The molecular regulatory mechanism of reed canary grass under salt, waterlogging, and combined stress was analyzed by transcriptomic analysis.

BACKGROUND: Reed canary grass has been identified as a suitable species for restoring plateau wetlands and understanding plant adaptation mechanisms in wetland environments. In this study, we subjected a reed canary grass cultivar 'Chuanxi' to waterlogging, salt, and combined stresses to investigate its phenotypic characteristics, physiological indices, and transcriptome changes under these conditions. RESULTS: The results revealed that the growth rate was slower under salt stress than under waterlogging stress. The chlorophyll content and energy capture efficiency of the PS II reaction center decreased with prolonged exposure to each stress. Conversely, while the activities of enzymes associated with respiratory metabolism, as well as MDA, PRO, Na+, and K+-ATPase, increased. The formation of distinct aerenchyma was observed under waterlogging stress and combined stress. Transcriptome sequencing analysis identified 5,379, 4,169, and 14,993 DEGs under CK vs. W, CK vs. S, and CK vs. SW conditions, respectively. The WRKY was found to be the most abundant under waterlogging stress, whereas the MYB predominated under salt stress and combined stress. Glutathione metabolic pathways and Plant hormone signal transduction have also been found to play important roles in stress. CONCLUSION: By integrating phenotypic, physiological, anatomical, and transcriptomic, this research provides valuable insights into how reed canary grass responds to salt, waterlogging, and combined stresses. These findings may inform the ecological application of reed canary grass in high-altitude wetlands and for breeding purposes.

Development of Low Glycemic Index Pancakes Formulated with Canary Seed (Phalaris Canariensis) Flour.

Consumers prefer food products that, in addition to nutritional properties, also have effects beneficial to health. Non-conventional food plants such as canary seed (Phalaris canariensis) constitute an alternative in the food industry due to nutritional properties, chemical, and bioactive potential. The aim of this research was to develop pancake formulations with the inclusion of canary seed flour to evaluate their proximate composition, overall score, taste and texture sensory acceptability, and glycemic index. Pancakes based on whole-wheat flour mixed with canary seed flour were developed at four substitution levels (control 0, 10, 30, and 50%). The formulations exhibited attractive nutritional properties, mainly due to the levels of protein (~ 8.7%), minerals (~ 5.1%), and total dietary fiber (4.7-5.9%). The overall score and taste showed a statistical difference (p < 0.05) between the formulations. The flours with 10 and 30% showed high sensory acceptability with scores of 6.22 and 6.67 respect to 7-point hedonic scale, between the categories "I like it" and "I like it a lot". All formulations presented a low glycemic index (34-39%) that was significantly influenced (p < 0.05) as the level of substitution increased. The findings represent a new approach to the use of canary seed in the development of healthy food products.

Recovery of microelements from municipal sewage sludge by reed canary grass and giant miscanthus.

The aim of the study was to evaluate the content, uptake, and utilization of Al, Mn, Fe, Co, and Mo from municipal sewage sludge by the reed canary grass (RCG) and the giant miscanthus (MG). The impact of sewage sludge on the mass ratios between microelements contained in the plant biomass was analyzed as well. The long-term field experiment consisted in application of four levels of fertilization with sewage sludge: 10, 20, 40, and 60 Mg DM·ha-1. A non-fertilized control object (0 Mg DM·ha-1) was used as well. The miscanthus biomass was characterized by higher content of Al and Mn, whereas higher levels of Fe, Co, and Mo were determined in the reed canary grass biomass. As in the case of the element content, the giant miscanthus was characterized by highest level of Al and Mn uptake, while the highest uptake of Fe, Co, and Mo was exhibited by the reed canary grass. In the group of the analyzed microelements, the giant miscanthus showed the highest the recovery of Mo (47%) followed by Mn (39%), Fe (35%), and Co (15%), and the lowest uptake was determined in the case of Al (5%).

