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Abstract In the present study, Strachitunt, an Italian PDO cheese (PDO), traditionally produced starting from raw milk without addition of starter culture (SC) was compared for chemical, physical and microbiological characteristics to an experimental cheese (EC), produced from the same raw milk but with the addition of commercial SC. EC resulted in significantly lower in bacterial counts during the whole period considered (115 days of ripening), for Enterobacteriaceae, Coliforms, Enterococci and Staphylococcus aureus. Strachitunt fatty acids profile was not influenced by the cheese and it was dominated by saturated fatty acid. Volatile compounds analysis revealed that PDO and EC presented the typical aroma of blue veined cheese, where ketones as 2-pentanone, 2-heptanone and 2-nonanone were the most abundant compounds. Considering sensorial analysis, significantly higher scores were obtained for EC if compared to PDO. Highlights • Starter cultures resulted in microbial safety and better sensorial scores. • Starter cultures didn't influence cheese fatty acids profile. • Typical aroma of blue veined cheese was not changed by starter cultures. [ABSTRACT FROM AUTHOR]

Abstract A lack of well-established parameters and assessment values currently impairs biomonitoring of n-heptane exposure. Using controlled inhalation experiments, we collected information on urinary n-heptane metabolite concentrations and the time course of metabolite excretion. Relationships between external and internal exposure were analysed to investigate the suitability of selected metabolites to reflect n-heptane uptake. Twenty healthy, non-smoking males (aged 19–38 years, median 25.5) were exposed for 3 h to 167, 333 and 500 ppm n-heptane, each. Spot urine samples of the volunteers, collected before exposure and during the following 24 h, were analysed for heptane-2-one, 3-one, 4-one, 2,5-dione, 1-ol, 2-ol, 3-ol, and 4-ol using headspace solid phase dynamic extraction gas chromatography/mass spectrometry (HS-SPDE-GC/MS). Starting from median pre-exposure concentrations between <0.5 (3-one) and 82.9 μg/L (4-one), exposure increased the concentrations for all parameters except for 4-one. Median post-exposure concentrations ranged up to 840.4 μg/L (2-ol) and decreased with half-lifes <3 h after exposure. Non-parametric correlation analyses (n = 47, p < 0.05) revealed weak to moderate associations of volume related metabolite excretion with external exposure for 2-one, 3-one and 2,5-dione (R = 0.332–0.753). Heptanol excretion was moderately associated with exposure (R ≥ 0.509) only after creatinine adjustment. Lacking association with external exposure impedes the use of 4-one as heptane biomarker, whereas 2-ol and 3-ol turned out to be sensitive indicators of exposure if creatinine correction is applied. By providing fundamental data on a panel of eight potential heptane metabolites, our study can help to promote biological monitoring of n-heptane exposure. [ABSTRACT FROM AUTHOR]

Highlights • The combining of label-free cell phenotypic assay with 2DLC. • D1 activity location and D2 activity tracking obtained three β 2 -AR agonists. • The first time to discover diarylheptanoids with the β 2 -AR agonistic activity. • Providing possible explanation for the anti-asthmatic effect of C. zedoaria. Abstract Traditional Chinese Medicines (TCMs) have been widely used in clinical practice, and provided a rich source for discovering new drug leads. However, efficient identification of active molecules responsible for the therapeutic effects of complex TCMs is still highly challenging. Here, we combined label-free cell phenotypic assay with two dimensional liquid chromatography (2DLC) to identify potential β 2 -adrenoceptor (β 2 -AR) agonists related to anti-asthmatic effect of Curcuma zedoaria Rosc (C.zedoaria), a commonly used TCM. The ethyl acetate extract of C.zedoaria was first fractionated into 26 fractions. Label-free cell phenotypic profiling was then used to locate the active sites. Orthogonal second-dimensional (D2) separation was performed on two fractions displaying agonistic effect at the β 2 -AR, combined with screening of the D2 fractions to track the activity. Finally, this approach led to the isolation of three known diarylheptanoids, among which diarylheptanoid b exhibited the most potent agonistic activity with an EC 50 value of 5.93 μM. This result was further demonstrated through the chemical synthesis of diarylheptanoid b. It is the first time to discover that diarylheptanoids could activate the β 2 -AR, which may be responsible for the anti-asthmatic effect of C.zedoaria observed traditionally and in clinical application. This study also demonstrates the potential of this integrated strategy for identifying active ingredients and determining the basis of therapeutic materials in complex TCMs. [ABSTRACT FROM AUTHOR]

The social hierarchy of blackbuck plays a crucial role in mate selection and establishment of hierarchy in order to maintain successful reproduction. The factors that influence dominancy have not been yet investigated in the Indian male blackbuck. Here, we investigated the interrelationships between behaviours (aggressive and scent marking), chemical profiles of preorbital gland secretion and faecal testosterone levels in male blackbuck with special reference to dominance hierarchy. The frequency of aggressive behaviour, preorbital gland scent marking behaviour and faecal testosterone level were significantly higher (P <0.001) in the dominant males than the other males. Among the 43 major volatile compounds identified in the pre-orbital gland posting of dominant and subordinate male Blackbucks, four compounds viz., 2-methyl propanoic acid (I), 2-methyl-4-heptanone (II), 2,7-dimethyl-1-octanol (III) and 1,15-pentadecanediol (IV) were present only in the preorbital gland post of the dominant male during the hierarchy period. The results suggest that male blackbuck preorbital gland marking behaviour is meant to defend the home range or territorial region, and the scent odour suppresses aggression, scent marking, scent production and territorial patrolling of subordinate males. The behavioural expression, level of testosterone and volatile chemical profiles are closely interlinked towards establishment of dominance in the blackbuck. This investigation is the first of its kind to detect establishment of dominance hierarchy based on identification of volatile chemical compounds of preorbital gland and assessment of faecal testosterone in blackbuck. [ABSTRACT FROM AUTHOR]

A new series of diaryl heptanones ( 12a-q ) were synthesized and their structures were confirmed by its 1 H, 13 C NMR and Mass spectral data. These analogs were evaluated for their anti-oxidant activity and potential to inhibit 5-lipoxygenase. Compounds 12k and 12o showed potent in vitro 5-lipoxygenase enzyme inhibitory activity with IC 50 values of 22.2, 21.5 μM, which are comparable to curcumin (24.4 μM). Further they also have shown significant antioxidant activity. Molecular docking studies clearly showed correlation between binding energy and potency of these compounds. [ABSTRACT FROM AUTHOR]

