Platanus Acerifolia Research Articles

Mapping of Biochemical Constituents in Platanus acerifolia Leaves By Analytical Techniques

Platanus acerifolia (Plataceae) is woody perennial tree, a native of Asia, Europe, and Eastern Mediterranean regions of the world. It is commonly cultivated and highly valued as an ornamental and medicinal tree. Its leaves as a natural waste is available in abudance, easy to obtain and cheap. In the present study, P. acerifolia leaves were obtained from Kocaeli region of Turkey at the autumn period. All of the specimens were dried in air before using analytical techniques. The leaves were analyzed by using X-ray diffraction (XRD), Attenuated Total internal Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR), Scanning Electro Microscopy- Enegy-Dispersive X-ray Spectroscopy (SEM-EDX). All analysis were performed for providing an accurate detection of the leaf molecular structure, crystalline phase, chemical compositions (organic or inorganic constituent), elemental index, morphology and microstructure. From X-ray diffraction pattern, crystaline phase and chemical compositions of the leaf specimens were identified as whewellite (C2CaO4.H2O), schertelite (Mg(NH4)2H2(PO4)24H2O), silicon oxide (SiO2), amide (C13H17N7O3), ester (C37H68O8), benzene (C28H40O10). According to ATR-FTIR analysis results, characteristic peak values of the leaf specimens were detected functional groups as (P-O), (C=O), (ClO), (C-O), (P-O-H), (C-H), (N-H), (O-C=O), (K-NO), (Ca-CO), (NH), (C=H), (N=O), (O-H), (CH), (NN), (Si-O-Si). SEM-EDX analysis showed the present of carbon, nitrogen, oxygen, magnesium, silicon, phosphor, chloride, potassium, and calcium in the leaf specimens. Morphology and microstructure of opened or closed stomas, fiber of leaf specimens were monitored. The chemical compositions, the functional groups and the elements are responsible for various medicinal properties of P. acerifolia leaves. Nanoparticles obtained from the leaves by using developed plant extract process can be used as biomaterial, biosorbent and nanomedicine against various plant, human, and animal diseases or pathogens.

Microfluidic system for high-throughput immunoglobulin-E analysis from clinical serum samples

Rapid and high-throughput analytical techniques for IgE that requires a small serum amount are very important, especially for pediatric patients. In these patients, blood is collected from veins, which is painful compared to fingertip blood collection. Herein, a novel microfluidic system capable of high-throughput parallel analyses of allergen-specific IgE from small amounts of patient serum was successfully developed. A six-plex immunoassay was constructed within a microfluidic chip, and the entire system was validated using samples from clinical patients. Major antigens from house dust mite (Dermatophagoides farinae and Blomia tropicalis), cat (Felis domesticus), fungus (Cladosporium herbarum), ragweed (Humulus japonicas), and tree pollen (Platanus acerifolia) were used as analysis targets. Sample consumption decreased to <0.05 µL compared with the 480µL serum consumption by fluoroenzyme immunoassay (UniCAP system Pharmacia Diagnostics AB, Uppsala, Sweden), the 50 µL serum consumption by enzyme-linked immune sorbent assay (ELISA), or the 1.5 µL serum consumption by conventional protein chip analysis. Analysis duration, reagent cost, and total cost for each measurement were also considerably decreased. The assay showed good accuracy and sensitivity toward the clinical samples. A significant correlation of allergen-specific IgE levels was found among the microfluidic assay, UniCAP system, and ELISA.

Detoxification strategies and regulation of oxygen production and flowering of Platanus acerifolia under lead (Pb) stress by transcriptome analysis.

