Novel amphiphilic temperature responsive graft copolymers PCL-<Emphasis Type="Italic">g</Emphasis>-P(MEO<Subscript>2</Subscript>MA-<Emphasis Type="Italic">co</Emphasis>-OEGMA) via a combination of ROP and ATRP: synthesis,characterization, and sol-gel transition

A series of well-defined novel amphiphilic temperature-responsive graft copolymers containing PCL analogues P(αClεCL-co-εCL) as the hydrophobic backbone, and the hydrophilic side-chain PEG analogues P(MEO₂MA-co-OEGMA), designated as P(αClεCL-co-εCL)-g-P(MEO₂MA-co-OEGMA) have been prepared via a combination of ring-opening polymerization (ROP) and atom transfer radical polymerization (ATRP). The composition and structure of these copolymers were characterized by ¹H NMR and GPC analyses. The self-assembly behaviors of these amphiphilic graft copolymers were investigated by UV transmittance, a fluorescence probe method, dynamic light scattering (DLS) and transmission electron microscopy (TEM) analyses. The results showed that the graft copolymers exhibited the good solubility in water, and was given the low critical temperature (LCST) at 35(±1) °C, which closed to human physiological temperature. The critical micelle concentrations (CMC) of P(αClεCL-co-εCL)-g-P(MEO₂MA-co-OEGMA) in aqueous solution were investigated to be 2.0 × 10^?3, 9.1 × 10^?4 and 1.5 × 10^?3 mg·mL^?1, respectively. The copolymer could self-assemble into sphere-like aggregates in aqueous solution with diverse sizes when changing the environmental temperature. The vial inversion test demonstrated that the graft copolymers could trigger the sol-gel transition which also depended on the temperature.     

Efficacy of heat-killed <Emphasis Type="Italic">Lactococcus lactis</Emphasis> JCM 5805 on immunity and fatigue during consecutive high intensity exercise in male athletes: a randomized,placebo-controlled,double-blinded trial

Background

Lactococcus lactis JCM 5805 (LC-Plasma) is a unique lactic acid bacteria (LAB) which activates plasmacytoid dendritic cells (pDC). We aimed to evaluate the effect of LC-Plasma on dendritic cell (DC) activity and subjective indices of upper respiratory tract infections (URTI) and fatigue in athletes under high intensity exercise.

Methods

We conducted a randomized, placebo-controlled, double-blinded trial. Fifty-one male subjects belonging to a university sports club were randomized into placebo (n?=?25) and LC-Plasma (n?=?26) groups. Individuals ingested placebo capsules containing cornstarch or LC-Plasma capsules containing 100 billion cells of heat-killed LC-Plasma per day for 13 days. During the intervention period, subjects performed high intensity exercise according to their sports club training regime. Blood and saliva sampling were obtained at days 1 and 14, and physical conditions were recorded in a diary. We investigated expression of maturation markers on DCs, muscle damage and stress markers and used student’s t test adjusted by Bonferoni’s method for multiple comparison between groups. These data were presented as mean?±?SD. We also investigated cumulative days of symptoms regarding infections and fatigue and used Chi-square test for comparison between groups. These data were presented as cumulative number.

Results

CD86 as maturation marker on pDC was significantly increased in the LC-Plasma group at day 14 (Placebo: 296?±?70 vs. LC-Plasma: 365?±?115; Mean Fluorescent Intensity; p?=?0.013). Cumulative days of URTI were significantly lower in the LC-Plasma group (Placebo: URTI positive 56, URTI negative 256 vs. LC-Plasma: URTI positive 39, URTI negative 299; days; p?=?0.028) and symptoms like sneeze or running nose were significantly lower in the LC-Plasma group (Placebo: Symptom positive 52, Symptom negative 258, vs. LC-Plasma: Symptom positive 36, Symptom negative 301; days; p?=?0.032). Moreover, the cumulative days of fatigue were significantly fewer in the LC-Plasma group (Placebo: Symptom positive 128, Symptom negative 182, vs. LC-Plasma: Symptom positive 110, Symptom negative 225; days; p?=?0.032). Markers of muscle damage and stress markers were not significantly different between groups.

