Uptake of Neonicotinoid Insecticides by Water-Foraging Honey Bees (Hymenoptera: Apidae) Through Guttation Fluid of Winter Oilseed Rape.

The water-foraging activity of honey bees (Apis mellifera L.) on guttation fluid of seed-coated crops, such as winter oilseed rape (WOR; Brassica napus L.), has not yet been evaluated. We analyzed the uptake of active substances (a.s.) in guttation fluid by evaluating residues of honey-sac contents. In autumn, insecticide residues of up to 130 µg a.s. per liter were released in WOR guttation fluid; this concentration is noticeably lower than levels reported in guttation fluid of seed-coated maize. Until winter dormancy, the concentrations declined to <30 µg a.s. per liter. In spring, residues were linked to prewintered plants and declined steadily until flowering. The maximum release of residues in guttation fluid of seed-coated WOR occurs on the first leaves in autumn when the colonies' water demand decreases. For the first time, proof for the uptake of guttation fluid from seed-coated WOR by honey bees was provided by measuring residues in individual honey-sac contents. In total, 38 out of 204 samples (19%) showed residues of thiamethoxam at concentrations ranging from 0.3 to 0.95 µg per liter while the corresponding concentrations in guttation fluid of WOR varied between 3.6 to 12.9 µg thiamethoxam per liter. The amounts of thiamethoxam we found in the honey sacs of water-foraging honey bees were therefore below the thresholds in nectar and pollen that are considered to have negative effects on honey bees after chronic exposure.

Chemical identification and determination of sulfonamides in n-component solid mixtures within THz-region--solid-state Raman spectroscopic and mass spectrometric study.

The identification and quantitative determination of sulfonamidesin solid-state as n-component mixtures is performed. The limits of detection (LODs), accuracy, precision and repeatability are obtained and discussed, using the Raman spectra within 200-30 cm(-1) region (6.00-0.9 THz). The excitations, corresponding to H-bonding deformations, lattice vibrations, as well as coupling modes are used for determination. The validation of the statistical and mathematical tools for procedure of the spectroscopic patterns is performed. The possibilities of baseline correction methods, smoothing procedures, and non-linear curve fitting method for quantitative analysis within THz-region for complex spectroscopic patterns of n-component mixtures (n=1-5) are discussed. The hybrid HPLC tandem mass spectrometry (MS/MS) and powder XRD are applied as independent physical methods for analysis of the studied systems.

Do lab-derived distribution coefficient values of pesticides match distribution coefficient values determined from column and field-scale experiments? A critical analysis of relevant literature.

In this study, we analyzed sorption parameters for pesticides that were derived from batch and column or batch and field experiments. The batch experiments analyzed in this study were run with the same pesticide and soil as in the column and field experiments. We analyzed the relationship between the pore water velocity of the column and field experiments, solute residence times, and sorption parameters, such as the organic carbon normalized distribution coefficient ( ) and the mass exchange coefficient in kinetic models, as well as the predictability of sorption parameters from basic soil properties. The batch/column analysis included 38 studies with a total of 139 observations. The batch/field analysis included five studies, resulting in a dataset of 24 observations. For the batch/column data, power law relationships between pore water velocity, residence time, and sorption constants were derived. The unexplained variability in these equations was reduced, taking into account the saturation status and the packing status (disturbed-undisturbed) of the soil sample. A new regression equation was derived that allows estimating the values derived from column experiments using organic matter and bulk density with an value of 0.56. Regression analysis of the batch/column data showed that the relationship between batch- and column-derived values depends on the saturation status and packing of the soil column. Analysis of the batch/field data showed that as the batch-derived value becomes larger, field-derived values tend to be lower than the corresponding batch-derived values, and vice versa. The present dataset also showed that the variability in the ratio of batch- to column-derived value increases with increasing pore water velocity, with a maximum value approaching 3.5.

Sequestration of camptothecin, an anticancer alkaloid, by chrysomelid beetles.