Toxic metal pollution is a major environmental problem that has received wide attention. Platanus acerifolia (London plane tree) is an important greening tree species that can adapt to environmental pollution. The genetic basis and molecular mechanisms associated with the ability of P. acerifolia to respond lead (Pb) stress have not been reported so far. In this study, 16,246 unigenes differentially expressed unigenes that were obtained from P. acerifolia under Pb stress using next-generation sequencing. Essential pathways such as photosynthesis, and gibberellins and glutathione metabolism were enriched among the differentially expressed unigenes. Furthermore, many important unigenes, including antioxidant enzymes, plants chelate compounds, and metal transporters involved in defense and detoxification mechanisms, were differentially expressed in response to Pb stress. The unigenes encoding the oxygen-evolving enhancer Psb and OEE protein families were downregulated in Pb-stressed plants, implying that oxygen production might decrease in plants under Pb stress. The relationship between gibberellin and P. acerifolia flowering is also discussed. The information and new insights obtained in this study will contribute to further investigations into the molecular regulation mechanisms of Pb accumulation and tolerance in greening tree species.

Identification and functional analysis of microRNAs and their targets in Platanus acerifolia under lead (Pb) stress.

MicroRNAs (miRNAs) play important regulatory roles in development and stress responses in plants. Lead (Pb) is a non-essential element that is highly toxic to living organisms. Platanus acerifolia is grown as a street tree in cities throughout temperate regions for its importance in improving the urban ecological environment. MiRNAs that respond to abiotic stresses have been identified in plants; however, until now, the influence of Pb stress on P. acerifolia miRNAs has not been reported. To identify miRNAs and predict their target genes under Pb stress, two small RNA and two degradome libraries were constructed from Pb-treated and Pb-free leaves of P. acerifolia seedlings. After sequencing, 55 known miRNAs and 129 novel miRNAs were obtained, and 104 target genes for the miRNAs were identified by degradome sequencing. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were performed to predict the functions of the targets. The expressions of eight differentially expressed miRNAs were validated by quantitative real-time polymerase chain reaction (qRT-PCR). This is the first report about P. acerifolia miRNAs and their target genes under Pb stress. This study has provided data for further research into molecular mechanisms involved in resistance of P. acerifolia to Pb stress.

Ranking the suitability of common urban tree species for controlling PM2.5 pollution

Pollution caused by particles with aerodynamic diameters less than 2.5 μm (PM2.5) is now a major environmental problem in many Asian cities. Planting more trees has been suggested as an unconventional approach to alleviate the problem. In this study, we developed a ranking approach to evaluate the PM2.5 removal efficiency, negative impacts on air quality, and the suitability to urban environments of commonly occurring urban tree species. The results showed that the most frequently occurring tree species in global cities were not the best performers in removing PM2.5. Among the ten most frequently occurring tree species, only London plane (Platanus acerifolia (Aiton) Wild.), silver maple (Acer saccharinum L.) and honey locust (Gleditsia triacanthos L.) were ranked above average. However, there is great potential for improving the removal of PM2.5 from urban air by using species that have high PM2.5 removal efficiency, especially conifer species. Use of conifer species requires choosing the correct gender and matching trees with appropriate sites. The results from this study can assist environmental management agencies in the selection of tree species for urban greening projects focusing on PM2.5 control.

Sycamore Tree Lace Bug (Corythucha ciliataSay) (Hemiptera: Tingidae) Reaches Africa

In February 2014 colonies of a large and conspicuous lacebug (Fig. 1A) were collected from the undersides of the leaves of London plane trees (Platanus x acerifolia) in the suburb of Newlands, Cape Town, South Africa. Infected leaves could easily be identified by their characteristic bronzed appearance (Fig. 1B). The lace bugs were subsequently identified as Corythucha ciliata (Say) using keys to North American Corythucha species (Mead 1989) and economically important tingids of the world (Stonedahl et al. 1992). Corythucha species have high host-specificity, whilst C. ciliata is the only lace bug known to feed on Platanus species (sycamores) - this association is thus considered to be diagnostic for the species (CABI 2014). C. ciliata has a broad native range across the eastern parts of North America and Canada, where it is largely monophagous on Platanus (sycamore) trees, with P. occidentalis being its main host. However, it also occurs on Platanus hybrids, and in invasive parts of its range feeds on P. orientalis and P. x acerifolia (the hybrid between P. occidentalis and P. orientalis (CABI 1984).

