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81.
Detection and phylogenetic characterization of astroviruses in insectivorous bats from Central‐Southern Italy
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Maria Grazia Amoroso Danilo Russo Gianvito Lanave Luca Cistrone Annamaria Pratelli Vito Martella Giorgio Galiero Nicola Decaro Giovanna Fusco 《Zoonoses and public health》2018,65(6):702-710
In recent years, bats have been found to harbour many viruses, raising several questions about their role as reservoirs and potential disseminators of zoonotic viruses. We investigated the presence of six virus families in bats in three regions of Central‐Southern Italy. Astroviruses were identified in seven of 13 bat species. Sequence analysis revealed marked genetic heterogeneity among the astroviruses identified, with nucleotide identity ranging between 60.26% and 87.62%. Astrovirus diversity was not associated with the bat species, the geographic areas or the bat colony, suggesting the circulation of several astrovirus strains in Italian ecosystems. Genetic diversification and interspecies transmission appear common in bat astroviruses and could provide, potentially, the bases for transmission to humans and other mammals. Yet overemphasizing this risk might have detrimental consequences for bat conservation and preservation of the important ecosystem services bats provide. 相似文献
82.
Tullio Venditti Antonio Dore Maria Giovanna Molinu Mario Agabbio Guy Dhallewin 《Postharvest Biology and Technology》2009,54(2):111-114
In recent years several alternatives to the chemical control of postharvest decay have been examined but satisfactory levels of control, with a single system, have not been achieved yet. In the present study the results of an integrated postharvest approach are reported. Early and late harvested hybrid mandarin fruit “Fremont” and “Fairchild”, inoculated with Penicillium digitatum (Pers.:Fr.) Saccardo, were cured at 36 °C for 36 h with 95% RH and then fumigated with 0, 5, 15, 25, 50, 75 and 100 μL/L of acetic acid (AAC) vapours for 15 min. Following the treatments, fruit was stored at 20 °C and 80% RH to simulate a marketing period, and after 2 weeks the decay incidence and the visual appearance were evaluated. Curing or fumigations performed alone reduced decay with respect to untreated fruit, but the best control was achieved with combined treatments. For early harvested fruit the lowest decay percentage was obtained by using 75 μL/L with 8.3% and 2.1% of rots for “Fremont” and “Fairchild”, respectively, whereas for late harvested fruit the highest efficacy was observed using 50 μL/L (1.4% and 6.6%). Rind damage as pitting was observed only if fruit was treated with AAC alone at 100 μL/L. 相似文献
83.
Servillo L Giovane A Balestrieri ML Ferrari G Cautela D Castaldo D 《Journal of agricultural and food chemistry》2012,60(1):315-321
The presence of pipecolic acid and pipecolic acid betaine, also known as homostachydrine, is herein reported for the first time in Citrus genus plants. Homostachydrine was found in fruits, seeds, and leaves of orange, lemon, and bergamot (Citrus bergamia Risso et Poit). As homostachydrine was not commercially available, as a comparative source, extracts of alfalfa leaves ( Medicago sativa L.) were used, in which homostachydrine is present at high concentration. Then, the results where confirmed by comparison with an authentic standard synthesized and purified starting from pipecolic acid. The synthesized standard was characterized by a ESI-MS/MS study using a 3D ion-trap mass spectrometer. When subjected to MS/MS fragmentation in positive ion mode, homostachydrine, unlike its lower homologue proline betaine (also known as stachydrine), showed a pattern of numerous ionic fragments that allowed unambiguous identification of the compound. For the quantitation in the plant sources, high sensitivity and specificity were achieved by monitoring the transition (158 → 72), which is absent in the fragmentation patterns of other major osmolytes commonly used as markers for studies of abiotic stress. As for the metabolic origin of homostachydrine, the occurrence in citrus plants of pipecolic acid leads to the hypothesis that it could act as a homostachydrine precursor through direct methylation. 相似文献
84.
85.
Plectosphaerella cucumerina has been described recently as the causal agent of a leaf spot on wild rocket (Diplotaxis tenuifolia). Eight seed samples of wild rocket obtained from commercial seed lots used for sowing by farms severely affected by P. cucumerina, were assayed for the presence of the pathogen. Isolations were carried out on subsamples of seeds (400) unwashed or disinfected in 1% sodium hypochloride. The pathogenicity of the isolates of P. cucumerina obtained was tested in two trials carried out on wild rocket; four out of eight samples of rocket seeds were contaminated by P. cucumerina. Eleven isolates of P. cucumerina were obtained from 7,200 not disinfected seeds tested, while none was isolated from an equal number of disinfected seeds. All isolates were pathogenic on wild rocket. The results obtained indicate that rocket seeds are a potential source of inoculum for P. cucumerina. The possibility of isolating the pathogen from seeds, albeit from a low percentage of them, supports the hypothesis that the rapid spread of this new disease of rocket recently observed in Italy is due to the use of infected propagation material. Measures for prevention and control of the disease are discussed. 相似文献
86.