Camptothecin (CPT), a monoterpene indole alkaloid, is a potent inhibitor of eukaryotic toposiomerase-I. Several derivatives of CPT are in clinical use against ovarian and lung cancers. CPT has been reported from several plant species belonging to the order Asterids, with the highest concentration in Nothapodytes nimmoniana (family Icacinaceae). In this paper, we report an intriguing observation of chrysomelid beetles (Kanarella unicolor Jacobby) feeding on the leaves of N. nimmoniana without any apparent adverse effect. LC-MS/MS analysis of the beetles indicated that 54.9% of the ingested CPT's was recovered from the wings, followed by lesser amounts in the head and abdomen. LC-HRMS analysis revealed that most of the CPT in the insect body was in the parental form available in the plants without any major metabolizable products, including sulfated and glucuronilated forms. The mechanism by which the beetles are able to tolerate substantially high levels of CPT in their body tissue is under investigation.

Properties of the Michael's adducts of the substituted 2-amino-5-oxonitriles.

A series of five substituted 2-amino-5-oxonitriles, obtained by the Michael reaction have been designed, synthesised, isolated and spectroscopically and structurally elucidated by means of single crystal X-ray diffraction, linear-polarized infrared (IR-LD) and UV-spectroscopy, (1)H NMR, mass spectrometry and thermal methods. Theoretical quantum chemical calculations were carried out, thus supporting the experimental optical properties and electronic structure of compounds studied.

Synthesis, spectroscopic and structural study of trans- and cis-(±)-3-phenyl-4-(pyrrolidine-1-carbonyl)-isochroman-1-ones.

Synthesis, spectroscopic and structural study of trans- and cis-(±)-3-phenyl-4-(pyrrolidine-1-carbonyl)-isochroman-1-ones is performed in order to obtain the correlation between the crystal structure and spectroscopic properties of both isomers in solid-state. The methods such as single crystal X-ray diffraction, conventional and linear-polarized IR-spectroscopy, UV-spectroscopy, mass spectrometry, ¹H and ¹³C NMR are employed. Quantum chemical ab initio and DFT calculations are performed, to support the experimental data for the electronic structure and optical properties.

Effects of sample properties and mass spectroscopic parameters on electrospray ionization mass spectra of size-fractions from a soil humic acid.

Size-fractions from a soil humic acid were separated by preparative size-exclusion chromatography (SEC), desalted, and concentrated by ultrafiltration and vacuum centrifugation without being subjected to any freeze-drying process. After having assessed the lack of formation of any multiple-charged ions by high-resolution Fourier transform ion cyclotron resonance electrospray ionization (ESI) mass spectrometry (MS), the size-fractions were used by direct infusion to compare the molecular ion distribution by both atmospheric pressure chemical ionization (APCI)- and ESI-MS in negative mode. The weight- (Mw) and number-averaged (Mn) molecular weight obtained by ESI-MS were invariably larger than by APCI-MS for all size-fractions, thereby indicating that ESI is more efficient than APCI to evaluate the molecular mass distribution of humic samples. No substantial difference was observed when concentration and pH of unfreeze-dried humic size-fractions were varied. The negative mode was applied to assess the effect of cone voltage from -20 to -60 V on ESI of the humic size-fractions further separated through an on-line SEC column. The resulting mass spectra and Mw and Mn values suggested that the variation of cone voltage in ESI-MS affects the ionization potential of associated humic molecules more in solution rather than their fragmentation. These findings agree with previous observations which indicated a limitation of ESI in providing consistent mass detection for a complex mixture of heterogeneous humic molecules, especially when they are aggregated by a freeze-drying process.

Noncentrosymmetric crystals with marked nonlinear optical properties.

The crystal structures and optical properties of the novel (1R,2R)-(-)-1,2-diammoniumocyclohexane squarate trihydrate (1) and bis(hydrogen squarate) (2) were elucidated and reported. Physical methods, single crystal X-ray diffraction, UV-vis-NIR, polarized IR spectroscopy of oriented colloids, mass spectrometry, and thermal methods were used. Quantum chemical DFT calculations were performed with a view to predict the optical and NLO properties of the systems (1) and (2). Both compounds are characterized with the noncentrosymmetric orthorhombic space groups C222(1) (1) and P2(1)2(1)2(1) (2), indicating nonlinear optical properties in the bulk. These organic salts are thermal stable up to 400 degrees C and transparent over the range from 270 to 1100 nm.

