Analytical discrimination of poisonous and nonpoisonous chemotypes of giant fennel (Ferula communis L.) through their biologically active and volatile fractions

Giant fennel (Ferula communis L.) from Sardinia is characterized by two chemotypes with different biological activities. One chemotype is poisonous, due to prenylcoumarins, and responsible for ferulosis, which mainly affects sheep and goats, cattle, and horses; the other chemotype is nonpoisonous and contains daucane esters. The two chemotypes cannot be distinguished botanically. High-performance liquid chromatography-diode array-ultraviolet detection-mass spectrometry (HPLC-DAD-UV-MS) analysis of the composition of the fractions containing the biologically active metabolites and of the volatile fractions, by gas chromatography-mass spectrometry (GC-MS), of both essential oil and headspace sampled by headspace solid-phase microextraction (HS-SPME) are here shown to be effective in discriminating the poisonous and nonpoisonous chemotypes. HS-SPME with CAR/PDMS/DVB in combination with GC-MS has also been found to be a successful, fully automated one-step method for rapid and unequivocal discrimination of the two chemotypes, using aristolene and allohedycaryol as markers of the poisonous and nonpoisonous chemotypes, respectively.     

Chemical composition of volatiles in Sardinian myrtle (Myrtus communis L.) alcoholic extracts and essential oils

The chemical composition of the volatile fraction of myrtle (Myrtus communis L.) alcoholic extracts and essential oils from leaves and berries collected in different places in Sardinia (Italy) was studied. A simple and rapid liquid-liquid extraction method was used to isolate volatile compounds from myrtle alcoholic extracts followed by GC and GC-MS analysis allowing the detection of 24 compounds. The volatile fraction was characterized by the terpenes fraction corresponding to that of the essential oils and by a fatty acid ethyl esters fraction. The variation during extraction of the volatile fraction in alcoholic extracts of berries and leaves was evaluated. Essential oils were obtained by hydrodistillation, and the yields were on average 0.52 +/- 0.03% (v/w dried weight) and 0.02 +/- 0.00% for leaves and berries, respectively. The essential oils were analyzed by GC and GC-MS, and a total of 27 components were detected, accounting for 90.6-98.7% of the total essential oil composition. Strong chemical variability depending on the origin of the samples was observed. The major compounds in the essential oils were alpha-pinene (30.0 and 28.5%), 1,8-cineole (28.8 and 15.3%), and limonene (17.5 and 24.1%) in leaves and berries, respectively, and were characterized by the lack of myrtenyl acetate.     

Structural elucidation of phototransformation products of azimsulfuron in water

The photodegradation of the sulfonylurea herbicide azimsulfuron, N-[[(4,6-dimethoxypyrimidin-2-yl)amino]carbonyl]-1-methyl-4-(2-methyl-2H-tetrazole-5-yl)-1H-pyrazole-5-sulfonamide (AZS), was studied in water at different wavelengths and in the presence of photocatalysts. AZS was rapidly degraded by UV light, affording three photoproducts. The main product, accounting for about 70% of photodegraded herbicide, was identified as 6-amino-5-[(4,6-dimethoxypyrimidin-2-yl)methylamino]-1,5,6,8-tetrahydro-7-oxa-8lambda(6)-tia-1,2,5,6-tetraza-azulen-4-one (ADTA) by single-crystal X-ray diffraction. With simulated sunlight irradiation, the reaction was slower and 2-amino-4,6-dimethoxypyrimidine (DPA) and 1-methyl-4-(2-methyl-2H-tetrazole-5-yl)-1H-pyrazole-5-sulfonamide (MPS), arising from a photohydrolytic cleavage of the sulfonylurea bridge, were the only byproducts observed. The reactions followed first-order kinetics. The addition of dissolved organic matter (DOM) did not modify significantly the AZS photodegradation rate. The presence of Fe2O3 accelerated more than twice the reaction rate affording two major products, DPA and MPS, together with minor amounts of N-[[(5-hydroxy-4,6-dimethoxypyrimidin-2-yl)amino]carbonyl]-1-methyl-4-(2-methyl-2H-tetrazole-5-yl)-1H-pyrazole-5-sulfonamide (AZS-OH). The greatest degradation rate was detected in the presence of TiO2. Only the photohydroxylation product AZS-OH was observed, which was transformed rapidly into oxalic acid.     

