Contribution of dimethyl sulfide to the aroma of Syrah and Grenache Noir wines and estimation of its potential in grapes of these varieties     

Segurel MA  Razungles AJ  Riou C  Salles M  Baumes RL 《Journal of agricultural and food chemistry》2004,52(23):7084-7093

The contribution of dimethyl sulfide (DMS) to the aroma of Syrah and Grenache Noir wines from the Rhone Valley of France was investigated by sensory analysis, and its levels in these wines were measured. The potential DMS in the corresponding grapes and wines, susceptible to release during wine aging, was evaluated. Free DMS and potential DMS assessed by a heat-alkaline treatment were measured in grape juices and wines by SPME-GC-MS using methods previously reported and slightly modified. A relationship between potential DMS from grapes and the total DMS levels in wine was demonstrated. Furthermore, a linear regression between the ratio of free DMS levels to these total DMS levels in wine and time of storage was found. Free and potential DMS levels in grapes and wines depended on grape variety, vintage, and vine location. DMS imparted a noticeable and complex contribution to the aroma of the wines investigated, depending on the mode of sensory perception used, either before or after glass swirling. It significantly enhanced the fruity notes of the wines, and additional truffle and black olive notes.  相似文献   

Pathway of dephosphorylation of myo-inositol hexakisphosphate by phytases of legume seeds     

Greiner R  Larsson Alminger M  Carlsson NG  Muzquiz M  Burbano C  Cuadrado C  Pedrosa MM  Goyoaga C 《Journal of agricultural and food chemistry》2002,50(23):6865-6870

Using a combination of high-performance ion chromatography analysis and kinetic studies, the pathway of dephosphorylation of myo-inositol hexakisphosphate by the phytases purified from faba bean and lupine seeds, respectively, was established. The data demonstrate that the legume seed phytases under investigation dephosphorylate myo-inositol hexakisphosphate in a stereospecific way. The phytase from faba bean seeds and the phytase LP2 from lupine seeds degrade phytate by sequential removal of phosphate groups via D-Ins(1,2,3,5,6)P(5), D-Ins(1,2,5,6)P(4), D-Ins(1,2,6)P(3), and D-Ins(1,2)P(2) to finally Ins(2)P, whereas the phytases LP11 and LP12 from lupine seeds generate the final degradation product Ins(2)P via D-Ins(1,2,4,5,6)P(5), D-Ins(1,2,5,6)P(4), D-Ins(1,2,6)P(3), and D-Ins(1,2)P(2).  相似文献   

Physicochemical modifications of high-pressure-treated soybean protein isolates   总被引：7，自引：0，他引：7  

Puppo C  Chapleau N  Speroni F  De Lamballerie-Anton M  Michel F  Añón C  Anton M 《Journal of agricultural and food chemistry》2004,52(6):1564-1571

Changes induced by high pressure (HP) treatment (200-600 MPa) on soybean protein isolates (SPI) at pH 3 (SPI3) and pH 8 (SPI8) were analyzed. Changes in protein solubility, surface hydrophobicity (Ho), and free sulfhydryl content (SH(F)) were determined. Protein aggregation and denaturation and changes in secondary structure were also studied. An increase in protein Ho and aggregation, a reduction of free SH, and a partial unfolding of 7S and 11S fractions were observed in HP-treated SPI8. Changes in secondary structure were also detected, which led to a more disordered structure. HP-treated SPI3 was partially denatured and presented insoluble aggregates. A major molecular unfolding, a decrease of thermal stability, and an increase of protein solubility and Ho were also detected. At 400 and 600 MPa, a decrease of the SH(F) and a total denaturation were observed.  相似文献   

A method for testing drought tolerance in <Emphasis Type="Italic">Fragaria</Emphasis> based on fast screening for water deficit response and use of associated AFLP and EST candidate gene markers     

Farzaneh?RazaviEmail author  Ellen?De?Keyser  Jan?De?Riek  Marie?Christine?Van?Labeke 《Euphytica》2011,180(3):385-409

Drought stress is one of the most important environmental factors that limit plant growth and development, thus reducing yield. The objective of the present research was to correlate the genetic structure of different Fragaria genotypes, as assessed by Expressed Sequence Tag (EST) and Amplified Fragment Length Polymorphism (AFLP) markers, and plant responses to drought stress. Firstly, physiological parameters related to the plant response to drought stress such as leaf relative water content (RWC) and water losing rate (WLR) were measured. WLR and RWC were compared for 20 cultivars of the octaploid Fragaria × ananassa, two ecotypes of the diploid species F. vesca and one octaploid species F. chiloensis. These parameters could discriminate genotypes showing a contrasting response to water stress. Secondly, AFLP and ESTs were compared in terms of their information content and efficiency in the study of genetic diversity and relationships among these 23 Fragaria genotypes. To evaluate the genetic basis for the observed variation in the measured physiological parameter, the effect of specific AFLP/EST loci on WLR and RWC for the different Fragaria genotypes was quantified by Kruskal–Wallis analysis. By Mantel testing, the hierarchical clustering of the Fragaria genotypes based on associated EST or AFLP markers was compared to the observed eco-physiological relevant grouping. A better discriminating capacity for associated markers was noted, enabling a functional marker selection approach to screen the strawberry gene pool for drought tolerance. Correlation of EST markers to leaf RWC and WLR enforces them as potential candidate genes in control of plant responses to drought stress in Fragaria sp.  相似文献   

Comparison of manure compost and mineral fertilizer for hybrid poplar plantation establishment on boreal heavy clay soils     

Marie Larcheveque  Annie Desrochers  Guy R. Larocque 《Annals of Forest Science》2011,68(4):849-860

