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Sugarcane bagasse is a lignocellulosic agro-industrial waste, which is usually burned in the sugar and bio-ethanol mills to produce heat and electricity. This work presents the kinetic study of the carbohydrates extracted from the mild hot water pretreatment of sugarcane bagasse, to explain the variation of hemicellulosic carbohydrates during the treatment. This could allow the selection of optimum conditions to obtain the desired products in spent liquors, as high concentration of xylans and low concentrations of fermentation inhibitors. Sugarcane bagasse was hydrothermally treated under isothermal conditions at 160, 170, and 180 °C, using a liquid to solid ratio of 14:1. Glucans, xylans, arabans, xylose, glucose, arabinose, acetic acid, formic acid, HMF and furfural were first identified in the spent liquor. A kinetic model was applied, considering the direct extraction of xylose and oligomers from the solid, xylose production from the oligomers, and furfural generation from xylose. It was supposed that the reaction rate constants have first-order kinetics. The fractionation by hydrothermal treatment has proven to be effective for hemicelluloses removal. Most glucans were retained in the solid, and a partial delignification (at 180 °C, 9.8% and 36.3% of the initial lignin at 20 and 240 min, respectively) was achieved. The maximum concentration of xylans in spent liquors with the low furfural content (0.5% on oven dry bagasse) was achieved at 180 °C and 20 min of treatment (17.6% on oven dry bagasse, about 74% of the initial amount). An activation energy of 128.8 kJ mol −1 has been obtained for the fast hydrolysis of xylans from sugar cane bagasse. The maximal concentration of xylans + xylose in liquors was obtained with a P -factor of 800. [ABSTRACT FROM AUTHOR]

The physicochemical, shear flow behaviour and emulsifying properties of gum exudates from Acacia cochliacantha and Acacia farnesiana were analysed and compared to those for Acacia senegal gum. Evaluation of physicochemical properties showed that A . farnesiana and A . senegal gums displayed levorotatory activity, relatively high carbohydrate/protein ratio and high content of dietary fibre. Similarly, A . farnesiana and A . senegal gums formed stable oil-in-water emulsions with smaller droplet sizes and coalescence rates in the order of 10 −8 , meaning for very stable disperse systems. Otherwise, A . cochliacantha gum was the only with dextrorotatory activity, high content of protein and arabinogalactan-proteins (AGPs), but low carbohydrate fraction; nevertheless, despite the possible advantages of high protein content associated with emulsifying properties, this polysaccharide showed lesser stability on emulsions. These results indicate that there is correlation between emulsion stability and an adequate carbohydrate/protein balance in the gums; additionally of the AGPs presence. Thus, A . farnesiana gum may be considered for oil-in-water emulsion stabilization and sources of soluble dietary fibre due to their relatively high polysaccharide fraction. [ABSTRACT FROM AUTHOR]

Monoclonal antibodies that recognize plant cell wall glycans are used for high-resolution imaging, providing important information about the structure and function of cell wall polysaccharides. To characterize the binding epitopes of these powerful molecular probes a library of eleven plant arabinoxylan oligosaccharides was produced by automated solid-phase synthesis. Modular assembly of oligoarabinoxylans from few building blocks was enabled by adding (2-naphthyl)methyl (Nap) to the toolbox of orthogonal protecting groups for solid-phase synthesis. Conjugation-ready oligosaccharides were obtained and the binding specificities of xylan-directed antibodies were determined on microarrays. [ABSTRACT FROM AUTHOR]

This paper reports on the analysis of carbohydrate components in bread crusts, made of seven controlled mixtures of buckwheat and wheat flour. These were mono-, disaccharides and some heterocyclic compounds derivatized into their corresponding trimethylsilyl ethers and analysed by a gas chromatography-mass spectrometry system. Selected ion monitoring (SIM) chromatograms with m/z signals of 73, 204 and 217 were selected from total ion current (TIC) chromatograms, as the selected ions are known to be characteristic for silylated carbohydrates. Programmes AMDIS (Version 2.66) and NIST (MS Search Version 2.0), and NIST08 library (National Institute of Standards and Technology, Gaithersburg, Maryland, USA) were used to confirm the presence of carbohydrates. The aim was to evaluate applicability of multivariate analysis of the stated components to determination of the content of buckwheat flour in bread, made of a mixture of buckwheat and wheat flours. It was sufficient to use the principal component analysis and a dendrogram to clearly present the proportion of buckwheat flour in bread. [ABSTRACT FROM AUTHOR]

Separating soil respiration (Rs) into heterotrophic (RH) and autotrophic (RA) components often relies on root-severing techniques with the presumption that RAwill approach zero as root nonstructural carbohydrate (NSC) supply diminishes. To test this assumption, we evaluated changes in carbon dioxide (CO2) flux rates and NSC concentrations after severingPinus taedaL. roots using laboratory and field approaches. After an 86-day laboratory incubation, soluble, insoluble, and total NSCs decreased by 60, 29, and 43 percent, respectively. RSand RAdeclined asymptotically, reduced by 86 and 95 percent, respectively. Correlation coefficients between RAand soluble, insoluble, and total NSCs were 0.90, 0.69, and 0.93, respectively. In a field study, respiration stabilized after 40 days with mean rates in root-severed areas 21. ± 0.5 percent less than in undisturbed areas. This relationship between total NSCs and RS, and the steady decline in RSand RAover time, validates the use of field-installed root-severing cores to measure RH. [ABSTRACT FROM AUTHOR]

