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21.
Kanakis CD Tarantilis PA Tajmir-Riahi HA Polissiou MG 《Journal of agricultural and food chemistry》2007,55(3):970-977
Crocetin (CRT) and dimethylcrocetin (DMCRT) are derived from crocins which are found in the stigmas of saffron (Crocus sativus L.), while safranal is the main component of saffron's essential oil. The aim of the present study was to examine their interaction with human serum albumin in aqueous solution at physiological conditions using constant protein concentration and various ligand contents. FT-IR and UV-visible spectroscopic methods were used to determine the ligands' binding mode, the binding constant, and the effects of ligand complexation on protein secondary structure. Structural analysis showed that crocetin, dimethylcrocetin, and safranal bind nonspecifically (H-bonding) via protein polar groups with binding constants of Kcrt =2.05 (+/-0.30) x 103 M-1, Kdmcrt = 9.60 (+/-0.35) x 104 M-1, and Ksaf = 2.11 (+/-0.35) x 103 M-1. The protein secondary structure showed no major alterations at low ligand concentrations (1 microM), whereas at higher content (1 mM), decrease of alpha-helix from 55% (free HSA) to 43-45% and increase of beta-sheet from 17% (free HSA) to 18-22% and random coil 7% (free HSA) to 10-14% occurred in the ligand-HSA complexes. The results point to a partial unfolding of protein secondary structure at high ligand content. The antioxidant activity of CRT, DMCRT, and safranal was also tested by the DPPH* antioxidant activity assay, and their IC50 values were compared to that of well-known antioxidants such as Trolox and butylated hydroxy toluene (BHT). The IC50 values of CRT and safranal were 17.8 +/- 1 microg/mL and 95 +/- 1 microg/mL, respectively, while the inhibition of DMCRT reached a point of 38.8%, which corresponds to a concentration of 40 microg/mL, and then started to decrease. The IC50 values of Trolox and BHT were 5.2 +/- 1 microg/mL and 5.3 +/- 1 microg/mL, respectively. 相似文献
22.
Waterhouse RM Kriventseva EV Meister S Xi Z Alvarez KS Bartholomay LC Barillas-Mury C Bian G Blandin S Christensen BM Dong Y Jiang H Kanost MR Koutsos AC Levashina EA Li J Ligoxygakis P Maccallum RM Mayhew GF Mendes A Michel K Osta MA Paskewitz S Shin SW Vlachou D Wang L Wei W Zheng L Zou Z Severson DW Raikhel AS Kafatos FC Dimopoulos G Zdobnov EM Christophides GK 《Science (New York, N.Y.)》2007,316(5832):1738-1743
Mosquitoes are vectors of parasitic and viral diseases of immense importance for public health. The acquisition of the genome sequence of the yellow fever and Dengue vector, Aedes aegypti (Aa), has enabled a comparative phylogenomic analysis of the insect immune repertoire: in Aa, the malaria vector Anopheles gambiae (Ag), and the fruit fly Drosophila melanogaster (Dm). Analysis of immune signaling pathways and response modules reveals both conservative and rapidly evolving features associated with different functional gene categories and particular aspects of immune reactions. These dynamics reflect in part continuous readjustment between accommodation and rejection of pathogens and suggest how innate immunity may have evolved. 相似文献
23.
Field performance can be predicted by evaluating nursery stock quality, but optimal morphological variables for use in these assessments may vary by species especially under dry Mediterranean conditions. Our objective was to identify initial seedling morphological characteristics that successfully predict field performance of five Mediterranean species (Pinus halepensis, Quercus ilex, Quercus coccifera, Ceratonia silqua and Pistacia lentiscus). Container seedling morphology was evaluated following the nursery phase, and then seedlings were outplanted in the field where field survival was monitored for two successive years. Results indicate that survival can successfully be predicted from seedling initial morphological characteristics for all these species, yet not all the initial characteristics were good predictors. Survival of P. halepensis and Pist. lentiscus seedlings was positively correlated to initial seedling root-collar diameter, total dry weight and Dickson’s quality index, and can be reliably predicted by these variables. In contrast, seedling field survival of the two Mediterranean evergreen oak species was correlated with few initial morphological attributes; initial diameter provided an accurate index to predict second-year outplanting survival for both species while height/diameter was a good survival predictor for Q. coccifera seedlings. For C. siliqua seedlings, seedlings with larger initial diameter and total biomass survive better in the field. Thus, diameter was the common variable that accurately predicted survival for all species, which should be >5 mm for P. halepensis seedlings and >7 mm for the remaining species. 相似文献
24.
