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Introduced species lists provide essential background information for biological invasions research and management. The compilation of these lists is, however, prone to a variety of errors. We highlight the frequency and consequences of such errors using introduced Melaleuca (sensu lato, including Callistemon) species in South Africa as a case study. We examined 111 herbarium specimens from South Africa and noted the categories and sub-categories of errors that occurred in identification. We also used information from herbarium specimens and distribution data collected in the field to determine whether a species was introduced, naturalized and invasive. We found that 72% of the specimens were not named correctly. These were due to human error (70%) (misidentification, and improved identifications) and species identification problems (30%) (synonyms arising from inclusion of Callistemon, and unresolved taxonomy). At least 36 Melaleuca species have been introduced to South Africa, and field observations indicate that ten of these have naturalized, including five that are invasive. While most of the errors likely have negligible impact on management, we highlight one case where incorrect identification lead to an inappropriate management approach and some instances of errors in published lists. Invasive species lists need to be carefully reviewed to minimise errors, and herbarium specimens supported by DNA identification are required where identification using morphological features is particularly challenging. [ABSTRACT FROM AUTHOR]

ABSTRACT Bottlebrush polymers have densely tethered side chains grafted to a linear polymer backbone, resulting in stretching of both the side chains and backbone. Prior studies have reported that the side chains are only weakly stretched while the backbone is highly elongated. Here, scaling laws for the bottlebrush backbone and side chains are determined through small-angle neutron scattering analysis of a systematic series of poly(lactic acid) bottlebrush polymers synthesized via a 'grafting-through' ring-opening polymerization. Scattering profiles are modeled with the empirical Guinier-Porod, rigid cylinder, and flexible cylinder models. Side chains are found to be only weakly stretched, with an end-to-end distance proportional to N0.55, while the overall bottlebrush increases in size proportional to N0.77. These results demonstrate that the bottlebrush backbone is not fully extended and that both side chains and backbone have significant conformational flexibility in solution. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 104-111 [ABSTRACT FROM AUTHOR]

In nature, allelopathic substances are likely to influence the germination of seeds. Callistemon viminalis, Tephrosia vogelii, Senna spectabilis, Cupressus lusitanica, and Polyscias fulva are found around some tomato culture fields in Cameroon. These plants may produce allelochemicals that can influence tomato seed germination and seedling characteristics. Methanol extracts and their fractions were prepared from leaves of these plants and tested on seed germination rate, shoot diameter, root and stem lengths, and vigor index of seedlings. The tested substances did not significantly (p > 0.05) affect the seed germination rate. Aqueous extracts of T. vogelii, C. lusitanica, and C. viminalis exerted the highest inhibition on seed germination while methanol extract, hexane, and ethyl acetate fractions of all the plants induced significant increases in diameters of seedlings. Aqueous extracts were effective on the stem length. All treatments generally reduced the root length. Methanol extracts induced significantly higher vigor indices (p < 0.05). [ABSTRACT FROM AUTHOR]

Callistiviminenes A-O, fifteen adducts of β-triketone with sesqui- or monoterpene, along with a known compound, were isolated from the fruits of Callistemon viminalis . Callistiviminenes A and B are β-triketone-coupled (−)-bicyclosequiphellandrene contained an oxaspiro[5.5]undecene unit, and callistiviminenes C-E are rare adducts of β-triketone and bicyclogermacrene. Their structures and absolute configurations were elucidated by spectroscopic and computational methods, as well as by single-crystal X-ray diffraction experiment. A plausible biosynthetic pathway to these compounds involves a hetero-Diels–Alder reaction. Callistiviminenes C and D exhibited inhibition against lipopolysaccharide-induced nitric oxide production in RAW 264.7 macrophages with IC 50 value of 20.3 μ M and 32.5 μ M, respectively. [ABSTRACT FROM AUTHOR]

Quantitative reconstructions of terrestrial climate are highly sought after but rare, particularly in Australia. Carbon isotope discrimination in plant leaves (Δleaf) is an established indicator of past hydroclimate because the fractionation of carbon isotopes during photosynthesis is strongly influenced by water stress. Leaves of the evergreen tree Melaleuca quinquenervia have been recovered from the sediments of some perched lakes on North Stradbroke and Fraser Islands, south-east Queensland, eastern Australia. Here, we examine the potential for using M. quinquenervia ∆leaf as a tracer of past rainfall by analysing carbon isotope ratios ( δ13C) of modern leaves. We firstly assess Δleaf variation at the leaf and stand scale and find no systematic pattern within leaves or between leaves due to their position on the tree. We then examine the relationships between climate and Δleaf for a 11-year time series of leaves collected in a litter tray. M. quinquenervia retains its leaves for 1-4 years; thus, cumulative average climate data are used. There is a significant relationship between annual mean ∆leaf and mean annual rainfall of the hydrological year for 1-4 years (i.e. 365-1460 days) prior to leaf fall ( r2 = 0.64, P = 0.003, n = 11). This relationship is marginally improved by accounting for the effect of pCO2 on discrimination ( r2 = 0.67, P = 0.002, n = 11). The correlation between rainfall and Δleaf, and the natural distribution of Melaleuca quinquenervia around wetlands of eastern Australia, Papua New Guinea and New Caledonia offers significant potential to infer past rainfall on a wide range of spatial and temporal scales. [ABSTRACT FROM AUTHOR]