Endophytic fungal strains of Fusarium solani, from Apodytes dimidiata E. Mey. ex Arn (Icacinaceae) produce camptothecin, 10-hydroxycamptothecin and 9-methoxycamptothecin.

Camptothecin and 10-hydroxycamptothecin are two important precursors for the synthesis of the clinically useful anticancer drugs, topotecan and irinotecan. In recent years, efforts have been made to identify novel plant and endophytic fungal sources of camptothecin and 10-hydroxycamptothecin. In this study we have isolated endophytic fungi strains from Apodytes dimidiata (Icacinaceae), a medium sized tree from the Western Ghats, India. The fungi were identified as Fusarium solani using both ITS rDNA sequencing and spore morphology. Two strains, MTCC 9667 and MTCC 9668 were isolated, both of which produced camptothecin and 9-methoxycamptothecin in their mycelia; one of the strains, MTCC 9668 also produced 10-hydroxycamptothecin, though in small amounts. The yields of camptothecin in MTCC 9667 and MTCC 9668 were 37 and 53 microg/100g, respectively, after 4 days of incubation in broth culture. The yields of 10-hydroxycamptothecin and 9-methoxycamptothecin in MTCC 9668 were 8.2 and 44.9 microg/100g, respectively. Further research in optimizing the culture conditions of these fungal strains might permit their application for the production of camptothecin and 10-hydroxycamptothecin.

New Au (III), Pt (II) and Pd (II) complexes with pentapeptide glycyl-glycyl-(L)-methyonyl-glycyl-glycine and their interaction with calf thymus DNA.

The three new Au (III), Pt (II) and Pd (II) complexes with pentapeptide glycyl-glycyl-(L)-methyonyl-glycyl-glycine have been synthesized, isolated, and spectroscopically and structurally elucidated in solution and in the solid-state. Solid-state linear-dichroic infrared (IR-LD) spectroscopy of oriented colloids in a nematic liquid crystal host, (1)H- and (13)C-NMR, TGA and DSC, UV-VIS spectroscopy, EPR, ESI- and FAB- mass spectrometry and HPLC tandem mass spectrometry (HPLC-MS/MS) have been used. Quantum chemical calculations and molecular modelling were carried out in order to determine the structures and spectroscopic properties of the ligand, the newly synthesised metal complexes and their interactions with calf thymus DNA. The pentapeptide coordinates in a tetradentate manner with the metal ions via an S-atom on the methyonyl-side chain, two N-amide nitrogens, (after a deprotonation of gly(1) and gly(2) residues) and the primary NH(2) nitrogen of N(termini). The MN(3)S chromophores are distorted to near square planar geometry. Their interaction with calf thymus DNA shows the competitive N7 (G) coordination position, where the pentapeptide residues is coordinated with the metal centers in a tridentate manner through the S-atom and both N-amide centers. This interaction leads to a transfer from a distorted square planar geometry (D(4h) symmetry) to a pseudo tetrahedral (T(d) symmetry) of the metal ions with the obtained dihedral angle values of the MN(3)N7(G) chromophors within 114.67 degrees to 110.92 degrees . The isolated Au (III) complex is stable for about 1.5 months, while the stability of the Au (III) complex/DNA adduct is decreased to 33 days.

Synthesis, spectroscopic and structural elucidation of 1-butyl-4-[2-(3,5-dimethoxy-4-hydroxyphenyl)ethenyl)]pyridinium chloride tetrahydrate.

