Evaluation of the antioxidant properties of carexanes in AGS cells transfected with the Helicobacter pylori's protein HspB.

Naturally derived compounds represent a potential source of pharmacologically active drugs able to contrast different diseases, including gastric cancer, a multifactorial disease, in which the important role played by H. pylori infection has been demonstrated. Carexanes, stilbene derivatives, isolated from plants of the Carex distachya Desf., are unusual secondary metabolites with a tetracyclic skeleton arising from a cyclization of prenylstilbenoid precursors. In this study we firstly showed the ability of three purified carexanes CxB, CxG, and CxI to enhance the antioxidant response of AGS cells and to contrast the effect of the H. pylori's protein HspB. Among them CxI was the molecule that best modified the expression of genes involved in the antioxidant response. In particular, CxI was able to reduce Keap-1 gene expression and induce NQO1 gene expression, both at 4 and 24 h in AGS cells, as showed by real time PCR. Nrf2 induction was evident only at 24 h. Interestingly, the effect of CxI was stronger in HspB-transfected AGS cells, where Keap-1 gene expression was nearly abrogated. Finally, we demonstrated that CxI was able to reduce also COX-2 gene expression in HspB-transfected AGS cells, compared with untreated HspB-transfected cells, both at 4 and 24 h. This study first report that carexanes might represent candidate molecules able to contrast the deleterious effect of HspB protein but also to reduce the inflammatory process induced by H. pylori infection.

In vitro activity of alpha-viniferin isolated from the roots of Carex humilis against Mycobacterium tuberculosis.

This study explores the antitubercular activity of α-viniferin, a bioactive phytochemical compound obtained from Carex humilis. α-Viniferin was active against both drug-susceptible and -resistant strains of Mycobacterium tuberculosis at MIC50s of 4.6 µM in culture broth medium and MIC50s of 2.3-4.6 µM inside macrophages and pneumocytes. In combination with streptomycin and ethambutol, α-viniferin exhibited an additive effect and partial synergy, respectively, against M. tuberculosis H37Rv. α-Viniferin also did not show cytotoxicity in any of the cell lines tested up to a concentration of 147 µM, which gives this compound a selectivity index of >32. Moreover, α-viniferin was active against 3 Staphylococcus species, including methicillin-susceptible Staphylococcus aureus (MSSA), methicillin-resistant Staphylococcus aureus (MRSA), and methicillin-resistant Staphylococcus epidermidis (MRSE).

The effect of iron plaque on lead translocation in soil-Carex cinerascens kukenth. system.

A pot experiment was conducted to investigate the effect of iron plaque on Pb uptake by and translocation in Carex cinerascens Kukenth. grown under open-air conditions. Using Scanning Electron Microscopy and Energy Dispersive X-Ray Spectrometry, iron plaque was present as an amorphous coating on root surfaces with uneven distribution. The amount of iron plaque increased significantly with increasing Fe additions regardless of Pb additions. The presence of iron plaque on the root surface of Carex cinerascens Kukenth. increased the concentrations of Pb adsorbed by iron plaque. The Pb percentage in whole roots increased by 14.52% at 500 mg kg(-1) Fe treatment than at 0 mg kg(-1) Fe, and the distribution coefficient (DC) of Pb and translocation factor (TF) root increased with Fe additions, but translocation factor (TF) shoot decreased with Fe additions. The results suggested that iron plaque could promote the translocation of Pb from soil to roots to some extent, and it played a role to reduce heavy metals pollution of Poyang Lake wetland.

Comparison of three pretreatment methods for the analysis of distributions and hydrogen isotopic compositions of leaf wax n-fatty acids in natural samples.

RATIONALE: The hydrogen isotopic compositions (δ(2)H values) of leaf wax n-fatty acids (n-FAs) are widely used as powerful biomarkers in biogeochemical and paleoenvironmental studies. However, the use of a variety of pretreatment methods to isolate n-FAs from natural samples for the measurement of δ(2)H values potentially causes discrepancies in the measured δ(2)H values, thereby confounding their use as a biomarker. METHODS: We tested three typical pretreatment methods for the analysis of the distributions and δ(2)H values of n-FAs from terrestrial higher plants (Carex siderosticta Hance and Ilex chinensis Sim), surface soil, and lacustrine sediment. Method 1 employed an aminopropyl-bonded solid phase to selectively separate free n-FAs from extractable lipids, while Methods 2 and 3 involved alkali- and acid-catalysed chemical reactions in extractable lipids prior to isolation of the n-FAs. RESULTS: Methods 2 and 3 yielded higher amounts of C16-C24 n-FAs and of certain long-chain n-FAs than Method 1 due to the release of the corresponding ester-bound n-FAs by saponification and transesterification reactions, respectively. Although additional ester-bound n-FAs were recovered by Methods 2 and 3, there were no significant differences in the δ(2)H results for all homologous n-FAs from the two plants and for mid- and long-chain n-FAs from the soil and sediment among the three pretreatment methods. CONCLUSIONS: Our study indicates that the three different pretreatment methods might not seriously influence the interpretations of δ(2)H values of sedimentary long-chain n-FAs as a terrestrial paleohydrological proxy; however, the release of ester-bound n-FAs by alkali- and acid-catalysed chemical reactions means that users should be cautious when interpreting and comparing distribution data of n-FAs from natural samples with different pretreatment protocols.