Resumen. Se hace el registro de tres nuevas enfermedades de importancia económica causadas por royas (Fungi, Pucciniales) en plantas de interés agronómico y ornamental en Colombia: sobre el género Allium, Puccinia allii; sobre Licania, Phakopsora tomentosa; y sobre Vaccinium, Thekopsora minima; y dos nuevos registros de hospedantes sobre Arachis pintoi, Puccinia arachidis Spegazzini var. arachidis; y sobre Callistemon citrinus, Puccinia psidii.Abstract. Three new diseases of economic impact caused by rusts (Fungi, Pucciniales) are registered in Colombia: on the genus Allium, Puccinia allii; on Licania, Phakopsora tomentosa; and on Vaccinium, Thekopsora minima; and two new plant host records on Arachis pintoi, Puccinia arachidis Spegazzini var. arachidis; and on Callistemon citrinus, Puccinia psidii.

This contribution reports for the first time on the synthesis and the main physical properties of single-phase pure α-Cr2O3nanoparticles synthesized by a facile, rapid and eco-friendly process usingCallistemon viminalisflower'sextractas an effective oxidizing/reducing agent. These crystalline nanoparticles exhibit a cubic-like platelet shape with sharp edges with an average particle diagonal size of ∼92.2 nm. The room temperature physical properties of these pure highly crystalline Eskolaite α-Cr2O3nanoparticles were carried out using complementary techniques such as high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectroscopy (EDS), XRD, FTIR-ATR, Raman and XPS. [ABSTRACT FROM PUBLISHER]

Green methods are powerful tools to minimize the use of toxic chemicals which are harmful to human beings as well as environment. The present study focuses on the use of aqueous extract ofCallistemon viminalis(bottlebrush) leaves for the synthesis of silver nanoparticles. The extract was used as a bioreductant and the polyphenols and flavanoids present in extract are responsible for the reduction of Ag+ions to zero valent silver nanoparticles. The effect of concentration of Ag+ions and cetyltrimethylammonium bromide on the nanoparticles was examined. On increasing the concentration of stabilizer, different morphological nano-couples are formed. The successful formation of silver nanoparticles was demonstrated by using ultraviolet–visible, transmission electron microscope and scanning electron microscope. Transmission electron microscope image analysis showed wide size distribution having dimer nanoparticles of hexagonal-triangular, square-triangular, spherical-triangular, spherical-spherical square-spherical morphologies. The antibacterial activity of extract reduced silver nanoparticles against four strains viz.Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniaeandSalmonella typhimuriumwas evaluated by calculation of minimum inhibitory concentration and minimum bactericidal concentration. The results show that synthesized nanoparticles could inhibit the growth of various bacteria tested. [ABSTRACT FROM AUTHOR]

Turkey Lake Germplasm of bottlebrush squirreltail (Elymus elymoides (Raf.) Swezey ssp. californicus (J.G. Smith) Barkworth [Poaceae]) was released by USDA Agricultural Research Service in 2015 as a selected class of pre-variety germplasm (natural track). This new plant material originates in Gooding County in southern Idaho's Snake River Plain. In replicated rangeland trials at 3 locations (Juab County, Utah; Sanpete County, Utah; White Pine County, Nevada), Turkey Lake Germplasm displayed substantially better establishment frequency than Toe Jam Creek Germplasm, a previous release of E. elymoides ssp. californicus (origin: Elko County, Nevada), as well as other released squirreltail plant materials. Comparative trials were also conducted in Cache County, Utah, and Bingham County, Idaho. [ABSTRACT FROM AUTHOR]

This study describes a novel biological route for the biosynthesis of silver oxide nanoparticles utilising the aqueous extract ofCallistemon lanceolatusD.C. leaves. Formation of silver oxide nanoparticles was confirmed by UV–visible spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscope–energy dispersive X-ray spectroscopy and X-ray diffraction spectroscopy analysis. The biologically synthesised silver oxide nanoparticles were found to be 3–30 nm in size with spherical and hexagonal shape by high-resolution transmission electron microscope analysis. Furthermore, the biogenic silver oxide nanoparticles demonstrated significant (p < 0.05) dose-dependent antioxidant activity in variousin vitroantioxidant methods. These particles also exhibited significant (p < 0.05) dose-dependent and time-dependent cytotoxic activity towards brine shrimp nauplii. Moreover, the reported method is a simple, cost-effective and eco-friendly approach for the synthesis of silver oxide nanoparticles with useful pharmacological properties. [ABSTRACT FROM AUTHOR]

The development of new antibiotics from new chemical entities is becoming more and more expensive, time-consuming, and compounded by emerging strains that are drug resistant. Alkaloids are plant secondary metabolites which have been shown to have potent pharmacological activities. The effect of alkaloids from Callistemon citrinus and Vernonia adoensis leaves on bacterial growth and efflux pump activity was evaluated on Staphylococcus aureus and Pseudomonas aeruginosa. At a concentration of 1.67 mg/mL, the alkaloids inhibited bacterial growth with comparable effects to ampicillin, a standard antibiotic. The alkaloids from C. citrinus were the most potent against S. aureus with an MIC of 0.0025 mg/mL and MBC of 0.835 mg/mL. It was shown that effects on P. aeruginosa by both plant alkaloids were bacteriostatic. P. aeruginosa was most susceptible to drug efflux pump inhibition by C. citrinus alkaloids which caused an accumulation of Rhodamine 6G of 121% compared to the control. Thus, C. citrinus alkaloids showed antibacterial activity as well as inhibiting ATP-dependent transport of compounds across the cell membrane. These alkaloids may serve as potential courses of compounds that can act as lead compounds for the development of plant-based antibacterials and/or their adjunct compounds. [ABSTRACT FROM AUTHOR]