The novel chloride salt of 1-butyl-4-[2-(4-hydroxyphenyl)ethenyl)]pyridine (1), has been synthesized as the tetrahydrate and its structure and properties elucidated in detail spectroscopically, thermally and structurally, using single crystal X-ray diffraction, linear-polarized solid-state IR-spectroscopy, UV-spectroscopy and mass spectrometry. Quantum chemical calculations were performed with a view to supporting and explaining the experimental structural and spectroscopic data. The compound (1) crystallizes in triclinic P1 space group and its unit cell contains two independent 1-butyl-4-[2-(3,5-dimethoxy4-hydroxyphenyl)ethenyl)]pyridinium] cations, differing with respect to the butyl chain torsion angle for which values of 80.0(9) degrees and 173.6(3) degrees are observed. The cations and anions are joined into infinite layers, formed by two different dimers and including solvent molecules. Hydrogen bonds OH...OH(2) (2.814 A), HOH...O(CH(3)) (2.960 A), OH...Cl (2.967 A), HOH...Cl(-) (3.034, 3.188, 3.161 and 3.062 A) and HOH...OH(2) (2.772 A) are observed. For first time in the literature, we are reporting the crystal structure of the dye with the syring-fragment in the molecule. The spectroscopic properties of the novel compound are compared and with those of the corresponding quinoide form (2). Both the forms (1) and (2) are characterized by 21 and 140 nm solvatochromic effects depending of the type of the solvent. The UV-spectroscopic data in solution confirm the formation of classical H-aggregates in polar protic solvent mixture.

Aspergillus fumigatus Fresenius, an endophytic fungus from Juniperus communis L. Horstmann as a novel source of the anticancer pro-drug deoxypodophyllotoxin.

AIMS: Isolation, identification and characterization of an endophytic fungus from Juniperus communis L. Horstmann, as a novel producer of deoxypodophyllotoxin and its in vitro antimicrobial assay. METHODS AND RESULTS: The methodology for the isolation, identification and characterization of a novel endophytic fungus from the twigs of the J. communis L. Horstmann plant, which specifically and consistently produces deoxypodophyllotoxin, was unequivocally established. The fungus was identified as Aspergillus fumigatus Fresenius by molecular, morphological and physiological methods. Deoxypodophyllotoxin was identified and quantified by high-resolution LC-MS, LC-MS(2) and LC-MS(3). The antimicrobial efficacy of the fungal deoxypodophyllotoxin against a panel of pathogenic bacteria was established. CONCLUSIONS: The production of deoxypodophyllotoxin (found in the host) by the cultured endophyte is an enigmatic observation. It demonstrates the transfer of gene(s) for such accumulation by horizontal means from the host plant to its endophytic counterpart. It would be interesting to further study the deoxypodophyllotoxin production and regulation by the cultured endophyte in J. communis and in axenic cultures. SIGNIFICANCE AND IMPACT OF THE STUDY: This endophyte is a potential handle for scientific and commercial exploitation. Although the current accumulation of deoxypodophyllotoxin by the endophyte is not very high, it could be scaled-up to provide adequate production to satisfy new drug development and clinical needs. However, further refined precursor-feeding and mass-balance studies are required to result in the consistent and dependable production.

1,10-Phenanthrolinium hydrogensquarate monohydrate--a non-centrosymmetric structure from two non-chiral agents.

The novel hydrogensquarate salt of 1,10-phenanthroline has been synthesized, isolated and structurally elucidated by single crystal X-ray diffraction. 1,10-Phenanthrolinium hydrogensquarate monohydrate (1) crystallizes in the non-centrosymmetric P2(1) space group. Its hydrogensquarate anions form a stable dimer by means of ((Sq))OHc...O=C((Sq)) hydrogen bonds with lengths of 2.509, 2.526, 2.510, and 2.524A. The solvent water molecule interacts with the anion dimers by means of strong and moderate hydrogen bonds HOHc...O=C((Sq)) with bond lengths of 2.782 and 2.845A, respectively. The 1,10-phenanthrolinium cation participates in NHc...OH(2) interactions with the water molecule (bond lengths of 2.810, 2.758, 2.779 and 2.760A). Surprisingly, compound contains four independent molecules in the unit cell. Optical properties were elucidated by means of linear-polarized solid-state IR-spectroscopy and UV-spectroscopy. In addition TGA, DSC, DTA data, positive and negative ESI mass spectra as well as (1)H- and (13)C NMR spectra are presented. Quantum chemical methods were used to calculate the electronic structure, vibrational data and electronic spectra as well as non-linear optical properties of neutral 1,10-phenanthroline and its protonated cation. Second harmonic generation measurements of the novel compound demonstrate that the compound possesses effective d coefficients of 1.9+/-0.5 pm V(-1), value that is about three times higher that of the low temperature form of potassium dideuterophosphate.