• Introduction   

Clay soils are typically rich in nutrients but are often compact and hard during summer increasing planting shock by limiting root development. Recycling farm manure in hybrid poplar plantations may offer additional benefits to mineral fertilizer as organic amendment can create better conditions for the early development of roots in addition to nutrient release.  相似文献   

Physiological responses of black spruce layers and planted seedlings to nutrient addition     

Paquin R  Margolis HA  Doucet R  Coyea MR 《Tree physiology》2000,20(4):229-237

We investigated effects of nutrient addition on several physiological characteristics of 60-cm-tall black spruce (Picea mariana Mill. B.S.P.) layers (i.e., rooted branches of overstory trees) and 20-cm-tall planted seedlings on a clear-cut, N-limited boreal site. After two growing seasons, current-year and one-year-old needles of fertilized trees (layers and seedlings combined) had higher net photosynthetic rates (A(n)) and maximum capacity of Rubisco for CO(2) fixation (V(max)) than unfertilized trees. One-year-old needles of fertilized trees had higher stomatal conductance (g(s)), higher water-use efficiency, and lower intercellular to ambient CO(2) ratio than unfertilized trees. Additionally, fertilized trees had higher predawn and midday shoot water potentials than unfertilized trees. Stomatal conductance of 1-year-old needles was 23% higher in seedlings than in layers, but there were no significant differences in g(s) of current-year needles between the regeneration types. For both needle age-classes, A(n) and V(max) of layers were 25 and 40% higher, respectively, than the corresponding values for seedlings. The higher values of A(n), V(max) and foliar N concentration of layers compared with seedlings after two growing seasons may be associated with the larger root systems of the layers compared with the transplanted seedlings.  相似文献   

Reverse engineering of biological complexity     

Csete ME  Doyle JC 《Science (New York, N.Y.)》2002,295(5560):1664-1669

Advanced technologies and biology have extremely different physical implementations, but they are far more alike in systems-level organization than is widely appreciated. Convergent evolution in both domains produces modular architectures that are composed of elaborate hierarchies of protocols and layers of feedback regulation, are driven by demand for robustness to uncertain environments, and use often imprecise components. This complexity may be largely hidden in idealized laboratory settings and in normal operation, becoming conspicuous only when contributing to rare cascading failures. These puzzling and paradoxical features are neither accidental nor artificial, but derive from a deep and necessary interplay between complexity and robustness, modularity, feedback, and fragility. This review describes insights from engineering theory and practice that can shed some light on biological complexity.  相似文献   

Single-molecule DNA sequencing of a viral genome   总被引：4，自引：0，他引：4  

Harris TD  Buzby PR  Babcock H  Beer E  Bowers J  Braslavsky I  Causey M  Colonell J  Dimeo J  Efcavitch JW  Giladi E  Gill J  Healy J  Jarosz M  Lapen D  Moulton K  Quake SR  Steinmann K  Thayer E  Tyurina A  Ward R  Weiss H  Xie Z 《Science (New York, N.Y.)》2008,320(5872):106-109

The full promise of human genomics will be realized only when the genomes of thousands of individuals can be sequenced for comparative analysis. A reference sequence enables the use of short read length. We report an amplification-free method for determining the nucleotide sequence of more than 280,000 individual DNA molecules simultaneously. A DNA polymerase adds labeled nucleotides to surface-immobilized primer-template duplexes in stepwise fashion, and the asynchronous growth of individual DNA molecules was monitored by fluorescence imaging. Read lengths of >25 bases and equivalent phred software program quality scores approaching 30 were achieved. We used this method to sequence the M13 virus to an average depth of >150x and with 100% coverage; thus, we resequenced the M13 genome with high-sensitivity mutation detection. This demonstrates a strategy for high-throughput low-cost resequencing.  相似文献   

Growth of prochlorococcus, a photosynthetic prokaryote, in the equatorial pacific ocean     

Vaulot D  Marie D  Olson RJ  Chisholm SW 《Science (New York, N.Y.)》1995,268(5216):1480-1482

The cell cycle of Prochlorococcus, a prokaryote that accounts for a sizable fraction of the photosynthetic biomass in the eastern equatorial Pacific, progressed in phase with the daily light cycle. DNA replication occurred in the afternoon and cell division occurred at night. Growth rates were maximal (about one doubling per day) at 30 meters and decreased toward the surface and the bottom of the ocean. Estimated Prochlorococcus production varied between 174 and 498 milligrams of carbon per square meter per day and accounted for 5 to 19 percent of total gross primary production at the equator. Because Prochlorococcus multiplies close to its maximum possible rate, it is probably not severely nutrient-limited in this region of the oceans.  相似文献   

Role of formins in actin assembly: nucleation and barbed-end association   总被引：2，自引：0，他引：2  

Pruyne D  Evangelista M  Yang C  Bi E  Zigmond S  Bretscher A  Boone C 《Science (New York, N.Y.)》2002,297(5581):612-615

Nucleation of branched actin filaments by the Arp2/3 complex is a conserved process in eukaryotic cells, yet the source of unbranched actin filaments has remained obscure. In yeast, formins stimulate assembly of actin cables independently of Arp2/3. Here, the conserved core of formin homology domains 1 and 2 of Bni1p (Bni1pFH1FH2) was found to nucleate unbranched actin filaments in vitro. Bni1pFH2 provided the minimal region sufficient for nucleation. Unique among actin nucleators, Bni1pFH1FH2 remained associated with the growing barbed ends of filaments. This combination of properties suggests a direct role for formins in regulating nucleation and polarization of unbranched filamentous actin structures.  相似文献