Search results for "Polyp"
showing 10 items of 1415 documents
Recovery of bioactive compounds from walnut (Juglans regiaL.) green husk by supercritical carbon dioxide extraction
2021
In this work, the use of supercritical carbon dioxide, a nontoxic solvent, was proposed to extract bioactive compounds from Juglans regia L. green husk and was compared to other traditional techniques based on solvents such as ethanol, methanol and water. Supercritical CO2 was combined with ethanol as an organic modifier at a rate of 20% of the total flow to achieve greater extraction of polar compounds. The extracts were characterised in terms of extraction yields, antioxidant activity, total polyphenol content, phenolic acids, juglone, volatile organic compounds and antifungal activity. The results showed that the extracts obtained with supercritical CO2 were rich in polyphenols (10750 mg…
Are homalozoans echinoderms? An answer from the extraxial-axial theory
2000
Homalozoans include four classes of non-pentamerous Paleozoic echinoderms: Homostelea (cinctans), Ctenocystoidea (ctenoid-bearing homalozoans), Homoiostelea (solutes), and Stylophora (cornutes and mitrates). Their atypical morphologies have historically made it difficult to relate them to other classes. Therefore, their systematic positions have been represented by two hypotheses (H): as stem taxa to echinoderms (H1) or as stem taxa to chordates (H2). These conclusions rest on previous inability to recognize synapomorphies with more crownward echinoderms, resulting in a forcing of the homalozoans down the phylogenetic tree that is more artifactual than evolutionary. The Extraxial-Axial Theo…
18S rDNA phylogeny and evolution of cap development in Polyphysaceae (formerly Acetabulariaceae; Dasycladales, Chlorophyta)
2003
Abstract Cells of the members of the Dasycladales have a unique body plan well known from fossils. They persist today in 38 recognized species. This study investigates in detail the development of reproductive structures in 17 Polyphysaceae (= Acetabulariaceae) species and provides a molecular phylogenetic analysis of 18S ribosomal DNA sequence data of 23 species of the order Dasycladales, including 17 of the 19 extant members of the family Polyphysaceae. Reproductive cap development is documented by scanning electron microscopy in 17 species, by histological sections in five species, and by growth measurements. Other morphometric data are also provided for most species. Bayesian analysis o…
Classification and Phylogeny of the Triatominae
2010
Publisher Summary Perhaps the greatest challenge for the classification of Triatominae is the lack of a unifying concept of species. To discuss some of the conflicts that arise from applying modern concepts to traditional classification, and to highlight some recurrent practices regarding the systematics of the subfamily, this chapter develops this discussion in parallel with the traditional and modern concepts of species. In understanding biodiversity, one must understand that taxonomy and systematics work together, although the two terms are often confused. Divergence between the modern concepts of systematics starts at the definition given to the taxa they wish to analyze: single individ…
Influence of Two Different Coating Application Methods on the Maintenance of the Nutritional Quality of Fresh-Cut Melon during Storage
2021
This study aimed at evaluating the effects of two coating application methods, spraying and dipping, on the quality of fresh-cut melons. An alginate-based coating containing both ascorbic and citric acid was applied at two concentrations (5% and 10%) with both methods on fresh-cut melon. The nutritional quality of the products was investigated during 11 days of storage at 10 °C. The suitability and adaptability of the applied coatings on the fruit were evaluated based on rheological and microstructural properties. Moisture, carotenoids, total polyphenols and ascorbic acid content were analyzed on melon samples during storage. Results showed that the coating solution applied by the dipping m…
Optimization of Polyphenols' Recovery from Purple Corn Cobs Assisted by Infrared Technology and Use of Extracted Anthocyanins as a Natural Colorant i…
2022
An ecofriendly extraction technology using infrared (IR) irradiation Ired-Irrad® was applied to purple corn cobs to enhance polyphenol recovery for the first time. The IR extraction efficiency was compared to that of the water bath (WB) method. Response surface methodology (RSM) using a central composite design was conducted to determine the effect of the experimental conditions (extraction time and treatment temperature) and their interactions on the total polyphenol and anthocyanin yields. Optimal extraction of total phenolic compounds (37 mg GAE/g DM) and total monomeric anthocyanins (14 mg C3G/g DM) were obtained at 63 °C for 77 min using IR as an extraction technique and water as a sol…
Modulation of intracellular calcium concentrations and T cell activation by prickly pear polyphenols.
2004
Opuntia ficus indica (prickly pear) polyphenolic compounds (OFPC) triggered an increase in [Ca2+]i in human Jurkat T-cell lines. Furthermore, OFPC-induced rise in [Ca2+]i was significantly curtailed in calcium-free buffer (0% Ca2+) as compared to that in 100% Ca2+ medium. Preincubation of cells with tyrphostin A9, an inhibitor of Ca2+ release-activated Ca2+ (CRAC) channels, significantly diminished the OFPC-induced sustained response on the increases in [Ca2+]i. Lanthanum and nifedipine, the respective inhibitors of voltage-dependent and L-type calcium channels, failed to curtail significantly the OFPC-induced calcium response. As OFPC still stimulated increases in [Ca2+]i in 0% Ca2+ medium…
Synthesis and Characterization of Palladium Nanoparticle/Polypyrrole Composites
2008
In this work, a simple non-template one-step method for the synthesis of 2.0−2.5 nm palladium nanoparticles encapsulated into a polypyrrole shell via direct redox reaction between palladium(II) acetate and pyrrole in acetonitrile medium is described. Palladium nanoparticles are found to be able to self-organize into spherical Pd/PPy composites. The size of the Pd/PPy composite particles and Pd content in the composite depend strongly on the concentration of the palladium salt component. The combination of elemental CHNS and thermogravimetric (TGA) analysis was used to determine a high (∼40 wt %) content of palladium, which is in a good agreement with EDX data. The process of Pd/PPy composit…
Thermal Stability and Flame Retardancy of Polypropylene Composites Containing Siloxane-Silsesquioxane Resins
2018
A novel group of silsesquioxane derivatives, which are siloxane-silsesquioxane resins (S4SQ), was for the first time examined as possible flame retardants in polypropylene (PP) materials. Thermal stability of the PP/S4SQ composites compared to the S4SQ resins and neat PP was estimated using thermogravimetric (TG) analysis under nitrogen and in air atmosphere. The effects of the non-functionalized and n-alkyl-functionalized siloxane-silsesquioxane resins on thermostability and flame retardancy of PP materials were also evaluated by thermogravimetry-Fourier transform infrared spectrometry (TG-FTIR) and by cone calorimeter tests. The results revealed that the functionalized S4SQ resins may for…
Chromatogrphic Profiles of Polyphenols and Terpenoids in the Herbs of Some Thymus L. Represntatives
2022
The aim of the work. To perform the identification of phenolic compounds and terpenoids in the aerial parts of Thymus pulegioides L. (cultivar ‘2/6-07’), Thymus richardii Pers. (cultivar 'Fantasy') and Thymus vulgaris L. (cultivar ‘Jalos’) using thin layer chromatography (TLC), as well as to conduct the gaschromatographic analysis of Thymus richardii essential oil. Materials and Methods. The TLC method was used in this study for the qualitative analyses of polyphenols and non-polar compounds in the aerial part of three Thyme (Thymus L.) species from the Lamiaceae Martinov family cultivated in Kherson region (Ukraine). The volatile compounds were determined in the essential oil of Thymus ric…