The first triketone-phloroglucinol-monoterpene hybrids, callistrilones A and B (1 and 2), along with a postulated biosynthetic intermediate (3) were isolated from the leaves of Callistemon rigidus. Compounds 1 and 2 featured a new carbon skeleton with an unprecedented [1]benzofuro[2,3-a]xanthene or [1]benzofuro[3,2-b]xanthene pentacyclic ring system composed of three kinds of building blocks. Their structures and absolute configurations were elucidated by spectroscopic analysis, X-ray diffraction, and electronic circular dichroism (ECD) calculations. A plausible biogenetic pathway for the new compounds is also proposed. Compound 1 exhibited moderate antibacterial activity against Gram-positive bacteria including multiresistant strains. [ABSTRACT FROM AUTHOR]

Plants are important living organisms, particularly due to their ability to sustain life, and thus, the Earth and ecosystems. However, their ability to survive in any environment, requires plants - in general - to possess important structures to ward-off, or to be protected from, environmental pressures, such as predation and herbivory. In the bottlebrush and tomato plant types, the trichomes (or epidermal appendages) appear to be similar, yet the germination rate and overall plant morphology of both plant species, is greatly different. Although it's true that the germination rate and plant morphology between unrelated plant species are unrelated entities, the method of identifying plant structures among unrelated plants are - with certainty - the same. This paper, therefore, starts by looking at the differences of some features exhibited by the seeds of tomato and bottlebrush, followed by the differences (with emphasis on the trichomes), exhibited by the established plants of these two, obviously, different plant genera. [ABSTRACT FROM AUTHOR]

In this contribution, it is demonstrated for the first time in the literature the possibility of synthesizing Sm 2 O 3 nano-scaled particles as small as 〈ϕ particles 〉 ∼21.9 ± 5 nm using an entirely new green process. This latter is based on the usage of natural extract of the Callistemon viminalis as a strong chelating agent at room temperature. The selected area electron diffraction and the high resolution transmission electron microscopy confirmed the polycrystallinity of the Sm 2 O 3 nano-particles upon annealing at 500 °C. The complementary investigations by X-rays diffraction, infrared, Raman and X-rays photoelectron spectroscopy substantiated the single phase and the elemental purity of the Sm 2 O 3 nano-particles. [ABSTRACT FROM AUTHOR]

Callistemon citrinus (Myrtaceae) is a shrub native to Australia. Its flowers have been used as indigenous food among the aboriginal Australians. Numerous diseases, such as bacterial, fungal, viral and parasite infections have traditionally been treated with this plant. Gas chromatography–mass spectrometry (GC/MS) analyses of the flower and leaf extracts of C. citrinus revealed the presence of a major constituent, a phloroglucinol, 1-(2,6-dihydroxy-4-methoxyphenyl)-3-methylbutan-1-one ( 1 ) (up to 382.2 mg per 1 g of the flower extracts). Compound 1 was for the first time identified in this genus. This phloroglucinol exhibited potent antinociceptive and anti-inflammatory activities in a dose-dependent manner. In addition, this compound displayed strong in vitro antioxidant activity which could be easily connected with both anti-inflammatory and antinociceptive effects. Thus, compound 1 , as a plant constituent present in the diet of Aboriginal people, that helps with inflammation and pain, could have given them a better chance of survival in harsh conditions of the environment. [ABSTRACT FROM AUTHOR]

1,8-Cineole, limonene and α-terpineol are the major terpenes present in Callistemon citrinus. This study reports for the first time that terpenes attenuate the oxidative stress in rats fed with high-fat-sucrose diet (HFSD) via antioxidant and anti-inflammatory mechanisms. Thirty-six male Wistar rats were divided into six groups (n = 6). Control (fed standard food, HFSD (fed with 41.7% fat and 16.6% sucrose), HFSD + 1,8-cineole (0.88 mg/kg body weight), limonene (0.43 mg/kg body weight), α-terpineol (0.32 mg/kg body weight) and a mixture of the three terpenes, given daily by gavage for 15 weeks. Morphometric and biochemical parameters were taken. Paraoxonase (PON1), reduced glutathione (GSH), lipid peroxidation products malondialdehyde (MDA) and hydroxyalkenals (HNE), advanced oxidation protein products (AOPP) and pro-inflammatory cytokines were measured in liver homogenates. All terpenes showed a remarkable reduction in weight gain, fat deposition, serum glucose and, triacylglycerol levels. However, terpenes presented different effects on the hepatic cell and the oxidative biomarkers. Conversely, the three terpenes and the mixture showed the same positive effect on the tumor necrosis factor alpha (TNFα), interleukin-6 (IL-6), leptin and adiponectin levels. Finally, 1,8-cineole, limonene and α-terpineol demonstrate significant anti-inflammatory effects and differential effects on the oxidative stress, suggesting the importance of these terpenes in Callistemon citrinus activities. [Display omitted] • 1,8-cineole, limonene and α-terpineol attenuated the oxidative stress. • 1,8-cineole, limonene and α-terpineol showed a dyslipidemia effect. • 1,8-cineole, limonene and α-terpineol protected the hepatic cell. • 1,8-cineole, limonene and α-terpineol modulated the cytokines activities. [ABSTRACT FROM AUTHOR]

