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71.
Rocco Latorre Maurizio Mazzoni Roberto De Giorgio Claudia Vallorani Alessio Bonaldo Pier Paolo Gatta Roberto Corinaldesi Eugenio Ruggeri Chiara Bernardini Roberto Chiocchetti Catia Sternini Paolo Clavenzani 《Fish physiology and biochemistry》2013,39(6):1555-1565
In vertebrates, chemosensitivity of nutrients occurs through the activation of taste receptors coupled with G-protein subunits, including α-transducin (Gαtran) and α-gustducin (Gαgust). This study was aimed at characterising the cells expressing Gαtran immunoreactivity throughout the mucosa of the sea bass gastrointestinal tract. Gαtran immunoreactive cells were mainly found in the stomach, and a lower number of immunopositive cells were detected in the intestine. Some Gαtran immunoreactive cells in the stomach contained Gαgust immunoreactivity. Gastric Gαtran immunoreactive cells co-expressed ghrelin, obestatin and 5-hydroxytryptamine immunoreactivity. In contrast, Gαtran immunopositive cells did not contain somatostatin, gastrin/cholecystokinin, glucagon-like peptide-1, substance P or calcitonin gene-related peptide immunoreactivity in any investigated segments of the sea bass gastrointestinal tract. Specificity of Gαtran and Gαgust antisera was determined by Western blot analysis, which identified two bands at the theoretical molecular weight of ~45 and ~40 kDa, respectively, in sea bass gut tissue as well as in positive tissue, and by immunoblocking with the respective peptide, which prevented immunostaining. The results of the present study provide a molecular and morphological basis for a role of taste-related molecules in chemosensing in the sea bass gastrointestinal tract. 相似文献
72.
CM Donado-Pestana JM Salgado A de Oliveira Rios PR Dos Santos A Jablonski 《Plant foods for human nutrition (Dordrecht, Netherlands)》2012,67(3):262-270
Intervention strategies regarding the biofortification of orange-fleshed sweet potato, which is a rich source of carotenoids for combating vitamin A deficiency, are being developed in Brazil. This study was conducted to evaluate the concentrations of individual carotenoids, total phenolic compounds and antioxidant capacity in the roots of four biofortified sweet potato cultivars that were raw or processed by four common heat treatments. HPLC, Folin-Ciocalteu, DPPH and ABTS assays were used. All cultivars showed high levels of carotenoids in raw roots, predominantly all-trans-β-carotene (79.1-128.5?mg.100?g(-1) DW), suggesting a high estimated vitamin A activity. The CNPH 1194 cultivar reported carotenoids values highest than those of other cultivars (p?0.05). The total phenolic compounds varied among cultivars and heat treatments (0.96-2.05?mg.g(-1) DW). In most cases, the heat treatments resulted in a significant decrease in the carotenoids and phenolic compounds contents as well as antioxidant capacity. Processing of flour presented the greatest losses of major carotenoids and phenolics. The phenolic compounds showed more stability than carotenoids after processing. There were significant correlations between the carotenoids and phenolic compounds and the antioxidant capacity. 相似文献
73.
Gianluigi Mazza Alessandro Elio Agnelli Maria Costanza Andrenelli Alessandra Lagomarsino 《Archives of Agronomy and Soil Science》2018,64(5):654-667
GHGs production and emission may vary depending on soil physical properties, water management and fertilization. Two paddy soils characterized by different texture were incubated to evaluate the impact of flooding (permanent or intermittent) and N addition on potential N2O, CH4 and CO2 production and release into atmosphere and soil solution. Relationships with volumetric water content (VWC) and water filled pore space (WFPS) were evaluated. Overall, the finer clayey soil (CL) produced 58% more CH4 than the coarser sandy soil (SA) and showed an earlier sink to source transition; the difference was lower with N addition. Permanent flooding favoured the amount of dissolved CH4. SA produced more N2O emissions than CL under permanent flooding (31.0 vs. 3.7%); an opposite pattern was observed for dissolved N2O (16.4 vs. 52.7%). Fertilization increased N2O emissions under dry conditions in CL and under flooding in SA.