Conclusion

We consider that heat-killed LC-Plasma supplementation relieves morbidity and symptoms of URTI via activation of pDC and decreases fatigue accumulation during consecutive high intensity exercise in athletes. However, LC-Plasma ingestion did not affect markers of muscle damage and stress.

Trial registration

UMIN-CTR, UMIN000020372. Registered 28 December 2015.

     

<Emphasis Type="Italic">Brassica rapa</Emphasis> var. <Emphasis Type="Italic">japonica</Emphasis> Leaf Extract Mediated Green Synthesis of Crystalline Silver Nanoparticles and Evaluation of Their Stability,Cytotoxicity and Antibacterial Activity

Silver nanoparticles (AgNPs) were successfully synthesized from the reduction of Ag⁺ using AgNO₃ solution as a precursor and Brassica rapa var. japonica leaf extract as a reducing and capping agent. This study was aimed at synthesis of AgNPs, exhibiting less toxicity with high antibacterial activity. The characterization of AgNPs was carried out using UV–Vis spectrometry, energy dispersive X-ray spectrometry, fourier transform infrared spectrometry, field emission scanning electron microscopy, X-ray diffraction, atomic absorption spectrometry, and transmission electron microscopy analyses. The analyses data revealed the successful synthesis of nano-crystalline Ag possessing more stability than commercial AgNPs. The cytotoxicity of Brassica AgNPs was compared with commercial AgNPs using in vitro PC12 cell model. Commercial AgNPs reduced cell viability to 23% (control 97%) and increased lactate dehydrogenase activity at a concentration of 3 ppm, whereas, Brassica AgNPs did not show any effects on both of the cytotoxicity parameters up to a concentration level of 10 ppm in PC12 cells. Moreover, Brassica AgNPs exhibited antibacterial activity in terms of zone of inhibition against E. coli (11.1?±?0.5 mm) and Enterobacter sp. (15?±?0.5 mm) which was higher than some previously reported green-synthesised AgNPs. Thus, this finding can be a matter of interest for the production and safe use of green-AgNPs in consumer products.     

<Emphasis Type="SmallCaps">d</Emphasis>-Maltose Synthesized Silver Nanoparticles for Biofilm Eradication

Biofilms are complex bacterial communities have a mechanism for antibiotic resistance leading to human health problems. It remains challenging to treat and eradicate biofilms. In this work, the use of d-maltose synthesized silver nanoparticles (AgNPs) was investigated in an effort to eradicate a biofilm. AgNPs were synthesized using a modified Tollen’s method. d-maltose was used in synthesizing AgNPs with different concentrations of d-maltose (0.01, 0.05 and 0.1 M), referred to as NP1, NP2 and NP3, respectively. TEM images revealed that the particles were polygon shaped. The particle sizes were found to be 86.81?±?13.39, 54.94?±?11.63 and 31.43?±?31.76 nm depending on their sugar concentrations. UV–Vis, ATR–FTIR, and XRD patterns were employed to characterize the AgNPs. Then, these AgNPs were investigated for their anti-bacterial effects against Escherichia coli and Staphylococcus aureus. Evaluation of the minimum inhibitory concentration and minimal bactericidal concentration revealed that S. aureus was inhibited by all AgNPs and killed by NP1 and NP3, and E. coli was inhibited and killed at all AgNPs doses. Furthermore, anti-biofilm activity against these two bacteria was observed using SEM and confocal laser scanning microscopy. This sugar coated AgNPs is a promising material for use in eradication of biofilms.     

One Pot Synthesis and Properties of Cationic Surfactants: <Emphasis Type="Italic">n</Emphasis>-Alkyl-3-Methylpyridinium Bromide

Three new amphiphilic compounds i.e., n-decyl-3-methylpyridinium bromide (a), n-dodecyl-3-methylpyridinium bromide (b), and n-tetradecyl-3-methylpyridinium bromide (c), have been synthesized by condensation reaction and characterized by NMR (¹H, ¹³C) and FTIR spectroscopic techniques. The micellization behavior of the compounds has been studied in ethanol employing conductometry and UV/visible spectroscopy. The critical micellization concentration (CMC) values for compound a, b and c was found to be 0.31, 0.29 and 0.27 m mol L^?1, respectively. Effect of temperature on the CMC was checked in the range of 298-318 K. The thermodynamic parameters such as ΔG, ΔH and ΔS of the micellization process of these surfactants were computed. The negative values of ΔG and positive values of ΔH indicated the spontaneous and endothermic nature of the micellization process. Antimicrobial activities of these amphiphiles showed significant activity against different bacterial strains.     

