The essential oil (EO) of Thymus capitatus, seven fractions (F1–F7) obtained from silica gel chromatography, and several pure EO components were evaluated with respect to in vitro activities against Echinococcus multilocularis metacestodes and germinal layer (GL) cells. Attempts to evaluate physical damage in metacestodes by phosphoglucose isomerase (PGI) assay failed because EO and F1–F7 interfered with the PGI-activity measurements. A metacestode viability assay based on Alamar Blue, as well as transmission electron microscopy, demonstrated that exposure to EO, F2 and F4 impaired metacestode viability. F2 and F4 exhibited higher toxicity against metacestodes than against mammalian cells, whereas EO was as toxic to mammalian cells as to the parasite. However, none of these fractions exhibited notable activity against isolated E. multilocularis GL cells. Analysis by gas chromatography-mass spectrometry showed that carvacrol was the major component of the EO (82.4%), as well as of the fractions F3 (94.4%), F4 (98.1%) and F5 (90.7%). Other major components of EO were β-caryophyllene, limonene, thymol and eugenol. However, exposure of metacestodes to these components was ineffective. Thus, fractions F2 and F4 of T. capitatus EO contain potent anti-echinococcal compounds, but the activities of these two fractions are most likely based on synergistic effects between several major and minor constituents.

Addition of a surfactant (alkylaryl polyglycol ether) increased the rate and quantity of 14C-bentazon [3-isopropyl-1H-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide] absorbed by leaves of 3-week-old hydroponically grown sunflower (Helianthus annuus L.). Autoradiographs and radioassays of plant parts indicated that the surfactant enhanced acropetal movement of bentazon in sunflower, whereas bentazon applied alone remained in the treated leaves. Basipetal movement of 14C-bentazon was insignificant in sunflower. High-pressure liquid chromatography showed that 3 days after treatment 40% of the absorbed 14C-bentazon was metabolized to a methanol-soluble metabolite. Thinlayer chromatography substantiated the occurrence of a 14C-bentazon metabolite 3 days after treatment.

Detection and degradation of linuron [3-(3,4-dichlorophenyl) -1 - methoxy -1 - methylurea] in organic soils were studied using biological assays and chromatographic techniques. The level of linuron that caused 50% growth reduction of onion (Allium cepa L.) varied among three soils of greatly differing organic matter contents. Linuron and its metabolites were successfully separated with florisil column chromatography using a five-fraction solvent system; however, only linuron and 3 - (3,4 - dichlorophenyl) -1 -methylurea could be extracted from organic soil samples at satisfactory recovery rates. Soil samples from eight grower fields and from field plots were analyzed to determine the residue level of these two compounds. Quantitative assessment of the compounds was made with high pressure liquid chromatography. Results of the biological assay and chromatographic analysis showed that linuron and its phytotoxic metabolite, 3 - (3,4 - dichlorophenyl) -1 - methylurea, were not accumulating in the organic soils of Ontario and that the levels detected were not phytotoxic to onions when grown in pot bioassays.

The translocation and effects of glyphosate [N-(phosphonomethyl)glycine] were determined in greenhouse-grown peach [Prunus persica (L.) Batsch] seedlings obtained from different seed parents. Two lower branches of 10-week-old seedlings of Rutgers Red Leaf, Bailey, Kalamazoo, Siberian C, and Harrow Blood were sprayed with 0.9 to 18 mg of glyphosate per plant. Seedlings of Harrow Blood, Bailey, and Kalamazoo were more susceptible to injury than were those of Siberian C and Rutgers Red Leaf. Glyphosate at 6, 9, and 18 mg produced necrotic areas on the stems of the former seedlings and at the higher rates tree death resulted. The Siberian C and Rutgers Red Leaf seedlings showed only chlorosis and malformation of apical leaves although slight stem injury occurred 1 month after treatment. Measurements of plant weight, height, and stem diameter indicated that seedlings of Harrow Blood, Bailey, and Kalamazoo tolerated only 3 mg of glyphosate without growth reduction. This was one-half and one-third of the amount which seedlings of Siberian C and Rutgers Red Leaf tolerated, respectively. The concentration of glyphosate in the treated lower branches and the main stem of the seedlings was determined by thin-layer chromatography. The concentrations in the bark were generally similar among all seedlings. Differential tolerance, therefore, was not based on differences in overall glyphosate concentration in tissues but on protective or resistance mechanisms present only in seedlings of Siberian C and Rutgers Red Leaf.