Coordinationpolymers (CPs) of metal ions are central to a largevariety of applications, such as catalysis and separations. Thesepolymers frequently occur as amorphous solids that segregate fromsolution. The structural aspects of this segregation remain elusivedue to the dearth of the spectroscopic techniques and computationalapproaches suitable for probing such systems. Therefore, there isa lacking of understanding of how the molecular building blocks giverise to the mesoscale architectures that characterize CP materials.In this study we revisit a CP phase formed in the extraction of trivalentlanthanide ions by diesters of the phosphoric acid, such as the bis(2-ethylhexyl)phosphoricacid (HDEHP). This is a well-known system with practical importancein strategic metals refining and nuclear fuel reprocessing. A CP phase,referred to as a “third phase”, has been known to formin these systems for half a century, yet the structure of the amorphoussolid is still a point of contention, illustrating the difficultiesfaced in characterizing such materials. In this study, we follow adeductive approach to solving the molecular structure of amorphousCP phases, using semiempirical calculations to set up an array ofphysically plausible models and then deploying a suite of experimentaltechniques, including optical, magnetic resonance, and X-ray spectroscopies,to consecutively eliminate all but one model. We demonstrate thatthe “third phase” consists of hexagonally packed linearchains in which the lanthanide ions are connected by three O–P–Obridges, with the modifying groups protruding outward, as in a bottlebrush.The tendency to yield linear polynuclear oligomers that is apparentin this system may also be present in other systems yielding the “thirdphase”, demonstrating how molecular geometry directs polymericassembly in hybrid materials. We show that the packing of bridgingmolecules is central to directing the structure of CP phases and thatby manipulating the steric requirements of ancillary groups one cancontrol the structure of the assembly. [ABSTRACT FROM AUTHOR]

Background: Plant-based traditional system of medicine continues to play an important role in healthcare. In order to find new potent source of bioactive molecules, we studied the cytotoxic activity of the essential oils from the flowers and leaves of Callistemon citrinus. This is the first report on anticancer potential of essential oils of C. citrinus. Methods: Cytotoxicity of essential oil was evaluated using sulfo-rhodamine B (SRB) assay against human lung carcinoma (A549), rat glioma (C-6), human colon cancer (Colo-205) and human cervical cancer (SiHa) cells. Apoptosis induction was evaluated by caspase-3/7 activity which was further confirmed by western blotting. Percentage cell apoptosis was determined by Annexin V based dead cell assay followed by DNA content as cell cycle analysis against A549 and C-6 cells. While 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was used to check the toxicity against normal human peripheral blood mononuclear cells (PBMCs), the immunomodulatory activity on mouse splenocytes was evaluated using SRB assay. Results: The GC and GC-MS analysis of these essential oils revealed high content of α-pinene (32.3%), limonene (13.1%) and α-terpineol (14.6%) in leaf sample, whereas the flower oil was dominated by 1,8-cineole (36.6%) followed by α-pinene (29.7%). The leaf oil contained higher amount of monoterpene hydrocarbons (52.1%) and sesquiterpenoids (14%) as compared to flower oil (44.6% and 1.2%, respectively). However, the flower oil was predominant in oxygenated monoterpenes (43.5%). Although both leaf and flower oils showed highest cytotoxicity on A549 cells (61.4%±5.0 and 66.7%±2.2, respectively), only 100 μg/mL flower oil was significantly active against C-6 cells (69.1%±3.1). Interestingly, no toxicity was recorded on normal cells. Conclusion: Higher concentration of 1,8-cineole and/or synergistic effect of the overall composition were probably responsible for the efficacy of flower and leaf oils against the tested cells. These oils may form potential source of natural anti-cancer compounds and play important role in human health. [ABSTRACT FROM AUTHOR]

The effect of water deficit, salinity and both applied simultaneously on several physiological and morphological parameters in the ornamental plant Callistemon laevis was studied to identify the tolerance mechanisms developed by this species to these sources of stress and to evaluate their adaptability to such conditions. C. laevis plants were grown in pots outdoors and subjected to four irrigation treatments lasting ten months: control (0.8 dS m −1 , 100% water holding capacity), water deficit (0.8 dS m −1 , 50% of the amount of water supplied in control), saline (4.0 dS m −1 , same amount of water supplied as control) and saline water deficit (4.0 dS m −1 , 50% of the water supplied in the control). Water and saline stress, when applied individually, led to a reduction of 12% and 39% of total biomass, respectively, while overall plant quality (leaf color and flowering) was unaffected. However, saline water deficit affected leaf color and flowering and induced an excessive decrease of growth (68%) due to leaf tissue dehydration and a high leaf Cl and Na concentration. Biomass partitioning depended not only on the amount of water applied, but also on the electrical conductivity of the water. Water stress induced active osmotic adjustment and decreased leaf tissue elasticity. Although both Na and Cl concentrations in the plant tissues increased with salinity, Cl entry through the roots was more restricted. In plants submitted to salinity individually, Na tended to remain in the roots and stems, and little reached the leaves. However, plants simultaneously submitted to water and saline stress were not able to retain this ion in the woody parts. The decrease in stomatal conductance and photosynthesis was more marked in the plants submitted to both stresses, the effect of which decreased photosynthesis, and this together with membrane damage delayed plant recovery. The results show that the combination of deficit irrigation and salinity in C. laevis is not recommended since it magnifies the adverse effects of either when applied individually. [ABSTRACT FROM AUTHOR]