Comparison of the volatile constituents in cold-pressed bergamot oil and a volatile oil isolated by vacuum distillation

The vacuum distillation of bergamot peels furnishes a high-quality essential oil that is totally bergapten-free. This oil was compared with that produced by distillation of cold-pressed oils and those commercially available. The oil obtained by vacuum distillation of the bergamot vegetable matrix shows a composition quite similar to that of the cold-pressed oil. It also displays qualitative characteristics that are superior with respect to those normally observed for essential oils isolated by distillation of cold-pressed oils. Oils isolated by the method presented here can constitute ideal candidates in producing foods, for example, Earl Grey tea, and cosmetic preparations.     

Synthetic pyrazole derivatives as growth inhibitors of some phytopathogenic fungi

The present study was carried out to investigate the antifungal activity of pyrazole/isoxazole-3-carboxamido-4-carboxylic acids, 4-oxo-5-substituted pyrazolo[3,4-d]pyrimidine-6-thiones, and N-alkyl/aryl-N'-(4-carbethoxy-3-pyrazolyl)thioureas against Pythium ultimum, Botrytis cinerea, and Magnaporthe grisea. The results on growth inhibition showed differences in the sensitivity of the three fungi to the tested substances, and in general P. ultimum was shown to be the most sensitive. On all phytopathogens the best results within the pyrazole/isoxazolecarboxamide series are given by the compounds with the carboxamide and carboxylic groups in positions 3 and 4; the presence of these groups seems to be critical for biological activity in this series of compounds. Among the pyrazolopyrimidines the derivative supplied with the benzylic group was the most active on the three fungi and in particular against P. ultimum. Several compounds belonging to the thiourea series are able to inhibit selectively M. grisea at 50 and 10 microg mL(-1), doses at which the reference commercial compound tricyclazole had low or no effect.     

Differential cell counts in canine cytocentrifuged bronchoalveolar lavage fluid: a study on reliable enumeration of each cell type

Background: Bronchoalveolar lavage (BAL) allows cell recovery from the lower respiratory tract; differential cell counts of BAL fluid gives important information in the assessment of various bronchial and pulmonary diseases. To the best of our knowledge no study has investigated the relation between the number of cells counted and the reproducibility of BAL fluid differential cell counts. Objective: The purpose of this study was to investigate using statistical methods how many cells should be counted in cytocentrifuged BAL fluid preparations in order to obtain a reliable enumeration of each cell type. Methods: BAL fluid samples from dogs with suspected bronchopulmonary disease were obtained during fiberoptic bronchoscopy with a standardized protocol. Differential cell counts were performed on May–Grünwald–Giemsa‐stained cytocentrifuged preparations by 2 independent observers. Reproducibility for the enumeration of each cell type was expressed as the intraclass correlation coefficient. We considered a threshold level of ≥0.90 to be high and a threshold level of ≥0.85 to be adequate. Results: Forty BAL fluid samples were included in the study. For neutrophils, alveolar macrophages, and eosinophils high reproducibility was reached by counting 200 cells; adequate reproducibility was reached for lymphocytes and bronchial epithelial cells by counting 500 cells. Conclusions: A 500‐cell differential count is required for all types of cells to be quantified with adequate reproducibility in canine cytocentrifuged BAL fluid samples.     

Effect of variety choice, resistant rootstocks and chitin soil amendments on soil-borne diseases in soil-based, protected tomato production systems

Soil-borne diseases are the most significant crop protection problem in soil-based, low-input and especially organic glasshouse production systems in Europe. While chemical soil disinfestation has been the control method of choice in conventional farming systems, soil steaming has been the main strategy for the control of soil-borne diseases in organic production. Both methods are extremely expensive and have been increasingly restricted for environmental reasons by governments, and integrated and organic farming standard-setting bodies. The use of disease-tolerant varieties, grafting onto resistant rootstocks and chitin soil amendments were evaluated as potential replacements for soil steaming in organic and other low-input tomato production systems. When only Pyrenochaeta lycopersici and/or Meloidogyne spp. were present in soil, grafting and/or chitin soil amendment were found to be as effective in reducing root disease and/or increasing yield as soil steaming, but the efficacy of both treatments was reduced when Verticillum albo-atrum was also present in soil. No additive effects of combining grafting and chitin soil amendments could be detected. A more widespread use of grafting and/or chitin soil amendments may therefore allow significant reductions in the use of steam and chemical soil disinfestation in glasshouse crops. It will also allow integrated and organic farming standard-setting bodies to impose further restrictions on the use of soil disinfestation treatments.     