Measurements of densities, ρ , ρ 123 and speeds of sound, u , u 123 of binary 1,3-dioxolane (1) + 1,4-dioxane (2) and ternary 1,3-dioxolane (1) + N-methylpyrrolidi-2-one or 1,4-dioxane (2) + cyclohexanone or cycloheptanone (3) mixtures have been carried out over the entire range of mole fraction at 293.15, 298.15, 303.15, 308.15 K and atmospheric pressure. The excess molar volumes, V 12 E , V 123 E and excess isentropic compressiblities, ( κ S E ) 12 , ( κ S E ) 123 have been determined from experimental data. The V 123 E and ( κ S E ) 123 data for 1,3-dioxolane (1) + N-methylpyrrolidin-2-one (2) + cyclohexanone or cycloheptanone (3) and 1,3-dioxolane (1) + 1,4-dioxane (2) + cycloheptanone (3) mixture are negative over entire composition of (1) and (2). While V 123 E for 1,3-dioxolane (1) + 1,4-dioxane (2) + cyclohexanone (3) are positive across full range of compositions of (1) and (2); the sign and magnitude of ( κ S E ) 123 values vary with change in composition of the constituent molecules. The V 12 E , V 123 E and ( κ S E ) 12 , ( κ S E ) 123 data have been fitted to Redlich-Kister equation to determine binary, ternary adjustable parameters and standard deviations. The V 123 E and ( κ S E ) 123 data have been analyzed in terms of Graph Theory. It has been observed that Graph theory correctly predicts the sign as well as magnitude of V 123 E and ( κ S E ) 123 data of the studied ternary mixtures. [ABSTRACT FROM AUTHOR]

Abstract A concise asymmetric total synthesis of Amaryllidaceae alkaloid (+)- trans -dihydronarciclasine is accomplished starting from optically pure 7-azabicyclo[2.2.1]heptanone scaffold in 13 linear steps. Key features of the strategy include substrate-directed stereoselective installation of the trans B-C ring junction and regioselective Wacker-type internal olefin oxidation to provide a rapid access to all hydroxyl functionalities over the key cyclohexane ring in a stereocontrolled manner. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

2-Heptanone (methyl n -amyl ketone) is a ketone that produces alarm reactions in insects (e.g., bees and ants). As an olfactory stimulus, 2-heptanone produces anxiety reactions in the short term and despair in the long term in rodent models. Among the anatomical connections of the olfactory system that integrate behavioral responses, connections between the amygdala and nucleus accumbens are important, which in turn form a circuit with the ventral tegmental area (VTA). 2-Heptanone increases the firing rate of amygdala neurons without participation of the vomeronasal organ. The olfactory amygdala-VTA-nucleus accumbens circuit may integrate defensive behaviors, but the possible actions of 2-heptanone on the responsivity of VTA-nucleus accumbens connections have not yet been explored. In the present study, multiunit activity recordings were obtained in adult Wistar rats from the core and shell subregions of the nucleus accumbens during electrical stimulation of the VTA under basal conditions and later during simultaneous stimulation of the VTA and olfactory exposure to 2-heptanone. 2-Heptanone reduced the responsivity of the VTA-nucleus accumbens shell but did not influence the responsivity of the VTA-nucleus accumbens core. The lower VTA-nucleus accumbens shell excitability may be related to a primary defensive warning when exposed to an alarm pheromone. [ABSTRACT FROM AUTHOR]

Pheromones are chemical substances released into the environment by an individual, which trigger stereotyped behaviors and/or physiological processes in individuals of the same species. Yet, a novel hypothesis has suggested that pheromones not only elicit innate responses but also contribute to behavioral plasticity by affecting the subjective evaluation of appetitive or aversive stimuli. To test this hypothesis, we exposed bees to three pheromonal components whose valence was either negative (i.e., associated with aversive events: isopentyl acetate and 2-heptanone) or positive (i.e., associated with appetitive events: geraniol). We then determined the effect of this exposure on the subjective evaluation of aversive stimuli by quantifying responsiveness to a series of increasing electric shock voltages before and after exposure. Two experiments were conducted varying the time-lapse between shock series (15 min in Experiment 1, and 24 h in Experiment 2). In Experiment 1, we observed a general decrease of shock responsiveness caused by fatigue, due to the short lapse of time between the two series of shocks. This decrease could only be counteracted by isopentyl acetate. The enhancing effect of isopentyl acetate on shock responsiveness was also found in Experiment 2. Conversely, geraniol decreased aversive responsiveness in this experiment; 2-heptanone did not affect aversive responsiveness in any experiment. Overall, our results demonstrate that certain pheromones modulate the salience of aversive stimuli according to their valence. In this way, they would affect the motivation to engage in aversive responses, thus acting as modulators of behavioral plasticity. [ABSTRACT FROM AUTHOR]

Excess molar enthalpies $$ H_{{}}^{\text{E}} $$ for binary 1,3-dioxolane (1) + 1,4-dioxane (2) or N-methylpyrrolidin-2-one (2) + cyclohexanone or cycloheptanone (3) and $$ H_{123}^{\text{E}} $$ for ternary 1,3-dioxolane (1) + N-methylpyrrolidin-2-one or 1,4-dioxane (2) + cyclohexanone or cycloheptanone (3) mixtures have been measured over the entire mole fraction range at 308.15 K and atmospheric pressure using a micro differential calorimeter (Model-l DSC 7 Evo). The $$ H_{{}}^{\text{E}} $$ and $$ H_{123}^{\text{E}} $$ data have been correlated with composition by fitting of the corresponding data to the Redlich-Kister equation. The topology of the constituent molecules (Graph theory) has been utilized to predict $$ H_{123}^{\text{E}} $$ values of the present mixtures. It is observed that the $$ H_{123}^{\text{E}} $$ values calculated by Graph theory compare well with their corresponding experimental values. The $$ H_{123}^{\text{E}} $$ data have also been tested in terms of the Prigogine-Flory-Patterson (PFP) theory. [ABSTRACT FROM AUTHOR]

Many bacteria, fungi, and plants produce volatile organic compounds (VOCs) emitted to the environment. Bacterial VOCs play an important role in interactions between microorganisms and in bacterial-plant interactions. Here, we show that such VOCs as ketones 2-heptanone, 2-nonanone, and 2-undecanone inhibit the DnaKJE-ClpB bichaperone dependent refolding of heat-inactivated bacterial luciferases. The inhibitory activity of ketones had highest effect in Escherichia coli ibpB::kan cells lacking small chaperone IbpB. Effect of ketones activity increased in the series: 2-pentanone, 2-undecanone, 2-heptanone, and 2-nonanone. These observations can be explained by the interaction of ketones with hydrophobic segments of heat-inactivated substrates and the competition with the chaperones IbpAB. If the small chaperone IbpB is absent in E. coli cells, the ketones block the hydrophobic segments of the polypeptides and inhibit the action of the bichaperone system. These results are consistent with the data on inhibitory effects of VOCs on survival of bacteria. It can be suggested that the inhibitory activity of the ketones indicated is associated with different ability of these substances to interact with hydrophobic segments in proteins. [ABSTRACT FROM AUTHOR]