2-Methoxylated FA Display Unusual Antibacterial Activity Towards Clinical Isolates of Methicillin-Resistant <Emphasis Type="Italic">Staphylococcus aureus</Emphasis> (CIMRSA) and <Emphasis Type="Italic">Escherichia coli</Emphasis>

The naturally occurring (6Z)-(±)-2-methoxy-6-hexadecenoic acid (1) and (6Z)-(±)-2-methoxy-6-octadecenoic acid (2) were synthesized in 7–8 steps with 38 and 13% overall yields, respectively, by using an acetylide coupling approach, which made it possible to obtain a 100% cis-stereochemistry for the double bonds. In a similar fashion, the acetylenic analogs (±)-2-methoxy-6-hexadecynoic acid (3) and (±)-2-methoxy-6-octadecynoic acid (4) were also synthesized in 6–7 steps with 48 and 16% overall yields, respectively. The antibacterial activity of acids 1–4 was determined against clinical isolates of methicillin-resistant Staphylococcus aureus (ClMRSA) and Escherichia coli. Among the series of compounds, acid 4 was the most active bactericide towards CIMRSA displaying IC_50s (half maximal inhibitory concentrations) between 17 and 37 μg/mL, in sharp contrast to the 6-octadecynoic acid, which was not bactericidal at all. On the other hand, acids 1 and 3 were the only acids that displayed antibacterial activity towards E. coli, but 1 stood out as the best candidate with an IC₅₀ of 21 μg/mL. The critical micelle concentrations (CMCs) of acids 1–4 were also determined. The C18 acids 2 and 4 displayed a five-fold lower CMC (15–20 μg/mL) than the C16 analogs 1 and 3 (70–100 μg/mL), indicating that 4 exerts its antibacterial activity in a micellar state. None of the studied acids were inhibitory towards S. aureus DNA gyrase discounting this type of enzyme inhibition as a possible antibacterial mechanism. It was concluded that the combination of α-methoxylation and C-6 unsaturation increases the bactericidal activity of the C16 and C18 FA towards the studied bacterial strains. Acids 1 and 4 stand out as viable candidates to be used against E. coli and CIMRSA, respectively.     

Atmospheric nitrogen loss factor (<Emphasis Type="Italic">f</Emphasis>) used in determining nitrogen-based municipal wastewater effluent irrigation rates: design and nitrogen-balance estimated <Emphasis Type="Italic">f</Emphasis> values

Design irrigation rates for treated municipal wastewater effluent (MWE) are usually determined from nitrogen (N) mass-balances, in which the fraction (f) of the total N in the MWE that is lost to the atmosphere is commonly obtained from US Environmental Protection Agency (USEPA) tabulated (design) values: 0.15–0.25 for secondary-treated effluents and 0.1 for tertiary-treated effluents. In 2011 and 2012, f values from an N balance in a tall fescue (Festuca arundinacea Schreb.) hay field in Central Pennsylvania were quantified and compared to the USEPA design f values. The grass field was spray-irrigated with MWE (C:N ratio = 0.04–0.2; near neutral pH, and 70–87% of the MWE-TN was NO₃–N) at a rate of ≤5-cm wk^?1. Monthly N balances were calculated from April to September in the surface horizon of a Hagerstown soil. The f values of 0.05, 0.1, and 0.2 seemed appropriate for the months of May and June, August and September, and July, respectively. Positive fnb estimates and the logarithm of measured monthly N removal in the aboveground biomass (kg ha^?1) were negatively correlated (R² = 0.99 for monthly mean air temperatures ≥20 °C and R² = 0.2 for monthly mean air temperatures <20 °C). The study’s results suggest that existing design f values are likely less applicable especially due to the biological N-removal processes currently present in many wastewater treatment plants needing to meet effluent N limits. Thus, more studies to determine empirical f values in effluent irrigation are needed to refine design f values.     