In addition to the use of their biomass for the production of renewable energy, energy crops (reed canary grass, giant miscanthus) can be used to recover microelements from municipal sewage sludge. Energy crop biomass can therefore be a potential source of microelements in animal feed. Attention was paid to the mass ratios of Fe:Mn, Fe:Al, Fe:Co, Fe:Mo, Mn:Al, Mn:Co, Mn:Mo, and Co:Mo in the biomass yield of the species used.

Application of Molecular Dynamics Simulations to Determine Interactions between Canary Seed (Phalaris canariensis L.) Bioactive Peptides and Skin-Aging Enzymes.

Food bioactive peptides are well recognized for their health benefits such as antimicrobial, antioxidant, and antihypertensive benefits, among others. Their drug-like behavior has led to their potential use in targeting skin-related aging factors like the inhibition of enzymes related with the skin-aging process. In this study, canary seed peptides (CSP) after simulated gastrointestinal digestion (<3 kDa) were fractioned by RP-HPLC and their enzyme-inhibition activity towards elastase and tyrosinase was evaluated in vitro. CSP inhibited elastase (IC50 = 6.2 mg/mL) and tyrosinase (IC50 = 6.1 mg/mL), while the hydrophobic fraction-VI (0.2 mg/mL) showed the highest inhibition towards elastase (93%) and tyrosinase (67%). The peptide fraction with the highest inhibition was further characterized by a multilevel in silico workflow, including physicochemical descriptor calculations, antioxidant activity predictions, and molecular dynamics-ensemble docking towards elastase and tyrosinase. To gain insights into the skin permeation process during molecular dynamics simulations, based on their docking scores, five peptides (GGWH, VPPH, EGLEPNHRVE, FLPH, and RPVNKYTPPQ) were identified to have favorable intermolecular interactions, such as hydrogen bonding of polar residues (W, H, and K) to lipid polar groups and 2-3 Å van der Waals close contact of hydrophobic aliphatic residues (P, V, and L). These interactions can play a critical role for the passive insertion of peptides into stratum corneum model skin-membranes, suggesting a promising application of CSP for skin-aging treatments.

Effect of phenyllactic acid on silage fermentation and bacterial community of reed canary grass on the Qinghai Tibetan Plateau.

BACKGROUND: This study aimed to investigate the effect of phenyllactic acid as an additive on silage fermentation and bacterial community of reed canary grass (RCG, Phalaris arundinacea L.) on the Qinghai Tibetan Plateau. At the heading stage, RCG was harvested, chopped and ensiled in small bag silos. The silage was treated without (control, 1.0 g/mL sterile water, on a fresh matter basis (FM)) or with phenyllactic acid (PLA, 3 mg/mL, FM), antimicrobial additive (PSB, a mixture of potassium sorbate and sodium benzoate, 2%, FM), lactic acid bacteria inoculant (LABi, L. plantarum + L. curvatus, 1 × 106 cfu/g, FM) and PLA + LABi, and then stored in a dark room at the ambient temperature (5 ~ 15 °C) for 60 days. RESULTS: Compared with control, PLA decreased lactic acid, acetic acid and ammonia-N contents, and subsequently increased CP content of RCG silage. PLA enhanced the growth of lactic acid bacteria and reduced the count of yeasts (P < 0.05) in RCG silage, with reduced bacterial richness index (Chao1), observed operational taxonomic units and diversity index (Simpson). In relative to control, moreover, PLA and PLA + LABi increased the relative abundance of Lactococcus in RCG silage by 27.73 and 16.93%, respectively. CONCLUSIONS: Therefore, phenyllactic acid at ensiling improved nutritional quality of RCG silage by advancing the disappearance of yeasts and the dominance of Lactococcus.

Canary Seed (Phalaris canariensis L.) Peptides Prevent Obesity and Glucose Intolerance in Mice Fed a Western Diet.