Robert J. Smith Julian Easton Adrian J. Armstrong Sikhumbuzo D. Dlamini Linda Loffler Ara Monadjem Petros Ngwenya Bartolomeu Soto 《Biological conservation》2008,141(8):2127-2138
A number of global priority region schemes have been developed, but local assessments are needed to identify priority areas for conservation within these regions. Here, we describe results from a conservation assessment for Maputaland, part of a biodiversity hotspot in southern Africa that is also the focus of the Lubombo Transfrontier Conservation Area (TFCA) initiative between South Africa, Mozambique and Swaziland. The TFCA seeks to establish new state-, private- and communally-managed conservation areas to boost economic development through nature-based tourism and game ranching. The assessment will guide the TFCA process and used a systematic conservation planning approach to design a landscape to conserve 44 landcover types, 53 species and 14 ecological processes. The assessment also included data on modelled risk of agricultural transformation, of which low-risk areas were selected where possible. The current PA systems in the three countries cover 3830 km2, which represents 21.2% of the region, and meet the representation targets for 46% of the conservation features. The proposed conservation landscape adds 4291 km2 of new core areas and 480 km2 of linkages and, if appropriate, could provide potential revenues of US$18.8 million from game ranching, based on modelled large ungulate density, life history and game auction data. We also discuss the benefits of including data on widely distributed, better known conservation features together with less-well studied, range-restricted species and the advantages of using agricultural transformation risk data in conservation assessments. 相似文献
25.
Yohannes Petros Arnulf Merker Habtamu Zeleke 《Genetic Resources and Crop Evolution》2008,55(3):451-458
Genetic relationships and diversity of 45 Guizotia populations each consisting of ten individuals and belonging to five taxa of the genus Guizotia were analyzed using Inter Simple Sequence Repeat (ISSR) markers. Five ISSR primers generated a total of 145 scorable bands
across the 450 individuals used for the study. The percent polymorphic loci for the taxa ranged from 68.2 (G. arborescens) to 88% (G. scabra ssp. schimperi), with G. scabra ssp. scabra, G. zavattarii and G. villosa following G. scabra ssp. schimperi in this order with respect to the abundance of percent polymorphic loci. The Shannon-Weaver diversity indices (H′), for the
five taxa also followed a similar pattern, with G. scabra ssp. schimperi exhibiting the highest H′ (0.7373) and G. arborescens the least (0.5791), while H′ for G. scabra ssp. scabra, G. villosa and G. zavattarii were 0.7313, 0.6620 and 0.6564, respectively. The least genetic distance (0.1188) was observed between G. scabra ssp. schimperi and G.villosa, revealing closer genetic relationships of the two species with each other than with the others, and the highest genetic
distance (0.2740) was observed between G. scabra ssp. schimperi and G. zavattarii. The unweighted pair group method using the arithmetic average clustering of the five taxa using the standard genetic distances
produced two clusters, with G. scabra ssp. schimperi and G. villosa occurring in one cluster and G. scabra ssp. scabra, G. arborescens and G. zavattarii together in the other cluster. The study reveals that G. scabra ssp. schimperi is more closely related to G. villosa than to G. scabra ssp. scabra. 相似文献
26.
Theofania N. Tsironi Petros S. Taoukis 《Journal Of Aquatic Food Product Technology》2013,22(10):1024-1047
ABSTRACTFish and seafood are food products of high commercial value but with short shelf life. The objective of this article is to review the available packaging techniques and their applications on fish products, focusing on research and latest innovations. Modified atmosphere packaging (MAP) has been investigated for the selection of optimum packaging conditions for different fish products. Recent innovations include the combined application of MAP with other preservative factors, such as minimal processing or the addition of antioxidant and/or antimicrobial compounds. Smart packaging, including active packaging and quality control and monitoring systems (gas and moisture control, antimicrobial/antioxidant packaging, smart labels) and edible films and coatings are innovative packaging technologies, which may result in higher quality and extended shelf life of perishable food. The market for active and intelligent packaging methods is anticipated to rise significantly in the near future with their integration into fish packaging. 相似文献
27.