Impervious surfaces can adversely alter the soil conditions encountered by tree roots in urban environments. However, these conditions may be rendered more suitable for tree growth by the use of permeable surfaces. This study assessed whether permeable pavements with varying depths (0, 100 or 300 mm) of underlying base layer affected the ecophysiological status of broad-leaf paperbark ( Melaleuca quinquenervia ) trees planted in sandy or clay soils. This study measured instantaneous leaf gas exchange, including photosynthesis ( A 1400 ), CO 2 concentration at the carboxylation site ( C i ), stomatal conductance ( g s ) and intrinsic water use efficiency (i WUE ), and assessed soil and leaf total nitrogen (TN) concentrations. This study also determined longer-term nitrogen cycling and water use efficiency by measuring nitrogen and carbon isotope compositions (δ 15 N and δ 13 C) of the soil and leaves. Each of these variables was then related to tree growth over the 18 months of the study. The study found that the different permeable pavement treatments often did not affect A 1400 , C i , g s or i WUE , and no significant correlation was found between these four variables and tree growth during the initial tree establishment phase when growth was slow. However, tree height and DBH growth during this phase did correlate with leaf δ 15 N in both soil types, suggesting that rapid nitrogen cycling was beneficial for initial growth. In contrast, trunk-diameter growth increments during the subsequent period of rapid growth were positively correlated with A 1400 , C i and g s , and negatively correlated with leaf δ 13 C, for trees in clay soil. Trees in clay soil were prone to waterlogging. However, installation of a base layer below the permeable pavement surface was found to reduce waterlogging, decrease leaf δ 13 C and increase tree growth. These results demonstrate that inclusion of a base layer is important for promoting tree growth when permeable pavements are installed over poorly draining soils such as clay. [ABSTRACT FROM AUTHOR]

We investigate the microstructure and linear viscoelasticity of model molecular bottlebrushes (BBs) using rheological and small-angle X-ray and neutron scattering measurements. Our polymers have short atactic polypropylene (aPP) side chains of molecular weight ranging from 119 g/mol to 259 g/mol and narrow molecular weight distribution (Mw/Mn 1.02-1.05). The side chain molecular weights are a small fraction of the entanglement molecular weight of the corresponding linear polymer (MeaPP= 7.05 kg/mol) and as such they are unentangled. The morphology of the aPP BBs is characterized as semiflexible thick chains with small side chain interdigitation. Their dynamic master curves obtained by time-temperature superposition reveal two sequential relaxation processes corresponding to the segmental relaxation and the relaxation of the BB backbone. Due to the short length of the side chains their fast relaxation could not be distinguished from the glassy relaxation. The fractional free volume is an increasing function of the side chain length (NSC). Therefore the glassy behavior of these polymers as well as their molecular friction and dynamic properties are influenced by their NSC values. The apparent flow activation energies are a decreasing function of NSC and their values explain the differences in zero-shear viscosity measured at different temperatures. [ABSTRACT FROM AUTHOR]

For a long period of time plants have been a valuable source of natural products for maintaining human health. According to W.H.O medicinal plants is one of the best source to obtain variety of drugs. The use of crude extracts of plant parts can be of great significance in therapeutic treatments. Present study deals with the phytochemical analysis and antibacterial activity of Madhuca longifolia, Callistemon citrinus and Schleichera triguga leaf and stem extracts against some pathogenic microorganisms viz. E. coli & P. aeruginosa. Extracts were prepared at three different concentrations (10,20 and 30%) in three different solvents with increasing (Chloroform < Methanol < Distilled water) by Soxhlet Extraction for analysis of bioactive compounds and antibacterial activity by Agar well diffusion method. The results for antibacterial activity revealed that the chloroform extract of Callistemon citrinus (leaf) when compared with antibiotic Erythromycin as standard was found to be the most potent inhibitor at concentration of 10,20 and 30% against E.coli and P.aeruginosa and phytochemical analysis also showed that methanolic extract of Bottle brush (Callistemon citrinus) leaf showed the presence of all seven groups of metabolites (alkaloids, flavonoids, cardiac glycosides, tannins, saponins, steroid and terpenoids). Only few of the phytochemicals (cardiac glycosides, terpenoid, steroid) were observed in aqueous extract of Leaf and Stem of Bottle brush (Callistemon citrinus), Mahua (Madhuca longifolia) and Kusum (Schleichera triguga). The study ascertains the value of plants which could be of considerable interest for the development of new drugs. [ABSTRACT FROM AUTHOR]

The conformational properties of bottle brushes with identical backbone lengths, grafting densities, and molecular masses of side arms, but different architectures of the arms, are studied via the Langevin dynamics method within the coarse-grained model. Volume interactions correspond to athermal-solvent conditions. The sizes and shapes of a whole macromolecule and its backbone and the mutual arrangement and deformation of the side arms are determined. The induced persistence length of the brush backbone, a property that characterizes the rigidifying effect of interactions between side arms, is estimated. It is shown that, for the considered model parameters, the induced persistence length is independent of the side-arm architecture, in agreement with predictions obtained earlier in the mean-field approximation. [ABSTRACT FROM AUTHOR]