Our findings showed that i) VWC had a larger influence on N2O and CH4 emissions than WFPS, ii) soil type influenced the gas release into atmosphere or soil solution and the timing of sink to source transition in CH4 emissions. Further investigation on timing of fertilization and drainage are needed to improve climate change mitigation strategies. 相似文献
74.
Romildo Rocha Azevedo Junior Janaina Biral dos Santos Dilmar Baretta Alessandro Coutinho Ramos Arthur Prudêncio de Araujo Pereira Elke Jurandy Bran Nogueira Cardoso 《Journal of plant nutrition》2017,40(14):2076-2086
The goal of this study was to evaluate the effect of organic (OS) and conventional (CS) farming of Arabica coffee on chemical and microbiological soil properties and to identify which attributes correlate and/or contribute to distinguishing these two management systems. We collected soil samples on a 100 × 100 m2 grid in both, the OS and CS, in winter and summer and submitted chemical and microbiological properties to univariate and multivariate analyses (canonical discriminant analysis – CDA – and redundancy analysis – RDA). The best indicators to discriminate OS and CS were chemical and microbiological properties, as the elements calcium (Ca) and boron (B), besides microbial biomass carbon (MBC), metabolic quotient (qCO2), acid phosphatase (ACP), and alkaline phosphatase (ALP). The RDA showed that, regardless of the season, MBC and ACP correlated with nitrogen (N), sulfur (S) and organic matter (OM), whereas basal respiration (C-CO2) and ACP correlated with qCO2 and with magnesium (Mg), calcium (Ca), phosphorus (P), potassium (K) and pH. 相似文献
75.
Ballabio C Magni C Restani P Mottini M Fiocchi A Tedeschi G Duranti M 《Plant foods for human nutrition (Dordrecht, Netherlands)》2010,65(4):396-402
The immunological cross-reactivity among major protein- and oil-crops, including lupin, lentil, pea, peanut, kidney bean and
soybean, has been studied by a combination of in vitro and in vivo experimental approaches: SDS-PAGE separations of legume protein extracts and immuno-blot revelations with 12 peanut-sensitive
subjects’ sera, Immuno-CAP and Skin Prick tests on the same subjects. The immuno-blotting data showed a wide range of IgE-binding
responses both displayed by one subject towards different plant extracts and among subjects. Differences were both quantitative
and qualitative. The prevalent responses of most subjects’ sera were seen with peanut polypeptides, as expected, as well as
with various polypeptides of the other legumes, the most recurrent of which were the basic subunits of the 11S globulins.
The distribution of in vivo responses generally paralleled those obtained by in vitro approaches with strong responses elicited by peanut, lentil and pea protein extracts, especially by most sensitive subjects,
thus providing a consistent overall set of results. In this work, the comparison of various approaches has allowed us to get
an overall broad picture of the immunological cross-reactivities among proteins of widely used different seed species and
to hypothesize the role of most conserved specific polypeptides. 相似文献
76.
Pereira MC Steffens RS Jablonski A Hertz PF Rios Ade O Vizzotto M Flôres SH 《Journal of agricultural and food chemistry》2012,60(12):3061-3067
The objective of this study is to evaluating the Brazilian biodiversity through physicochemical characterization and determination of antioxidant potential of three species from the Myrtaceae family, namely yellow guava (Psidium cattleyanum Sabine), guabiroba (Campomanesia xanthocarpa O. Berg), and uvaia ( Eugenia pyriformis Cambess). Guabiroba had the greater quantity of phenolic compounds (9033 mg chlorogenic acid/100 g) and vitamin C (30.58 mg/g) and showed the best TSS/TTA (total soluble solid/total titratable acid) ratio (45.12). For the ABTS (2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic) method, the guabiroba (507.49 μM Trolox/g) presented the highest antioxidant potential; however, in the DPPH (2,2-diphenyl-1-picrylhydrazyl) method, uvaia (170.26 g/g DPPH) and guabiroba (161.29 g/g DPPH) were not statistically different. The uvaia outranked the other fruits with respect to its high carotenoid (909.33 μg/g) and vitamin A (37.83 μg/g) contents, and the yellow guava, although showing a lower bioactive compound content and antioxidant activity, nevertheless presented much higher values than many traditionally consumed fruits. 相似文献
77.