Oriental hybrid lily "Arabian Red" mother scales were stored in moist cocopeat and perlite (1:1) for 3 or 5 months at 25 °C. The numbers of scale bulblets per mother scale were nearly identical in two durations. Increasing storage duration promoted the growth of roots (number and length) and No. scales per scale bulblets. And, diameters of scale bulblets were more in longer storage duration (5 months) than 3 months. Therefore, storage duration affects size, no quantity of scale bulblets in "Arabian Red" lily. This can cause with giving opportunity to scale bulblet for more consuming the reserves of parent scale and extending the root growth, then produce greater bulblet. The results show that scale bulblets had more sucrose and glucose in 5 months, the content of fructose did not change in development process nevertheless, it seems, that has not any effect on the sprouting bulblets. [ABSTRACT FROM AUTHOR]

Despite extensive research on the seasonal dynamics of non-structural carbohydrate (NSC) and nitrogen (N) concentrations, the size and relative contributions of NSC and N pools across different tree organs are not well understood. We have measured the changes in NSC and N concentrations in leaves, branches, stems and all root branch orders at monthly intervals in control and girdled trees of larch ( Larix gmelinii) and ash ( Fraxinus mandshurica). The biomass of each plant compartment was also determined to calculate the size of the NSC and N pools. In both species, 13-37 % of the NSC and N pools were mobilized at the beginning of the growing season. Among the mobilized pools, stems and non-absorptive roots (branch orders 4-9) acted as the largest NSC sources in larch and ash, respectively, while branches served as the largest N source in both species. After stem girdling, 22 and 50 % of the root NSC stores in larch and ash, respectively, were mobilized to maintain root activities during the growing season. Tree mortality was observed 1 year after girdling, at which time there was still an abundant NSC pool in the roots. We conclude that (1) different storage organs differ in their contribution to new tissue growth at the beginning of the growing season and that those storage organs holding higher fractions of the NSC or N pool are not necessarily those which mobilize more NSC or N; (2) tree growth may not be limited by carbon (C) availability; (3) C storage in non-absorptive roots plays an important role in maintaining tree survival after the termination of photosynthate flow from aboveground sources. [ABSTRACT FROM AUTHOR]

By comparison with plant-microbe interaction, little is known about the interaction of parasitic plants with their hosts. Plants of the genus Cuscuta belong to the family of Cuscutaceae and comprise about 200 species, all of which live as stem holoparasites on other plants. Cuscuta spp. possess no roots nor fully expanded leaves and the vegetative portion appears to be a stem only. The parasite winds around plants and penetrates the host stems via haustoria, forming direct connections to the vascular bundles of their hosts to withdraw water, carbohydrates, and other solutes. Besides susceptible hosts, a few plants exist that exhibit an active resistance against infestation by Cuscuta spp. For example, cultivated tomato (Solanum lycopersicum) fends off Cuscuta reflexa by means of a hypersensitive-type response occurring in the early penetration phase. This report on the plant-plant dialog between Cuscuta spp. and its host plants focuses on the incompatible interaction of C. reflexa with tomato. [ABSTRACT FROM AUTHOR]

The present study was designed to identify the ability of the leaf extract from Syzygium malaccense (L.) Merr. & L.M. Perry to scavenge DPPH, ABTS and NO radicals; to inhibit the carbohydrate-hydrolyzing enzymes α-glucosidase and α-amylase; and, eventually, to identify and quantify its bioactive compound(s). The S. malaccense leaf extract was a far better scavenger of DPPH and ABTS than of nitric oxide. It also inhibited α-glucosidase more significantly than the positive control, acarbose, but was a poor α-amylase inhibitor. Myricitrin was identified by using high-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LCMS) techniques as the major bioactive compound present in the extract. The percent yield of myricetin derivatives in the extract was determined to be 3.3 ± 0.05%. The presence of the potent antioxidant and antihyperglycemic agent myricitrin in the S. malaccense leaf extract indicates the potential use of the extract in the management of diabetes mellitus and its related complications. [ABSTRACT FROM AUTHOR]

Making full use of lipid and carbohydrate in microalgae for joint production of biodiesel and bioethanol may create a potential way to cut the high cost of single biofuel production from microalgae. Compared with conventional unicellular oleaginous microalgae, filamentous microalgae Tribonema sp. is richer in lipid and carbohydrate contents and lower protein content, thus, this study explores the suitability of Tribonema sp. as a substrate for joint production of biodiesel and bioethanol. Acid hydrolysis is the key step to saccharify wall cell into fermentable sugar and release lipid. Microalgae biomass (50 g/L) was acid (3% H 2 SO 4 ) hydrolyzed at 121 °C for 45 min to reach the maximum hydrolysis efficiency (81.48%). Subsequently, the lipid separated with hexane–ethanol from the hydrolysate was converted into microalgae biodiesel and the conversion rate was 98.47%. With yeast Saccharomyces cerevisiae , the maximum ethanol yield of 56.1% was reached from 14.5 g/L glucose in hydrolysate. [ABSTRACT FROM AUTHOR]

