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1.
Laura Santagostini Elisabetta Caporali Claudia Giuliani Martina Bottoni Roberta Ascrizzi Silvia R. Araneo 《Plant biosystems》2020,154(3):316-325
AbstractSeveral aroma hops (Humulus lupulus L.) were recently introduced in Northern Italy as a small-scale production of excellence. In this preliminary study, the American cultivar Cascade was investigated in a combined morphological and phytochemical survey. Morphological investigation on trichome structure, density and distribution was performed by scanning electron microscopy and light microscopy. Essential oil composition, α/β-acid and polyphenol profiles over 3 years were determined by GC-MS and HPLC analyses. Two types of non-glandular (simple and cystolithic) and glandular (peltate and bulbous) trichomes were observed on leaves and female inflorescences. The peltate trichomes resulted as the main sites of terpene production and accumulation. The essential oil profiles showed myrcene, β-caryophyllene, (E)-β-farnesene and humulene epoxide II as the dominant compounds over the three collection times, although with different relative abundances. The presence of two exclusive compounds, γ-muurolene and trans-γ-cadinene, characterized the investigated cv. Cascade, potentially enhancing herbal, woody and spicy aroma traits of this cultivation in Northern Italy. The bitter acid composition showed quantitative values consistent with literature data only for the second and third monitoring year. Qualitative differences in polyphenol content were also recorded, for the presence of quercetin-3-O-malonylglucoside and kaempferol-3-O-rutinoside, which may characterize this peculiar Italian cultivation. 相似文献
2.
Torkel Wadström Siiri Hirmo Hajdi Novak Antonio Guzman Martina Ringnér-Pantzar Meeme Utt Pär Aleljung 《Current microbiology》1997,34(5):267-272
Helicobacter pylori adhere to Kato III and Hela S3
cells in monolayer cultures. To explore whether cell surface glycoconjugates
on these two cell lines mediate binding of H. pylori, various
carbohydrates, glycoproteins, and glycolipids were tested to inhibit H.
pylori cell adhesion. The adhesion was measured (i) with a urease-based
assay and (ii) by cells stained with fluorescein. Sodium periodate and
sialidase treatment (but not α- or β-galactosidase, heparitinase,
lysozyme, or trypsin) inhibited H. pylori binding to both cell lines.
Sulfatides and sulfated glycoconjugates (50 μg/ml) but not heparin or a
number of simple carbohydrates inhibited binding (1 mg/ml). The two H.
pylori strains studied (CCUG 17874 and strain 25) showed high binding of
soluble 125I-labeled heparin and other sulfated carbohydrate
compounds.
Received: 5 July 1996 / Accepted: 17 October 1996 相似文献
3.
Schuster Martina Tewary Gargi Bao Xuanwen Subedi Prabal Hauck Stefanie M. Olsen Ann Karin Eide Dag Markus Trott Klaus Rüdiger Götz Sebastian Atkinson Michael J. Rosemann Michael 《Radiation and environmental biophysics》2021,60(4):689-689
Radiation and Environmental Biophysics - 相似文献
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In isolated rat liver cells, ethanol inhibited gluconeogenesis from xylitol and sorbitol but not from fructose. Acetaldehyde, at initial concentrations of 0.2, 0.5, and 1.0 mm, stimulated gluconeogenesis from xylitol and sorbitol in the absence of pyrazole but inhibited in the presence of pyrazole. There was no effect with fructose. Acetate had no effect. Methylene blue and pyruvate (but not lactate) prevented the stimulatory as well as the inhibitory effects of acetaldehyde. Acetoacetate (but not β3-hydroxybutyrate) prevented, to a large extent, the inhibitory effects of low (but not high) concentrations of acetaldehyde. The inhibition by low concentrations of acetaldehyde appears to be mediated via acetaldehyde oxidation in the mitochondria, whereas the inhibition by high concentrations of acetaldehyde appears to reflect acetaldehyde oxidation in the cytosol. These data indicate that the inhibitory action of ethanol on glucose production from xylitol and sorbitol can be reproduced by physiological concentrations of acetaldehyde. Changes in the ratio produced during acetaldehyde metabolism appear to be responsible for these effects of acetaldehyde. These changes may contribute to the actions of ethanol on gluconeogenesis from these substrates. 相似文献
7.
Stanislav Lhota Veronika Roubov Vendula Gregorov Martina Kone
n 《American journal of primatology》2019,81(9)
Grooming in primates is often considered a “currency” that can be exchanged for other “services” or “commodities” such as reciprocal grooming, coalitionary support, infant handling, tolerance around food sources, active food sharing, or mating opportunities. Previous studies on primate grooming‐for‐sex exchange viewed the males as the demanding class, with the females as suppliers of mating opportunities. In this study, we examine the broader context of grooming‐for‐mating exchange in Barbary macaques in Gibraltar. Our data show that Barbary macaque males groom females with whom they are mating more frequently and for longer periods than other females, and the relationship between grooming and mating remains significant in both sexual and nonsexual contexts. In addition, females groomed males with whom they were mating more frequently and for longer periods than other males. In both sexes, grooming was observed to be far more frequent and to occur for longer durations in sexual compared to nonsexual contexts. We did not find any difference in grooming behavior between presexual and postsexual contexts. Our data suggest that there is no simple model to describe Barbary macaque grooming patterns in sexual contexts. Although our results are partly consistent with male use of grooming as payment for mating, broadly assessed grooming‐mating patterns cannot be solely explained by a male‐driven grooming‐for‐mating exchange. 相似文献
8.
Discovery of a Novel Insect Neuropeptide Signaling System Closely Related to the Insect Adipokinetic Hormone and Corazonin Hormonal Systems 总被引:1,自引:0,他引:1
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Olivia Sackett Katherina Petrou Brian Reedy Ross Hill Martina Doblin John Beardall Peter Ralph Philip Heraud 《The ISME journal》2016,10(2):416-426
Diatoms, an important group of phytoplankton, bloom annually in the Southern Ocean, covering thousands of square kilometers and dominating the region''s phytoplankton communities. In their role as the major food source to marine grazers, diatoms supply carbon, nutrients and energy to the Southern Ocean food web. Prevailing environmental conditions influence diatom phenotypic traits (for example, photophysiology, macromolecular composition and morphology), which in turn affect the transfer of energy, carbon and nutrients to grazers and higher trophic levels, as well as oceanic biogeochemical cycles. The paucity of phenotypic data on Southern Ocean phytoplankton limits our understanding of the ecosystem and how it may respond to future environmental change. Here we used a novel approach to create a ‘snapshot'' of cell phenotype. Using mass spectrometry, we measured nitrogen (a proxy for protein), total carbon and carbon-13 enrichment (carbon productivity), then used this data to build spectroscopy-based predictive models. The models were used to provide phenotypic data for samples from a third sample set. Importantly, this approach enabled the first ever rate determination of carbon productivity from a single time point, circumventing the need for time-series measurements. This study showed that Chaetoceros simplex was less productive and had lower protein and carbon content during short-term periods of high salinity. Applying this new phenomics approach to natural phytoplankton samples could provide valuable insight into understanding phytoplankton productivity and function in the marine system. 相似文献