Previous research showed that canary seed (Phalaris canariensis L.) peptides (CSP) possess robust in vitro antiobesity properties via inhibition of pancreatic lipase (PL). Nevertheless, no studies have yet explored their antiobesity properties in vivo. Consequently, we investigated the effects of CSP in C57BL/6J mice under a Western diet (WD). Mice were assigned into groups and fed a normal diet (ND) or a WD accompanied by an oral dose of CSP (250 or 500 mg/kg/day), orlistat (40 mg/kg/day), or distilled water. The results showed that consuming CSP can provide metabolic benefits, including preventing weight gain by up to 20%, increasing glucose tolerance, and reducing insulin, leptin, and LDL/VLDL levels in plasma. Conversely, total ghrelin was unaffected by CSP-500, but decreased by CSP-250, and amplified by orlistat. Surprisingly, CSP-250 was more effective in preventing weight gain and promoting satiety than CSP-500. Parallel to this, protein absorption in CSP-500 was decreased, supported by a rise in fecal crude protein (+3.5%). Similarly, fecal fat was increased by orlistat (38%) and was unaffected by CSP-250 (3.0%) and CSP (3.0%), comparatively to WD (2.5%). Despite this, both CSP treatments were equally effective in decreasing hepatic steatosis and avoiding hyperlipidemia. Furthermore, the enzymatic analysis showed that CSP-PL complexes dissociated faster (15 min) than orlistat-PL complexes (41 min). Lastly, CSP did not affect expression of hepatic lipid oxidation genes ACO and PPAR-α, but reduced the expression of the hydrolase gene LPL, and lipogenesis related genes FAS and ACC. Taken together, these results suggest that CSP antiobesity mechanism relies on lipid metabolism retardation to increase fat transit time and subsequently suppress hunger.

Variability in ITS1 and ITS2 sequences of historic herbaria and extant (fresh) Phalaris species (Poaceae).

BACKGROUND: Phalaris species (Poaceae) occupy diverse environments throughout all continents except Antarctica. Phalaris arundinacea is an important forage, ornamental, wetland restoration and biofuel crop grown globally as well as being a wetland invasive. The nuclear ribosomal internal transcribed spacer (ITS) region has been used for Phalaris barcoding as a DNA region with high nucleotide diversity for Phalaris species identification. Recent findings that P. arundinacea populations in Minnesota USA are most likely native and not European prompted this analysis to determine whether Eurasian vs. native North American P. arundinacea differed in ITS regions. Our objectives were to amplify and compare ITS regions (ITS1 and ITS2) of historic herbaria (1882-2001) and extant (fresh) Phalaris specimens; analyze ITS regions for species-specific polymorphisms (diagnostic SNPs) and compare ITS regions of historic Phalaris specimens with known, extant Phalaris species. RESULTS: We obtained complete ITS1 and ITS2 sequences from 31 Phalaris historic (herbaria samples, 1908 to 2001) and five extant (fresh) specimens. Herbaria Phalaris specimens did not produce new SNPs (single nucleotide polymorphisms) not present in extant specimens. Diagnostic SNPs were identified in 8/12 (66.6%) Phalaris species. This study demonstrates the use of herbaria tissue for barcoding as a means for improved species identification of Phalaris herbaria specimens. No significant correlation between specimen age and genomic DNA concentration was found. Phalaris arundinacea showed high SNP variation within its clade, with the North American being distinctly different than other USA and most Eurasian types, potentially allowing for future identification of specific SNPs to geographic origin. CONCLUSIONS: While not as efficient as extant specimens to obtain DNA, Phalaris herbaria specimens can produce high quality ITS sequences to evaluate historic genetic resources and facilitate identification of new species-specific barcodes. No correlation between DNA concentration and age of historic samples (119 year range) occurred. Considerable polymorphism was exhibited in the P. arundinacea clade with several N. American accessions being distinct from Eurasian types. Further development of within species- and genus-specific barcodes could contribute to designing PCR primers for efficient and accurate identification of N. American P. arundinacea. Our finding of misidentified Phalaris species indicates the need to exercise stringent quality control measures on newly generated sequence data and to approach public sequence databases in a critical way.