A proximate analysis study of local rice bran and brown rice disclosed a distinguish level of chemical compositions. Lipid, carbohydrate and ash occupy in rice bran, while fibre is a predominant component in brown rice. Both perceptible anti-cholesterol substrates were grown with locally isolated Fusarium pseudocircinatum IBRL B3-4 to obtain the best lovastatin activity via dichloromethane extraction. Evaluation of lovastatin production at different substrate thickness ranges of 0.25 to 1.5 cm in a static tray system (20x20x6 cm3) exposed the highest production at 0.5 cm level (1135.0±6.7 pg/g dry solid of lovastatin). Meanwhile, effects of physical parameters investigation interpreted that the original substrate size, 60% (v/w) moisture content and ambient local temperature of 30±2°C as the most suitable conditions to generate lovastatin at the utmost level. Meanwhile, the maximum production was synthesized at day 12th (twelfth) under solid substrate fermentation system. A significant activity increment was revealed after 60 % (v/v) moisture content had been applied into tray system. In more specific, it boosted up to 2271.7±14.4 pg/g dry solid of lovastatin. [ABSTRACT FROM AUTHOR]

It is well established that a period of exposure to low temperature is required in order for temperate plants to achieve maximum freezing tolerance. During the cold acclimation process a large number of biophysical, biochemical and molecular changes occur that enable the plant to survive at below freezing temperatures. These include the alteration of carbohydrate and protein accumulation profiles, resulting large quantities of soluble sugars and cold induced stress proteins (dehydrins) thought to function in a cryoprotective role. When fully cold acclimated plants are exposed to warm temperatures (de-acclimation) a rapid turnover of these carbohydrates and proteins occurs, resulting in a plant that no longer possesses an elevated level of freezing tolerance. In certain species, re-exposure to cold acclimating temperatures (re-acclimation) results in re-accumulation of carbohydrates and proteins with a synergistic impact on freezing tolerance. In canola (Brassica napus L.), a full recovery of freezing tolerance is observed upon re-acclimation in both spring and winter cultivars. In contrast, the re-acclimation of winter wheat (Triticum aestivum L.) results in only a 39% recovery of freezing tolerance. Upon further analysis it was revealed that wheat does not accumulate carbohydrates during the re-acclimation period. While certain dehydrins also accumulate during re-acclimation, there is no clear relationship with freezing tolerance and we suggest it is the interaction of these proteins with soluble carbohydrates that is responsible for the development of freezing tolerance during re-acclimation. The role of vernalization in these processes is also discussed. [ABSTRACT FROM AUTHOR]

The removal of total carbohydrates and phenolics from the hull of a new barley variety BT 584 using solid-liquid batch and aqueous pressurized fluid (ethanol or ionic liquid) extractions were evaluated. Using pressurized fluids, temperature was the most significant variable for the extraction of biocompounds from barley hull. The highest phenolics extraction (189.1 ± 3.1 mg/g hull) was obtained using pressurized aqueous ionic liquid while the highest carbohydrates extraction (450.3 ± 7.8 mg/g hull) was obtained using pressurized aqueous ethanol. The predicted solubility of ferulic acid and glucose in water, ionic liquid or carbonic acid, and the acid dissociation constant of the compounds studied allowed proposing an extraction mechanism based on biomass interaction with ionic species formed during pressurized fluid extraction. The anionic species facilitated removal of phenolics while the interaction of cationic/anionic species facilitated removal of carbohydrates from barley hull biomass. [ABSTRACT FROM AUTHOR]

A multi-scale length and multi-feature exploration of woody hemp core (WHC) using 6 internodes (INs) along the height of the stem was conducted, and then, the putative IN location dependence of composites made of the WHC was evaluated. At the nanoscale level, we observed a good inter-stem reproducibility of cell wall properties using nanoindentation tests as well as moderate increases in the values of the indentation modulus and hardness from the bottom to top of the stem (8.5-10.5 GPa and 200-350 MPa, respectively). Biochemical analysis revealed that the lignin content decreased significantly (by approximately 1.5% in terms of the WHC dry matter mass) from the bottom to the top of the stem. Individual stem carbohydrate trends differed when compared with the average values of a group of 10 stems. Along the height of the stem, no variation in the total carbohydrate content was observed in the average of 10 stems, but the monosaccharide details exhibited mixed behaviors. The arabinose and galactose contents increased from the bottom to top of the stem and were strongly correlated with structural properties, i.e., relative density, Young's modulus, and toughness, as well as with lignin content. At the microscale level, from the bottom to top IN of the stems, the relative density of the WHC exhibits a 2.8-fold reduction. At the mesoscale level, bending tests showed huge variations between IN locations; Young's modulus, strength at break and fracture energy exhibit 4, 2 and 5-fold variations, respectively. Despite all of these structural and biochemical variations along the WHC stem, composites made of particles from the bottom, median, or top WHC locations did not show any variations in Young's modulus, stress or elongation at break. The influence of the extrusion and injection process steps of making wood-plastic composites is discussed in connection with the preservation of the pre-processing intrinsic potential of the raw fiber materials. [ABSTRACT FROM AUTHOR]

Abstract: This paper is to explore the biogas production potential of wetland aquatic biomass plants. 7 species of wetland aquatic biomass plants are used in the study, which include 4 plants with more fiber carbohydrate, Acorus calamus Linn, Typha orientalis Presl, Pontederia cordata and Canna indica, and 3 plants with more starch carbohydrate, Colocasia tonoimo Nakai, Thalia dealbata and Hydrocotyle vulgaris. In the experiment, these plants were treated by anaerobic fermentation in batch mode at 37 °C. The results show that the anaerobic biogas production potential (ABP, mL·g−1 VS) of aquatic biomass plants is different for different components content (%TS). The correlation between ABP and hemicellulose content is significant and negative (R = −0.784, 0.01 < p < 0.05), and the correlation between ABP and starch carbohydrate content is significant and positive (R = 0.767, 0.01 < p < 0.05). The multiple stepwise regression equation with cross variable can roughly meet the statistical model to reflect the coeffect of hemicellulose, cellulose, starch carbohydrate and lignin on ABP of aquatic biomass plants, y = 238.62 + 2.60x 1 + 28.55x 2−2.08x 2 x 3 + 12.67x 3, (Adj-R 2 = 0.962, p(intercept) = 0.034, p(x 1) = 0.101, p(x 2) = 0.036, p(x 2 x 3) = 0.066, p(x 3) = 0.031, p = 0.025, SD = 9.95), y represents ABP (mL g−1 VS), x 1, x 2 and x 3 represents the cellulose, lignin and starch carbohydrate content (%TS) respectively. [Copyright &y& Elsevier]