Y. Petros A. S. Carlsson S. Stymne H. Zeleke A.‐S. Fält A. Merker 《Plant Breeding》2009,128(6):691-695
Oleic acid content was increased from approximately 5–11% to 80–86% in Guizotia abyssinica (L. f.) Cass. materials from Ethiopia after repeated selection and breeding. Achenes collected from Ethiopia were screened for elevated oleic acid content by half seed technique. The starting materials for breeding were nine plants selected from among 272 seeds analysed and having an average oleic acid content of approximately 21% which is considered to be high compared with the 5–11% reported earlier for niger materials of Ethiopian origin. It was observed that the oleic acid content steadily increased after each round of selection and breeding. The percent oleic acid in the seed oil increased to an average of 35.2% and 53.4% after the first and second round of breeding, respectively and ultimately to over 80% after the third round of breeding. It was also observed that the percent oleic acid in the oil stabilizes and the plants breed true when the oleic acid content in the parental seeds was above 79%. 相似文献
28.
Franchi Fulvio Ahad Jason M. E. Geris Josie Jhowa Gaone Petros Alfred K. Comte Jean-Christophe 《Journal of Soils and Sediments》2020,20(3):1632-1650
Journal of Soils and Sediments - The aim of this work was to identify and analyze the records of flood-drought cycles as preserved in the sediments of the Notwane reservoir, southern Botswana, in... 相似文献
29.
Kneknopoulos P Skouroumounis GK Hayasaka Y Taylor DK 《Journal of agricultural and food chemistry》2011,59(3):1005-1011
Anthocyanins and their related compounds were extracted from grape skins of Pinot noir, using 50% aqueous methanol, and purified by solid phase extraction chromatography using XAD-7 resin to obtain a pigment-rich fraction. This fraction was subjected to multilayer coil countercurrent chromatography (MLCCC) using a quaternary solvent system consisting of tert-butyl methyl ether/n-butanol/acetonitrile/water acidified with 0.01% trifluoroacetic acid (2:2:0.1-1.8:5) (v/v/v/v) in a step gradient elution to separate anthocyanin oligomers from grape anthocyanins. In the process of the characterization of the MLCCC fractions by electrospray mass spectrometry, two noncolored anthocyanin derivatives were found and characterized on the basis of their mass spectral data. As a result, these compounds have been tentatively identified as coupling products between both hydrated malvidin-3-glucoside and peonidin-3-glucoside, with 2-S-glutathionyl caffeoyl tartaric acid (GRP). It is therefore proposed that grape skins contain this new class of coupling product, and a possible chemical pathway for their formation is suggested. 相似文献
30.
Morphological and free amino acid profile variability,as a tool for stock identification among farmed rainbow trout Oncorhynchus mykiss of different origin 
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下载免费PDF全文 Petros V Martsikalis Menelaos Kavouras Georgios A Gkafas Apostolos P Apostolidis Ioannis S Boziaris Athanasios Exadactylos 《Aquaculture Research》2018,49(2):621-630
As a tool for stock identification the body morphology and the free amino acid (FAA) profile variability were determined among farmed rainbow trout Oncorhynchus mykiss (Walbaum 1792) from different geographical areas throughout Greece, using geometric morphometrics and Reversed Phase‐High‐Performance Liquid Chromatography. Significant intraspecific body shape variation was detected among the fish stocks of different origin. Canonical Variate Analysis distinguished populations into two groups being consistent to a great extent with a previous population genetics study. General linear models did not support an association of haplotypes and diet with shape. However, shape was significantly correlated with origin, water temperature, geological‐chemical‐climatic zones, histidine and arginine. Therefore, morphological variation was primarily driven by environmentally induced differences among these zones being the result of phenotypic plasticity. Environmental cues and rearing conditions played the pivotal role in comparison to broodstock origin. Specimens presented different FAA profiles depending on their geographical origin. Principal Component Analysis showed a division between eastern and western Greece which might be owed to the existence of climatic fluctuations affecting the abiotic factors. This combined approach offers an important tool for stock identification thus assisting environmental risk assessments in evaluation of potential ecological effects and fostering research excellence in sustainable aquaculture management. 相似文献