density Renewable Aviation Fuel from Arid Land Crop

Grindelia squarrosa biocrude is a promising feedstock for producing high-density cycloalkane fuels for high-performance aircraft due to the branched tricyclic nature of its primary diterpenoid component, grindelic acid. Herein we designed a novel biphasic tandem catalytic process (biTCP) for the conversion of Grindelia squarrosa biocrude into high-density aviation fuels with a superior carbon atom efficiency. The systematic experimental studies provided valuable insights into the effects of process conditions. The detailed speciation was carried out with the complementary chemical analysis techniques. Under the optimum conditions, a ∼90% carbon yield of aviation fuel components was produced from the Grindelia squarrosa biocrude. Multistep tandem reactions, including cyclic ether ring opening, dehydration, hydrogenation, and decarboxylation were carried out in the “one-pot” biTCP. The detailed catalytic reaction mechanism is discussed. A continuous process was designed integrating the extraction of biocrude and its conversion to dense jet fuels using biTCP. The techno-economic analysis has been performed, and in its current state, the proposed process is expected to deliver price-competitive high-density aviation fuel products.

Fast Pyrolysis of Opuntia ficus-indica (Prickly Pear) and Grindelia squarrosa (Gumweed)

Opuntia ficus-indica (prickly pear) and Grindelia squarrosa (gumweed) are two exceptionally drought tolerant plant species capable of growing in arid and semiarid environments. Additionally, they have unique cell wall structures. Prickly pear contains pectin and high levels of ash (16.1%) that is predominantly Ca and K. Gumweed has high levels of extractives that contain grindelic acid and monoterpenoids. The objective of this paper was to evaluate how these unique cell wall components alter the pyrolysis performance of prickly pear and gumweed. Using a tandem micropyrolyzer with GC-MS/FID/TCD, a detailed account of the product slate is given for products generated between 450 and 650 °C. Pyrolysis of prickly pear showed that the high levels of ash increase the amount of organics volatilized and shifted product pools, making it possible to generate up to 7.3% carbonyls vs 3.8% for Pinus taeda (loblolly pine) and 10.5% hydrocarbons vs 1.8% for pine depending on reaction conditions. Pyrolysis of gumweed sho...

Peculiarities of migration and accumulation of heavy metals in the system «ground-plant» by the example of the National natural park «Beloberezhye Svyatoslava»

Peculiarities of migration and accumulation of heavy metals in the system «ground-plant» by the example of the National natural park «Beloberezhye Svyatoslava»