Brachypodium distachyon is a widely recognized model plant belonging to subfamily Pooideae with a sequenced genome. To gain a better understanding of the male reproductive development in B. distachyon we examined pollen morphology and cytochemical changes of microspore cytoplasm from pollen mother cell stage to mature pollen using light, fluorescent and scanning electron microscopy. Our results show that B. distachyon exhibits a typical monocot-type pollen ontogeny. Meiosis in the pollen mother cells is accomplished by successive cytokinesis generating isobilateral tetrads. Cytochemical examination indicated that microspore cytoplasm contains variable amounts of insoluble carbohydrates and proteins at different developmental stages. Deposition of starch in the cytoplasm of microspores starts at the bicellular stage and continues till the mature pollen stage. The formation of the exine wall progresses by the deposition of sporopollenin from the tapetum layer of the anther. The mature pollen is trinucleate, spheroidal in shape and possesses a single pore with an annulus and operculum. The exine pattern is smooth and of granular type. [ABSTRACT FROM AUTHOR]

In the present work the in vitro prebiotic activity of inulin-rich carbohydrates using Lactobacillus paracasei as probiotic microorganism was determined. With this purpose, inulin-rich carbohydrates samples from Jerusalem artichoke tubers stored at 4-5°C during different times along an overall period of 8months were extracted. Extraction yield, inulin content and average polymerization degree of inulin-rich carbohydrates samples were also determined. For all samples, extraction yield and inulin content decreased with storage time. In particular, inulin content exhibited values within the range of commercial food grade inulin (≥85%). Average polymerization degree values decreased with storage time ranging from 12.1 to 8.3. The in vitro prebiotic activity of inulin-rich carbohydrates samples was assessed using a prebiotic activity score which considered the growing ratio relative to glucose of L. paracasei as well as of the enteric bacteria Escherichia coli when such carbohydrates were used as C source. Inulin-rich carbohydrates extracted from tubers cold-stored during 4months showed the highest prebiotic activity score, even higher than the corresponding to a commercial food grade inulin, indicating that this sample should be used as a prebiotic food ingredient, representing a potential alternative to the available commercial inulin obtained from chicory roots. [ABSTRACT FROM AUTHOR]

The dynamics of non-structural carbohydrates (NSC) in various fractions of cotton boll might have significant impact on within-boll lint and seed yields. The objective of this research was to determine how NSC in the three fractions of cotton boll (the fiber, the seed, and the burfluctuated at various stages of development and assess whether there was any association between carbohydrate profiles and boll characters. Five upland cotton genotypes differing in boll size and its components were examined in 2011 and 2012. Boll samples were harvested at 10, 17, 24, 31, 38, 45, and 52 days post anthesis (DPA) and analyzed for glucose, fructose, sucrose and starch. The starch concentration in those fractions from all genotypes was characterized by a declining trend with a faster decrease during the first 24 DPA than during later stages of boll development in both years. The sucrose concentration in embryos increased up to 24 DPA and then declined down to a minimum at 38 DPA corresponding the beginning of embryo desiccation. Thereafter, the sucrose concentration increased linearly, to form a second peak observed at 52 DPA. No difference between two years was found for the kinetics of sucrose concentration in embryos. The sucrose, glucose and fructose concentrations in fibers presented as single-peak curves during fiber development with the maxima occurring at either 17 or 24 DPA, corresponding to the transition phase from primary to secondary wall formation or to the beginning of massive secondary cell wall formation. Boll characters (boll size, lint percentage, and lint mass per boll) were more related to the starch and sucrose changes in embryos than in fibers. Sucrose might withdraw from either seeds or fibers to burs by maturity. [ABSTRACT FROM AUTHOR]

The pumpkin phloem lectin (PP2) is an RNA-binding, defense-related, chitooligosaccharide-specific, homodimeric lectin of Mr 48 kDa expressed at high concentrations in the sieve elements and companion cells of pumpkin (Cucurbita maxima). In the present study, PP2 was expressed in the methylotrophic yeast Pichia pastoris with the Saccharomyces α-factor sequence to direct the recombinant protein into the secretory pathway as a prerequisite for unimpaired folding and posttranslational glycosylation of recombinant PP2. Previous computational modeling and ligand docking studies predicted a putative chitooligosaccharide-binding site on the PP2 surface, which was divided into three subsites, with two amino acid residues in each subsite identified as possible candidates for interaction with chitooligosaccharides (CHOs). In this work, mutational analysis and hemagglutination assays were employed to verify the role of the predicted residues in the carbohydrate binding activity of the protein. The results obtained revealed that mutation of Ser-104 to Ala (S104A) at subsite-2 resulted in about 90% loss of agglutination activity of the protein, indicating that Ser-104 is crucial for the binding of CHOs to PP2. Also, L100A (at subsite-1) and K200A (at subsite-3) independently decreased the lectin activity by about 40%, indicating that these two residues also contribute significantly to sugar binding by PP2. Together, these findings confirm that all the three subsites contribute to varying degrees toward PP2-carbohydrate interaction, and confirm the validity of the computational model, as proposed earlier. [ABSTRACT FROM AUTHOR]