Contrasting Water Quality Treatments Result in Structural and Functional Changes to Wetland Plant-Associated Microbial Communities in Lab-Scale Mesocosms.

The impact of contrasting water quality treatments on wetland plant-associated microbial communities was investigated in this study using 12 lab-scale wetland mesocosms (subsurface flow design) planted with reed canary grass (Phalaris arundinacea) or water speedwell (Veronica anagallis-aquatica) over a 13-week period. Mesocosms received water collected from two sites along the Grand River (Ontario, Canada) designated as having either high or poor water quality according to Grand River Conservation Authority classifications. All mesocosms were established using sediment collected from the high water quality site and received water from this source pre-treatment. Resulting changes to microbial community structure were assessed using PCR-denaturing gel gradient electrophoresis (DGGE) on microbial 16S rDNA sequences extracted from rhizoplane, rhizosphere, and water samples before and after exposure to water quality treatments. Functional community changes were determined using Biolog™ EcoPlates which assess community-level carbon source utilization profiles. Wetland mesocosm removal of inorganic nutrients (N, P) and fecal coliforms was also determined, and compared among treatments. Treatment-specific effects were assessed using a repeated measures restricted maximum likelihood (REML) analysis. Structural and functional characteristics of rhizoplane microbial communities were significantly influenced by the interaction between plant species and water treatment (P = 0.04, P = 0.01). Plant species-specific effects were observed for rhizosphere structural diversity (P = 0.01) and wetland water community metabolic diversity (P = 0.03). The effect of water treatment alone was significant for structural diversity measurements in wetland water communities (P = 0.03). The effect of plant species, water quality treatment, and the interaction between the two is dependent on the microhabitat type (rhizoplane, rhizosphere, or water). Rhizoplane communities appear to be more sensitive to water quality-specific environmental changes and may be a good candidate for microbial community-based monitoring of wetland ecosystems.

Inoculation of exogenous lactic acid bacteria exerted a limited influence on the silage fermentation and bacterial community compositions of reed canary grass straw on the Qinghai-Tibetan Plateau.

AIMS: This study evaluated the effects of exogenous lactic acid bacteria (LAB) on silage fermentation and bacterial community of reed canary grass (RCG) straw. METHODS AND RESULTS: The leaf, stem and whole crop of RCG straw were separately ensiled in small bag silos, without (control) or with inoculation of two exogenous LAB (LP, Lactobacillus plantarum; LB, Lactobacillus buchneri), and stored at ambient temperature of <20°C. Inoculation of exogenous LAB decreased (P < 0·05) bacterial alpha diversity and shifted (P < 0·05) bacterial community compositions, but did not change (P> 0·05) the relative abundance of Lactobacillus. Particularly, inoculation of LB increased (P < 0·05) acetic acid and propionic acid contents, decreased (P < 0·05) butyric acid (BA) and ammonia-N contents, separated (P < 0·05) the bacterial community in silage. However, the exogenous LAB inoculated silages were characterized by main distribution of yeasts, presence of undesirable bacterial genera such as Clostridium and high levels of BA and ammonia-N. CONCLUSION: Inoculation of exogenous LAB exerted a limited influence on the silage fermentation and bacterial community compositions of RCG straw on the Qinghai-Tibetan Plateau. SIGNIFICANCE AND IMPACT OF THE STUDY: Commercial LAB inoculants are not always efficient on enhancing silage quality and stability. Thus, an alternative additive for inhibiting undesirable microbes during storage is important to improve RCG silage quality on the Qinghai-Tibetan Plateau.

Preliminary screening of rhizobacteria for biocontrol of little seed canary grass (Phalaris minor Retz.) and wild oat (Avena fatua L.) in wheat.