Capillary interception of floating particles by surface-piercing vegetation.

Surface-piercing vegetation often captures particles that flow on the water surface, where surface tension forces contribute to capture. Yet the physics of capillary capture in flow has not been addressed. Here we model the capture of floating particles by surface-piercing collectors at moderately low Reynolds numbers (Re<10). We find a trade-off between the capillary force, which increases with the collector diameter, and the relative size of the meniscus, which decreases with the collector diameter, resulting in an optimal collector diameter of ~1-10 mm that corresponds to the regime in which many aquatic plant species operate. For this diameter range the angular distribution of capture events is nearly uniform and capture can be orders of magnitude more efficient than direct interception, showing that capillary forces can be major contributors to the capture of seeds and particulate matter by organisms.

Evaluating Escherichia coli removal performance in stormwater biofilters: a preliminary modelling approach.

Stormwater biofilters are not currently optimised for pathogen removal since the behaviour of these pollutants within the stormwater biofilters is poorly understood. Modelling is a common way of optimising these systems, which also provides a better understanding of the major processes that govern the pathogen removal. This paper provides an overview of a laboratory-scale study that investigated how different design and operational conditions impact pathogen removal in the stormwater biofilters. These data were then used to develop a modelling tool that can be used to optimise the design and operation of the stormwater biofilters. The model uses continuous simulations where adsorption and desorption were dominant during wet weather periods and first order die-off kinetics were significant in dry periods between the wet weather events. Relatively high Nash Sutcliffe Efficiencies (>0.5) indicate that the calibrated model is in good agreement with observed data and the optimised model parameters were comparable with values reported in the literature. The model's sensitivity is highest towards the adsorption process parameter followed by the die-off and desorption rate parameters, which implies that adsorption is the governing process of the model. Vegetation is found to have an impact on the wet weather processes since the adsorption and desorption parameters vary significantly with the different plant configurations. The model is yet to be tested against field data and needs to be improved to represent the effect of some other biofilter design configurations, such as the inclusion of the submerged zone.

Adsorption of chloramphenicol from water using Carex meyeriana Kunth-derived hierarchical porous carbon with open channel arrays.

A carbon material with both open macrochannel arrays and abundant micro/mesopores was prepared, characterized, and applied for removing chloramphenicol (CAP) from water. In the preparation process, Carex meyeriana Kunth (CM) with natural channel arrays was used as the precursor for producing the biochar, and NaOH was used for removing silicon and formatting micro- and mesopores of the porous carbon. The product (PCCM) exhibited the highest specific surface area (2700.24 m2 g-1) among the reported CM-derived porous carbons. The adsorption performances of PCCM were evaluated through batch adsorption experiments. The maximum adsorption capacity of PCCM toward CAP was 1659.43 mg g-1. The adsorption mechanism was investigated with the aid of theoretical calculations. Moreover, PCCM exhibited better performance than other porous carbon adsorbents in fixed-bed experiments, which may be due to its structural advantages.

Ultrastructural and biochemical alterations in rats exposed to crude extract of Carex baccans and Potentilla fulgens.

The use of plants as a source of medicine is an important component of the health care system in rural India. Carex baccans (Cyperaceae) and Potentilla fulgens (Rosaceae) have been known since ancient times in northeast India for their antitumor, antidiabetic, and antihelmintic properties. The present study was designed to determine the subacute toxicity profile of the root tuber extract of C. baccans and root-peel extract of P. fulgens in Wistar rats. The subacute oral toxicity was conducted using sublethal doses of 40, 50, 100, 150, 200, and 400 mgkg-1 body weights. Surface topographical and ultrastructural observations of liver and intestinal microvilli showed remarkable deformation and disruption, accompanied by quantitative changes in the liver enzymes, i.e., aspartate aminotransferase and alanine aminotransferase in comparison to those of the control group. Apoptotic cell death was observed in the liver cells of rats exposed to both of the plant extracts. A significant increase in splenic lymphocyte count was also observed in rats exposed to the highest concentration of both extracts. The results showed that consumption of the plant extracts at higher doses may cause toxicological effect if treatment continues for a long time.