Light and temperature are the most important environmental conditions that impact the growth and quality of grafted vines. In this research, the most suitable light and temperature conditions were tested to determine the best environment for grafted vines grown in pots. This study was conducted to determine the influence of different growth conditions, such as open field, shaded greenhouse and unshaded greenhouse, on grafted vine growth and quality. The length and diameter of shoot, trunk diameter, mean and total leaf area, total soluble sugars, starch and total carbohydrate contents of 'Narince' and 'Trakya Ilkeren' vines, grafted on 5C rootstock, were investigated in this study. Shaded conditions yielded significantly higher shoot lengths, mean and total leaf areas than other conditions (p<0.05). Among the growth parameters, the highest correlation (r = 0. 819) was observed between shoot length and plant total leaf area (p<0.01). The total soluble sugars, starch and total carbohydrates content of vines under shaded and unshaded conditions were higher (p<0.05) than those under open field conditions. Grafted vines had the highest carbohydrate content in unshaded conditions. Under different light intensity, temperature and relative humidity conditions studied, the better results were obtained in the case of unshaded conditions. [ABSTRACT FROM AUTHOR]

Fourier Transform Mid-Infrared Spectroscopy (FT-MIR) combined with multivariate data analysis have been applied for the discrimination of 15 different Romanian wines (white, rosé and red wines), obtained from different origin-denominated cultivars. Principal component analysis and hierarchical cluster analysis was performed using different regions of FT-MIR spectra for all wines. The general fingerprint of wines was splitted in four characteristic regions, corresponding to phenolic derivatives, carbohydrates, amino acids and organic acids, which confer the wines quality and authenticity. By qualitative and quantitative evaluation of each component category, it was possible to discriminate each wine category, from red, to rosé and white colours, to dry, half-dry and half-sweet flavours. The multivariate data analysis based on absorption peaks from FT-MIR spectra demonstrated a very good, significant clustering of samples, based on the four main components: phenolics, carbohydrates, amino acids and organic acids. Therefore, the ATR-FT-MIR analysis proved to be a very fast, cheap and efficient tool to evaluate the quality and authenticity of wines, and to discriminate each wine category, based on their colour and sweetness, as consequence of their biological (cultivar) specificity. [ABSTRACT FROM AUTHOR]

Abstract: Four newly developed huless barley cultivars with altered carbohydrate traits were developed at the Crop Development Centre (CDC), University of Saskatchewan which varied for amylose (1–40% DM), and β-glucan (5–10% DM) content. The four hulless barley cultivars include zero-amylose waxy, CDC Fibar; 5%-amylose waxy, CDC Rattan; normal-amylose, CDC McGwire and high-amylose, HB08302. CDC Copeland was also included as a hulled barley control. Our previous study revealed the altered carbohydrate traits in barley affected nutrition availability and rumen degradation kinetics. These biological differences may be caused by differences in their molecular structure features. The objectives of this study were to (1) reveal molecular structure features in the four hulless barley cultivars with altered carbohydrate traits, and (2) quantify the molecular structural features in relation to rumen degradation kinetics, intestinal nutrient digestion and predicted protein supply to dairy cattle. Conventional Molecular Infrared-vibration Spectroscopy was applied to detect biochemical characteristics of functional group bands including protein, non-starch carbohydrate (β-glucan and cellulosic compounds) and total carbohydrate. Spectral data were further analyzed using univariate analysis of recording absorption peak parameters (baseline, region, relative height and area) and also multivariate analysis with agglomerative hierarchical cluster analysis and principal components analysis. Although correlation results showed weak correlation (P < 0.05) between identified functional group bands and ruminal degradation kinetics and estimated protein supply from both models, molecular structure differences of hulless barley cultivars can still be detected by the Molecular Infrared-vibration Spectroscopy technique and potential truly protein supply (MP) was significantly affected (P < 0.05) by protein molecular structure characteristics in hulless barley cultivars. [Copyright &y& Elsevier]

Changes in protein, lipid, and carbohydrate content, and the weight loss of soybean seeds caused by the feeding of 6- to 7-d-old unmated male adults of the pentatomids Peizodorous hybneri (Gmelin) and Halymorpha halys (Stål), and an alydid, Riptortus pedestris (F.), were examined in the laboratory. Our goals were to determine which species had the greatest capacity to damage soybean seed and to measure the effect of that damage on the nutritional composition of soybean seed. Individuals of the three species were provided with a preweighed dry soybean seed and allowed to feed for 0, 4, 8, 12, 16, 20, and 24 d, after which the remaining seed was analyzed for any change in weight, protein, lipid, and carbohydrate concentration. Lipids, carbohydrates, and seed weights were reduced by bug feeding, and the reduction was directly proportional to feeding duration. H. halys was found to be the most voracious feeder, reducing soybean seed weight by 42% after 24 d of feeding. There was a significant interaction between species and feeding duration for changes in nutritional components. Seeds fed on by H. halys had the highest incremental increase in protein content (13%) after 24 d of feeding, followed by those fed on by R. pedestris and P. hybneri. However, carbohydrates and lipid content of the soybean seeds fed by the tested insect species were found to decrease significantly. Soybean pods at mature stages remain in the field for a long period, and findings of our study suggest that longer exposure of the mature soybean pods to these pest species in the field may lead to low-quality seeds and lower yields, and may even affect the germination potential of the seeds. [ABSTRACT FROM AUTHOR]