Subterranean termites in urban forestry: tree preference and management.

Urban tree deterioration is a common problem all over the world. Inappropriate plant species choice and inadequate planting may lead to micro and macro organism attacks, such as pests and diseases. Subterranean termite damage is common and may promote tree falls. In order to help urban forestry planning, this work was carried out for 9 years on 1477 street trees in a neighborhood in the city of São Paulo, Brazil. Plants were identified to species, grouped as native, exotic plants, and palm trees, and their measures of circumference at breast height (CBH) were taken, in order to evaluate if subterranean termite damages are related to tree size and plant group. Four subterranean termite species were identified infesting up to 27% of the plants, with Coptotermes gestroi (Wasmann) being the most common. Palm trees were not damaged by subterranean termites, while native plants are the most susceptible, especially Caesalpinia pluviosa var. peltophoroides (Fabaceae). Among the native plants monitored C. pluviosa var. peltophoroides, Caesalpinia ferrea var. leiostachya, Erythrina speciosa, Piptadenia gonoacantha (Fabaceae), Gochnatia polymorpha (Asteraceae), Tibouchina granulosa (Melastomataceae), and Handroanthus spp. (Bignoniaceae), the latter was the least damaged. Exotic plants were also susceptible with the exception of Lagerstroemia indica (Lythraceae) and Platanus acerifolia (Platanaceae). Correlation analysis showed that the higher the CBH value, the higher the percentage of internal damage by C. gestroi. Infested trees were treated with imidacloprid and thiamethoxam, and subterranean termites were effectively controlled during the 9-year study.

First Report of Powdery Mildew of Platanus × acerifolia and P. occidentalis Caused by Erysiphe platani in Greece.

London planetrees (Platanus × acerifolia, syn. P. × hispanica), American sycamores (P. occidentalis), and oriental planes (P. orientalis) are widely planted as urban shade trees throughout Greece and many other countries. In June 2012, typical symptoms of a powdery mildew were detected on all sycamores (10 trees) along a central avenue of Heraklion (Crete, Greece), with the disease affecting approximately 80% of the leaves of all infected trees. In August 2013, similar symptoms were observed on 20% of the leaves of all three London planes in a small grove in the Vrysses area of Lasithi (Crete, Greece). In both cases, the disease was severe, with white superficial colonies developing amphigenously on leaves, twigs, floral peduncles, inflorescences, and fruits. The colonies were initially distinct and circular but gradually enlarged and often coalesced to cover the entire leaf blade. Young leaves appeared curled and chlorotic, occasionally leading to defoliation. For the morphological description of the pathogen, samples from seven infected P. occidentalis and three P. × acerifolia trees were microscopically characterized. In all samples, the pathogen's mycelium was branched, septate, and hyaline, with lobed appressoria; conidiophores were erect, cylindrical, unbranched, and consisted of three to four (to five) cells; and conidia were single or in short chains (two to four), ellipsoid or doliiform, with a truncated base and rounded apex. Their dimensions were 24.3 to 48.6 × 15.8 to 27.9 μm (averaging 39.2 × 21.2 μm; n = 100), and their surfaces appeared reticulate. The teleomorph was never observed. Total fungal DNA was extracted from conidia harvested from affected leaves of one infected plant of each of P. occidentalis and P. × acerifolia planes, and the ITS1-5.8S-ITS2 region was PCR-amplified with universal primers 18S-ITS1 and 28S-ITS2 (2) and sequenced (GenBank Accession Nos. KM068123 and KM068124, respectively). A BLASTn search of GenBank revealed 100% identity of both samples to Erysiphe platani strains described on P. orientalis in Greece (JQ365943) and P. occidentalis in Brazil (KF499270). Based on the morphological and molecular analyses, the pathogen was identified as E. platani (Howe) U. Braun & S. Takam. (formerly known as Microsphaera platani Howe) (1). To prove pathogenicity and fulfill Koch's postulates, 10 1-year-old seedlings of each of P. occidentalis and P. × acerifolia hosts were artificially inoculated with conidia obtained from naturally infected plants of the corresponding species, with two methods: (i) five plants of each host were dusted with conidia from diseased leaves, and (ii) the remaining five seedlings of each plane were sprayed with a conidial suspension of the fungus (107 conidia ml-1), while five additional control plants of each species were treated only with sterile distilled water. All plants were maintained in the greenhouse at 25 ± 3°C, with 90% humidity. Powdery mildew symptoms, which appeared 9 and 15 days after inoculation on all dusted and sprayed plants, respectively, were similar to those observed on naturally infected trees, whereas no symptoms were observed on control plants. Although E. platani is known to infect plane species in several parts of the world (1), including oriental planes (P. orientalis and P. orientalis var. cretica) in Greece (3), this is the first report of E. platani causing disease of P. occidentalis and P. × acerifolia in Greece, underlining the need for appropriate control measures to prevent significant losses to the local ornamental industry.