Bioengineering functional copolymers: synthesis and characterization of poly(<Emphasis Type="Italic">N</Emphasis>-isopropyl acrylamide-<Emphasis Type="Italic">co</Emphasis>-3,4-2H-dihydropyran)s

Novel bioengineering copolymers were synthesized by radical copolymerization of N-isopropylacrylamide (NIPA) and 3,4-2H-dihydropyran (DHP) with 2,2′-azobisisobutyronitrile as an initiator in acetone solution at 70 °C under nitrogen atmosphere. Structure, tacticity and compositons of the copolymers prepared in a wide range of monomer feed were confirmed by FTIR, ¹H{¹³C} NMR-DEPT and elemental analyses. The monomer reactivity ratios (r ₁ and r ₂) were detected using known two methods: r ₁ (NIPA)?=?1.25 and r ₂?=?0.035 (DHP), and r ₁ (NIPA) ?=?0.97 and r ₂?=?0.022 (DHP) by Kelen-Tüdös and Jaacks methods, respectively. It was demonstrated that the studied monomer pair has a tendency to form H-bonding beween amide/ether groups through ?NH...O< complexation which played an important role in the stereoselective chain growth, and significant decrease of allyl degradative chain transfer reactions. This phenomenon is also confirmed by the observed relatively high molecular weights of copolymers (M _v ). The synthesized water-soluble stimuli-responsive poly(NIPA-co-DHP)s exhibit thermal stability, higher glass-transition temperature, polyelectrolyte, pH- and temperature-sensitive behavior and can be attributed to the class of bioengineering functional copolymers useful for various bio- and gene-engineering, and drug delivery applications.     

Synthesis and swelling behavior of metal-chelating superabsorbent hydrogels based on sodium alginate-<Emphasis Type="Italic">g</Emphasis>-poly(AMPS-<Emphasis Type="Italic">co</Emphasis>-AA-<Emphasis Type="Italic">co</Emphasis>-AM) obtained under microwave irradiation

A metal-chelating superabsorbent hydrogel based on poly(2-acrylamido-2-methylpropanesulfonic acid-co-acrylic acid-co-acrylamide) grafted onto sodium alginate backbone, NaAlg-g-poly(AMPS-co-AA-co-AM) is prepared under microwave irradiation. The Taguchi method is used for the optimization of synthetic parameters of the hydrogel based on water absorbency. The Taguchi L₉ (3⁴) orthogonal array is chosen for experimental design. Mass concentrations of crosslinker MBA \(C_{\text{MBA}}\) initiator KPS \(C_{\text{KPS}}\), sodium alginate \(C_{\text{NaAlg}}\) and mass ratio of monomers \(C_{\text{AM/AA/AMPS}}\) are chosen as four factors. The analysis of variance of the test results indicates the following optimal conditions: 0.8 g L^?1 of MBA, 0.9 g L^?1 of KPS, 8 g L^?1 of NaAlg and \(R_{\text{AM/AA/AMPS}}\) equals to 1:1.1:1.1. The maximum water absorbency of the optimized final hydrogel is found to be 822 g g^?1. The relative thermal stability of the optimized hydrogel in comparison with sodium alginate is demonstrated via thermogravimetric analysis. The prepared hydrogel is characterized by FTIR spectroscopy and scanning electron microscopy. The influence of the environmental parameters on water absorbency such as the pH and the ionic force is also investigated. The optimized hydrogel is used as adsorbent for hazardous heavy metal ions Pb(II), Cd(II), Ni(II) and Cu(II) and their competitive adsorption is also discussed. Isotherm of adsorption and effect of pH, adsorption dosage and recyclability are investigated. The results show that the maximum adsorption capacities of lead and cadmium ions on the hydrogel are 628.93 and 456.62 mg g^?1, respectively. The adsorption is well described by Langmuir isotherm model. The hydrogel is also utilized for the loading of potassium nitrate as an active agrochemical agent and the release of this active agent has also been investigated.     