Light pruning and deficit irrigation regimes are practices which are widely used in high yielding commercial vineyards in the warm climate regions of Australia. Little information is available on their impacts on carbohydrate dynamics in vegetative organs within and between seasons, and on the resulting plant capacity to maintain productivity and ripen fruits. This study was conducted to address this gap in knowledge over five vintages on Vitis vinifera L. cv. Cabernet Franc, Shiraz, and Cabernet Sauvignon in the Sunraysia region of Victoria, Australia. Lighter pruning did not change the total carbohydrates concentration and composition in wood and roots within seasons in Cabernet Franc and Shiraz. However, the total carbohydrate pool (starch and soluble sugars) at the end of dormancy increased under lighter pruning, due to higher vine size, associated with retention and growth of old-wood (trunk and cordons). Water deficit negatively impacted trunk and leaf starch concentrations, over the day and within seasons in Cabernet Sauvignon. Soluble sugars concentrations in these tissues tended to be higher under limited water supply, possibly due to higher sugar mobilization as photosynthesis decreased. Trunk carbohydrate concentrations markedly varied within and between seasons, highlighting the importance of interactive factors such as crop load and climate on carbon status. The period between fruit-set and véraison was shown to be critical for its impact on the balance between carbon accretion and depletion, especially under water deficit. The lower leaf and trunk starch concentration under water deficit resulted in a decrease of yield components at harvest, while similar yields were reached for all pruning systems. The sugar allocated to berries at harvest remained remarkably stable for all practices and seasons, irrespective of vine yield and carbohydrate status in vegetative organs in Shiraz and Cabernet Sauvignon. [ABSTRACT FROM AUTHOR]

Understanding the role of branch architecture in carbon production and allocation is essential to gain more insight into the complex process of assimilate partitioning in fruit trees. This mini review reports on the current knowledge of the role of branch architecture in carbohydrate production and partitioning in apple. The first-order carrier branch of apple illustrates the complexity of branch structure emerging from bud activity events and encountered in many fruit trees. Branch architecture influences carbon production by determining leaf exposure to light and by affecting leaf internal characteristics related to leaf photosynthetic capacity. The dynamics of assimilate partitioning between branch organs depends on the stage of development of sources and sinks. The sink strength of various branch organs and their relative positioning on the branch also affect partitioning. Vascular connections between branch organs determine major pathways for branch assimilate transport. We propose directions for employing a modelling approach to further elucidate the role of branch architecture on assimilate partitioning. [ABSTRACT FROM AUTHOR]

Highlights: [•] Sweet orange scions grafted on Rangpur and Swingle rootstocks under water deficit. [•] The growth of plants on Rangpur lime was not affected by water shortage. [•] Plants on Rangpur increased root growth and maintained the total carbohydrate pool. [•] Plant carbohydrate partitioning under water deficit was rootstock-dependent. [•] Young leaves and branches have similar importance as sources of carbohydrates. [Copyright &y& Elsevier]

Plants grown under inadequate mineralized nitrogen (N) levels undergo N and carbon (C) metabolic re-programming which leads to significant changes in both soluble and insoluble carbohydrate profiles. However, relatively little information is available on the genetic factors controlling carbohydrate partitioning during adaptation to N-limitation conditions in plants. A gene encoding a uridine-diphospho-(UDP)-glucose 4-epimerase (OsUGE-1) from rice (Oryza sativa) was found to be N-responsive. We developed transgenic rice plants to constitutively over-express the OsUGE-1 gene (OsUGE1-OX1–2). The transgenic rice lines were similar in size to wild-type plants at the vegetative stage and at maturity regardless of the N-level tested. However, OsUGE1-OX lines maintained 18–24% more sucrose and 12–22% less cellulose in shoots compared to wild-type when subjected to sub-optimal N-levels. Interestingly, OsUGE1-OX lines maintained proportionally more galactose and glucose in the hemicellulosic polysaccharide profile of plants compared to wild-type plants when grown under low N. The altered cell wall C-partitioning during N-limitation in the OsUGE1-OX lines appears to be mediated by OsUGE1 via the repression of the cellulose synthesis associated genes, OsSus1, OsCesA4, 7, and 9. This relationship may implicate a novel control point for the deposition of UDP-glucose to the complex polysaccharide profiles of rice cell walls. However, a direct relationship between OsUGE1 and cell wall C-partitioning during N-limitation requires further investigation. [ABSTRACT FROM AUTHOR]

Thermophilic microorganisms are attractive candidates for conversion of lignocellulose to biofuels because they produce robust, effective, carbohydrate-degrading enzymes and survive under harsh bioprocessing conditions that reflect their natural biotopes. However, no naturally occurring thermophile is known that can convert plant biomass into a liquid biofuel at rates, yields and titers that meet current bioprocessing and economic targets. Meeting those targets requires either metabolically engineering solventogenic thermophiles with additional biomass-deconstruction enzymes or engineering plant biomass degraders to produce a liquid biofuel. Thermostable enzymes from microorganisms isolated from diverse environments can serve as genetic reservoirs for both efforts. Because of the sheer number of enzymes that are required to hydrolyze plant biomass to fermentable oligosaccharides, the latter strategy appears to be the preferred route and thus has received the most attention to date. Thermophilic plant biomass degraders fall into one of two categories: cellulosomal (i.e. multienzyme complexes) and noncellulosomal (i.e. 'free' enzyme systems). Plant-biomass-deconstructing thermophilic bacteria from the genera Clostridium (cellulosomal) and Caldicellulosiruptor (noncellulosomal), which have potential as metabolic engineering platforms for producing biofuels, are compared and contrasted from a systems biology perspective. [ABSTRACT FROM AUTHOR]

