The potential use of Ricinus communis L. (Castor) stalks as a lignocellulosic resource for particleboards

Castor (Ricinus communis L.) stalks, which are a readily available by-product of this plant mainly cultivated for seed production, derived from experimental plantations grown in Northern Greece during the period April–October 1996 were assessed for their suitability as feed stocks for direct substitution of wood in particleboard. The average stalk yield of castor reached about 10 dry t/ha, which is higher than the average yield of forest in temperate zones. After harvesting, castor stalks were dried in a greenhouse to about 12% moisture content, and chipped by an automobile chipper and re-chipped in a hammermill. Castor particles and industrial wood particles mixed in various proportions were used as raw material for one-layer and for the middle layer of three-layer particleboards. A commercial E₂ grade UF-resin was used as binder. Castor particles were characterized by a lower slenderness ratio and lower bulk density than industrial wood particles. The evaluation of the mechanical and hygroscopic properties of panels showed the following results: Partial substitution of wood by castor stalks resulted in the deterioration of all board properties. The presence of the unlignified pith and the configuration of castor particles seem to be responsible for the deleterious effect of castor stalks on board properties. However, comparing the properties of the boards produced in this study to relevant European and American Standards, it was found that, with the exception of screwholding strength for three-layer boards, the experimental one layer-, and three-layer boards containing up to 25% and 75% castor particles respectively meet or exceed the Standards requirements for interior boards.     

Flaking as a corn preparation technique for dry-grind ethanol production using raw starch hydrolysis

A 2³ full-factorial study was designed to study the effect of corn preparation methods (flaking and grinding) on dry-grind ethanol performance using raw starch hydrolysis (RSH) process. Moisture content (15, 22%), flaker roller gapsetting (0.508 mm, 1.016 mm), and grinding were studied. Fifteen hundred g of corn samples were cracked, roller pressed, and were either ground further or retained, along with control ground corn. A bimodal size distribution was observed for ground corn, regardless of flaking. Moisture at 22% resulted in bigger-sized flakes with d₅₀ between ∼1.3 and 1.8 mm, compared to ∼138–169 μm for ground corn. Not all ground corn resulted in higher ethanol concentration in fermentation beer; the ethanol levels in beer did not reflect the starch hydrolysis trend that favored ground corn. In a related study, the beer ethanol concentration did not show a clear trend with rollermill gapsetting while fermenting the flakes produced at 0.203, 0.305, 0.406, and 0.508 mm gapsettings. Generally, flakes from corn at 22% moisture resulted in higher ethanol content in beer. Rollermill flaking was found comparable to hammermill grinding for dry-grind corn ethanol via raw starch hydrolysis and yeast fermentation.     

Optimization of formic/acetic acid delignification of Miscanthus × giganteus for enzymatic hydrolysis using response surface methodology

A Box-Behnken experimental design and response surface methodology were employed to optimize the pretreatment parameters of a formic/acetic acid delignification treatment of Miscanthus × giganteus for enzymatic hydrolysis. The effects of three independent variables, namely cooking time (1, 2 and 3 h), formic acid/acetic acid/water ratio (20/60/20, 30/50/20 and 40/40/20) and temperature (80, 90 and 107 °C) on pulp yield, residual Klason lignin content, concentration of degradation products (furfural and hydroxymethylfurfural) in the black liquor, and enzymatic digestibility of the pulps were investigated. The major parameter influencing was the temperature for pulp yield, delignification degree, furfural production and enzymatic digestibility. According to the response surface analysis the optimum conditions predicted for a maximum enzymatic digestibility of the glucan (75.3%) would be obtained using a cooking time of 3 h, at 107 °C and with a formic acid/acetic acid/water ratio of 40/40/20%. Glucan digestibility was highly dependent on the delignification degree.     

Tetrodotoxin (TTX) as a therapeutic agent for pain

Tetrodotoxin (TTX) is a potent neurotoxin that blocks voltage-gated sodium channels (VGSCs). VGSCs play a critical role in neuronal function under both physiological and pathological conditions. TTX has been extensively used to functionally characterize VGSCs, which can be classified as TTX-sensitive or TTX-resistant channels according to their sensitivity to this toxin. Alterations in the expression and/or function of some specific TTX-sensitive VGSCs have been implicated in a number of chronic pain conditions. The administration of TTX at doses below those that interfere with the generation and conduction of action potentials in normal (non-injured) nerves has been used in humans and experimental animals under different pain conditions. These data indicate a role for TTX as a potential therapeutic agent for pain. This review focuses on the preclinical and clinical evidence supporting a potential analgesic role for TTX. In addition, the contribution of specific TTX-sensitive VGSCs to pain is reviewed.     