Synthesis,characterization and thermal dehydration and degradation kinetics of chitosan Schiff bases of <Emphasis Type="Italic">o</Emphasis>-, <Emphasis Type="Italic">m</Emphasis>- and <Emphasis Type="Italic">p</Emphasis>-nitrobenzaldehyde

The chitosan Schiff bases were synthesised through the condensation reaction of chitosan with o-, m- and p-nitrobenzaldehyde (abbreviated as CSB-o, CSB-m and CSB-p) in the ratio 1:1 and were characterised by means of FTIR, UV, XRD and SEM. The thermal dehydration and degradation kinetics of all these Schiff bases were studied using different isoconversional and maximum rate (peak) methods, viz. Kissinger–Akahira–Sunose (KAS), Tang, Starink, Flynn–Wall–Ozawa (FWO) and Bosewell from DSC data and the thermal stability from TG. The activation energy values of thermal dehydration and degradation reactions obtained from isoconversional methods of FWO and Bosewell are slightly higher than that obtained from other methods. All the isoconversional and maximum rate (peak) methods yielded consistent values of E _α for both the dehydration and degradation reactions and is in the order CSB-o < CSB-m < CSB-p. The Schiff bases observed (from TG) the same order of thermal stability.     

Enhanced Thermoelectric Performance of <Emphasis Type="Italic">c</Emphasis>-Axis-Oriented Epitaxial Ba-Doped BiCuSeO Thin Films

We reported the epitaxial growth of c-axis-oriented Bi_1?xBa_xCuSeO (0?≤ x ≤?10%) thin films and investigated the effect of Ba doping on the structure, valence state of elements, and thermoelectric properties of the films. X-ray photoelectron spectroscopy analysis reveal that Bi³⁺ is partially reduced to the lower valence state after Ba doping, while Cu and Se ions still exist as +?1 and ??2 valence state, respectively. As the Ba doping content increases, both resistivity and Seebeck coefficient decrease because of the increased hole carrier concentration. A large power factor, as high as 1.24 mWm^?1 K^?2 at 673 K, has been achieved in the 7.5% Ba-doped BiCuSeO thin film, which is 1.5 times higher than those reported for the corresponding bulk samples. Considering that the nanoscale-thick Ba-doped films should have a very low thermal conductivity, high ZT can be expected in the films.     

Inhibitory Effects of Semiochemicals on the Attraction of an Ambrosia Beetle <Emphasis Type="Italic">Euwallacea</Emphasis> nr. <Emphasis Type="Italic">fornicatus</Emphasis> to Quercivorol

The Euwallacea fornicatus (Eichhoff) species complex includes the polyphagous shot hole borer (PSHB), an ambrosia beetle infesting avocado limbs, Persea americana Mill. Synthetic quercivorol, a monoterpene alcohol, is known to attract females (males are flightless) over a range of release rates spanning three orders of magnitude. The upper release dose was extended 10-fold using sticky traps baited with quercivorol released at 1× (0.126 mg/day), 10×, and 108× relative rates to obtain a dose?response curve fitting a kinetic formation function. Naturally infested limbs of living avocado trees were wrapped with netting to exclude the possibility of catching emerging beetles on the encircling sticky traps. The results indicate PSHB are significantly attracted to infested limbs. Ethanol released over a 64-fold range (lowest rate of 7.5 mg/day) was moderately inhibitory of PSHB attraction to 1× quercivorol. β-caryophyllene and eucalyptol did not appear to affect attraction at the rates tested. A field test of potential inhibitors of 1× quercivorol was done using ~1 mg/day releases of monoterpene ketones: (?)-(S)-verbenone, (+)-(R)-verbenone, 3-methyl-2-cyclo-hexen-1-one (MCH or seudenone), piperitone, (+)-(S)-carvone, and racemic cryptone. Only piperitone and the two enantiomers of verbenone were strongly inhibitory. A blend of piperitone and verbenone tested together at different distances (0, 0.5, 1, 2, and 4 m) from a 1× quercivorol baited sticky trap became increasingly ineffective in inhibiting the attractant as separation distance increased. Due to the relatively short-range repellency (<1 m), the inhibitors would need to be released from several places on each tree to effectively repel PSHB from avocado trees. Effective attraction radii, EAR, and circular EARc are estimated for the quercivorol baits released at 1×, 10× and 108× rates. Push-pull simulations of moving beetles were performed in 1 ha plots with 2, 4, or 16 traps of 10× EARc and 400 trees (0, 1, or 3 inhibitors per tree) of which ten had an infested limb (EARc?=?0.5 m). The simulations indicate that push-pull methods would be more effective in reducing PSHB mating than simply using mass-trapping alone.     