Analyses of mutants impaired in assimilate export from chloroplasts revealed that carbohydrates as primary output of photosynthesis control expression of nuclear genes associated with plastidial processes such as acclimation to high light intensities.Retrograde signals from chloroplasts are thought to control the expression of nuclear genes associated with plastidial processes such as acclimation to varying light conditions. Arabidopsis mutants altered in the day and night path of photoassimilate export from the chloroplasts served as tools to study the involvement of carbohydrates in high light (HL) acclimation. A double mutant impaired in the triose phosphate/phosphate translocator (TPT) and ADP-glucose pyrophosphorylase (AGPase) (adg1-1/tpt-2) exhibits a HL-dependent depletion in endogenous carbohydrates combined with a severe growth and photosynthesis phenotype. The acclimation response of mutant and wild-type plants has been assessed in time series after transfer from low light (LL) to HL by analysing photosynthetic performance, carbohydrates, MgProtoIX (a chlorophyll precursor), and the ascorbate/glutathione redox system, combined with microarray-based transcriptomic and GC-MS-based metabolomic approaches. The data indicate that the accumulation of soluble carbohydrates (predominantly glucose) acts as a short-term response to HL exposure in both mutant and wild-type plants. Only if carbohydrates are depleted in the long term (e.g. after 2 d) is the acclimation response impaired, as observed in the adg1-1/tpt-2 double mutant. Furthermore, meta-analyses conducted with in-house and publicly available microarray data suggest that, in the long term, reactive oxygen species such as H2O2 can replace carbohydrates as signals. Moreover, a cross-talk exists between genes associated with the regulation of starch and lipid metabolism. The involvement of genes responding to phytohormones in HL acclimation appears to be less likely. Various candidate genes involved in retrograde control of nuclear gene expression emerged from the analyses of global gene expression. [ABSTRACT FROM AUTHOR]

Highlights: [•] Diurnal response of maize photosynthesis, nonstructural carbohydrates and ear dry matter were examined in response to N. [•] Nitrogen application increased plant N uptake, yield, leaf area, chlorophyll content, and soluble protein concentration. [•] Nitrogen application increased photosynthetic rates only during periods of high light intensities in the diurnal cycle. [•] Clear diurnal pattern of leaf sucrose and starch concentrations were found. [Copyright &y& Elsevier]

Background: The Three Gorges project has caused many ecosystem problems. Ecological restoration using readily-available plants is an effective way of mitigating environmental impacts. Two perennial submergence-tolerant ecotypes of Calamagrostis arundinacea were planted in an experimental field in the drawdown zone. Responses of the two plant ecotypes to flooding stress in the drawdown zone were unknown. Methodology/Principal Findings: Carbohydrate content and membrane stability, two key factors for survival of plants under flooding stress, of two ecotypes (designated “dwarf” and “green”) of C. arundinacea growing at different elevations of the drawdown zone were investigated. Live stems (LS) and dead stems (DS) of the two plant ecotypes at eight elevations (175, 170, 162, 160, 158, 155, 152 m and 149 m) were sampled. Contents of soluble sugar, starch and malondialdehyde (MDA), as well as plasma membrane permeability of live stems were measured. The lowest elevations for survival of dwarf and green C. arundinacea were 160 m and 158 m, respectively. Soluble sugar content of live stems of both ecotypes decreased with elevation, with amounts from an elevation of 170 m being lower than from an elevation of 175 m. MDA content and plasma membrane permeability in live stems of green C. arundinacea did not increase with the decrease in elevation, while these measures in dwarf C. arundinacea from an elevation of 162 m were significantly higher than from an elevation of 175 m. Conclusions: Carbohydrate content, especially soluble sugar content, in both ecotypes was more sensitive to flooding stress than membrane stability. Green C. arundinacea had a higher tolerance to submergence than dwarf C. arundinacea, and thus green C. arundinacea can be planted at lower elevations than dwarf C. arundinacea. [ABSTRACT FROM AUTHOR]

Highlights: [•] Carbohydrate content was determined in zucchini fruits during postharvest storage. [•] The raffinose is more likely related to dehydration than to chilling susceptibility. [•] Glucose, fructose, and pinitol could be involved in the adaptation to cold storage. [ABSTRACT FROM AUTHOR]

Many plant species are able to tolerate severe disturbance leading to removal of a substantial portion of the body by resprouting from intact or fragmented organs. Resprouting enables plants to compensate for biomass loss and complete their life cycles. The degree of disturbance tolerance, and hence the ecological advantage of damage tolerance (in contrast to alternative strategies), has been reported to be affected by environmental productivity. In our study, we examined the influence of soil nutrients (as an indicator of environmental productivity) on biomass and stored carbohydrate compensation after removal of aboveground parts in the perennial resprouter Plantago lanceolata. Specifically, we tested and compared the effects of nutrient availability on biomass and carbon storage in damaged and undamaged individuals. Damaged plants of P. lanceolata compensated neither in terms of biomass nor overall carbon storage. However, whereas in the nutrient-poor environment, root total non-structural carbohydrate concentrations (TNC) were similar for damaged and undamaged plants, in the nutrient-rich environment, damaged plants had remarkably higher TNC than undamaged plants. Based on TNC allocation patterns, we conclude that tolerance to disturbance is promoted in more productive environments, where higher photosynthetic efficiency allows for successful replenishment of carbohydrates. Although plants under nutrient-rich conditions did not compensate in terms of biomass or seed production, they entered winter with higher content of carbohydrates, which might result in better performance in the next growing season. This otherwise overlooked compensation mechanism might be responsible for inconsistent results reported from other studies. [ABSTRACT FROM AUTHOR]