Conventional weed control methods often have environmental impact. The present study was conducted to screen selected accessions of Pseudomonas for both potential biocontrol of Phalaris minor and Avena fatua and potential concurrent growth promotion of wheat. The four Pseudomonas strains (B11, T19, T24, and T75) were found positive for cyanide production, siderophore production, phosphorus solubilization, oxidase activity, catalase activity, and ACC deaminase activity in vitro. These strains were phytotoxic, causing up to 73.3% mortality in the lettuce seedling bioassay. Consortia of compatible Pseudomonas strains increased A. fatua and P. minor seedling mortality up to 50.0% and 56.7%, respectively, and reduced root length up to 73.8% and 53.9%, respectively, as compared with the uninoculated control. Consortia of compatible Pseudomonas strains increased wheat shoot length, root length, fresh biomass, dry biomass, and leaf greenness up to 41.6%, 100%, 79.9%, 81.5%, and 21.1%, respectively, over the uninoculated control. Four of the 11 Pseudomonas consortia tested expressed good weed suppression and wheat growth promotion capacity and deserve further experimentation. The findings from this study may lead to the formulation of bioherbicides that will improve human and environmental health.

Diterpenes from seeds of Phalaris canariensis and their PTP1B inhibitory activity and hypoglycemic effects in streptozotocin-induced diabetic mice.

This present study was to evaluate the protein tyrosine phosphatase 1B (PTP1B) inhibitory activity of nine diterpenes isolated from seeds of Phalaris canariensis, as well as their effect on streptozotocin-nicotinamide-induced type 2 diabetic mice. Their structures were established by spectroscopic analyses. Diterpenes, 1, 4, and 2 exhibited the strongest inhibitory activity on PTP1B with IC50 values of 6.9, 7.3, and 6.5 µM, respectively, The administration of 1-9 showed significant effect on hyperglycemia, among them 1, 4, and 2 reduced fasting glucose levels (55.65%, 54.27%, and 51.22%, respectively). Results revealed that diterpenes performed potential antidiabetic activity via inhibition of PTP1B.[Formula: see text].

Transcriptome characterization and differentially expressed genes under flooding and drought stress in the biomass grasses Phalaris arundinacea and Dactylis glomerata.

BACKGROUND AND AIMS: Perennial grasses are a global resource as forage, and for alternative uses in bioenergy and as raw materials for the processing industry. Marginal lands can be valuable for perennial biomass grass production, if perennial biomass grasses can cope with adverse abiotic environmental stresses such as drought and waterlogging. METHODS: In this study, two perennial grass species, reed canary grass (Phalaris arundinacea) and cocksfoot (Dactylis glomerata) were subjected to drought and waterlogging stress to study their responses for insights to improving environmental stress tolerance. Physiological responses were recorded, reference transcriptomes established and differential gene expression investigated between control and stress conditions. We applied a robust non-parametric method, RoDEO, based on rank ordering of transcripts to investigate differential gene expression. Furthermore, we extended and validated vRoDEO for comparing samples with varying sequencing depths. KEY RESULTS: This allowed us to identify expressed genes under drought and waterlogging whilst using only a limited number of RNA sequencing experiments. Validating the methodology, several differentially expressed candidate genes involved in the stage 3 step-wise scheme in detoxification and degradation of xenobiotics were recovered, while several novel stress-related genes classified as of unknown function were discovered. CONCLUSIONS: Reed canary grass is a species coping particularly well with flooding conditions, but this study adds novel information on how its transcriptome reacts under drought stress. We built extensive transcriptomes for the two investigated C3 species cocksfoot and reed canary grass under both extremes of water stress to provide a clear comparison amongst the two species to broaden our horizon for comparative studies, but further confirmation of the data would be ideal to obtain a more detailed picture.

The efficiency and economic aspects of phytoremediation technology using Phalaris arundinacea L. and Brassica napus L. combined with compost and nano SiO2 fertilization for the removal of PAH's from soil.