Morphological changes in the gamete of female noble crayfish at four developmental stages were studied. Mature ovarian oocytes are enclosed by the first envelope that consists of two layers. Numerous pores are visible on the surface of the outer layer of this envelope and the inner layer contains bottlebrush-shaped objects. Three types of vesicles, including some that are highly and moderately electron-dense and some multi-layered, occur in the cortex of the oocyte. In freshly ovulated eggs, the pores in the outer layer are closed, and the bottlebrush-shaped objects in the inner layer are replaced by a spongiform electron-lucent matrix containing scattered electron-dense vesicles. One hour post-spawning, the first envelope, especially its inner layer, is condensed. The highly and moderately dense vesicles discharge their contents into the perivitelline space, where they combine and form a second envelope around the egg. Twenty-four hours post-ovulation, a second envelope is visible in the perivitelline space and the outer part of egg cortex. The highly and moderately electron-dense vesicles continue to release and combine contents to further construction of the second envelope after 24 h post-spawning. The egg attachment stalk is derived from the first envelope. The fertilization coat in the noble crayfish consists of first and second envelopes that are produced by the ovary and the cortical reaction, respectively. [ABSTRACT FROM AUTHOR]

Acer griseum is an endangered species in the world, while little is known about its genetic diversity. 27 polymorphic microsatellite loci from A . griseum were isolated and characterized by using a biotinylated (AG) 15 -enriched genomic library method. The polymorphisms of these markers were determined on 88 individuals. The number of alleles per locus ranged from 2 to 14. The observed heterozygosity, expected heterozygosity and the polymorphism information content ranged from 0.384 to 0.897, 0.000 to 0.934, 0.436 to 0.877, respectively. It was found that 15 loci deviated significantly from Hardy–Weinberg equilibrium after Bonferroni correction analysis and there was no significant genotypic linkage disequilibrium between pairs of loci. These microsatellites will be applied to further assessment of population genetic diversity and genetic resources conservation of A. griseum and other endangered maple species. [ABSTRACT FROM AUTHOR]

[Display omitted] Phytochemical investigation of Callistemon citrinus leaves resulted in the isolation of two new structurally unique callistrilone epimers named callistrilone Q (1) and epicallistrilone Q (2). Both epimers were found to exist in the form of equilibrium conformational isomers. The structural elucidation of the new compounds was achieved by HREIMS in addition to extensive 1D and 2D NMR spectroscopic analyses. The absolute configuration was determined using computational ECD and optical rotation calculations. Both isolated compounds displayed unprecedented preferential cytotoxic activities against PANC-1 human pancreatic cancer cells at the nanomolar level. These compounds also were found to inhibit PANC-1 cell migration under normal nutrient-rich conditions. Both compounds downregulated key proteins involved in the PI3K/Akt/mTOR signaling pathway. [ABSTRACT FROM AUTHOR]

Introduction: The genus Callistemon belongs to a group of medically significant plants which have found tremendous use in traditional medicine across the globe. They are reported for anti-cancer, neuroprotective, anti-inflammatory, antioxidant, anti-microbial, and many other significant medicinal attributes. However, the current use of this genus is limited mainly to ornamental and recreational purposes. Recent studies have reported several novel compounds like phloroglucinol derivatives, terpenes, phenolics, etc., from Callistemon spp., which have great medical significance. Further, there is a surge of recent studies reporting novel pharmacological properties of Callistemon. The number of review studies discussing the underlying molecular mechanism behind the pharmacological action of Callistemon is quite limited.Methods: The literature search for studies published from 1991 to 2021 using Google scholar and PubMed were selected. The review documented relevant literature focused on Callistemon spp exhibiting significant pharmacological effects.Results: This review deals with the pharmacological properties of Callistemon and the underlying molecular mechanism responsible for protective effect in several pathophysiological conditions. This study updated the current information regarding the medicinal importance of Callistemon spp. for research and the public community.Discussion and Conclusions: The preliminary studies, interrogating pharmacological properties of Callistemon spp., hold great promise and demand further research to decipher the mode of action. More and more research are needed in this direction to explore the full potential of the genus Callistemon as a medicinal herb. [ABSTRACT FROM AUTHOR]

Trees have been considered an effective means of assessing metal pollution in urban areas. In the present work, Callistemon citrininus and Acacia melanoxylon leaves were used to assess the air quality in urban parks surrounded by high vehicular traffic and in areas of industrial activity. The concentration of metals (Ca, K, Mg, Fe, Al, Mn, Ba, B, Zn, Cu and Pb) in the leaves was determined, and the results were compared between tree species and site types (parks and industrial). Ca, K, and Mg were found in higher concentrations than the other metals. Although significant differences in the concentration of metals between both tree species only reflected the composition of the plant itself, Acacia melanoxylon seems to display better performance as a biomonitor. According to the contamination factor (CF) results, most of the sites were classified as having suspected, slight or moderate contamination. Moreover, CF and principal component analysis indicated that Cu, Zn, Fe and Al were found to be the most contaminating metals at industrial sites, while Cu, Pb, Ba and Mn were the most contaminating metals at park sites. • Cu, Zn, Fe and Al are more associated with industrial areas. • People around parks are exposed to metal air pollution, mainly to Cu, Pb, Ba and Mn. • Acacia melanoxylon seems to have a better performance as a biomonitor than Callistemon citrinus. [ABSTRACT FROM AUTHOR]