14C-chlorsulfuron {2-chloro-N-[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino] carbonyl] benzenesulfonamide} and its metabolites were extracted from flax (Linum sativum L.), field penny cress (stinkweed) (Thlaspi arvense L. # THLAR), and wheat (Triticum aestivum L.) with an average efficiency of 94% using an aqueous extraction procedure. Chlorsulfuron and its metabolites were separated on a reverse-phase preparative chromatography column by eluting with a step gradient of aqueous 0.1% (v/v) formic acid and methanol. Major peaks were eluted at 35 and 45% methanol, and minor peaks at 10, 25, and 100% methanol. The 45% methanol peak represented unmetabolized chlorsulfuron or its hydroxylated derivative and was the only fraction that exhibited biological activity. In wheat and flax, 75 and 62%, respectively, of the extracted activity were eluted by 35% methanol and, in the case of wheat, this fraction was shown to be a glycosylated derivative of chlorsulfuron. Although 14C-chlorsulfuron was metabolized to a lesser extent in field pennycress, our data indicate that over 50% of the absorbed 14C-activity was recovered in forms other than 14C-chlorsulfuron 5 days after treatment. The separation procedure can be used readily to assess the amount of chlorsulfuron detoxification that occurs in plants.

Considering the time delay in different hohlraum wall positions caused by oblique incidence, the spatio-temporal optical field distribution characteristics of a hohlraum wall, especially during the rising edge of a flat-topped pulse, is simulated by a fast Fourier transform method together with chromatography. Results demonstrate that beam propagation along the hohlraum wall is a push-broom process with complex dynamic spatial–temporal evolution. In the first few picoseconds, the optical intensity of the front position increases rapidly, while that of the rear position is relatively weak. The ratio $R$ of the optical intensity during the rising edge is smaller than that of the steady state. $R$ gradually increases and finally tends to the value of the steady state with time. Calculation also shows that, with shorter total width of the rising edge, $R$ of the optical field decreases and the difference compared to the steady state becomes larger. The evolution is more severe with smaller angle of inclination.

Introduction. Carotenoids havebeen described as possessing several important functional propertiesand health benefits. These properties make these compounds idealfor the always increasing functional food industry as well as forpromoting the consumption of the natural products in which theyare contained. Here, we report the first characterisation of thenon-saponified carotenoid composition in fresh peach fruits and commercialpeach juice and jam. Materials and methods. Fully matureyellow-fleshed peach fruits produced in Sicily were purchased ata local market; they were peeled and the pulp was analysed. Commercialpeach juice and commercial peach jam from three different knownmanufacturers were also purchased at the local market. Both thejuice and jam analysed were produced by local manufacturers fromthe same kind of fresh fruit studied in this work. After carotenoid extractionwith organic solvents, the samples were analysed by a direct HPLC-DAD-APCI-MSmethodology. Results and discussion. Three free carotenoids(zeaxanthin, β-cryptoxanthin and β-carotene) and three monoestersof β-cryptoxanthin were identified and detected in all the samplesanalysed. Interestingly, the carotenoid profile remained the same inall the samples, and it was not affected by the peach processingoccurring during the production of the peach juice and jam. Moreover,small differences were observed in the relative contents of the identifiedcomponents among the samples investigated.

Polycyclic aromatic hydrocarbons (PAHs) are robust and abundant molecules in extraterrestrial environments. They are found ubiquitously in the interstellar medium and have been identified in extracts of meteorites collected on Earth. PAHs are important target molecules for planetary exploration missions that investigate the organic inventory of planets, moons and small bodies. This study is part of an interdisciplinary preparation phase to search for organic molecules and life on Mars. We have investigated PAH compounds in desert soils to determine their composition, distribution and stability. Soil samples (Mars analogue soils) were collected at desert areas of Utah in the vicinity of the Mars Desert Research Station (MDRS), in the Arequipa region in Peru and from the Jutland region of Denmark. The aim of this study was to optimize the solid-phase microextraction (SPME) method for fast screening and determination of PAHs in soil samples. This method minimizes sample handling and preserves the chemical integrity of the sample. Complementary liquid extraction was used to obtain information on five- and six-ring PAH compounds. The measured concentrations of PAHs are, in general, very low, ranging from 1 to 60 ng g−1. The texture of soils is mostly sandy loam with few samples being 100 % silt. Collected soils are moderately basic with pH values of 8–9 except for the Salten Skov soil, which is slightly acidic. Although the diverse and variable microbial populations of the samples at the sample sites might have affected the levels and variety of PAHs detected, SPME appears to be a rapid, viable field sampling technique with implications for use on planetary missions.