Integrated Evaluation of Scrotal Temperature and Testosteronemia after GnRH Administration in Young Bulls with Low Semen Production

The aim of this study was to determine the suitability of thermographic monitoring of scrotal surface temperature (SST) as a method to monitor testicular function. Yearling bulls (n = 23) with low semen production were selected. Scrotal surface temperature and serum testosterone (T) concentrations were evaluated before and after administration of 10.5 μg buserelin acetate IV. Thermographic images of scrotum were recorded at 0, 15, 30, 45 and 60 min post‐GnRH, while blood sampling was only performed at 60 min post‐GnRH. Bulls were divided in two groups: LowTemp bulls (n = 10) had a decreased SST at 60 min; HighTemp bulls (n = 13) had an increased SST. After 60 min, LowTemp bulls had higher T concentrations compared to HighTemp bulls: 14.32 ng/ml ± 0.53 vs 10.30 ± 1.37 ng/ml (mean ± SEM; p < 0.05), respectively. Reproductive performances in both groups improved after GnRH administration, resulting in an increased number of inseminating doses from each collection, which was higher in LowTemp bulls. Pearson correlation test showed a negative relationship between T and SST (r = ?0.554). In conclusion, a decreased scrotal surface temperature 60 min after GnRH treatment was associated with improved semen production.     

Use of Oil Red O stain in the cytologic diagnosis of canine liposarcoma

BACKGROUND: Oil Red O, a stain commonly used to demonstrate lipid in frozen tissue, also may be used to stain air-dried cytologic specimens. OBJECTIVE: The purpose of this study was to prospectively evaluate the value of Oil Red O in identifying lipid to aid in the differentiation of liposarcomas from other types of sarcoma. METHODS: Twelve tumor specimens from dogs were evaluated. The tumors were included in the study if initial cytologic evaluation indicated a sarcoma, and if histologic confirmation was available. Oil Red O was applied to all cytologic specimens. RESULTS: Tumor specimens were diagnosed histologically as liposarcoma (3 well-differentiated, 1 pleomorphic), hemangiopericytoma (n = 3), fibrosarcoma (n = 3), malignant fibrous histiocytoma (n = 1), and undifferentiated sarcoma (n = 1). Cytologic specimens from all liposarcomas showed strong positive staining of cytoplasmic vacuoles for lipid. Specimens from other sarcomas stained negative for Oil Red O, with the exception of weak, irregular positive staining in 1 hemangiopericytoma. CONCLUSION: Our results suggest that Oil Red O staining may be an easy, inexpensive, and useful diagnostic tool for the differentiation of liposarcoma from other mesenchymal neoplasms.     

Primed N2O emission from native soil nitrogen: A 15N‐tracing laboratory experiment

Soils can naturally be a source of the potent greenhouse gas nitrous oxide (N₂O). By contrast, the largest anthropogenic source of N₂O is the application of nitrogen (N) fertilizer on agricultural soil, but it is unclear if fertilizer‐supported N₂O emission only originates from the fertilizer N directly or through additionally stimulated N₂O production from native soil N. Even though native soil N also includes mineral N already in soil before fertilizer application, organic N is the principal native N pool and thereby provides for mineral N cycling and N₂O emission. Here, we tested (1) the contribution of native soil N to N₂O emission after mineral N fertilizer application and (2) whether it is affected by different soil organic matter (SOM) contents by conducting a laboratory ¹⁵N‐tracing experiment with agricultural soil from a long‐term field trial with two treatments. Both field treatments are fertilized with mineral N, whereas only one of the two receives liquid manure causing higher SOM content. Soil sampling was conducted in March 2016 shortly before fertilizer application in the field. The application of ¹⁵N‐labeled fertilizer more than doubled the N₂O production from native N sources compared to the non‐fertilized control incubations. This primed N₂O production contributed by 5–8% to the fertilizer‐induced N₂O emission after one week of incubation and was similar for both field treatments regardless of liquid manure application. Therefore, further research is needed to link N₂O priming to its potential production pathways and sources. While the observed effect may be important in soils, the amount of applied N fertilizer remains the largest concern being responsible for the majority of N₂O emission.