Sequestration of manure-applied sulfadiazine residues in soils.

It is not the total but the (bio)accessible concentration of veterinary medicines that determines their toxicity in the environment. We elucidate the changes in (bio)accessibility of manure-applied sulfadiazine (SDZ) with increasing contact time in soil. Fattening pigs were medicated with 14C-labeled SDZ, and the contaminated manure (fresh and aged) was amended to 2 soil types (Cambisol, Luvisol) and incubated for 218 days at 10 degrees C in the dark. Antibiotic residues of different bioaccessibility were approached by sequential extractions with 0.01 M CaCl2 (CaCl2 fraction), methanol (MeOH fraction), and finally acetonitrile/water (residual fraction, microwave extraction at 150 degrees C). In each fraction, total radioactivity, SDZ, and its major metabolites were quantified. The results showed that both SDZ and,to a lesser extent 4-hydroxysulfadiazine (4-OH-SDZ) were rapidly reformed from N-acetylsulfadiazine (N-ac-SDZ) during the first 2-4 weeks after fresh manure application, i.e., the N-acetylated metabolite does not sequester in soil to a significant extent Yet, the water and methanol extractable SDZ and 4-OH-SDZ also dissipated rapidly (DT50 = 6.0-32 days) for the fresh manure treatment with similar rate constants for both soil types. In the residual fractions, however, the concentrations of both compounds increased with time. We conclude that the residual fraction comprises the sequestered pool of SDZ and its hydroxylated metabolite. There they are entrapped and may persist in soil for several years. Including the residual fraction into fate studies thus yields dissipation half-lives of SDZ which exceed those previously reported for sulfonamides by a factor of about 100.

Hydrogensquarates of 3-nicotinoyl and 3-isonicotinoyl coumarin--crystal structures and spectroscopic elucidation.

Two novel hydrogensquarates of 3-nicotinoyl (1) and 3-isonicotinoyl (2) coumarin have been synthesized and their structures and properties elucidated spectroscopically and structurally, using single crystal X-ray diffraction, linear-polarized solid-state IR-spectroscopy, UV-spectroscopy and negative ESI MS. Quantum chemical calculations were used to obtain the electronic structure, vibrational data and electronic spectra. The IR-spectroscopic elucidation is carried out by a comparison with the characteristics of corresponding neutral 3-nicotinoyl and 3-isonicotinoyl coumarins.

Self-assembly of hydrogensquarates: crystal structures and properties.

The self-assembly of the hydrogensquarates is elucidated by means of linear-polarized infrared (IR-LD) spectroscopy of oriented colloids in nematic host and the so-called reducing-difference procedure for polarized IR-LD spectra interpretation. The scopes and limitation are discussed on five novel derivatives of squaric acid and its anions, that is, 2-chloro-3-aminopyridinium hydrogensquarate (1), bis (1,2,3,4-tetrahydroquinolinium) squarate (2), bis hydrogensquarate dihydrate salt of 4-(aminomethyl)pyridine (3), N-(2-ammoniumethyl)-piperazinium monohydrate hydrogensquarate squarate (4), and 3-nitropyridinium hydrogensquarate monohydrate (5), respectively. The structures of these compounds 1-5 were solved by means of single-crystal X-ray diffraction, and the crystallographic data were used for the experimental elucidation of the corresponding IR spectra of crystals with respect to studying Fermi-resonance (FR), Davydov splitting (DS), and Fermi-Davydov (FD) as well as Evans' hole effects. The various motifs for self-assembly of squaric acid and its anions in the organic crystals are discussed together with their IR-spectroscopic properties.

N-methylcodeinium iodide--crystal structure and spectroscopic elucidation.