Cambial domain pattern in the root and root collar of Plalanus

The grain pattern in wood and the pattern of orientation of ray splitting and uniting were studied in roots and root collar of &lt;i&gt;Platanus acerifolia&lt;/i&gt;. In roots the interlocked-grain wood was observed as in the stem. An analysis of changes in xylem rays indicates that the cambial domain pattern exists and migrates upward there. In the root collar the grain in wood was straight although cambial domains were noted too. The domain pattern is characterized by relatively wide variations of the domain length and by pulsation: expanding some domains and reducing others so that it does not become manifest in the grain.

A disease of canker occured on Platanus acerifolia

A disease of canker occured on <i>Platanus acerifolia</I>

First Report of Powdery Mildew Caused by Erysiphe platani on Platanus × acerifolia in Rio Grande do Sul, Brazil.

Platanus × acerifolia (Aiton) Willd. (London planetree) is a tree commonly used as an ornamental and in the furniture industry. In the summer of 2013, powdery mildew was observed on shoots of P. × acerifolia plants in the cities of Pelotas and Canela (State of Rio Grande do Sul, Brazil). Voucher specimens (n = 2) were deposited in the Phytopathological Museum Manoel Alves Oliveira at Federal University of Pelotas. Dense white powdery masses of conidia and mycelium were observed on leaves (abaxial and adaxial surfaces), petioles, and young stems. Leaves with high disease severities (≥70%) were deformed with curved edges to the adaxial side, and they often died. Mycelia were superficial with lobed appressoria. Conidiophores were straight, sometimes curved at the base, unbranched, cylindrical, 98 to 236 μm long (137.3 ± 41.2 μm) and composed of a cylindrical foot cell 49 to 102 μm long (66.9 ± 19.5 μm) and 4.4 to 6.4 μm wide (5.3 ± 0.8 μm) followed by two to four cells. Conidia were produced singly or in short chains (two to three), without distinct fibrosin bodies, ellipsoid to ovoid and measuring 24 to 37 μm long (29.5 ± 3.2 μm) and 12 to 19 μm wide (15.2 ± 1.4 μm), often with a wrinkled appearance. Primary conidia had truncate bases and rounded apex while both base and apex were truncated in secondary conidia. Germ tubes were produced apically (pseudoidium type). Chasmothecia were not observed. Genomic DNA was used to amplify the internal transcribed spacer (ITS) region using the ITS1 and ITS4 primers. The resulting sequence (602 bp) was deposited (Accession No. KF499270) in GenBank. BLASTn searches revealed similarity of 100 and 99% with Erysiphe platani from P. orientalis L. (Accession No. JQ365943.1) and P. occidentalis L. (Accession No. JX997805.1), respectively. Phylogenetic analysis placed our sequence in a clade (99% bootstrap support) which included only other E. plantani sequences. In short, morphological and molecular approaches allowed us to identify the infecting fungus as E. platani. For Koch's postulates, 10 detached leaves were inoculated (10 to 15 conidia cm2) on their adaxial surface using an eyelash brush. Non-inoculated leaves served as control. All leaves were kept inside trays with petiole immersed in humidified cotton and maintained at 25 ± 1°C. Symptoms identical to those of the original leaves were observed 6 to 8 days after inoculation, whereas the control leaves remained symptomless. Although E. platani has been previously reported on P. × acerifolia in the city of Poços de Calda, state of Minas Gerais, Brazil (1) and on P. occidentalis in Korea (2), to our knowledge, this is the first record of E. platani on P. × acerifolia in Rio Grande do Sul, Brazil.