RP-HPLC analysis of phenolic acids of selected Central European Carex L. (Cyperaceae) species and its implication for taxonomy.

Eighteen species belonging to the Carex genus were checked for the presence and the amount of eight phenolic acids (p-hydroxybenzoic, vanillic, caffeic, syringic, protocatechuic, p-coumaric, sinapic, and ferulic) by means of HPLC. Both the free and bonded phenolic acids were analyzed. The majority of the analyzed acids occurred in the studied species in relatively high amounts. The highest concentrations found were caffeic acid and p-coumaric acid, for which the detected levels were negatively correlated. A very interesting feature was the occurrence of sinapic acid, a compound very rarely detected in plant tissues. Its distribution across the analyzed set of species can be hypothetically connected with the humidity of plants' habitats. Several attempted tests of aggregative cluster analysis showed no similarity to the real taxonomical structure of the genus Carex. Thus, the phenolic acids' composition cannot be considered as the major taxonomical feature for the genus Carex.

A Clinical Trial to Evaluate the Efficacy of α-Viniferin in Staphylococcus aureus - Specific Decolonization without Depleting the Normal Microbiota of Nares.

Staphylococcus aureus is currently a significant multidrug-resistant bacterium, causing severe healthcare-associated and community-acquired infections worldwide. The current antibiotic regimen against this pathogen is becoming ineffective due to resistance, in addition, they disrupt the normal microbiota. It highlights the urgent need for a pathogen-specific drug with high antibacterial efficacy against S. aureus. α-Viniferin, a bioactive phytochemical compound, has been reported to have excellent anti-Staphylococcus efficacy as a topical agent. However, so far, there were no clinical trials that have been conducted to elucidate its efficacy. The present study aimed to investigate the antibacterial efficacy of α-viniferin against S. aureus in a ten-day clinical trial. Based on the results, α-viniferin showed 50% minimum inhibitory concentrations (MIC50 values) of 7.8 µg/ml in culture broth medium. α-Viniferin was administered in the nares three times a day for ten days using a sterile cotton swab stick. Nasal swab specimens were collected before (0 days) and after finishing the trial (10th day), and then analyzed. In the culture and RT-PCR-based analysis, S. ureus was reduced significantly: 0.01. In addition, 16S ribosomal RNA-based amplicon sequencing analysis showed that S. aureus reduced from 51.03% to 23.99% at the genus level. RNA-seq analysis was also done to gain insights into molecular mechanisms of α-viniferin against S. aureus, which revealed that some gene groups were reduced in 5-fold FC cutoff at two times MIC conditions. The study results demonstrate α-viniferin as a potential S. aureus-specific drug candidate.

Optimized purification process of polysaccharides from Carex meyeriana Kunth by macroporous resin, its characterization and immunomodulatory activity.

The analytical hierarchy process (AHP) combined with response surface methodology (RSM) was used to optimize the purification conditions of crude polysaccharides from Carex meyeriana Kunth (CMKP) by macroporous resin. The optimal purification conditions as follows: elution volume of 2.74 BV, flow rate of 1.88 BV/h, and sample concentration of 2.10 mg/mL. Under the optimal conditions, the purification comprehensive score was 63.59 ±â€¯1.56% (n = 3), which was agreed closely to the predicted value (64.02%). Two fractions of polysaccharides (CMKP-1 and CMKP-2) were obtained using a DEAE-52 column. Fourier Transform infrared (FTIR) spectroscopy spectra revealed the general characteristic absorption peaks of CMKP-1 and CMKP-2. Congo-red test indicated that CMKP-1 and CMKP-2 have triple helix conformation. CMKP-1 and CMKP-2 were both composed of Man, Rib, Rha, GluA, GalA, Glu, Gal, Xyl, Ara and Fuc in a molar ratio of 8.93:1:4.62:1.41:1.78:10.7:24.69:4.51:15.92:1.27 and 7.85:1:5.05:1.99:3.15:12.47:15.41:1.54:6.91:3.15, respectively. The major molecular weight of CMKP-1 and CMKP-2 was 22.30 kDa and 48.10 kDa, respectively. Moreover, CMKP-1 and CMKP-2 had immunostimulatory effects on RAW264.7 cells in a certain concentration range. It could be used as potential immunomodulatory agents in medicine or functional food fields.

Wetland soil and vegetation bismuth content following experimental deposition of bismuth pellets.