Unique star-like polymeric architectures composed of bottlebrush arms and a molecular spoked wheel (MSW) core were prepared by atom transfer radical polymerization (ATRP). A hexahydroxy-functionalized MSW (MSW6-OH) was synthesized and converted into a six-fold ATRP initiator (MSW6-BR). Linear chain arms were grafted from MSW6-BR and subsequently functionalized with ATRP moieties to form six-arm macroinitiators. Grafting of side chains from the macroinitiators yielded four different star-shaped bottlebrushes with varying lengths of arms and side chains, i.e., (450-g-20) 6, (450-g-40) 6, (300-g-60) 6, and (300-g-150) 6. Gel permeation chromatography analysis and molecular imaging by atomic force microscopy confirmed the formation of well-defined macromolecules with narrow molecular weight distributions. Upon adsorption to an aqueous substrate, the bottlebrush arms underwent prompt dissociation from the MSW core, followed by scission of covalent bonds in the bottlebrush backbones. The preferential cleavage of the arms is attributed to strong steric repulsion between bottlebrushes at the MSW branching center. Star-shaped macroinitiators may undergo aggregation which can be prevented by sonication. [ABSTRACT FROM AUTHOR]

Hyphomycetous fungi Asteromyces cruciatus, a laboratory contaminant, Gyrothrix dichotoma from the fallen bottle brush branch and Wiesneriomyces javanicus from the deteriorating and decaying leaf of Holstonia scholaris a new host, were identified/ recorded for the first time from Rawalpindi, Pakistan. [ABSTRACT FROM AUTHOR]

The effect of saline stress on physiological and morphological parameters in Callistemon citrinus plants was studied to evaluate their adaptability to irrigation with saline water. C. citrinus plants, grown under greenhouse conditions, were subjected to two irrigation treatments lasting 56 weeks: control (0.8 dS·m−1) and saline (4 dS·m−1). The use of saline water in C. citrinus plants decreased aerial growth, increased the root/shoot ratio and improved the root system (increased root diameter and root density), but flowering and leaf colour were not affected. Salinity caused a decrease in stomatal conductance and evapotranspiration, which may prevent toxic levels being reached in the shoot. Net photosynthesis was reduced in plants subjected to salinity, although this response was evident much later than the decrease in stomatal conductance. Stem water potential was a good indicator of salt stress in C. citrinus. The relative salt tolerance of Callistemon was related to storage of higher levels of Na+ and Cl− in the roots compared with the leaves, especially in the case of Na+, which could have helped to maintain the quality of plants. The results show that saline water (around 4 dS·m−1) could be used for growing C. citrinus commercially. However, the cumulative effect of irrigating with saline water for 11 months was a decrease in photosynthesis and intrinsic water use efficiency, meaning that the interaction of the salinity level and the time of exposure to the salt stress should be considered important in this species. [ABSTRACT FROM AUTHOR]

We analyze the scaling propertiesof grafted polyrotaxanes and compare the resulting scaling laws withmolecular dynamics simulations. These molecules display a resemblanceto bottle brushes, but the mobility of the rotors yields a backbonetension that is uniform along its contour. Properties like brush extension,backbone tension, and rotor mobility as functions of rotor densityand degree of polymerization of grafted chains are well covered bya simple scaling model. The dynamics of rotor release after a breakupof the polyrotaxanea process recently observed in laboratoryexperimentsis studied in detail. It consists of three stages:a rapid backbone retraction, a driven rotor expulsion, and a diffusivetransport. The complexity of this process, which may be exploitedfor drug delivery systems, is asking for further in-depth simulationstudies. [ABSTRACT FROM AUTHOR]

Hydrothermal process has been employed to synthesize titanium oxide (TiO) bottle brush. The nanostructured bottle brushes with tetragonal nanorods of ~75 nm diameter have been synthesized by changing the nature of the precursors and hydrothermal processing parameters. The morphological features and structural properties of TiO films were investigated by field emission scanning electron microscopy, X-ray diffraction, high-resolution transmission electron spectroscopy, Fourier transform Raman spectroscopy, and X-ray photoelectron spectroscopy. The influence of such nanostructures on the performance of dye-sensitized solar cells (DSSCs) is investigated in detail. The interface and transient properties of these nanorods and bottle brush-based photoanodes in DSSCs were analyzed by electrochemical impedance spectroscopic measurements in order to understand the critical factors contributing to such high power conversion efficiency. Surface area of sample was recorded using Brunauer-Emmett-Teller measurements. It is found that bottle brush provides effective large surface area 89.34 m g which is much higher than TiO nanorods 63.7 m g. Such effective surface area can facilitate the effective light harvesting, and hence improves the dye adsorption and the photovoltaic performance of DSSCs, typically in short-circuit photocurrent and power conversion efficiency. A best power conversion efficiency of 6.63 % has been achieved. We believe that the present device performance would have wide interests in dye-sensitized solar cell research. [ABSTRACT FROM AUTHOR]