The paper presents an evaluation of efficiency and economic potential of the phytoremediation technology, based on the use of energy crops (P. arundinacea L. and B. Napus L.), combined with the fertilization with compost, supported by the addition of nano SiO2. The experiment was conducted in in-situ conditions, using two experimental blocks, divided according to used plant species. Each block included four types of plots with different fertilization treatments (control plots; treatment with nano SiO2; treatment with compost; treatment with mixture of compost and nano SiO2). During the studied period (three vegetation seasons), a cyclic analysis of 16 PAH's content were conducted. Furthermore, a quantitative determination of biomass production was performed as well as assessment of economic potential of different strategies. Data collected during research, shows that method based on energy crops use, due to the join effect of the dangerous pollutants removal and the production of removable energy resource, can be considered as sustainable and should be recommended for use during heavy polluted soil remediation. Moreover, it should be also noted, that the best results for both PAH's removal efficiency and biomass production, were acquired on plots with P. arundinacea L. cultivation, fertilized with mix of compost and nano SiO2.

Genotyping-by-sequencing through transcriptomics: implementation in a range of crop species with varying reproductive habits and ploidy levels.

The application of genomics in crops has the ability to significantly improve genetic gain for agriculture. Many marker-dense tools have been developed, but few have seen broad adoption in plant genomics due to issues of significant variations of genome size, levels of ploidy, single nucleotide polymorphism (SNP) frequency and reproductive habit. When combined with limited breeding activities, small research communities and scant sequence resources, the suitability of popular systems is often suboptimal and routinely fails to effectively balance cost-effectiveness and sample throughput. Genotyping-by-sequencing (GBS) encompasses a range of protocols including resequencing of the transcriptome. This study describes a skim GBS-transcriptomics (GBS-t) approach developed to be broadly applicable, cost-effective and high-throughput while still assaying a significant number of SNP loci. A range of crop species with differing levels of ploidy and degree of inbreeding/outbreeding were chosen, including perennial ryegrass, a diploid outbreeding forage grass; phalaris, a putative segmental allotetraploid outbreeding forage grass; lentil, a diploid inbreeding grain legume; and canola, an allotetraploid partially outbreeding oilseed. GBS-t was validated as a simple and largely automated, cost-effective method which generates sufficient SNPs (from 89 738 to 231 977) with acceptable levels of missing data and even genome coverage from c. 3 million sequence reads per sample. GBS-t is therefore a broadly applicable system suitable for many crops, offering advantages over other systems. The correct choice of subsequent sequence analysis software is important, and the bioinformatics process should be iterative and tailored to the specific challenges posed by ploidy variation and extent of heterozygosity.

A reassessment of the genome size-invasiveness relationship in reed canarygrass (Phalaris arundinacea).

Background and Aims: Genome size is hypothesized to affect invasiveness in plants. Key evidence comes from a previous study of invasive eastern North American populations of the grass Phalaris arundinacea: invasive genotypes with smaller genomes had higher growth rates, and genome sizes were smaller in the invasive vs. native range. This study aimed to re-investigate those patterns by examining a broader range of North American populations and by employing the modern best-practice protocol for plant genome size estimation in addition to the previously used protocol. Methods: Genome sizes were measured using both internal and pseudo-internal standardization protocols for 20 invasive and nine native range accessions of P. arundinacea. After a round of vegetative propagation to reduce maternal environmental effects, growth (stem elongation) rates of these accessions were measured in the greenhouse. Key Results: Using the best-practice protocol, there was no evidence of a correlation between genome size and growth rates (P = 0.704), and no evidence for differences in genome sizes of invasive and native range accessions (P > 0.353). However, using the older genome size estimation protocol, both relationships were significant (reproducing the results of the previous study). Conclusions: Genome size reduction has not driven increased invasiveness in a broad sample of North American P. arundinacea. Further, inappropriate genome size estimation techniques can create spurious correlations between genome size and plant traits such as growth rate. Valid estimation is vital to progress in understanding the potentially widespread effects of genome size on biological processes and patterns.

Isolation of Bacterial Endophytes from Phalaris arundinacea and their Potential in Diclofenac and Sulfamethoxazole Degradation.