Bismuth pellets have been approved as a non-toxic alternative to lead pellets in Canada since 1997 but, to our knowledge, there is little literature for soil and vegetation bismuth content in areas of bismuth pellet deposition. The present study addresses this shortcoming by measuring wetland soil and vegetation bismuth content following experimental deposition of bismuth pellets under ambient and experimentally increased acidic deposition conditions. We manipulated 24 plots in a fully factorial design (bismuth shot x soil acidification) in a south-eastern Ontario freshwater wetland during 1999-2003. Soil pH (range 6.5-7.3) increased significantly (p = 0.001) during the experimental period but there were no significant differences amongst treatments (p = 0.79). Significantly (p < 0.05) greater bismuth concentrations were measured in soil receiving bismuth pellets (mean +/- SE, n = 6; with acidification = 2.55 +/- 1.02 microg Bi g(-1) dry mass [DM]; without acidification = 6.40 +/- 2.23 microg Bi g(-1) DM) compared to plots that were not seeded with bismuth pellets (without acidification = 0.42 +/- 0.09 microg Bi g(-1) DM; with acidification = 0.39 +/- 0.10 microg Bi g(-1) DM). Nevertheless, bismuth levels in 20 of 24 aboveground tissue samples from the Carex lacustris-Agrostis scabra community were below detection levels (0.057 microg Bi g(-1) DM); the other samples ranged from 0.065 to 0.095 microg Bi g(-1) DM, similar to global background levels. Primary productivity in plots receiving bismuth pellets and soil acidification was not significantly (p = 0.15) different to vegetation in plots that were not manipulated. The results suggest bismuth mobilization from bismuth pellets into soil but not to aboveground vegetation.

Traffic-emitted metal status and uptake by Carex meyeriana Kunth and Thelypteris palustris var. pubescens Fernald growing in roadside turfy swamp in the Changbai Mountain area, China.

Six traffic-emitted metals (Cr, Zn, Cu, Cd, Pb, and Ni) were determined in soil and plants for below- and aboveground parts along different distances from highway to evaluate their behavior and uptake by Carex meyeriana Kunth and Thelypteris palustris var. pubescens Fernald growing in turfy swamps. The results indicated that the different plant tissues showed significantly different levels of metal content. Nonlinear regression analysis indicated that metal contents leveled off at constant values before they decreased as the distance from the roadside increased. The high R2 values of the regression model indicated good fit of the exponential function applied to depict the distribution pattern of the metal elements. It was deduced that Cr, Cu, and Cd in Thelypteris palustris var. pubescens Fernald were mainly derived from the soil; Carex meyeriana Kunth and Thelypteris palustris var. pubescens Fernald absorbed Pb mainly through the stomata from atmospheric depositions; Cr, Cu, and Cd in Carex meyeriana Kunth and Zn in Thelypteris palustris var. pubescens Fernald were mainly affected by soil and atmospheric depositions. After excluding the effects of traffic, only the bioaccumulation factor of Cd (1.34) in Carex meyeriana Kunth and the translocation factor of Zn (1.13) in Thelypteris palustris var. pubescens Fernald were greater than 1, suggesting that Carex meyeriana Kunth could be a good candidate for assimilating Cd from soils and Thelypteris palustris var. pubescens Fernald could be suitable for the phytoextraction of Zn.

Fabrication of cellulose nanocrystal from Carex meyeriana Kunth and its application in the adsorption of methylene blue.

Cellulose nanocrystal (CNC) was extracted from Carex meyeriana Kunth (CMK) by a combination of TEMPO oxidation and mechanical homogenization method, and used to remove methylene blue (MB) from aqueous solution. After alkali-oxygen treatment, the aqueous biphasic system (polyethylene glycol/inorganic salt) was applied to further remove lignin from CMK. The characteriazation of CNC, and the effects of H2O2 dosage, CNC dosage, adsorption time, and initial MB concentration on the MB removal capacity of CNC were investigated. The results showed that the removal percentage of MB by CNC was raised with the increase of H2O2 and CNC dosage. The adsorption kinetics of prepared CNC followed the pseudo-second-order model, and the adsorption isotherms fitted well to the Langmuir model with a calculated maximum adsoption capacity of 217.4mg/g, which was higher than those of CNC extracted by acid hydrolysis method, indicating CNC extracted from CMK had promising potentials in the field of MB adsorption.

Six-step synthesis of (S)-brevicolline from (S)-nicotine.

[reaction: see text] A six-step synthesis of (S)-brevicolline from (S)-nicotine is reported. Regioselective trisubstitution of the pyridine ring of nicotine, followed by successive Suzuki cross-coupling and Buchwald amination reactions, afforded the enantiopure beta-carboline alkaloid, brevicolline.

