Resource-use,body condition and parasite load metrics indicate contrasting health of stocked and native game fishes in Canadian prairie lakes

This study evaluated the status of native and stocked fish species in 13 prairie lakes in central Canada over eight years (2007–14) using three metrics: resource-use (benthic versus pelagic carbon via stable isotopes); body condition (relative weight index W_r); and parasite load (cestode gut enumerations). Analyses included game and non-game fishes, like naturally occurring northern pike, Esox lucius L., and yellow perch, Perca flavescens Mitchill, but focused on stocked walleye, Sander vitreus (Mitchill) because it supports a robust recreational fishery. Walleye and northern pike were significantly more reliant on benthic carbon than yellow perch or forage fishes (p < 0.05), but this reliance was not associated with any measured environmental variables for any species. In lakes with game fishes, forage fishes exhibited higher reliance on benthic energy, possibly due to predator avoidance strategy, particularly yellow perch. Walleye body condition index was consistently lower (<95–105) than values exhibited by the other two game fishes (81–139), and parasites were only common in walleye and associated with lake-water salinity (r² = 0.93, p < 0.05) and sex (p < 0.05). Based on the results, the most desirable game fish, walleye, appears less resilient to environmental variability than northern pike and yellow perch, making this species more susceptible to impacts of future climate change.     

Lignification in cell cultures of Pinus radiata: activities of enzymes and lignin topochemistry

Enzymatic and topochemical aspects of lignification were studied in a Pinus radiata D. Don cell culture system that was induced to differentiate tracheary elements and sclereids with lignified secondary cell walls. The activities of the lignin-related enzymes phenylalanine ammonia lyase (PAL; EC 4.3.1.5) and cinnamyl alcohol dehydrogenase (CAD; EC 1.1.1.195) increased concomitantly with cell differentiation, indicating that the increase in enzyme activity was related to lignification of the cell walls and was not induced by stress. This result also indicates that PAL and CAD are suitable markers for tracheary element differentiation in coniferous gymnosperms. To further characterize lignification in this cell culture system, cellular UV-microspectrophotometry and thioacidolysis were employed. Typical UV-absorption spectra of lignin were obtained from the secondary cell walls of the tracheary elements and sclereids and from the compound middle lamella connecting differentiated cells, and the presence of lignin was confirmed by thioacidolysis. Certain aspects of lignin topochemistry in the cell walls of the tracheary elements were similar to cell walls of P. radiata wood, such as the high lignin concentration in the compound middle lamella connecting adjacent cells and the lower lignin concentration in the secondary cell walls. Therefore, the P. radiata cell culture system appears to be well suited to study the formation of lignified secondary cell walls in coniferous gymnosperms.     

Portable acoustic device for detection of coconut palms infested by Rynchophorus ferrugineus (Coleoptera: Curculionidae)

Acoustic methods have been developed and used to detect insects in concealed habitats. The larvae of red palm weevil, Rynchophorus ferrugineus (Olivier), a serious pest of the coconut palm, Cocos nucifera L. feed on the soft tissues inside the stem and bud region. Detection of infested coconut palms in the early stages by the conventional method of checking for external symptoms is time consuming, labour intensive and costly. This paper describes the development of a portable and efficient acoustic device and its potential in detection of infested palms in the field. The device comprises a sensor to mount on the palm and to acquire the sounds of red palm weevil larvae, an electronic unit that processes the acquired sounds and a set of headphones to receive the output sound by the listener. It is light weight, user-friendly and powered by batteries. The highest accuracy of identifying infested palms was obtained when the palm was checked at four positions; either side of palm base and bases of the two lowermost leaves. The infested palms were detected with over 97% accuracy, while the probability of not detecting uninfested palms was over 92%. A second check increased the rate of accuracy. Many difficulties encountered with conventional methods could be overcome by the use of this device.     

Understanding the degree of condensation of phenolic and etherified C-9 units of in situ lignins

A novel approach for the quantification of the degree of condensation at the C(5) position of etherified and phenolic phenylpropane (C-9) units of in situ lignin is described. This is achieved by degrading unmethylated and methylated wood by thioacidolysis and analyzing the resultant product mixtures by quantitative (31)P NMR spectroscopy. Applying this new method to compression wood and normal wood from Pinus radiata showed that, whereas 41-47% of etherified guaiacyl C-9 units are condensed at the C(5) position, almost all phenolic guaiacyl C-9 units exist as uncondensed moieties. Analysis of milled wood lignin (MWL) isolated from the same wood by (31)P NMR spectroscopy before and after thioacidolysis showed that the phenolic guaiacyl C-9 units were more condensed than those in the in situ lignin. This is likely due to partial cleavage of the more condensed etherified linkages during the lignin isolation, leading to a relative increase in condensed phenolic guaiacyl C-9 units.     