Naturally derived porous carbon with selective metal- and/or nitrogen-doping for efficient CO2 capture and oxygen reduction

A low-cost, high-performance “green carbon”, derived from London plane leaves, exhibits excellent sorption capacity for CO2 capture and electro-catalytic capability for oxygen reduction, due to naturally doped nitrogen and metallic elements inherited from biomass.

Investigation of antimalarial activity, cytotoxicity and action mechanism of piperazine derivatives of betulinic acid.

To semisynthesise piperazine derivatives of betulinic acid to evaluate antimalarial activity, cytotoxicity and action mechanism. The new derivatives were evaluated against the CQ-sensitive Plasmodium falciparum 3D7 strain by flow cytometry (FC) using YOYO-1 as stain. Cytotoxicity of 4a and 4b was performed with HEK293T cells for 24 and 48 h by MTT assay. The capability of compound 4a to modulate Ca(2+) in the trophozoite stage was investigated. The trophozoites were stained with Fluo4-AM and analysed by spectrofluorimetry. Effect on mitochondrial membrane potential (ΔΨm) was tested for 4a by FC with DiOC6 (3) as stain. For β-haematin assay, 4a was incubated for 24 h with reagents such as haemin, and the fluorescence was measured by FlexStation at an absorbance of 405 nm. Antimalarial activity of 4a and 4b was IC50 = 1 and 4 μm, respectively. Compound 4a displayed cytotoxicity with IC50 = 69 and 29 μm for 24 and 48 h, respectively, and 4b was not cytotoxic at the tested concentrations. Addition of 4a leads to an increase in cytosolic Ca(2+) . We have measured ΔΨm after treating parasites with the compound. Data on Figure 4a show that mitochondria were not affected. The action mechanism for 4a, inhibition of β-haematin formation (17%), was lower than CQ treatment (83%; IC50 = 3 mm). Compound 4a showed excellent antimalarial activity, and its action mechanism is involved in Ca(2+) pathway(s).

Effects of Plant Material as Carbon Sources on TN Removal Efficiency and N2O Flux in Vertical-Flow-Constructed Wetlands

A nitrate-dominant synthetic wastewater simulating slightly polluted water with low C/N and poor biochemical availability was treated in lab-scale vertical-flow (VF)-constructed wetlands, which had Phragmites australis planted with different types of external carbon sources: Platanus acerifolia leaf litters, P. australis litters, glucose and a blank test with no external carbon sources. A comparison of the TN removal and N2O flux performances among the four wetland reactors indicated higher TN removal efficiencies and N2O release fluxes in the VF wetland columns with external carbon sources, as measured by the percentage removal of TN (P. acerifolia leaf litters 82.49 %, P. australis litters 70.55 %, glucose 62.50 % and blank 46.45 %) and N2O flux (P. acerifolia leaf litters 2275.22 μg · m−2 · h−1, P. australis litters 1920.53 μg · m−2 · h−1, glucose 1598.57 μg · m−2 · h−1 and blank 1192.08 μg · m−2 · h−1). This was primarily because of an improved supply of organic carbon from the external carbon sources for heterotrophic denitrification. And, the nitrogen released from the decomposition of plant materials resulted in the N2O release fluxes to some extent. However, employing P. acerifolia leaf litters and P. australis litters as external carbon sources caused net increases in organics of the final effluent water. Overall, the results not only demonstrated the potential of using external plant carbon sources in VF wetlands to enhance the TN removal efficiency but also showed a risk of excessive organic release and greater N2O flux feedback to global warming. Hence, future studies are needed to optimise the quantity and method for adding external carbon sources to VF-constructed wetlands so that sufficient nitrate removal efficiency is achieved and the N2O flux and organic pollution are minimised.