Ammonia Released by <Emphasis Type="Italic">Streptomyces aburaviensis</Emphasis> Induces Droplet Formation in <Emphasis Type="Italic">Streptomyces violaceoruber</Emphasis>

Streptomyces violaceoruber grown in co-culture with Streptomyces aburaviensis produces an about 17-fold higher volume of droplets on its aerial mycelium than in single-culture. Physical separation of the Streptomyces strains by either a plastic barrier or by a dialysis membrane, which allowed communication only by the exchange of volatile compounds or diffusible compounds in the medium, respectively, still resulted in enhanced droplet formation. The application of molecular sieves to bioassays resulted in the attenuation of the droplet-inducing effect of S. aburaviensis indicating the absorption of the compound. ¹H-NMR analysis of molecular-sieve extracts and the selective indophenol-blue reaction revealed that the volatile droplet-inducing compound is ammonia. The external supply of ammonia in biologically relevant concentrations of ≥8 mM enhanced droplet formation in S. violaceoruber in a similar way to S. aburaviensis. Ammonia appears to trigger droplet production in many Streptomyces strains because four out of six Streptomyces strains exposed to ammonia exhibited induced droplet production.     

Itaconic Acid Based Surfactants: I. Synthesis and Characterization of Sodium <Emphasis Type="Italic">n</Emphasis>-Octyl Sulfoitaconate Diester Anionic Surfactant

A novel itaconate-based surfactant, namely sodium n-octyl sulfoitaconate diester (SOSID), has been synthesized from itaconic acid (IA) and n-octanol by sulfonation and esterification reaction processes. The effects of reaction temperature, reaction time, molar ratios of n-octanol to IA and the catalyst dosage on the esterification were investigated. The chemical structure of the surfactants SOSID was characterized by means of LC–MS and confirmed by FT-IR and ¹H NMR spectroscopy. The surface tension γ and the critical micelle concentration (CMC) were determined as 25.02 mN/m and 4.0 × 10^?4 mol/L by using surface tensiometer at 20 °C. Further investigations showed that SOSID possess excellent wetting, emulsifying and lime soap dispersing properties.     

Oxidizable Phenolic Concentrations Do Not Affect Development and Survival of <Emphasis Type="Italic">Paropsis Atomaria</Emphasis> Larvae Eating <Emphasis Type="Italic">Eucalyptus</Emphasis> Foliage

Insect folivores can cause extensive damage to plants. However, different plant species, and even individuals within species, can differ in their susceptibility to insect attack. Polyphenols that readily oxidize have recently gained attention as potential defenses against insect folivores. We tested the hypothesis that variation in oxidizable phenolic concentrations in Eucalyptus foliage influences feeding and survival of Paropsis atomaria (Eucalyptus leaf beetle) larvae. First we demonstrated that oxidizable phenolic concentrations vary both within and between Eucalyptus species, ranging from 0 to 61 mg.g^?1 DM (0 to 81% of total phenolics), in 175 samples representing 13 Eucalyptus species. Foliage from six individuals from each of ten species of Eucalyptus were then offered to batches of newly hatched P. atomaria larvae, and feeding, instar progression and mortality of the first and second instar larvae were recorded. Although feeding and survival parameters differed dramatically between individual plants, they were not influenced by the oxidizable phenolic concentration of leaves, suggesting that P. atomaria larvae may have effective mechanisms to deal with oxidizable phenolics. Larvae feeding on plants with higher nitrogen (N) concentrations had higher survival rates and reached third instar earlier, but N concentrations did not explain most of the variation in feeding and survival. The cause of variation in eucalypt herbivory by P. atomaria larvae is therefore still unknown, although oxidizable phenolics could potentially defend eucalypt foliage against other insect herbivores.     