A targeted QTL analysis for fiber length using a genetic population between two introgressed backcrossed inbred lines in upland cotton(Gossypium hirsutum)

Cotton fiber is the most important natural raw material for the textile industry, and fiber length(FL) is one of the most important traits in cotton.Quantitative trait locus(QTL)mapping based on high-density genetic maps is an efficient approach to identify genetic regions for FL.In our study, two backcrossed inbred lines(BILs) were chosen as parents to construct a high-density genetic map in F2 which was used to fine map FL QTL in F2:3 population.The genetic map had a total size of 3462.8 cM, containing 9182 singlenucleotide polymorphisms(SNPs) based on genotyping-by-sequencing.Two FL related stable QTL were identified on two chromosomes(qFL-A08–1 on A08 and qFL-D03–1 on D03),and qFL-A08–1 was confirmed by a meta-analysis.Utilizing previously obtained RNA-seq data for the two BILs and qRT-PCR analysis, two candidate genes annotated as cytochrome b5(CB5, Gh_A08 G1729) and microtubule end-binding 1 C(EB1C, Gh_D03 G0232) that may regulate FL during the fiber elongation stage were identified.In addition, nine recombination hotspots in this population were found.The results of this study will provide an important foundation for further studies on the molecular and genetic regulation of fiber elongation.     

Optimization of hydrolysis conditions for the production of angiotensin-I converting enzyme-inhibitory peptides and isolation of a novel peptide from lizard fish (Saurida elongata) muscle protein hydrolysate

Lizard fish (Saurida elongata) muscle protein was hydrolyzed using neutral protease to produce protein hydrolysate (LFPH), and the hydrolysis conditions were investigated using response-surface methodology. The optimum conditions for producing peptides with the highest angiotensin-I converting enzyme (ACE)-inhibitory activity were the following: enzyme-to-substrate ratio of 10,000 U/g, temperature of 48 °C, pH 7.0, and hydrolysis time of 2 h. Under these conditions, the ACE-inhibitory activity of LFPH and the degree of hydrolysis were 84% and 24%, respectively. A novel ACE-inhibitory peptide was isolated from LFPH using ultrafiltration, Sephadex G-15, and high-performance liquid chromatography. The amino acid sequence of the ACE-inhibitory peptide was identified as Ser-Pro-Arg-Cys-Arg (SPRCR), and its IC₅₀ was 41 ± 1 µM.     

Hygiene-Eliciting Brood Semiochemicals as a Tool for Assaying Honey Bee (Hymenoptera: Apidae) Colony Resistance to Varroa (Mesostigmata: Varroidae)

Despite numerous interventions, the ectoparasitic mite Varroa (Varroa destructor Anderson and Trueman [Mesostigmata: Varroidae]) and the pathogens it vectors remain a primary threat to honey bee (Apis mellifera Linnaeus [Hymenoptera: Apidae]) health. Hygienic behavior, the ability to detect, uncap, and remove unhealthy brood from the colony, has been bred for selectively for over two decades and continues to be a promising avenue for improved Varroa management. Although hygienic behavior is expressed more in Varroa-resistant colonies, hygiene does not always confer resistance to Varroa. Additionally, existing Varroa resistance selection methods trade efficacy for efficiency, because those achieving the highest levels of Varroa resistance can be time-consuming, and thus expensive and impractical for apicultural use. Here, we tested the hypothesis that hygienic response to a mixture of semiochemicals associated with Varroa-infested honey bee brood can serve as an improved tool for predicting colony-level Varroa resistance. In support of our hypothesis, we demonstrated that a mixture of the compounds (Z)-10-tritriacontene, (Z)-8-hentriacontene, (Z)-8-heptadecene, and (Z)-6-pentadecene triggers hygienic behavior in a two-hour assay, and that high-performing colonies (hygienic response to ≥60% of treated cells) have significantly lower Varroa infestations, remove significantly more introduced Varroa, and are significantly more likely to survive the winter compared to low-performing colonies (hygienic response to <60% of treated cells). We discuss the relative efficacy and efficiency of this assay for facilitating apiary management decisions and selection of Varroa-resistant honey bees, as well as the relevance of these findings to honey bee health, pollination services, and social insect communication.     