The correlation between the structure and the spectroscopic properties of N-methylcodeinium iodide (1) has been studied, using the methods of single crystal X-ray diffraction, IR-LD spectroscopy of oriented samples as a suspension in nematic liquid crystals, UV-vis spectroscopy and 1H and 13C NMR spectroscopy. HPLC tandem mass spectrometry (HPLC ESI MS/MS) and thermal methods were also employed. Quantum chemical calculations have been performed with a view to obtaining the electronic structure and vibrational properties of the title compound. Compound (1) crystallizes in the space group P2(1)2(1)2(1) and its cations and anions are joined by moderate intermolecular OH...I- interaction of length 3.442A. The codeine molecule exhibits the classical T-shape for opiates. A dihedral angle value of 86.4(5) degrees between the A/B/C and D/E planes is obtained. Rings A and B are effectively coplanar with an interplanar angle of 3.6(3) degrees.

Immunomodulatory activity of an extract of the novel fungal endophyte Entrophospora infrequens isolated from Nothapodytes foetida (Wight) Sleumer.

A novel camptothecin-producing endophytic fungus viz., Entrophospora infrequens was isolated from an important Indian medicinal plant Nothapodytes foetida. The present study reports evaluation ofbioactivities of two novel extracts viz., chloroform (CEEI) and methanolic (MEEI) extracts of Entrophospora infrequens with respect to their immunomodulatory potential in vitro and in vivo (in Balb/c mice). The endophyte E. infrequens was found to synthesize camptothecin, which tested positive in CEEI. The immunomodulatory potential of CEEI and MEEI was compared with standard camptothecin (CPT). Doses of the chloroform extract (CEEI) ranging from 12.5-100 mg/kg body weight, significantly (p < 0.05) stimulated the humoral and cell-mediated immune responses in a dose-dependent manner. MEEI on the other hand significantly (p < 0.05) stimulated the delayed type hypersensitivity (DTH) reaction (by nearly 80%), plaque forming cell (PFC) assay (33%), phagocytic response (38%) and haemagglutination antibody (HA) titre [IgM by 79.07% and IgG by 62.05%] at a dose of 12.5 mg/kg body weight. The present study is the first report of the immunomodulatory potential of this neoteric camptothecin-producing endophyte from Nothapodytes foetida.

Spectroscopic, theoretical and structural characterization of hydrogensquarates of L-threonyl-L-serine and L-serine.

Hydrogensquarates of dipeptide L-threonyl-L-serine (H-Thr-Ser-OH) and L: -serine (HSq x Ser) have been synthesized, isolated and spectroscopic characterized by solid-state linear-polarized IR-spectroscopy, 1H- and 13C-NMR, ESI-MS and HPLC with tandem masspectrometry (MS-MS) methods. The structures of the salts and neutral dipeptide have been predicted theoretically by ab initio calculations. In the case of H-Thr-Ser-OH the theoretical data are supported by IR-LD ones. The hydrogensquarates consist in positive charged dipeptide or amino acid moiety and negative hydrogensquarate anion (HSq) stabilizing by strong intermolecular hydrogen bonds. The data about the L-serine hydrogensquarate are compared with known crystallographic data thus indicating a good correlation between the theoretical predicted structures and experimentally obtained by single crystal X-ray diffraction.

Phytochemical analysis of nine Hypericum L. species from Serbia and the F.Y.R. Macedonia.

The methanol extracts of the aerial parts of nine Hypericum species (H. barbatum, H. hirsutum, H. linarioides, H. maculatum, H. olympicum, H. perforatum, H. richeri, H. rumeliacum and H. tetrapterum), collected on different locations in Serbia and the F.Y.R. Macedonia, were obtained by accelerated solvent extraction (ASE) and analyzed for the content of four constituents (hyperoside, quercitrin, hyperforin and hypericin) by LC-MS/ MS. All studied extracts contained the characteristic four constituents, but their contents varied between different species and locations. The content of hypericin in H. barbatum was significantly higher (3.9 times) than that in H. perforatum.