Liquid-liquid equilibrium (LLE) for the ternary (3-heptanone + phenol + water) system has been determined under atmospheric pressure at 298.15 K, 303.15 K, 318.15 K and 323.15 K. The NRTL and UNIQUAC models were used to correlate the experimental results. The corresponding binary parameters were obtained and their physical meaning is explained by intermolecular attractive energy. The results from the two models agree well with experimental values. The NRTL model was more accurate than that of the UNIQUAC model. Meanwhile, the NRTL model was used to regress all the experimental values at different temperatures simultaneously, which is defined as total-regression. Compared with the individual regression by the NRTL model, the total regression by the NRTL model has fewer parameters and covers a wider interpolated range from 298.15 K to 323.15 K. The distribution coefficient for phenol changes with temperature. The phenol concentration can be expressed as a function of activity coefficient of phenol in both phases. The effect of temperature on the extraction performance of 3-heptanone was also investigated. The phenol extraction process by 3-heptanone is exothermic. The increase of temperature is not a benefit to phenol extraction. [ABSTRACT FROM AUTHOR]

The nematode Caenorhabditis elegans exhibits behavioral responses to a wide range of odorants associated with food and pathogens. A previous study described a Trojan Horse-like strategy of pathogenesis whereby the bacterium Bacillus nematocida B16 emits the volatile organic compound 2-heptanone to trap C. elegans for successful infection. Here, we further explored the receptor for 2-heptanone as well as the pathway involved in signal transduction in C. elegans. Our experiments showed that 2-heptanone sensing depended on the function of AWC neurons and a GPCR encoded by str-2. Consistent with the above observation, the HEK293 cells expressing STR-2 on their surfaces showed a transient elevation in intracellular Ca2+ levels after 2-heptanone applications. After combining the assays of RNA interference and gene mutants, we also identified theG subunits and their downstream components in the olfactory signal cascade that are necessary for responding to 2-heptanone, including Gα subunits of egl-30 and gpa-3, phospholipase C of plc-1and egl-8, and the calcium channel of cmk-1 and cal-1. Our work demonstrates for the first time that an integrated signaling pathway for 2-heptanone response in C. elegans involves recognition by GPCR STR-2, activation byGα subunits of egl-30/gpa-3 and transfer to the PLC pathway, indicating that a potentially novel olfactory pathway exists in AWC neurons. Meanwhile, since 2-heptanone, a metabolite from the pathogenic bacterium B. nematocida B16, can be sensed by C. elegans and thus strongly attract its host, our current work also suggested coevolution between the pathogenic microorganism and the chemosensory system in C. elegans. [ABSTRACT FROM AUTHOR]

Trapping brown rats is challenging because they avoid newly placed traps in their habitat. Herein, we report the identification of the sex pheromone produced by male brown rats and its effect on trap captures of wild female brown rats. Collecting urine- and feces-soiled bedding material of laboratory-kept rats and comparing the soiled-bedding odorants of juvenile and adult males, as well as of adult males and females, we found nine compounds that were specific to, or most prevalent in, the odor profiles of sexually mature adult males. When we added a synthetic blend of six of these compounds (2-heptanone, 4-heptanone, 3-ethyl-2-heptanone, 2-octanone, 2-nonanone, 4-nonanone) to one of two paired food-baited trap boxes, these boxes attracted significantly more laboratory-strain female rats in laboratory experiments, and captured ten times more wild female rats in a field experiment than the corresponding control boxes. Our data show that the pheromone facilitates captures of wild female brown rats. [ABSTRACT FROM AUTHOR]

Diarylheptanoids represent a group of plant secondary metabolites that possess multiple biological properties and are increasingly recognized for their therapeutic potential. A comparative study was performed on structurally analogous diarylheptanoids isolated from the bark of green ( Alnus viridis ) and black alder ( Alnus glutinosa ) to address their biological effects and determine structure-activity relationship. The structures and configurations of all compounds were elucidated by NMR, HR-ESI-MS, UV and IR. Diarylheptanoids actions were studied in human non-small cell lung carcinoma cells (NCI-H460) and normal keratinocytes (HaCaT). A. viridis compounds 3v, 5v, 8v and 9v that possess a carbonyl group at C-3 were considerably more potent than compounds without this group. A. viridis / A. glutinosa analogue pairs, 5v / 5g and 9v / 9g , which differ in the presence of 3′ and 3″-OH groups, were evaluated for anticancer activity and selectivity. 5v and 9v that do not possess 3′ and 3″-OH groups showed significantly higher cytotoxicity compared to analogues 5g and 9g . In addition, these two A. viridis compounds induced a more prominent apoptosis in both cell lines and an increase in subG 0 cell cycle phase, compared to their A. glutinosa analogues. 5v and 9v treatment triggered intracellular superoxide anion accumulation and notably decreased mitochondrial transmembrane potential. In HaCaT cells, 9v and 9g with a 4,5 double bond caused a more prominent loss of mitochondrial transmembrane potential compared to 5v and 5g which possess a 5-methoxy group instead. Although green alder diarylheptanoids 5v and 9v displayed higher cytotoxicity, their analogues from black alder 5g and 9g could be more favorable for therapeutic use since they were more active in cancer cells than in normal keratinocytes. These results indicate that minor differences in the chemical structure can greatly influence the effect of diarylheptanoids on apoptosis and redox status and determine their selectivity towards cancer cells. [ABSTRACT FROM AUTHOR]

The lesser (or small) chestnut weevil, Curculio sayi (Gyllenhal), is the key economic pest of chestnut in the central and eastern regions of the United States. Previous research identified the major components of the volatile profile emanating from several chestnut plant tissue types. The goal of this project was to evaluate for the first time the physiological (via electroantennogram) and behavioral (via Y-tube olfactometer) responsiveness of C. sayi to blends of selected key chestnut volatile organic compounds (VOCs) across weevil sex and seasonal period of adult activity. The VOC treatment mixtures that generated the highest (and mostly significant) mean electroantennogram (EAG) responses for both sexes and periods of adult activity were the 2-compound mixture treatments, specifically the treatments of 2-heptanone + ethyl butyrate, 2 heptanone + (E)-2-hexenal, and (E)-2-hexenal + ethyl butyrate. All 3- and 4-compound mixtures generated significantly lower mean EAG responses than most of the 2-compound mixture treatments. Results of the behavioral study did not reflect the results from the EAG study. Both male and female weevils, regardless of when they were collected during the season, did not exhibit a significantly greater preference towards any of the VOC mixture treatments compared with a control. As such, further studies must be conducted on additional chestnut VOCs in order to identify the optimal blend (and ratios of), as well as dosage, that will elicit a positive behavioral response before such VOCs can be utilized in a C. sayi monitoring and/or management practice. [ABSTRACT FROM AUTHOR]