Recovery of betulinic acid from plane tree (Platanus acerifolia L.)

Abstract Betulinic acid (3β, hydroxy-lup-20(29)-en-28-oic acid) is a bioactive triterpenic acid which was identified in various botanical sources and in considerable amounts in the bark of plane tree ( Platanus acerifolia L.). In this work, the recovery of betulinic acid from plane tree bark was studied using different liquid solvent based extraction methods, namely solid–liquid extraction (SLE), ultrasound assisted extraction (UAE) and pressurized liquid extraction (PLE). Furthermore, preliminary studies of the supercritical fluid extraction (SFE) of plane tree bark are also reported. The liquid solvent based extraction techniques (SLE, UAE and PLE) were carried out using ethanol and ethyl acetate, and produced a recovery of betulinic acid in the range 10–15 mg/g of bark, with concentrations around 25–35% mass. A betulinic acid enrichment in the ethanolic extracts was possible by means of a simple precipitation step adding water. The precipitate contained 42–46% mass of betulinic acid and high recovery (>95%). Increasing the extraction temperature, by means of the PLE assays, has not resulted in an improvement of betulinic acid recovery. The preliminary SFE assays produced lower recoveries of betulinic acid (0.5–8 mg/g) with respect to liquid extraction. The addition of ethanol as cosolvent produced a significant improvement of both betulinic acid recovery and concentration in the SFE extract.

Isolation and handedness of helical coiled cellulosic thickenings from plant petiole tracheary elements

Leaf stalks (petioles) are critical compo- nents of the vascular system that conducts water from the roots to the photosynthetic apparatus of most green plants. Helical coiled cellulosic microfibrils that reinforce the tracheary elements in plant leaf petioles were isolated by a gentle treatment with alkali and acid chlorite from celery and from a number of tree species, including sugar maple, London plane, horse chestnut, tulip tree, paulownia and ginko. Analysis of the hydrolysate of celery coils gave glucose as the main product, but significant quantities of xylose and other sugars were also detected. Polarized light microscopy was used to determine the location, dimensions and handedness of the coils. The coils were made up of single or multiple parallel strands in contact, ranging up to 35 lm in diameter and several cm in length. The strand structure was chiral; significantly, only left- handed helices were observed. An attempt is made to rationalize the left-handed structure by comparison with the spontaneous handedness observed in vitro for cellulose nanocrystals suspensions. The ubiquitous presence of coiled thickenings in petiole vascular elements indicates their importance in plant functions.

ChemInform Abstract: Polyphenols from Platanus acerifolia Buds. Part 11. Further Prenylated Flavonols from Platanus acerifolia′s Unripe Buds.

ChemInformVolume 45, Issue 31 Natural Products ChemInform Abstract: Polyphenols from Platanus acerifolia Buds. Part 11. Further Prenylated Flavonols from Platanus acerifolia′s Unripe Buds. Mourad Kaouadji, Mourad Kaouadji Lab. Pharmacogn., Fac. Pharm., F-87025 Limoges, Fr.Search for more papers by this author Mourad Kaouadji, Mourad Kaouadji Lab. Pharmacogn., Fac. Pharm., F-87025 Limoges, Fr.Search for more papers by this author First published: 17 July 2014 https://doi.org/10.1002/chin.201431207Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume45, Issue31August 5, 2014 RelatedInformation

Biogenic volatile organic compound emissions from nine tree species used in an urban tree-planting program