Diclofenac (DCF), a non-steroidal anti-inflammatory drug (NSAID) and sulfamethoxazole (SMX), an antimicrobial agent, are in common use and can be often detected in the environment. The constructed wetland systems (CWs) are one of the technologies to remove them from the aquatic environment. The final effect of the treatment processes depends on many factors, including the interaction between plants and the plant-associated microorganisms present in the system. Bacteria living inside the plant as endophytes are exposed to secondary metabolites in the tissues. Therefore, they can possess the potential to degrade aromatic structures, including residues of pharmaceuticals. The endophytic strain MG7 identified as Microbacterium sp., obtained from root tissues of Phalaris arundinacea exposed to DCF and SMX was tested for the ability to remove 2 mg/l of SMX and DCF in monosubstrate cultures and in the presence of phenol as an additional carbon source. The MG7 strain was able to remove approximately 15% of DCF and 9% of SMX after 20 days of monosubstrate culture. However, a decrease in the optical density of the MG7 strain cultures was observed, caused by an insufficient carbon source for bacterial growth and proliferation. The adsorption of pharmaceuticals onto autoclaved cells was negligible, which confirmed that the tested strain was directly involved in the removal of DCF and SMX. In the presence of phenol as the additional carbon source, the MG7 strain was able to remove approximately 35% of DCF and 61% of SMX, while an increase in the optical density of the cultures was noted. The higher removal efficiency can be explained by adaptive mechanisms in microorganisms exposed to phenol (i.e. changes in the composition of membrane lipids) and by a co-metabolic mechanism, where non-growth substrates can be transformed by non-specific enzymes. The presence of both DCF and SMX and the influence of the supply frequency of CWs with the contaminated wastewater on the diversity of whole endophytic bacterial communities were demonstrated. The results of this study suggest the capability of the MG7 strain to degrade DCF and SMX. This finding deserves further investigations to improve wastewater treatment in CWs with the possible use of pharmaceuticals-degrading endophytes.

Impacts of silicon-based grass defences across trophic levels under both current and future atmospheric CO2 scenarios.

Silicon (Si) has important functional roles in plants, including resistance against herbivores. Environmental change, such as increasing atmospheric concentrations of CO2, may alter allocation to Si defences in grasses, potentially changing the feeding behaviour and performance of herbivores, which may in turn impact on higher trophic groups. Using Si-treated and untreated grasses (Phalaris aquatica) maintained under ambient (400 ppm) and elevated (640 and 800 ppm) CO2 concentrations, we show that Si reduced feeding by crickets (Acheta domesticus), resulting in smaller body mass. This, in turn, reduced predatory behaviour by praying mantids (Tenodera sinensis), which consequently performed worse. Despite elevated CO2 decreasing Si concentrations in P. aquatica, this reduction was not large enough to affect the feeding behaviour of crickets or their predator. Our results suggest that Si-based defences in plants have adverse impacts on both primary and secondary trophic taxa, and these are not likely to decline under future climate change scenarios.

Effects of citric acid and the siderophore desferrioxamine B (DFO-B) on the mobility of germanium and rare earth elements in soil and uptake in Phalaris arundinacea.

Effects of citric acid and desferrioxamine B (DFO-B) on the availability of Ge and selected rare earth elements (REEs) (La, Nd, Gd, Er) to Phalaris arundinacea were investigated. A soil dissolution experiment was conducted to elucidate the effect of citric acid and DFO-B at different concentrations (1 and 10 mmol L-1 citric acid) on the release of Ge and REEs from soil. In a greenhouse, plants of P. arundinacea were cultivated on soil and on sand cultures to investigate the effects of citric acid and DFO-B on the uptake of Ge and REEs by the plants. Addition of 10 mmol L-1 citric acid significantly enhanced desorption of Ge and REEs from soil and uptake into soil-grown plants. Applying DFO-B enhanced the dissolution and the uptake of REEs, while no effect on Ge was observed. In sand cultures, the presence of citric acid and DFO-B significantly decreased the uptake of Ge and REEs, indicating a discrimination of the formed complexes during uptake. This study clearly indicates that citric acid and the microbial siderophore DFO-B may enhance phytoextraction of Ge and REEs due to the formation of soluble complexes that increase the migration of elements in the rhizosphere.