1-Bromotricyclo[4.1.0.0]heptane reacted with benzene- and methanesulfonyl thiocyanates in benzene at 20°C via anti addition to the central C-C bicyclobutane bond with formation of 6- endo-bromo-6- exo-thiocyanato-7- syn-(R-sulfonyl)bicyclo[3.1.1]heptanes. Treatment of the benzenesulfonyl thiocyanate adduct with potassium tert-butoxide in THF at 20°C gave 7- endo-(benzenesulfonyl)norpinan-6-one, whereas the reaction with 1,8-diazabicyclo[5.4.0]undec-7-ene in methylene chloride afforded 7- exo-(benzenesulfonyl)-norpinane-6-thione which was converted into 7-exo-(benzenesulfonyl)norpinan-6-one by alkaline hydrolysis. [ABSTRACT FROM AUTHOR]

The effects of salts and pH on a mixture of homologous ketone flavours (2-hexanone, 2-heptanone and 2-octanone) binding to salt-extracted pea protein isolates (PPIs) were studied using GC/MS in an aqueous model system. Ionic strength, the specific flavour compound and pH were found to significantly affect protein-flavour binding. Comparing the univalent (NaCl) and divalent (CaCl 2 ) cations, higher concentrations of NaCl (0.25-1 M) greatly promoted protein-flavour binding compared to CaCl 2 , while lower concentrations (0.05-0.1 M NaCl and 0.25 M CaCl 2 ) decreased flavour retention. Considering the effect of anions (0.5 M), flavour binding by PPIs was dependent upon the position of the anions in the lyotropic series such that binding decreased in the order: Na 2 SO 4 >> NaCl > NaCH 3 COO = no salt > NaSCN. In terms of the effect of pH, overall flavour binding followed the order: pH 5 > pH 7 > pH 9 > pH 11 > pH 3. Competitive binding between the selected flavour mixture and PPIs was also observed as evidenced by 2-octanone more effectively binding to PPIs than 2-heptanone and 2-hexanone. This research supported existing knowledge on the effects of salts and pH on flavour partitioning with and without protein present. This further promotes utilization of plant proteins in aqueous food systems to achieve desired flavour attributes. [ABSTRACT FROM AUTHOR]

Quaternary centers are rapidly and selectively installed in a series of seven-membered and bridged cyclic oxonitriles through conjugate addition of an alkoxide to chloroalkenenitriles, followed by a Claisen rearrangement. Using this strategy, the stereogenic information of the carbinol in secondary allylic alcohols is transferred to the newly generated quaternary center. Experimentally, the sequence rapidly gives alkyl cyanocycloheptanones and bicycloalkanonecarbonitriles in good yield and with high selectivity, in a single synthetic operation. [ABSTRACT FROM AUTHOR]

The Baeyer–Villiger oxidation of cyclic ketones (I) to the corresponding lactones (II) can be improved using m -CPBA under microwave dielectric heating. A dramatic reduction of time—3 min compared to 5 days at room temperature—was observed to transform cycloheptanone into oxocan-2-one. Ω-Hydroxyalkyl hydroxamic acids (III), key intermediates for a rapid access to potent histone deacetylase inhibitors, are obtained in one-pot reaction of lactones using the Weinreb amidation. [ABSTRACT FROM AUTHOR]

Cholesterol oxidation in food and model systems is usually monitored by evaluating cholesterol oxidation products, but the analysis is time-consuming and expensive. Therefore, the determination of volatile compounds deriving from cholesterol thermoxidation could be valuable to identify other possible oxidation markers. Cholesterol alone and in the presence of a triacylglycerol mixture (tripalmitin, tristearin, and triolein) were thermoxidized at 170 °C for 15 min. In both model systems, the total volatile compounds increased three times when oxidation time rose from 5 to 15 min. The main classes of volatile compounds were aldehydes, ketones, alcohols and hydrocarbons, displaying a similar behavior in both systems. After 5 min of oxidation, 2-methyl-6-heptanone was the main volatile compound, followed by 3-methylpentane, 2,3-dimethyl-1-pentene and 3-methylbutanal. To verify if 2-methyl-6-heptanone could be used as volatile marker of cholesterol oxidation, data were compared with the total cholesterol oxidation products content of each system. A significant correlation between total cholesterol oxidation products content and 2-methyl-6-heptanone amount was found when cholesterol was oxidized alone ( r 2 = 0.994) and in presence of triacylglycerols ( r 2 = 0.998). When egg yolk was thermoxidized at 80 °C for 6 h, 3-methylbutanal was the volatile compound that better explained the oxidative trend in this food system, showing a significant correlation with cholesterol oxidation rate ( r = 0.91). In conclusion, 2-methyl-6-heptanone and 3-methylbutanal could represent an easy and cheaper strategy for monitoring cholesterol oxidation in model systems and food samples, respectively; however, a deeper investigation on the amount and type of volatile compounds generated from cholesterol oxidation according to the food matrix, should be carried out. [ABSTRACT FROM AUTHOR]

C 2 -symmetric ester-amide functionalized azolium salt was synthesized from readily available α-amino ester such as L -serine methyl ester. The combination of a Cu salt and the chiral azolium salt promoted the asymmetric conjugate addition reaction of enones with dialkylzincs. Thus, treatment of acyclic enone such as chalcone with Et 2 Zn afforded the corresponding 1,4-adduct with up to 85% ee. An excellent ee value of 93% was obtained when 3-nonen-2-one was reacted with Et 2 Zn. The present catalytic system was found to be useful for the 1,4-addition reaction of cyclic enone. For example, the reaction of 2-cyclohepten-1-one with Et 2 Zn produced ( R )-3-ethylcycloheptanone with 80% ee. [ABSTRACT FROM AUTHOR]

Highlights: [•] H E for binary systems of cycloalkanones with n-nonane have been measured. [•] Experimental data were well represented by the Redlich–Kister equation. [•] The experimental results have been used to test the applicability of the Wilson, NRTL and UNIQUAC models. [Copyright &y& Elsevier]

A sequential Diels-Alder reaction/rearrangement sequence was developed for the synthesis of diverse functionalized bicyclo[2.2.1]heptanes as novel floral and woody odorants. The outcome of the rearrangement depended on the substitution pattern of the dienes. 2D NMR analysis has established the correct relative configuration of the bicyclo[2.2.1]heptanone, which was originally misassigned. Furthermore, when the initiating DA reaction was catalyzed by a chiral Lewis acid, the bicyclo[2.2.1]heptane derivatives including (+)-herbanone can be obtained in an enantiomeric ratio (er) up to 96.5:3.5. [ABSTRACT FROM AUTHOR]