Sexual Deception in the <Emphasis Type="Italic">Eucera</Emphasis>-Pollinated <Emphasis Type="Italic">Ophrys leochroma</Emphasis>: A Chemical Intermediate between Wasp- and <Emphasis Type="Italic">Andrena-</Emphasis>Pollinated Species

Ophrys flowers mimic sex pheromones of attractive females of their pollinators and attract males, which attempt to copulate with the flower and thereby pollinate it. Virgin females and orchid flowers are known to use the same chemical compounds in order to attract males. The composition of the sex pheromone and its floral analogue, however, vary between pollinator genera. Wasp-pollinated Ophrys species attract their pollinators by using polar hydroxy acids, whereas Andrena-pollinated species use a mixture of non-polar hydrocarbons. The phylogeny of Ophrys shows that its evolution was marked by episodes of rapid diversification coinciding with shifts to different pollinator groups: from wasps to Eucera and consequently to Andrena and other bees. To gain further insights, we studied pollinator attraction in O. leochroma in the context of intra- and inter-generic pollinator shifts, radiation, and diversification in the genus Ophrys. Our model species, O. leochroma, is pollinated by Eucera kullenbergi males and lies in the phylogeny between the wasp and Andrena-pollinated species; therefore, it is a remarkable point to understand pollinator shifts. We collected surface extracts of attractive E. kullenbergi females and labellum extracts of O. leochroma and analyzed them by using gas chromatography with electroantennographic detection (GC-EAD) and gas chromatography coupled with mass spectrometry (GC-MS). We also performed field bioassays. Our results show that O. leochroma mimics the sex pheromone of its pollinator’s female by using aldehydes, alcohols, fatty acids, and non-polar compounds (hydrocarbons). Therefore, in terms of the chemistry of pollinator attraction, Eucera-pollinated Ophrys species might represent an intermediate stage between wasp- and Andrena-pollinated orchid species.     

Evaluation of Host-Derived Volatiles for Trapping <Emphasis Type="Italic">Culicoides</Emphasis> Biting Midges (Diptera: Ceratopogonidae)

Culicoides biting midges (Diptera: Ceratopognidae) cause pain and distress through blood feeding, and transmit viruses that threaten both animal and human health worldwide. There are few effective tools for monitoring and control of biting midges, with semiochemical-based strategies offering the advantage of targeting host-seeking populations. In previous studies, we identified the host preference of multiple Culicoides species, including Culicoides impunctatus, as well as cattle-derived compounds that modulate the behavioral responses of C. nubeculosus under laboratory conditions. Here, we test the efficacy of these compounds, when released at different rates, in attracting C. impunctatus under field conditions in Southern Sweden. Traps releasing 1-octen-3-ol, decanal, phenol, 4-methylphenol or 3-propylphenol, when combined with carbon dioxide (CO₂), captured significantly higher numbers of C. impunctatus compared to control traps baited with CO₂ alone, with low release rates (0.1 mg h^?1, 1 mg h^?1) being generally more attractive. In contrast, traps releasing octanal or (E)-2-nonenal at 1 mg h^?1 and 10 mg h^?1 collected significantly lower numbers of C. impunctatus than control traps baited with CO₂ only. Nonanal and 2-ethylhexanol did not affect the attraction of C. impunctatus when compared to CO₂ alone at any of the release rates tested. The potential use of these semiochemicals as attractants and repellents for biting midge control is discussed.     

(1<Emphasis Type="Italic">S</Emphasis>,3<Emphasis Type="Italic">R</Emphasis>)-<Emphasis Type="Italic">cis</Emphasis>-Chrysanthemyl Tiglate: Sex Pheromone of the Striped Mealybug, <Emphasis Type="Italic">Ferrisia virgata</Emphasis>

