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461.
Mannina L Cristinzio M Sobolev AP Ragni P Segre A 《Journal of agricultural and food chemistry》2004,52(26):7988-7996
A high-field NMR technique was used to analyze aqueous and organic extracts of truffles (Tuber aestivum vittadini) to characterize their chemical composition. Water-soluble metabolites belonging to different classes such as sugars, polyols, amino acids, and organic acids were almost completely assigned by means of one- and two-dimensional experiments (1H-1H COSY, TOCSY, 1H-13C HSQC, 1H-13C HMBC, and 1H-31P HMBC). The 1H spectral assignment of the cell membrane components such as lipids, sterols, and fatty acids extracted in organic solvents was also performed. 相似文献
462.
Gabriella Sonnante Angela R. Piergiovanni Quat N. Ng Pietro Perrino 《Genetic Resources and Crop Evolution》1996,43(2):157-165
Summary Isozyme variation in 25 accessions of wild and cultivated Vigna unguiculata, 49 accessions of seven wild species belonging to section Vigna, and 11 accessions of V. vexillata (subgenus Plectrotropis) was scored at 17 putative loci to assess genetic relationships within and among species. The wild species selected for this study are among those which carry important agronomical traits useful in cowpea (V. unguiculata) breeding programs. Allelic frequencies were calculated and Nei's genetic distances were obtained. Low levels of intraspecific variation were observed for V. heterophylla, V. luteola and V. racemosa, whereas the other species showed a higher polymorphism. Vigna unguiculata possessed intraspecific genetic distances comparable to those previously found by other authors. Most of the isozyme variation was apportioned among species. Although V. luteola and V. marina had an interspecific genetic distance resembling the range observed at intraspecific level, all the other species showed very high interspecific distances. Vigna unguiculata was relatively closer genetically to V. vexillata than to the species belonging to section Vigna.Abbreviations AUS
Australia
- BDI
Burundi
- BRA
Brazil
- BWA
Botswana
- CAF
Central African Republic
- GHA
Ghana
- CMR
Cameroon
- COG
Congo
- RI
Costa Rica
- EGY
Egypt
- ETE
Ethiopia
- GAB
Gabon
- GRC
Greece
- ITA
Italy
- KEN
Kenya
- MOZ
Mozambique
- NER
Niger
- NGA
Nigeria
- PAN
Panama
- RWA
Rwanda
- TCD
Chad
- TZA
Tanzania
- ZAF
South Africa
- ZAR
Zaire
- ZMB
Zambia 相似文献
463.
Genetic diversity and intra-specific phylogeny of Triticum turgidum L. subsp. dicoccon (Schrank) Thell. revealed by RFLPs and SSRs 总被引:2,自引:5,他引:2
Today, emmer wheat, T. turgidum subsp. dicoccon, widely grown in the past is a candidate crop for sustainable agriculture in Italy. As part of a research project aimed at the enhanced use of the hulled wheat germplasm, molecular characterization was carried out to understand the genetic structure of the crop and to identify accessions of interest. A collection of 194 accessions was analyzed with 15 microsatellite loci (SSRs), while only a sample of 38 accessions was tested with 19 RFLP probes. The marker loci were selected on the basis of their independent genomic distribution. Genetic distances and allelic frequencies were calculated for each marker class. The genetic relationships were visualized with dendrograms. RFLP loci were, on average, less polymorphic than SSRs. An average Dice's genetic distance of 0.22 for RFLPs vs 0.38 for SSRs was detected, while an expected average heterozygosity per locus of 0.23 for RFLPs vs 0.26 for SSRs was also estimated. With a least number of 10 loci per marker class it was possible to identify each genotype. The most diverse accessions had different geographic origins. Germplasms from Italy and Ethiopia appear to belong to a more primitive genepool, given that a group of accessions from these countries were genetically differentiated from a Russian-Iranian group. 相似文献
464.
Lo Cantore P Iacobellis NS De Marco A Capasso F Senatore F 《Journal of agricultural and food chemistry》2004,52(26):7862-7866
Essential oils were extracted from the fruits of Coriandrum sativum L. and Foeniculum vulgare Miller var. vulgare (Miller) and assayed in vitro for antibacterial activity to Escherichia coli and Bacillus megaterium, bacteria routinely used for comparison in the antimicrobial assays, and 27 phytopathogenic bacterial species and two mycopathogenic ones responsible for cultivated mushroom diseases. A significant antibacterial activity, as determined with the agar diffusion method, was shown by C. sativum essential oil whereas a much reduced effect was observed for F. vulgare var. vulgare oil. C. sativum and F. vulgare var. vulgare essential oils may be useful natural bactericides for the control of bacterial diseases of plants and for seed treatment, in particular, in organic agriculture. The significant antibacterial activity of essential oils to the bacterial pathogens of mushrooms appears promising. 相似文献
465.
466.
Lorenz RD Stiles BW Kirk RL Allison MD Del Marmo PP Iess L Lunine JI Ostro SJ Hensley S 《Science (New York, N.Y.)》2008,319(5870):1649-1651
Cassini radar observations of Saturn's moon Titan over several years show that its rotational period is changing and is different from its orbital period. The present-day rotation period difference from synchronous spin leads to a shift of approximately 0.36 degrees per year in apparent longitude and is consistent with seasonal exchange of angular momentum between the surface and Titan's dense superrotating atmosphere, but only if Titan's crust is decoupled from the core by an internal water ocean like that on Europa. 相似文献
467.
468.
469.
Ventura M Antonacci F Cardone MF Stanyon R D'Addabbo P Cellamare A Sprague LJ Eichler EE Archidiacono N Rocchi M 《Science (New York, N.Y.)》2007,316(5822):243-246
A systematic fluorescence in situ hybridization comparison of macaque and human synteny organization disclosed five additional macaque evolutionary new centromeres (ENCs) for a total of nine ENCs. To understand the dynamics of ENC formation and progression, we compared the ENC of macaque chromosome 4 with the human orthologous region, at 6q24.3, that conserves the ancestral genomic organization. A 250-kilobase segment was extensively duplicated around the macaque centromere. These duplications were strictly intrachromosomal. Our results suggest that novel centromeres may trigger only local duplication activity and that the absence of genes in the seeding region may have been important in ENC maintenance and progression. 相似文献
470.
Aiello A Fattorusso E Imperatore C Irace C Luciano P Menna M Santamaria R Vitalone R 《Marine drugs》2011,9(6):1157-1165
Chemical analysis of the Mediterranean ascidian Polyandrocarpa zorritensis (Van Name 1931) resulted in the isolation of a series of molecules including two monoindole alkaloids, 3-indolylglyoxylic acid (3) and its methyl ester (4), 4-hydroxy-3-methoxyphenylglyoxylic acid methyl ester (1) and a new alkaloid we named zorrimidazolone (2). The structure of the novel compound 2 has been elucidated by spectroscopic analysis and bioactivity of all compounds has been investigated. Zorrimidazolone (2) showed a modest cytotoxic activity against C6 rat glioma cell line. 相似文献