Abstract: Densities, ρ, speeds of sound, u and excess heat capacities, C P E (293.15, 298.15, 303.15, 308.15K) and excess molar enthalpies, HE (298.15K) for the binary acetone (i)+cyclopentanone or cyclohexanone or cycloheptanone (j) mixtures have been measured as a function of composition at atmospheric pressure. The measured ρ and u data have been employed to determine excess molar volumes, VE and excess isentropic compressibilities, κ S E . The VE , κ S E , HE , and C P E data of the investigated mixtures have been fitted to Redlich–Kister equation to obtain binary parameters and standard deviations. The analysis of thermodynamic data in terms of Graph theory suggests that VE , κ S E , HE , and C P E values predicted by the Graph theory compare well with their experimental values. [Copyright &y& Elsevier]

Two bis-chelates M( tmih) (M = Cu(II), Ni(II), tmih = (CH)C(NCH)CHCOC(CH)) are synthesized and their crystal structures are determined using XRD (Bruker APEX-II diffractometer with a CCD detector, λMo K, λCu K, graphite monochromator, T = 240(2) K and 296(2) K): Cu(tmih) ( I) (space group P2/ c, a = 12.9670(8) Å, b = 18.4921(9) Å, c = 11.0422(6) Å, β = 93.408(4)°, V = 2643.1(3) Å, Z = 4) and Ni(tmih) ( II) (space group P2/ c, a = 12.810(2) Å, b = 18.529(2) Å, c = 11.243(2) Å, β = 91.959(7)°, V = 2667.1(6) Å, Z = 4). The complexes are isostructural; the coordination polyhedron of metal atoms is a flattened tetrahedron formed from two O atoms (Cu-O of 1.901(2) Å, 1.892(2) Å, Ni-O of 1.845(2) Å, 1.833(2) Å) and two N atoms (Cu-N of 1.976(3) Å, 1.972(3) Å, Ni-N of 1.911(2) Å, 1.920(2) Å) of the ligand; the chelate OMN angles (M = Cu(II), Ni(II)) are in the 87.4-93.1° range; the OMO and NMN angles are 162.2° and 167.2° in I, 171.1° and 173.2° in II. The complexes have the molecular structures formed from isolated molecules bonded by van der Waals interactions. Using a quantum chemical hybrid M06 method, the structures of copper(II) chelates with the H, CH, CHCH, CH(CH), and C(CH) substituents at the nitrogen atom are calculated. Found that with a bulky substituent at the nitrogen atom, the formation of chelates is hindered due to the intraligand repulsion between the atoms of this substituent and the tert-butyl group. [ABSTRACT FROM AUTHOR]

This work presents a new formula to calculate the surface tension of ketones. As a first step, an analysis of the available data of the experimental surface tension data for ketones was made. Experimental data were collected for the following pure fluids: acetone, 2-butanone, 2-pentanone, 3-pentanone, 2-hexanone, 3-heptanone, 4-heptanone, 2-octanone, and 6-undecanone. The data were then regressed with the most reliable semi-empirical correlation methods in the literature based on the corresponding states theory. The final equation proposed is very simple and gives noticeable improvement with respect to existing equations. [ABSTRACT FROM AUTHOR]

Abstract: Bio-inspired materials designed for mimicking nature has gained attention in the last years, owing to their appealing properties, such as adhesive and self-cleaning properties. However, studies reporting bio-inspired sensors able to detect minimal amounts of pheromones are still scarce. Here we report on the functionalization of AFM cantilever with polyaniline (PANI), which was used as a sensor to detect pheromone 2-heptanone. This hormone is very significant for honey bees, which release it as a repellent scent marking to avoid enemies and other bees. The functionalization of the sensor was achieved by depositing a thin film of PANI in the emeraldine state on the cantilever through spin-coating. Infrared spectroscopy showed that the 2-heptanone was adsorbed by PANI film deposited on cantilever surface. The linear response of the coated cantilever sensor regarding 2-heptanone concentration for distinct temperatures was evaluated, as well as its mechanical behavior, hysteresis and storage time. The approach proposed here to functionalize AFM cantilever with PANI film to detect 2-heptanone showed a potential methodology for designing sensors able to detect minimal amounts of pheromones and natural compounds. [Copyright &y& Elsevier]

A 1:1 mixture ofP(SiMe3)3and B(p-C6F4H)3reacts with 3equiv of 4-heptanone to afford a 1:2 mixture of [(Me3SiO)(n-Pr)2C]H2P–B(p-C6F4H)3and the silyl enol ether,4-trimethylsiloxy-3-heptene. Subsequent thermolysis of the adductproduces H3P–B(p-C6F4H)3and an additional equiv of silyl enol ether.In the presence of a catalytic quantity of B(p-C6F4H)3, however, P(SiMe3)3reacts with 4-heptanoneto produce a 1:1 mixture of [(Me3SiO)(n-Pr)2C]2PH and silyl enol ether. Heating thismixture further produces [(Me3SiO)(n-Pr)2C]PH2, which is eventually converted to elementalphosphorus. [ABSTRACT FROM AUTHOR]

Background Controlled-release formulations of bioactive agents are of increasing interest for effective pest control. Volatile 2-heptanone is a bioactive agent that has shown potential as a pesticide. The aim of this study was to investigate the kinetics of release of 2-heptanone incorporated into lipid films or composite solid lipid particle ( SLP) films. Results Effective 2-heptanone diffusivity was estimated to be between 0.1 and 2.5 mm2 day−1 during the first week and between 0.05 and 0.1 mm2 day−1 during the next 5 weeks. The films that showed better retention of 2-heptanone were the paraffin lipid films. Inclusion of SLPs into paraffin films increased the release rate of 2-heptanone, mainly owing to a decrease in the film firmness as the composite SLP film became less crystalline and more brittle. In contrast, SLPs decreased the kinetics of 2-heptanone release in Acetem films owing to an increase in the film firmness. Conclusions The results indicated that the use of SLPs as a method for controlled release can improve the delivery of the natural pesticide 2-heptanone if the SLPs have good compatibility with the matrix, leading to an increase in firmness of the films without increasing their porosity. Published 2012. This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