Synthesis of water-soluble 9,10-anthraquinone analogues with potent cyanobactericidal activity toward the musty-odor cyanobacterium Oscillatoria perornata

A series of water-soluble 9,10-anthraquinone analogues were prepared and evaluated for their selective toxicity toward Oscillatoria perornata, which grows in catfish production ponds and causes "musty" off-flavor in channel catfish ( Ictalurus punctatus). Water-soluble mono- and dicationic salts were prepared by conjugating various small amines directly or through a methylene or ethylene bridge to the 9,10-anthraquinone nucleus. One of the dicationic salts, 2-[ N-(1'-methyl-4'- N, N-diethylaminobutyl)aminometyl]anthraquinone diphosphate, exhibited very high water solubility and potent selective toxicity toward O. perornata. However, the tendency of this compound to potentially bind to suspended sediments may be the reason for its limitations in controlling O. perornata in catfish production ponds. The monocationic salt, 2-[ N-(1'-methylethyl)]aminomethyl]anthraquinone monophosphate, showed good solubility and high selective toxicity toward O. perornata. Neutral water-soluble analogues prepared by conjugating terta- or pentaethylene glycol directly or by a methylene bridge to the 9,10-anthraquinone nucleus had less activity than the parent compound.     

In vitro antileishmanial, antiplasmodial and cytotoxic activities of phenolics and triterpenoids from Baccharis dracunculifolia D. C. (Asteraceae)

Baccharis dracunculifolia (Asteraceae), the most important plant source of the Brazilian green propolis (GPE), displayed in vitro activity against Leishmania donovani, with an IC₅₀ value of 45 µg/mL, while GPE presented an IC₅₀ value of 49 µg/mL. Among the isolated compounds of B. dracunculifolia, ursolic acid, and hautriwaic acid lactone showed IC₅₀ values of 3.7 µg/mL and 7.0 µg/mL, respectively. Uvaol, acacetin, and ermanin displayed moderate antileishmanial activity. Regarding the antiplasmodial assay against Plasmodium falciparum, BdE and GPE gave similar IC₅₀ values (about 20 µg/mL), while Hautriwaic acid lactone led to an IC₅₀ value of 0.8 µg/mL (D6 clone).     

Population Growth of Myzus persicae on Potato Plants Infected with Different Strains and Variants of Potato virus Y

Potato virus Y (PVY) is one of the most economically important viruses affecting the potato crop. Several strains of the virus, including PVY^O, PVY^N, recombinant isolates; PVY^N:O (PVY ^N-Wi) and PVY^NTN and several variants of PVY^O have been reported from North American potato-production areas. The green peach aphid, Myzus persicae Sulzer, is a colonizer of potatoes and is considered the most important vector of PVY. The objective of this study was to measure the population growth of M. persicae on potato plants infected with different strains and genetic variants of PVY. The initial population of ten winged adults of M. persicae was allowed to develop on a potted plant for 12 days. Results clearly indicated that infections by different strains and genetic variants of PVY did not influence the population growth of M. persicae on potato plants during this period.     

A novel technique for non-damaging measurement of sound speed in seedlings

A cross-correlation time-of-flight method for measuring the sound speed in a seedling in a non-destructive and non-damaging way is described. The method uses two miniature accelerometers coupled to the bark of a growing seedling stem to record the acoustic signals and a small striker to generate an acoustic pulse. The two acoustic signals are then time-windowed and cross-correlated in order to calculate the speed of the acoustic pulse. The method measures the sound speed of the seedling stem as a whole and does not selectively measure the fastest path. The method was tested on 1- and 2-year-old Pinus radiata clones. A comparison of the results of the method with a destructive acoustic resonance test showed that the sound speed results are unbiased. Repeatability tests give a standard deviation of the sound speed of less than 2%. The method shows good promise as a rapid and cost-effective tool for early screening of wood quality in clonal trials.     

Anti-Inflammatory Effects of Sulfated Polysaccharide from Sargassum swartzii in Macrophages via Blocking TLR/NF-Κb Signal Transduction

This study involves enzymatic extraction of fucoidan from Sargassum swartzii and further purification via ion-exchange chromatography. The chemical and molecular characteristics of isolated fucoidan is evaluated concerning its anti-inflammatory potential in RAW 264.7 macrophages under LPS induced conditions. Structural properties of fucoidan were assessed via FTIR and NMR spectroscopy. NO production stimulated by LPS was significantly declined by fucoidan. This was witnessed to be achieved via fucoidan acting on mediators such as iNOS and COX-2 including pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β), with dose dependent down-regulation. Further, the effect is exhibited by the suppression of TLR mediated MyD88, IKK complex, ultimately hindering NF-κB and MAPK activation, proposing its therapeutic applications in inflammation related disorders. The research findings provide an insight in relation to the sustainable utilization of fucoidan from marine brown algae S. swartzii as a potent anti-inflammatory agent in the nutritional, pharmaceutical, and cosmeceutical sectors.