Ianora A Bentley MG Caldwell GS Casotti R Cembella AD Engström-Öst J Halsband C Sonnenschein E Legrand C Llewellyn CA Paldavičienë A Pilkaityte R Pohnert G Razinkovas A Romano G Tillmann U Vaiciute D 《Marine drugs》2011,9(9):1625-1648
Marine chemical ecology comprises the study of the production and interaction of bioactive molecules affecting organism behavior and function. Here we focus on bioactive compounds and interactions associated with phytoplankton, particularly bloom-forming diatoms, prymnesiophytes and dinoflagellates. Planktonic bioactive metabolites are structurally and functionally diverse and some may have multiple simultaneous functions including roles in chemical defense (antipredator, allelopathic and antibacterial compounds), and/or cell-to-cell signaling (e.g., polyunsaturated aldehydes (PUAs) of diatoms). Among inducible chemical defenses in response to grazing, there is high species-specific variability in the effects on grazers, ranging from severe physical incapacitation and/or death to no apparent physiological response, depending on predator susceptibility and detoxification capability. Most bioactive compounds are present in very low concentrations, in both the producing organism and the surrounding aqueous medium. Furthermore, bioactivity may be subject to synergistic interactions with other natural and anthropogenic environmental toxicants. Most, if not all phycotoxins are classic secondary metabolites, but many other bioactive metabolites are simple molecules derived from primary metabolism (e.g., PUAs in diatoms, dimethylsulfoniopropionate (DMSP) in prymnesiophytes). Producing cells do not seem to suffer physiological impact due to their synthesis. Functional genome sequence data and gene expression analysis will provide insights into regulatory and metabolic pathways in producer organisms, as well as identification of mechanisms of action in target organisms. Understanding chemical ecological responses to environmental triggers and chemically-mediated species interactions will help define crucial chemical and molecular processes that help maintain biodiversity and ecosystem functionality. 相似文献
87.
88.
Rubiolo P Matteodo M Riccio G Ballero M Christen P Fleury-Souverain S Veuthey JL Bicchi C 《Journal of agricultural and food chemistry》2006,54(20):7556-7563
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. 相似文献
89.
Edoardo Capuano Giovanna Garofalo Aurora Napolitano Henryk Zielinski Vincenzo Fogliano 《Cereal Chemistry》2010,87(2):131-136
This report shows the effect of rye flour extraction rate on Maillard reaction, antioxidant activity, and acrylamide formation during toasting of rye bread crisps. Four rye flours with extraction rates of 70, 85, 95, and 100% were tested. Maillard reaction development was studied by measuring browning development, hydroxymethylfurfural (HMF), and glucosilisomaltol (GIM) formation, as well as antioxidant activity. Results showed that HMF and GIM concentrations in toasted bread crisps were higher as the flour extraction rate increases. Antioxidant activity increased during toasting as a consequence of antioxidant Maillard reaction product formation. Acrylamide concentration was clearly affected by free asparagine content of flour, while no effect of dietary fiber and natural antioxidant content of flours had an effect on acrylamide formation. Overall data suggest that the rate of Maillard reaction is higher in whole flours because of their higher free amino acid and protein content. 相似文献
90.
Angelo Garibaldi Giovanna Gilardi Ettore Erik Cogliati Maria Lodovica Gullino 《European journal of plant pathology / European Foundation for Plant Pathology》2012,132(1):123-132
Downy mildew of lettuce, caused by Bremia lactucae, is difficult to control in soilless systems by using conventional methods of disease management because few chemicals are
registered, while resistant cultivars face the problem of resistance break down; therefore other methods for disease control
need to be investigated. The effect of silicon salt as well as increased electrical conductivities against downy mildew was
evaluated in four experiments carried out in hydroponically systems, using the cultivar of lettuce “Cobham Green”, known for
its susceptibility to the pathogen. Silicon, as potassium silicate, was added at 100 mg l−1 of nutrient solution at three levels of electrical conductivity: 1.5–1.6 mS cm−1 (EC1), 3.0–3.5 mScm−1 (EC2, 0.70 g l−1 NaCl) and 4.0–4.5 mS cm−1 (EC3, 0.95 g l−1 NaCl) respectively. Lettuce plants, grown for 14–20 (trials 1 and 2) and 36–45 (trials 3 and 4) days in the different nutrient
solutions tested, were inoculated with B. lactucae conidia with a maximum of two inoculations before final disease assessment carried out 14–21 days after the inoculation able
to give symptoms. EC and potassium silicate significantly influenced downy mildew incidence and severity, while their interaction
was not a significant factor. The addition to the standard nutrient solution (EC1) of potassium silicate resulted in a significant
reduction of downy mildew severity in trials 1 and 2 where plants were artificially inoculated 15 and 20 days after transplanting.
This efficacy was slight on plants grown for 36 and 45 days before inoculation in a soil drenched with EC1 amended with potassium
silicate. EC2 gave a significantly similar downy mildew reduction than EC2 added with potassium silicate in trial 3. Plants
grown for 36 and 45 days at the highest electrical conductivity (EC3) showed a significant reduction in severity of downy
mildew compared with that observed at EC2 level. The best results, in terms of disease control, were given by the addition
of potassium silicate to the EC3 solution. This combination also led to a significantly increased plant biomass. The possibility
and benefits of applying potassium silicate and increased EC amendments in practice is discussed. 相似文献