Structures of bioactive carexanes from the roots of Carex distachya Desf.

Four metabolites, named carexanes I-L, have been isolated from the roots of Carex distachya Desf, an herbaceous plant living in the Mediterranean maquis, together with three known compounds, already isolated from the aerial part of the plant. All the compounds have been characterized on the basis of their spectroscopic properties. Carexane I derived from the lose of a proton from the C-18 carbon of an intermediate isopropyl cation. Its stereostructure has been elucidated by Mosher's method, NOESY/ROESY experiments and computational calculations. The bioactivity on seed germination and root/shoot growth of Lactuca sativa L. of all the isolated compounds is also reported.

Screening the wetland plant species Alisma plantago-aquatica, Carex rostrata and Phalaris arundinacea for innate tolerance to zinc and comparison with Eriophorum angustifolium and Festuca rubra Merlin.

Several wetland plant species appear to have constitutive metal tolerance. In previous studies, populations from contaminated and non-contaminated sites of the wetland plants Typha latifolia, Phragmites australis, Glyceria fluitans and Eriophorum angustifolium were found to be tolerant to high concentrations of metals. This study screened three other species of wetland plants: Alisma plantago-aquatica, Carex rostrata and Phalaris arundinacea for innate tolerance to zinc. The degree of tolerance was compared to known zinc-tolerant E. angustifolium and Festuca rubra Merlin. It was found that A. plantago-aquatica and P. arundinacea did not posses innate tolerance to zinc, but that C. rostrata was able to tolerate elevated levels of zinc, at levels comparable to those tolerated by E. angustifolium and F. rubra Merlin. The findings support the theory that some wetland angiosperm species tend to be tolerant to exposure to high levels of metals, regardless of their origin.

Phenolic constituents of Carex vulpinoidea seeds and their tyrosinase inhibitory activities.

Two new phenolics, a stilbenoid, vulpinoideol A (1), and a chalcone, vulpinoideol B (2), along with ten known compounds (3-12) were isolated from Carex vulpinoidea Michx. seeds. The structures of compounds 1-12 were elucidated based on spectrometric and spectroscopic analyses including HRESIMS, 1D and 2D NMR data. All compounds were evaluated for their tyrosinase enzyme inhibitory activities.

Silicified structures affect leaf optical properties in grasses and sedge.

Silicon (Si) is an important structural element that can accumulate at high concentrations in grasses and sedges, and therefore Si structures might affect the optical properties of the leaves. To better understand the role of Si in light/leaf interactions in species rich in Si, we examined the total Si and silica phytoliths, the biochemical and morphological leaf properties, and the reflectance and transmittance spectra in grasses (Phragmites australis, Phalaris arundinacea, Molinia caerulea, Deschampsia cespitosa) and sedge (Carex elata). We show that these grasses contain >1% phytoliths per dry mass, while the sedge contains only 0.4%. The data reveal the variable leaf structures of these species and significant differences in the amount of Si and phytoliths between developing and mature leaves within each species and between grasses and sedge, with little difference seen among the grass species. Redundancy analysis shows the significant roles of the different near-surface silicified leaf structures (e.g., prickle hairs, cuticle, epidermis), phytoliths and Si contents, which explain the majority of the reflectance and transmittance spectra variability. The amount of explained variance differs between mature and developing leaves. The transmittance spectra are also significantly affected by chlorophyll a content and calcium levels in the leaf tissue.

Inhibition of Pseudomonas aeruginosa and Escherichia coli O157:H7 biofilm formation by plant metabolite ε-viniferin.

Pathogenic biofilms are associated with persistent infection due to their high resistances to diverse antibiotics. Pseudomonas aeruginosa infects plants, animals, and humans and is a major cause of nosocomial diseases in patients with cystic fibrosis. In the present study, the antibiofilm abilities of 522 plant extracts against P. aeruginosa PA14 were examined. Three Carex plant extracts at a concentration of 200 µg/mL inhibited P. aeruginosa biofilm formation by >80% without affecting planktonic cell growth. In the most active extract of Carex pumila , resveratrol dimer ε-viniferin was one of the main antibiofilm compounds against P. aeruginosa. Interestingly, ε-viniferin at 10 µg/mL inhibited biofilm formation of enterohemorrhagic Escherichia coli O157:H7 by 98%. Although Carex extracts and trans-resveratrol are known to possess antimicrobial activity, this study is the first to report that C. pumila extract and ε-viniferin have antibiofilm activity against P. aeruginosa and E. coli O157:H7.