Antioxidant and Antihypertensive Potential of Protein Fractions from Flour and Milk Substitutes from Canary Seeds (Phalaris canariensis L.).

Canary seed (Phalaris canariensis) is used to feed birds but it has been recently considered a promising cereal with nutraceutical potential for humans. The aim of this work was to analyze the protein fractions from canary seed flour and from milk substitutes (prepared by soaking the seeds in water 12 and 24 h), and to evaluate antioxidant and antihypertensive capacity of peptides obtained after in vitro digestion. Prolamins were the major protein fraction, followed by glutelins. After digestion, albumins and prolamins fractions from milks presented higher levels of peptides than flour, globulins showed more peptides in flour and glutelins were found in similar concentrations in all samples; 24 h milk prolamins had the highest concentration of peptides. Purification by high performance liquid chromatography (HPLC), sequencing of peptides, in vitro antioxidant ABTS (2,2'-azino-bis, 3-ethylbenzothiazoline-6-sulphonic acid) and DPPH (2,2-diphenyl-1-picrylhydrazyl) assays, and antihypertensive capacity (angiotensin converting enzyme (ACE) assay), indicated that peptides from canary seed prolamins were the most efficient compounds with antioxidant and antihypertensive activity. Canary seeds may be considered an accessible and cheap source to prepare milk substitutes with high contents of bioactive peptides with remarkable functional properties to promote better human health and healthy ageing.

Inhibition by Seeds of Phalaris canariensis Extracts of Key Enzymes Linked to Obesity.

CONTEXT: Obesity and its associated diseases are an increasing problem around the world. One hyperglycemic remedy is reduction of glucose absorption performed by suppressing digestion of carbohydrates and lipids through the use of inhibitors. Phalaris canariensis (P canariensis) is a species belonging to the Graminaceae family and is used in traditional medicine in Mexico for treatment of diabetes and obesity. OBJECTIVE: The aim of the study was to evaluate the effects of different extracts of the seeds of P canariensis on enzymes metabolizing fat and carbohydrates, obtained using 3 solvents. DESIGN: The seeds of P canariensis were extracted using hexane (ALH), chloroform (ALC), and methanol (ALM) and were investigated for their antiobesity potential. SETTING: This research was conducted in the Laboratory of Research of Natural Products in the School of Chemical Engineering at the National Polytechnic Institute and in the Research Laboratory of Enzymology in the National School of Biological Sciences. OUTCOME MEASURES: Different concentrations of the extracts were used to study the inhibition of enzymatic activity by porcine pancreatic α-amylase, with carbose as a positive control. The inhibitory activity of α-glucosidase was determined using the standard method with bovine serum albumin (BSA). Pancreatic lipase (PL) activity was measured by absorbance at 412 nm, and the data obtained were compared with orlistat. The PL activity was assessed using a second method measuring the rate of release of oleic acid from triolein. Lipoprotein lipase (LPL) activity was measured by released (3H)-oleic acid. Lipolytic activity in cultured, mouse, 3T3-Ll adipocytes was used as a measure of hormone-sensitive lipase activity. The inhibitory activity of rat intestinal sucrase was determined by measuring the glucose released. A Caco-2 cell assay determined the content of free glucose. RESULTS: The ALH extract of P canariensis showed potent inhibitory activity with IC50 values of 2.13 and 1.25 mg/mL as compared with α-amylase and α-glucosidase, respectively, and produced inhibition in rat intestinal sucrose. Further, the ALM extract showed significantly inhibitory effects against PL, LPL, and lipolysis of 3T3-LI adipocytes. CONCLUSIONS: The results provide evidence for the effects of the seeds of P canariensis for a retarded absorption of carbohydrates and lipids through the inhibition of enzymes that are related to obesity and diabetes mellitus type 2.