Abstract The biogenic volatile organic compound (BVOC) emissions of nine urban tree species were studied to assess the air quality impacts from planting a large quantity of these trees in the City and County of Denver, Colorado, through the Mile High Million tree-planting initiative. The deciduous tree species studied were Sugar maple, Ohio buckeye, northern hackberry, Turkish hazelnut, London planetree, American basswood, Littleleaf linden, Valley Forge elm, and Japanese zelkova. These tree species were selected using the i-Tree Species Selector ( itreetools.org ). BVOC emissions from the selected tree species were investigated to evaluate the Species Selector data under the Colorado climate and environmental growing conditions. Individual tree species were subjected to branch enclosure experiments in which foliar emissions of BVOC were collected onto solid adsorbent cartridges. The cartridge samples were analyzed for monoterpenes (MT), sesquiterpenes (SQT), and other C 10 –C 15 BVOC using thermal desorption-gas chromatography–flame ionization detection/mass spectroscopy (GC–FID/MS). Individual compounds and their emission rates (ER) were identified. MT were observed in all tree species, exhibiting the following total MT basal emission rates (BER; with a 1− σ lower bound, upper bound uncertainty window): Sugar maple, 0.07 (0.02, 0.11) μg g −1 h −1 ; London planetree, 0.15 (0.02, 0.27) μg g −1 h −1 ; northern hackberry, 0.33 (0.09, 0.57) μg g −1 h −1 ; Japanese zelkova, 0.42 (0.26, 0.58) μg g −1 h −1 ; Littleleaf linden, 0.71 (0.33, 1.09) μg g −1 h −1 ; Valley Forge elm, 0.96 (0.01, 1.92) μg g −1 h −1 ; Turkish hazelnut, 1.30 (0.32, 2.23) μg g −1 h −1 ; American basswood, 1.50 (0.40, 2.70) μg g −1 h −1 ; and Ohio buckeye, 6.61 (1.76, 11.47) μg g −1 h −1 . SQT emissions were seen in five tree species with total SQT BER of: London planetree, 0.11 (0.01, 0.20) μg g −1 h −1 ; Japanese zelkova, 0.11 (0.05, 0.16) μg g −1 h −1 ; Littleleaf linden, 0.13 (0.06, 0.21) μg g −1 h −1 ; northern hackberry, 0.20 (0.11, 0.30) μg g −1 h −1 ; and Ohio buckeye, 0.44 (0.06, 0.83) μg g −1 h −1 . The following trees exhibited emissions of other C 10 –C 15 volatile organic compounds (VOC): Littleleaf linden, 0.15 (0.10, 0.20) μg g −1 h −1 ; Ohio buckeye, 0.39 (0.14, 0.65) μg g −1 h −1 ; and Turkish hazelnut, 0.72 (0.49, 0.95) μg g −1 h −1 . All tree species studied in this experiment were confirmed to be low isoprene emitters. Compared to many other potential urban tree species, the selected trees can be considered low to moderate BVOC emitters under Colorado growing conditions, with total emission rates one-tenth to one-hundredth the rates of potential high-BVOC emitting trees. The emissions data were used to estimate the impact of this targeted tree planting on the urban BVOC flux and atmospheric VOC burden. Selecting the low-emitting tree species over known high BVOC emitters is equivalent to avoiding VOC emissions from nearly 500,000 cars from the inner city traffic.

Effects of two contrasting canopy manipulations on growth and water use of London plane (Platanus x acerifolia) trees

Two contrasting canopy manipulations were compared to unpruned controls on London plane trees, to determine the effects on canopy regrowth, soil and leaf water relations. ‘Canopy reduction’, was achieved by removing the outer 30 % length of all major branches and ‘canopy thinning’, by removing 30 % of lateral branches arising from major branches. Total canopy leaf areas recovered within two and three years of pruning for the canopy-thinned and reduced trees respectively. Canopy reduction increased mean leaf size, nitrogen concentration, canopy leaf area density and conserved soil moisture for up to 3 years, whereas canopy thinning had no effects. Another experiment compared more severe canopy reduction to unpruned trees. This produced a similar growth response to the previous experiment, but soil moisture was conserved nearer to the trunk. Analysis of 13C and 18O signals along with leaf water relations and soil moisture data suggested that lower boundary layer conductance within the canopy-reduced trees restricted tree water use, whereas for the canopy-thinned trees the opposite occurred. Only canopy reduction conserved soil moisture and this was due to a combination of reduced total canopy leaf area and structural changes in canopy architecture.