Derivatives of 2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropanecarboxylic acid (chrysanthemic acid) are classic natural pyrethroids discovered in pyrethrum plants and show insecticidal activity. Chrysanthemic acid, with two asymmetric carbons, has four possible stereoisomers, and most natural pyrethroids have the (1R,3R)-trans configuration. Interestingly, chrysanthemic acid–related structures are also found in insect sex pheromones; carboxylic esters of (1R,3R)-trans-(2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropyl)methanol (chrysanthemyl alcohol) have been reported from two mealybug species. In the present study, another ester of chrysanthemyl alcohol was discovered from the striped mealybug, Ferrisia virgata (Cockerell), as its pheromone. By means of gas chromatography–mass spectrometry, nuclear magnetic resonance spectrometry, and high-performance liquid chromatography analyses using a chiral stationary phase column and authentic standards, the pheromone was identified as (1S,3R)-(?)-cis-chrysanthemyl tiglate. The (1S,3R)-enantiomer strongly attracted adult males in a greenhouse trapping bioassay, whereas the other enantiomers showed only weak activity. The cis configuration of the chrysanthemic acid–related structure appears to be relatively scarce in nature, and this is the first example reported from arthropods.     

Fatal Attraction: <Emphasis Type="Italic">Ricinus communis</Emphasis> Provides an Attractive but Risky Mating Site for <Emphasis Type="Italic">Holotrichia parallela</Emphasis> Beetles

The castor bean, Ricinus communis L., is a non-host plant for the large black chafer, Holotrichia parallela Motschulsky (Coleoptera: Scarabaeidae). In laboratory bioassays we found that this plant was no less attractive than the main host plant (peanut, Arachis hypogaea) and three food plant species: velvetleaf (Abutilon theophrasti), the glossy privet (Ligustrum lucidum), and the Siberian elm (Ulmus pumila). In field trapping experiments a Soxhlet extract of castor bean leaves caught more beetles than the optimal sex lure blend [(R)-(?)-linalool and (L)-isoleucine methyl ester blended in a ratio of 1:4], compared at equal doses (500 μl), and laboratory bioassays indicated that a castor bean plant could enhance the attractiveness of different blend ratios of sex lures. Olfactometer bioassays showed that males prefer volatiles emitted from different combinations of castor bean plant extracts and a signaling female over a female alone. In the presence of castor bean plants copulation rates of H. parallela were highest among all test environments both in laboratory bioassays (60%) and in field tests (70%). This study, combined with our previous observation of the feeding behavior of H. parallela adults on castor bean leaves, suggests that castor bean plants may provide an attractive but risky mating site for H. parallela beetles. The enhancement of male mate-location and copulation rate in the presence of castor bean plants can balance its paralytic effects on H. parallela after intake of potential toxins contained in its leaves.     

<Emphasis Type="Italic">trans</Emphasis>-10,<Emphasis Type="Italic">cis</Emphasis>-12 Conjugated Linoleic Acid Enhances Endurance Capacity by Increasing Fatty Acid Oxidation and Reducing Glycogen Utilization in Mice

The supplementation of conjugated linoleic acid (CLA) has been shown to improve endurance by enhancing fat oxidation during exercise in rodents and humans. This study was designed to investigate the isomer-specific effects of CLA on endurance capacity and energy metabolism in mice during exercise. Male 129Sv/J mice were divided into three dietary groups and fed treatment diet for 6 weeks; control, 0.5 % cis-9,trans-11 (c9,t11) CLA, or 0.5 % trans-10,cis-12 (t10,c12) CLA. Dietary t10,c12 CLA induced a significant increase in maximum running time and distance until exhaustion with a dramatic reduction of total adipose depots compared to a control group, but there were no significant changes in endurance with the c9,t11 CLA treatment. Serum triacylglycerol and non-esterified fatty acid concentrations were significantly lower in the t10,c12 fed mice after exercise compared to control and the c9,t11 CLA fed-animals. Glycogen contents in livers of the t10,c12 fed-mice were higher than those in control mice, concomitant with reduction of serum l-lactate level. There were no differences in non-exercise physical activity among all treatment groups. In addition, the mRNA expression levels of carnitine palmitoyl transferase 1β, uncoupling protein 2 and peroxisome proliferator-activated receptor δ (PPARδ) in skeletal muscle during exercise were significantly up-regulated by the t10,c12 CLA but not the c9,t11 CLA. These results suggest that the t10,c12 CLA is responsible for improving endurance exercise capacity by promoting fat oxidation with a reduction of the consumption of stored liver glycogen, potentially mediated via PPARδ dependent mechanisms.