Introduction. Among the citrus species, C. sinensis has been the most studied given its importance in terms of production and its industrial application in juices. Some of orange juice's organoleptic and functional properties, which make it an attractive product for the consumer, are due to its carotenoid composition. Xanthophylls can be found in either their free form (as the carotenes are found) or in a more stable fatty acid esterified form in the case of mono- and polyhydroxylated xanthophylls. Detection of adulteration of orange juices is of concern to consumers, regulatory agencies and citrus processing industries, and the study of carotenoid ester composition has been proposed to evaluate fruit products' authenticity. In this study, we report on the native (carotenoid esters and free carotenoids) carotenoid profile of orange juices of eight different varieties. Materials and methods. Monovarietal fresh orange juices were obtained from squeezing mid-season oranges (Citrus sinensis varieties: Bionda, Brasiliana, Moro, Ovale, Sanguinello, Tarocco, Valence and Washington) cultivated and supplied by a local producer. After the extraction of the carotenoids from the samples, the analyses were carried out by HPLC-DAD-APCI-MS. Results and discussion. The results showed that, in the juices studied, the xanthophylls were mostly esterified (93% of the total carotenoid mean content). The different varieties investigated showed variations in their carotenoid contents. The total carotenoid contents ranged from 2.42 µg·g–1 in the Washington variety to 15.8 µg·g–1 in the Valencia variety. Among the monoesters, the Valencia variety showed the highest violaxanthin ester amounts (61%), the Brasiliana variety showed the highest β-cryptoxanthin ester content (86.9%) and the Tarocco variety had the highest luteoxanthin ester amount (75.7%). Moreover, in general, in the Brasiliana, Ovale, Sanguinello, Valencia and Washington varieties, the monoester contents were higher than the diesters, whereas in the Bionda, Moro and Tarocco varieties the opposite was determined. To the best of our knowledge, this is the first time that this analytical approach has been applied to characterising, both qualitatively and quantitatively, the whole carotenoid pattern (carotenoid esters and free carotenoids) in orange juices from the Bionda , Brasiliana, Moro, Ovale, Sanguinello, Tarocco, Valence and Washington varieties. This contribution could also be used to establish authenticity markers among orange varieties that could potentially be used to prevent adulteration.

Sterols in the digestive gland-gonad (DGG) complex of Biomphalaria glabrata (Gastropoda) infected with patent larval stages of Echinostoma caproni (Trematoda) versus uninfected control snails were studied by gas-liquid chromatography. The major sterol present in both populations was cholesterol, 59% in the infected snails and 51% in the controls. Infected snails contained the same phytosterols as the controls—desmosterol, campesterol, stigmasterol, and beta-sitosterol–but the percent composition was reduced. The reduction was significant for both campesterol and stigmasterol.

Hydroxyl radical footprinting is a powerful technique often employed in characterization of the tertiary interactions between proteins and nucleic acids. Following the generation of a nucleic acid “ladder” either by chemical or enzymatic reactions, the radiolabeled products are traditionally separated by denaturing gel electrophoresis and further quantified by phosphorimaging techniques. Here we report the use of ion pair reverse phase liquid chromatography to analyze the products of an RNA footprinting reaction using fluorescently labeled RNA molecules. This technique offers several advantages over existing procedures, including rapid analysis, automation, and direct quantification of the cleavage products without the need to employ radiolabeling. To illustrate the resolving power of this technique, we have analyzed the products of base hydrolysis, generated from a fluorescently labeled RNA molecule and have subsequently used this method to define the solvent accessibility of the substrate strand as it docks with the hairpin ribozyme.