Chemical Constituents with Immunological Activities from the Barks of Platanus acerifolia

Platanus acerifolia (Aiton) Willd. (Platanaceae) is a hybrid of P. orientalis and P. occidentalis. P. acerifolia is highly resistant to powdery mildew and atmospheric contamination, so it is often used for landscaping and street planting. P. acerifolia was also used to treat toothache, dysentery and diarrhea in folk medicine and has rich resources. Studies have indicated that P. acerifolia consists mainly of the chemical constituents of flavonoids, triterpenes, tannins, and long-chain fatty compounds and possesses antibacterial, anti-HIV, antitumor, and uncoupling activity [1–4]. The 95% alcohol extract of the deciduous barks of P. acerifolia was separated by column chromatography on silica gel to yield compounds 1–6, which were individually identified as 3-acetylbetulinic aldehyde (1), betulonic acid (2), betulinic acid (3), daucosterol (4), 3,4,5-trimethoxyphenyl-O-D-glucopyranoside (5), and 3,4,5-trimethoxyphenyl-O-Dglucopyranoside-6 -sulfate sodium (6) by comparison of their spectral data to those reported in the literature [5, 6]. Compound 6 was obtained as a colorless granular crystalline powder. Its molecular formula was established as C15H21O12SNa by HR-ESI-MS at m/z 425.0759 [M – Na]– and 471.0543 [M + Na]+. Its 1H and 13C NMR spectra were typical of a glycoside of 3,4,5-trimethoxyphenol. The 13C NMR spectral data of the sugar moiety of 6 were consistent with those of glucose, except that the chemical shift of C-6 of 6 was shifted downfield by 5.0 ppm, which suggested compound 6 was the 6 -O-substituted glucopyranoside. The IR spectrum of 6 showed intense absorption at 1259 cm–1 and 814 cm–1, attributed to the stretching of the S=O bond and C–O–S bonds on the sulfate ester, and acid hydrolytic reaction gave sulfates (white precipitate with BaCl2), which indicated 6 is a glucosidal sulfate ester. 2D NMR including HMQC and HMBC experiments allowed us to assign all the proton and carbon signals of 6. 1H NMR (500 MHz, DMSO-d6, , ppm, J/Hz): 6.38 (s, H-2, 6), 3.75 (6H, s, CH3O-3, 5), 3.59 (3H, s, CH3O-4), 4.72 (d, J = 7.5, H-1 ), 3.21 (m, H-2 ), 3.23 (m, H-3 ), 3.06 (m, H-4 ), 3.53 (m, H-5 ), 4.15 (m, H-6 a), 3.68 (m, H-6 b), 5.23 (d, J = 5.0, 2 -OH), 5.07 (d, J = 4.5, 3 -OH), 5.10 (d, J = 5.5, 4 -OH). 13C NMR (125 MHz, DMSO-d6, , ppm): 154.2 (C-1), 94.5 (C-2, 6), 153.3 (C-3, 5), 132.6 (C-4), 101.3 (C-1 ), 73.4 (C-2 ), 76.7 (C-3 ), 70.5 (C-4 ), 75.1 (C-5 ), 66.1 (C-6 ). Thus, the structure of compound 6 was determined as 3,4,5-methoxyphenol-1-O-Dglucopyranoside-6 -sulfate sodium. Phenol glycoside and sulfate occur freely in Adiantum species of the family Adiantaceae [7], but this is the first report of their occurrence in the family Platanaceae.