The extraction equilibrium behaviorof Li by tributyl phosphate (TBP), diisobutyl ketone, acetophenone,methyl isobutyl ketone, and 2-heptanone in kerosene were investigated.The partition coefficient of Li with TBP in kerosene decreased significantlywhen the volume concentration of TBP was greater than 60%. The valuesderived for the partition coefficients of four selected ketones inkerosene were smaller than that of TBP in kerosene. The stoichiometriccoefficients between TBP and Li, the stoichiometric coefficients betweenthe four selected ketones and Li, and the apparent equilibrium constantfor the extraction reaction equation for TBP and the four ketonesin kerosene were obtained. The tendency in extraction with the TBPand four selected ketones in kerosene can be predicted from theseparameters. The polar solvents used as diluents for TBP can yieldhigher Li partition coefficients, strong dilution effects for TBP,and strong polarity and low density of the extracting solvents formedwith both polar solvents and TBP. [ABSTRACT FROM AUTHOR]

A method for the synthesis of 1-methylcarbapentofuranose derivatives was developed, where 1,2-cis- and 1,2-trans-4-hydroxymethyl-1-methylcyclopentanediols were obtained from intramolecular opening of a 4-epoxy-4-methyl-γ-lactone. An intramolecular aldol reaction of 4-methyl-4-(2-oxoethyl)-γ-lactone derivatives yielded 1,3-cis- and 1,3-trans-4-hydroxymethyl-1-methylcyclopentanediols. [ABSTRACT FROM AUTHOR]

Two novel polypyrrole (PPy) composite solid-phase microextraction (SPME) fiber coatings involving polypyrrole β-naphthalenesulfonic acid (PPy/β-NSA) and polypyrrole graphene (PPy/GR) composite SPME fiber coatings were prepared by a simple sol–gel technique for selectively sampling relatively polar biological volatile organic compounds (VOCs). Crucial preparation conditions of the PPy composite SPME fiber coatings were optimized and are discussed in detail. Physical tests suggested that the PPy composite SPME fiber coatings possessed a porous surface morphology, stable chemical and thermal properties. Due to the inducing polar functional groups in the PPy molecule, the PPy composite SPME fiber coatings achieved a higher extraction capacity and special selectivity for the polar biological VOCs with conjugate structures, compared with commercial SPME fiber coatings. Enrichment factors of most of the VOCs by the PPy/β-NSA and PPy/GR SPME fibers were much higher than those achieved by common commercially available SPME fiber coatings. Finally, the PPy/β-NSA and PPy/GR SPME fiber coatings were applied for the trace analysis of typical polar VOCs from ant and coriander samples coupled with gas chromatography/mass spectrometry (GC/MS) detection, respectively. It was satisfactory that the average contents of 4-heptanone, 4-heptanol, 4-nonanone and methyl 5-methylsalicylate from ant samples were actually found to be 28.0, 58.7, 3.0 and 0.6 μg g−1, and the average contents of nonane, decanal, undecanal and dodecanal from coriander samples were actually found to be 0.79, 0.13, 0.06 and 0.21 μg g−1. The results suggested that PPy composite SPME coatings will be a potentially excellent sampling technique for the trace analysis of polar biological VOCs. [ABSTRACT FROM AUTHOR]

The effect of the presence of an exo- and/or an endo double bond on the geometry of seven membered rings has been investigated by a conformational analysis of methylenecycloheptane, cycloheptamine, borepane, and 4-, 3- and 2-cyclohepten-1-one by the B3LYP/6-311+G(d,p) and CCSD(T)/6-311+G(d,p) levels of theory. The results indicate that both methylenecycloheptane and cycloheptamine have low energy barriers with respect to pseudorotation and a broad potential well centred on the most symmetrical twist-chair conformation. Borepane shows similar characteristics, but with drastically different relative energy values. The introduction of an extra endo double bond in the conformationally flexible cycloheptanone, fixes the family of chair conformations to a single rigid form, but lowers the relative energy of the boat conformations to compete in stability with the former. [ABSTRACT FROM AUTHOR]

Three products arising from LIX® 63 hydroxyoxime degradation have previously been identified, namely 5,8-diethyl-6,7-dodecanedione (diketone), 5,8-diethyldodecan-6-oxime-7-one (keto-oxime) and 5,8-diethyl-7-hydroxy-6-dodecanone (acyloin). In the present work, four additional LIX® 63 degradation products derived from cleavage of the carbon backbone have been detected and identified, namely 2-ethylhexamide, 2-ethylhexanoic acid, 2-ethylhexanal, and 3-heptanone. The amide was isolated and spectroscopically characterized, whereas the other three products were identified primarily using gas chromatography-mass spectrometry. Besides 2-ethylhexanoic acid, the effect of the degradation products on metal selectivity in the synergistic system were assessed and found to have a small detrimental effect on one or more metal ions. [ABSTRACT FROM AUTHOR]

Honeybees secrete 2-heptanone (2-H) from their mandibular glands when they bite. Researchers have identified several possible functions: 2-H could act as an alarm pheromone to recruit guards and soldiers, it could act as a chemical marker, or it could have some other function. The actual role of 2-H in honeybee behaviour remains unresolved. In this study, we show that 2-H acts as an anaesthetic in small arthropods, such as wax moth larva (WML) and Varroa mites, which are paralysed after a honeybee bite. We demonstrated that honeybee mandibles can penetrate the cuticle of WML, introducing less than one nanolitre of 2-H into the WML open circulatory system and causing instantaneous anaesthetization that lasts for a few minutes. The first indication that 2-H acts as a local anaesthetic was that its effect on larval response, inhibition and recovery is very similar to that of lidocaine. We compared the inhibitory effects of 2-H and lidocaine on voltage-gated sodium channels. Although both compounds blocked the hNav1.6 and hNav1.2 channels, lidocaine was slightly more effective, 2.82 times, on hNav.6. In contrast, when the two compounds were tested using an ex vivo preparation--the isolated rat sciatic nerve--the function of the two compounds was so similar that we were able to definitively classify 2-H as a local anaesthetic. Using the same method, we showed that 2-H has the fastest inhibitory effect of all alkyl-ketones tested, including the isomers 3- and 4-heptanone. This suggests that natural selection may have favoured 2-H over other, similar compounds because of the associated fitness advantages it confers. Our results reveal a previously unknown role of 2-H in honeybee defensive behaviour and due to its minor neurotoxicity show potential for developing a new local anaesthetic from a natural product, which could be used in human and veterinary medicine. [ABSTRACT FROM AUTHOR]

Abstract: Off-flavours develop naturally in butter and the process is accelerated by heat. An acoustic wave sensor was used to detect the aroma compounds evolved from heated butter and the results have shown that registered marked changes were coincident to odour changes detected by sensory analysis. The flavour compounds have also been analysed by GC/MS for identification. The response of the sensor was fully characterized in terms of the sensitivity to each of the identified compounds, and sensitivities of the system SPME/sensor were compared with the sensitivities of the system SPME/GC/MS. It was found that the sensor analytical system was more sensitive to methylketones than to fatty acids. The SPME/GC/MS system also showed the highest sensitivity to 2-heptanone, followed by 2-nonanone, but third place was occupied by undecanone and butanoic acid, to which the sensor showed moderate sensitivity. 2-heptanone was found to be an appropriate model compound to follow odour changes till the 500h, and the lower sensitivity of the sensor to butanoic acid showed to be a positive characteristic, as saturation was prevented, and other more subtle changes in the flavour could be perceived. [Copyright &y& Elsevier]