Two new natural-track pre-variety germplasms (selected class), Antelope Creek and Pleasant Valley bottlebrush squirreltail (Elymus elymoides (Raf.) Swezey "ssp. C" [Poaceae]), were released by the USDA Agricultural Research Service and the Utah Agricultural Experiment Station in 2009 and 2010, respectively. Antelope Creek Germplasm is recommended for use in the western Blue Mountains of Oregon and the eastern Cascade slopes and foothills of Oregon and northeastern California. Pleasant Valley Germplasm is recommended for use in the eastern Blue Mountains of Oregon, Washington, and Idaho. Both germ - plasms are members of the unofficially designated bottlebrush squirreltail "subspecies C," which possesses a distribution that is centered in central and eastern Oregon. [ABSTRACT FROM AUTHOR]

Methanol extracts of Callistemon viminalis (Sol. Ex Gaertner) G.Don Ex Loudon fruits, bark and leaves were tested for molluscicidal activity. Snails were collected and kept in dechlorinated water under standard condition. Ten adults Biomphalaria alexandrina, of the same size, were introduced in plastic acquaria for each experiment. The fruits, barks and leaves were extracted with methanol and the methanol extracts were kept for testing as molluscicides. Different extracts proved to have molluscicidal activity against the vector of schistosomiasis, B. alexandrina snails. LC50 values for C. viminalis fruits, bark and leaves were 6.2, 32 and 40 ppm respectively. The C. viminalis fruits extract showed the highest effect against the tested snails. Histopathological studies proved that the site of action of all tested extracts was localized in the digestive system and hermaphrodite gland. [ABSTRACT FROM AUTHOR]

A new, simple, precise, rapid, and selective high performance thin layer chromatographic (HPTLC) method has been developed and validated for the estimation of 1, 8-cineole in volatile oil of leaves of Callistemon citrinus obtained by hydro distillation. The method was validated as per ICH guidelines and can be utilized for routine analysis. The retention factor for 1, 8-cineole was found to be 0.52. The linearity was found to be in the range of 3 μg-12 μg. The recovery obtained for 1, 8-cineole was 98%, which is satisfactory. The result obtained in validation indicate the accuracy, reproducibility, and reliability of the developed HPTLC method for determination of 1, 8-cineole. [ABSTRACT FROM AUTHOR]

This study was carried out to evaluate toxicological and haematological effects of essential oils fromCallistemon viminalisandFerula gummosaagainstEphestia kuehniellalarvae through fumigant and topical exposure. The results indicated that fumigant LC10, LC30and LC50values were 8.42, 15.86 and 24.60 μl/l air forC. viminalisoil and 38.51, 57.75 and 76.44 μl/l air forF. gummosa, respectively. Also, topical LD values were measured to be 4.28, 9.64 and 16.91 μg insect −1forC. viminalisoil and 1.28, 3.39 and 6.65 μg insect−1forF. gummosaoil, respectively. Haematological observations showed that in comparison to fumigation, topical application of tested oils caused a drastic reduction in total hemocyte count of treated larvae in a dose-dependent manner at all time intervals. Also, it is shown that plasmatocytes and granulocytes were the most sensitive hemocytes ofE. kuehniellalarvae to the tested oils after topical application. So, it is concluded that topical application of essential oils ofC. viminalisandF. gummosaprovided effective control ofE. kuehniellacausing negative effects on its immune cells. [ABSTRACT FROM AUTHOR]

Holotypes do not exist for many names currently accepted in Calyptranthes (Myrtaceae – Myrciinae), either because the species was described with several syntypes or because the holotype is lost or destroyed. A thorough literature survey, extensive visits to international herbaria and analysis of online type collections has been undertaken. As a result, six lectotypifications and three neotypifications are made here. The type collection for Calyptranthes thomasiana is clarified. [ABSTRACT FROM AUTHOR]

Comparative investigation of hydro-distilled essential oils from leaves and flowers of Callistemon viridiflorous Sims (family Myrtaceae) grown in Egypt was carried out including their chemical composition and some of their bioactivities. The obtained oils revealed the presence of 19 and 22 identified constituents in the leaves and flowers, respectively. The oils were dominated by oxygenated compounds of 96.1 and 98.5% in leaves and flowers of C. viridiflorous respectively. Methyl eugenol was found to be the main component in leaves (89.1%) and flowers (95.1%). Hydrocarbon contents in both leaves and flowers were 3.9 and 1.5%, respectively. The unsaponifiable fraction of the fixed oil obtained by extracting the leaves of C. viridiflorous with petroleum ether was analyzed by GLC. The percentage of hydrocarbons and sterols were found to be 76.9 and 2.9%, respectively. Nonane (12.0%), octadecane (11.0%) and hexane (9.1%) were found as the major hydrocarbon constituents. Stigmasterol (1.3%), β-sitosterol (0.9%) and cholesterol (0.7%) were the major phytosterol constituents. Analysis of methylated fatty acid fraction of C. viridiflorous leaves extract by GLC revealed that the percentage of saturated fatty acids was higher than that of unsaturated fatty acids being 84.5 and 14.9%, respectively. Arachidic (42.4%) and palmitic (37.0%) acids were the major identified saturated fatty acid while oleic acid (5.5%) was the major identified unsaturated fatty acid. The oils of leaves and flowers of C. viridiflorus exhibited broad spectrum antimicrobial activity against both gram- positive and gram-negative bacteria as well as Candida albicans yeast. [ABSTRACT FROM AUTHOR]