Tobacco stems as a low cost adsorbent for the removal of Pb(II) from wastewater: Equilibrium and kinetic studies

Adsorption of Pb(II) ions from aqueous solution onto tobacco stems has been investigated to evaluate the effects of initial lead ion concentration, adsorbent dosage, contact time, pH and temperature on the removal of Pb(II) systematically. The optimal pH value for Pb(II) adsorption onto the tobacco stems was found to be 5.0. The removal of lead ions for concentrations 10, 30 and 50 mg L⁻¹ using 0.8 g adsorbent at contact time of 120 min and at temperature of 299 K were 94.37%, 92.10% and 90.43%, respectively. Thermodynamic parameters such as standard Gibbs free energy (ΔG°), standard enthalpy (ΔH°), and standard entropy (ΔS°) were evaluated by applying the Van’t Hoff equation, which describes the dependence of equilibrium constant on temperature. The thermodynamics of Pb(II) adsorption onto the tobacco stems indicated that the adsorption was spontaneous and endothermic. Langmuir and Freundlich isotherms were used to analyze the equilibrium data at different temperatures and the equilibrium data were found to fit Freundlich isotherm equation better than Langmuir isotherm. The adsorption was analyzed using pseudo-second-order kinetic equation.     

Evaluation of tall fescue (Festuca arundinacea) as a forage for sheep in the temperate high‐rainfall zone of south‐eastern Australia

Tall fescue (Festuca arundinacea Schreb.) is currently seldom used in the high‐rainfall (>600 mm) zone of south‐eastern Australia. To determine its potential to improve forage availability during the summer‐autumn feed‐deficit period, a field plot‐scale experiment with sheep evaluated a Continental cultivar of tall fescue (cv. Quantum) at Hamilton, Victoria, between September 2006 and January 2009. Four grazing treatments represented set stocking or rotational grazing at the two‐, three‐ or four‐leaf stage, in a completely randomized design with three replications. Grazing treatment effects on tall fescue tiller population dynamics, forage accumulation rates and consumption, sward nutritive value and botanical composition were measured. Results showed tall fescue can persist and support year‐round grazing by sheep, subject to water availability for summer growth from summer rain or on moisture retentive heavy soils. During the summer‐autumn (December–April) vegetative phase, grazing at the three‐leaf stage optimized forage consumption, with no difference in feed value or botanical composition between the grazing treatments during these months. During the reproductive phase (September–November), feed value was highest under set stocking and declined with the production of each successive leaf. Grazing at the three‐ or four‐leaf stage prevented winter weed invasion, but winter forage consumption was low in these treatments. Set stocking or grazing at the two‐leaf stage improved winter forage consumption rates, but these swards were invaded by winter growing weeds.     

The combined use of hull-less barley flour and xylanase as a strategy for wheat/hull-less barley flour breads with increased arabinoxylan and (1→3,1→4)-β-D-glucan levels

Bread-making with a composite flour (CF) consisting of 60% wheat flour (WF) and 40% hull-less barley flour, increased the total and soluble (1→3,1→4)-β-D-glucan and total arabinoxylan (AX) contents of dough and bread samples, but decreased the specific bread loaf volume. A xylanase insensitive to inhibition by Triticum aestivum L. xylanase inhibitor (TAXI) and xylanase inhibiting protein (XIP), increased loaf volume by 8.8 and 20.1% for WF and CF breads, respectively. Xylanase addition not only markedly improved loaf volume of CF bread, but also increased the soluble AX content of the WF and CF dough and bread samples because of conversion of water-unextractable AX into soluble AX. The xylanase had no impact on the extractability and molecular weight of (1→3,1→4)-β-D-glucan, but (1→3,1→4)-β-D-glucan was degraded during bread-making probably because of endogenous β-glucanase activity. Taken together, the results clearly show that the combined use of hull-less barley flour and a xylanase active during bread making, lead to palatable breads with high total and soluble AX and (1→3,1→4)-β-D-glucan contents. The sum of total AX and (1→3,1→4)-β-D-glucan was 1.70% for WF bread and 3.06% for CF bread, while the sum of soluble AX and (1→3,1→4)-β-D-glucan was 0.49 and 1.41% for control WF and CF xylanase supplemented breads, respectively.