Objective: To evaluate the effect of phototherapy on volatile organic compound (VOC) emissions inside neonatal incubators during standard operational settings. Study design: Air samples were collected from six unoccupied incubators during four standard operational settings and after adding phototherapy. Quantitative analyses were performed using a Tekmar AutoCan Preconcentrator interfaced to an Agilent 6890 Gas Chromatograph with a 5975 Mass Spectrometer. Result: Two VOCs, 2-heptanone and n-butyl acetate, were identified as elevated and mean concentrations increased further with temperature and addition of humidity (4.3 ± 0.93 to 39.66 ± 7.66 ppb [p = 0.001] and 0.68 ± 0.27 to 7.23 ± 1.05 ppb [p ≤ 0.001]; respectively). However, phototherapy did not significantly alter VOC concentrations inside the incubator. Conclusion: The use of phototherapy did not appear to influence 2-heptanone and n-butyl acetate concentrations or generate any new emissions within the neonatal incubator. This study confirmed the effect of temperature and humidity on 2-heptanone and n-butyl acetate, using authentic analytical standards. [ABSTRACT FROM AUTHOR]

Wistar rats subjected to physical stress release a urine alarm pheromone (2-heptanone) that produces signs of anxiety and despair in receptor rats not subjected to physical stress. However, unknown are the effects of 2-heptanone on the firing rate of the basal amygdala, a structure that participates in the expression of fear, and the participation of anterior olfactory epithelial organs, namely the septal organ and vomeronasal organ (SO-VNO). We explored the effects of 2-heptanone applied near the nostrils on single-unit extracellular recordings from the basal amygdala in a sham-operated group and rats that underwent removal of the SO-VNO. The firing rate of basal amygdala neurons in the SO-VNO removal group was significantly higher than in the sham-operated group. In both groups, recordings were classified according to the responses to 2-heptanone (i.e., increased firing rate, decreased firing rate, and no response). SO-VNO removal was associated with an increased firing rate in the three types of neurons. A similar number of neurons increased their firing rate during and after 2-heptanone stimulation in both groups, but such an increase in firing rate was longer in the group of rats subjected to SO-VNO removal. The results indicate that the SO-VNO is not essential for the effect of 2-heptanone on the firing rate of basal amygdala neurons. SO-VNO ablation did not block but rather accentuated the response of amygdala neurons to 2-heptanone. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract: Surface enhanced Raman spectroscopy combined with transposed Orthogonal Partial Least Squares (T-OPLS) was shown to produce chemical images of the natural antibacterial surface-active compound 1,1,3,3-tetrabromo-2-heptanone (TBH) on Bonnemaisonia hamifera. The use of gold colloids functionalised with the internal standard 4-mercapto-benzonitrile (MBN) made it possible to create images of the relative concentration of TBH over the surfaces. A gradient of TBH could be mapped over and in the close vicinity of the B. hamifera algal vesicles at the attomol/pixel level. T-OPLS produced a measure of the spectral correlation for each pixel of the hyperspectral images whilst not including spectral variation that was linearly independent of the target spectrum. In this paper we show the possibility to retrieve specific spectral information with a low magnitude in a complex matrix. [Copyright &y& Elsevier]

2-Halocycloheptanones (Halo = F, Cl, Br and I) were synthesized and their conformational analysis was performed through infrared spectroscopy data. The corresponding conformers geometries and energies were obtained by theoretical calculations at B3LYP/aug-cc-pVDZ level of theory in the isolated state and in solution. It was observed, by both approaches, that the conformational preferences were very sensitive to the solvent polarity, since its increase led to an increase in the population of the more polar conformer. An analysis of these conformational equilibria showed they suffer also the influence of stereoelectronic effects, like hyperconjugation and steric effects. These results were interpreted using natural bond orbital (NBO) analysis, which indicated that the electronic delocalization to the orbital π*C=O is directly involved in the stability increase of conformers I and II. The relative effect of the period of the halogen can also be noted, with changes in the conformational preferences and in the energies involved in the interactions of NBO. [ABSTRACT FROM AUTHOR]

This study was aimed at identifying sex pheromones of the rat (Rattus norvegicus). We characterized the volatiles and semivolatiles of rat preputial gland and voided urine by using gas chromatography–mass spectrometry (GC–MS) and quantified them by their GC areas (abundances) and percentage of GC areas (relative abundances). Although all the compounds other than 4-heptanone and phenol detected were shared by males and females, the quantities for some of these sex-common compounds exhibited sexual dimorphism and decreased with gonadectomy. Thus, these compounds might be sex pheromones. Among them, squalene from preputial glands and 2-heptanone and 4-ethyl phenol from urine were 3 major compounds. They were richer in males and could be suppressed by castration. Adding any of the 3 compounds (at a concentration higher than its physiological level in male urine) to castrated male urine (CMU) increased the attractiveness of CMU to sex-naive females. Adding the 3 together (at the levels in normal male urine) to CMU significantly increased the attractiveness of CMU to females. However, such combination did not fully restore females' preference for urine from intact males, suggesting that some other trace compounds such as 4-heptanone and phenol might also play some roles in sex attractiveness. Thus, squalene, 2-heptanone, and 4-ethyl phenol were indeed male pheromone molecules in rats. Our study also indicates that E,E-β-farnesene and E-α-farnesene, both richer in females than males, might be putative female pheromones. [ABSTRACT FROM AUTHOR]

There is currently a debate about the role played by temporal patterns in neural activity in olfactory coding. An accurate analysis of this question, however, is only possible if the temporal properties of a stimulus itself are well defined. So far, no technique with sufficient temporal resolution has been available to accomplish this. Using a photoionization detector (PID), we show that the configuration of the odor delivery apparatus and the airflow settings greatly influence the integrity of a stimulus profile within an odor delivery apparatus. In a situation where pulsatile odor stimuli are applied to a stationary preparation, we tested the effect of 1) axial and off-center location within the airstream, 2) airflow of the odor delivery, 3) exit tube length, 4) exit tube diameter, 5) orientation of the odor delivery device in relation to the exhaust flow, and 6) exhaust tube air speed. This has important implications for the study of time in olfaction; significant planning must be incorporated into the design of the experiment to provide a well-defined odor delivery system. [ABSTRACT FROM AUTHOR]