Daniela Gargano Nunzia Scotti Alessandro Vezzi Alessandra Bilardi Giorgio Valle Stefania Grillo Salvatore Cozzolino Teodoro Cardi 《Genetic Resources and Crop Evolution》2012,59(3):419-430
The plastome sequence of the European cultivated potato, Solanum tuberosum subsp. tuberosum (tbr, GenBank accession no. DQ386163), was compared with that of S. bulbocastanum, a wild potato relative (blb, GenBank accession no. DQ347958), in order to characterize the degree and type of variability
in different genomic regions, and develop molecular markers relevant to genetics, breeding and biotechnology of potato. One
hundred forty-two and 251 PICs (Potentially Informative Characters) were found in coding and non-coding sequences (NCSs),
respectively. Further, while variation in coding regions was almost exclusively due to nucleotide substitutions, 25% of PICs
in NCSs of tbr and blb were due to indels, most of them mononucleotide or longer tandem repeats (micro and minisatellites).
Four intergenic regions were selected for further analyses in other 16 tuber-bearing Solanum species. The rps16-trnQ
UUG
gene spacer was found to be the most variable, forty-six PICs in this region distinguishing 18 haplotypes. Analysis of haplotype
relationships, based on variability in the four intergenic regions, confirmed that the most primitive species from Central
America were the most distant to S. tuberosum. Finally, polymorphic sites in the same regions were used to develop a set of CAPS (Cleaved Amplified Polymorphic Sequences)
markers for species/cytoplasm identification in Solanum spp. 相似文献
78.
Crustaceans Munida (fam. Galatheideae, ord. Decapodi) were fished in the Southern Adriatic Sea and their proteolytic activities were characterized and tested for potential application in cheese manufacturing. Enzymes extracted from whole crustaceans, mainly serine proteases, showed high caseinolytic and moderate clotting activities. Analysis by 2D zymography of the digestive enzymes extracted from Munida hepatopancreas, showed the presence of several isotrypsin- and isochymotrypsin-like enzymes in the range of 20-34 kDa and 4.1-5.8 pI. Moreover, specific enzymatic assays showed the presence of aminopeptidases and carboxypeptidases A and B. Overall, optimum activity was achieved at pH 7.5 and 40-45 °C. Caseinolytic activity, determined both spectrophotometrically and by SDS gel electrophoresis, indicated higher activity on β-casein than on α-casein. Miniature cheddar-type cheeses and Pecorino-type cheeses were manufactured by adding starter, rennet and Munida extracts to milk. Reverse-phase HPLC and MALDI-ToF mass spectrometry showed a more complex pattern of proteolytic products in cheeses made using Munida instead of chymosin. Munida extracts were found to degrade the chymosin-derived β-casein fragment f193-209, one of the peptides associated with bitterness in cheese. In conclusion, Munida digestive enzymes represent a promising tool for development of new cheese products and shorten cheese ripening when used either alone or in addition to calf rennet. 相似文献
79.
Costagliola A Britti D Russo V Meomartino L Castagna F Giordano D Insabato L Paciello O 《Avian diseases》2011,55(1):147-150
A common seagull (Larus fuscus) was found near the southern coast of Italy by the veterinarians of the local wild animal rescue center. Physical examination of the bird revealed an ulcerated mass involving a majority of the oral cavity; the mass did not allow for normal feeding. After the bird died necropsy was performed and the mass was histologically and immunohistochemically examined. The morphology and the immunoreactivity for Melan-A and S-100 antigens led to a diagnosis of malignant melanoma. This is the first case of malignant melanoma described in a seagull, and herein we compare the characteristics of the present case with malignant melanoma already described in domestic animals. 相似文献
80.