Social behaviors of most mammals are affected by chemical signals, pheromones, exchanged between conspecifics. Previous experiments have shown that behavioral responses to the same pheromone differ depending on the sex and endocrine status of the respondent. Although the exact mechanism of this dimorphism is not known, one possible contributor may be due to sexually dimorphic receptors or due to differences in central processing within the brain. In order to investigate the differences in response between male and female mice to the same pheromonal stimulus two urinary compounds (2-heptanone and 2,5-dimethylpyrazine) were used to stimulate the production of Inositol (1,4,5)-trisphosphate (IP3) in microvillar membrane preparations of the vomeronasal organ as an indirect measurement of pheromonal stimulation. Incubation of such membranes from prepubertal mice with urine from the same sex or opposite sex, results in an increase in production of IP3. This stimulation is mimicked by GTPγS and blocked by GDPβS. Furthermore we found that 2-heptanone present in both male and female urine was capable of stimulating increased production of IP3 in the female VNO but not the male VNO. Finally, 2,5-dimethylpyrazine present only in female urine was also only capable of stimulating increased production of IP3 in the female VNO. [ABSTRACT FROM AUTHOR]

A protocol for analysing three-dimensional metacarpophalangeal (MCP) joint motion in vivo using two markers on the proximal phalanx is described. The analysis uses an assumption that the rotation of the phalanx about its own long axis is zero. In an experimental study 24 volunteers had surface markers applied to the dorsal surfaces of their hands and index and long finger proximal phalanges, with three-dimensional marker positions recorded in two hand and finger postures in an incomplete box design using a test-retest protocol. Kinematic parameters from the optoelectronic system were compared with those obtained from three-dimensional reconstruction of bone landmarks and of the marker positions identified on stereoradiographs. Pronation/supination angles obtained from bone landmarks showed high test-retest variability, reflecting the difficulty in obtaining reliable pronation/supination data in small bones without the use of implanted markers. Changes in MCP joint extension and deviation angles determined using two surface markers agree with those obtained from bone landmarks. The results indicate a reproducible protocol for tracking MCP joint motion using only two phalangeal markers, suggesting that the 'no-rotation assumption' can be applied without affecting measures of extension and deviation motion in the normal joint. [ABSTRACT FROM AUTHOR]

Abstract: Two novel norlignans, gymnothedelignans A and B were isolated from the whole plants of Gymnotheca chinensis. These norlignans possess a rare 2/5 epoxy benzocycloheptanone skeleton. Their structures were established on the basis of 1D and 2D NMR spectral data analysis, and the absolute stereochemistry of gymnothedelignans A and B was further confirmed by single crystal X-ray diffraction analysis. [Copyright &y& Elsevier]

Abstract: A metal-free diastereoselective synthesis of novel 4-halo-3,6-di-aryl-2,6-diaza-bicyclo[3.2.0]heptan-7-one by intramolecular endo-trig haloamination of 3-amino-2-azetidinone is reported. The amidiolytic ring opening of diaza-bicyclo[3.2.0]heptan-7-one with sodium methoxide provides an easy access to previously unknown 4-halo-3-aryl amino-pyrrolidine-2-carboxylic acid methyl esters in good yields. [Copyright &y& Elsevier]

Since their discovery in insects, pheromones are considered as ubiquitous and stereotyped chemical messengers acting in intraspecific animal communication. Here we studied the effect of pheromones in a different context as we investigated their capacity to induce persistent modulations of associative learning and memory. We used honey bees, Apis mellifera, and combined olfactory conditioning and pheromone preexposure with disruption of neural activity and two-photon imaging of olfactory brain circuits, to characterize the effect of pheromones on olfactory learning and memory. Geraniol, an attractive pheromone component, and 2-heptanone, an aversive pheromone, improved and impaired, respectively, olfactory learning and memory via a durable modulation of appetitive motivation, which left odor processing unaffected. Consistently, interfering with aminergic circuits mediating appetitive motivation rescued or diminished the cognitive effects induced by pheromone components. We thus show that these chemical messengers act as important modulators of motivational processes and influence thereby animal cognition. David Baracchi et al. show that honey bees exposed to geraniol, a component of an attractant pheromone, exhibit improved olfactory learning and memory while the opposite effect was seen in honey bees exposed to the aversive pheromone, 2- heptanone. These changes occurred through a modulation of appetitive motivation without affecting odor processing, suggesting an important role for pheromones as modulators of motivational and learning processes. [ABSTRACT FROM AUTHOR]

Drift tube ion mobility spectrometers (DT IMS) allow the concentration of different organic compounds to be measured. This gives the opportunity to use these detectors in measuring the penetration of various substances through polymer membranes. Permeation measurements of two substances (2-heptanone and dimethyl methylphosphonate (DMMP)) through a cylindrical silicone rubber membrane were carried out. The membrane separated the aqueous solution from the air. The analyte was introduced into water, and then its concentration in air on the opposite side of the membrane was recorded. Based on the dynamics of detector signal changes, the diffusion coefficients for both tested substances were determined. Determination of permeability coefficients was based on precise quantitative measurements, which took into account the non-linearity of the detector characteristics and the effect of water on detection sensitivity. The analysis of measurement results was based on a mathematical description of diffusion process. [ABSTRACT FROM AUTHOR]

Abstract: In muroid rodents, urine-borne volatile compounds and major urinary proteins (MUPs) constitute the key male pheromones that shape the sexual attractiveness of males. Here, we aimed to examine whether male pheromone levels were related to sexual attractiveness and reproductive success in the North China subspecies of the brown rat (Rattus norvegicus humiliatus). According to the abundance of 2-heptanone (2H), the predominant male pheromone in male urine, male rats were first categorized into a high-2H group and a low-2H group. The levels of the whole volatile profile and non-volatile MUPs were found to be higher in the high-2H group than in the low-2H group. Moreover, the abundances of urinary volatile pheromones or pheromone candidates were positively correlated with the abundance of total MUPs. Two-way choice tests revealed that male urine from the high-2H group was more attractive to females than that from the low-2H group. Microsatellite loci analysis of paternal lineage revealed that the females had single-paternity offspring and that the high-2H group sired more offspring and had higher rates of paternity than did the low-2H group. These results suggest that urine-borne volatile pheromones alone or together with MUP pheromones can predict sexual attractiveness and reproductive success in male rats.Significance statement: Sexual attractiveness can be quantified using volatile and MUP pheromones and their candidates in deposited urine. 2-Heptanone (a major pheromone) and other urine-borne volatile pheromones or their candidates and total MUPs showed the same difference patterns in males and predicted male sexual attractiveness. The abundances of volatile pheromones or their candidates and total MUPs were associated with reproductive success and paternity rate in males. [ABSTRACT FROM AUTHOR]