Nonstructural carbohydrates (NSC) are frequently studied both by ecologists and plant physiologists because they serve as fundamental carbon and energy sources in plant metabolism. Because of the rapid enzymatic hydrolysis of NSC after harvest, plants are usually placed into liquid nitrogen until subsequent analyses in the laboratory. Nevertheless, when the research is performed in poorly accessible regions such as high mountains, tropical forests or deserts, the use of heavy containers containing vaporizing liquid nitrogen is problematic for logistical reasons. These places are particularly interesting as they harbor plant species with interesting physiological adaptations. In our study we aimed to develop a suitable storage method for plants intended for NSC analyses, which would require minimal equipment. These demands resulted in the idea of using the first step in NSC analyses - extraction in ethanol. Samples were extracted in 50 % and 96 % boiling or non-boiling ethanol and then stored for one month; they were compared with samples immediately frozen in liquid nitrogen. We discovered that for samples containing starch, fructans, soluble sugars and sugar alcohols, the best pretreatment for subsequent storage is extraction in 50 % or 96 % boiling ethanol. For total nonstructural carbohydrates (TNC) assessment, only extracting with 50 % ethanol without boiling gave very good results. Finally, we developed a method that could be used in any remote place without bulky laboratory equipment. [ABSTRACT FROM AUTHOR]

Abstract: Algal biomass is rich in carbohydrates which can be utilized as a promising source of substrate for dark fermentation. It becomes more significant when biomass is produced by capturing atmospheric greenhouse gas, CO2. In the present study, clean energy was generated in the form of biohydrogen utilizing algal biomass. Biohydrogen production was carried out by thermophilic dark fermentation using mixed culture. The culture of Chlorella sorokiniana was cultivated in helical airlift photobioreactor at 30 °C under continuous light intensity of 120 μmol m−2 s−1 provided by white fluorescent lamps. Biomass reached to stationary phase on 9th day giving maximum dry cell weight of 2.9 kg m−3. Maximum carbohydrate and protein content observed was 145 g kg−1 and 140 g kg−1, respectively. Maximum volumetric productivity of 334 g dm−3 d−1 was observed. Algal biomass was subjected to various physical and chemical pre-treatments processes for the improvement of hydrogen production. It was observed that the pretreatment with 200 dm3 m−3 HCl-heat was most suitable pretreatment method producing cumulative hydrogen of 1.93 m3 m−3 and hydrogen yield of 958 dm3 kg−1 volatile suspended solid or 2.68 mol mol−1 of hexose. Growth kinetics parameters such as μ max and K s were estimated to be 0.44 h−1 and 120 g m−3, respectively. The relationship between biomass and hydrogen production was simulated by the Luedeking–Piret model showing that H2 production is growth associated. The study thus showed the potential of algal biomass as substrate for biological hydrogen production. [Copyright &y& Elsevier]

Nonstructural carbohydrate (NSC) concentration in alfalfa (Medicago sativa L.) increases by cutting in the afternoon (PM) and wilting in wide swaths but the impact of this greater concentration during silage fermentation is not well known. We determined if increased NSC concentration associated with PM-cutting and wide swathing is maintained during fermentation and whether it affects conservation attributes of wilted alfalfa silages. The cutting time effect was measured in spring growth and summer regrowth of 2007 and 2008 (Experiment 1) while the combined effect of cutting time and swathing type was measured in spring growth and summer regrowth of 2008 (Experiment 2). Alfalfa was field wilted [≈390 g dry matter (DM) kg-1 fresh matter] and ensiled in mini-silos. Differences in alfalfa NSC concentration at ensiling (10 to 36 g kg-1 DM) due to PMcutting combined or not with wide swaths were reduced during silage fermentation to between 0 and 15 g kg-1 DM mostly through a reduction in soluble carbohydrate concentration. When NSC concentration differences at ensiling were > 10 g kg-1 DM, silage conservation attributes were improved with lower pH (-0.2 to -0.4), greater concentrations of lactate (+8 to +20 g kg-1 DM), and lower concentrations of volatile fatty acids (-8 to -11 g kg-1 DM) and NH3-N (-6 to -11 g kg-1 total N). Improved silage conservation attributes along with a greater residual starch concentration from NSC-enriched alfalfa has the potential to improve milk production. [ABSTRACT FROM AUTHOR]

Despite decades of research on plant drought tolerance, the physiological mechanisms by which trees succumb to drought are still under debate. We report results from an experiment designed to separate and test the current leading hypotheses of tree mortality. We show that piñon pine ( Pinus edulis) trees can die of both hydraulic failure and carbon starvation, and that during drought, the loss of conductivity and carbohydrate reserves can also co-occur. Hydraulic constraints on plant carbohydrate use determined survival time: turgor loss in the phloem limited access to carbohydrate reserves, but hydraulic control of respiration prolonged survival. Our data also demonstrate that hydraulic failure may be associated with loss of adequate tissue carbohydrate content required for osmoregulation, which then promotes failure to maintain hydraulic integrity. [ABSTRACT FROM AUTHOR]

Chia (Salvia hispanica L.) constitutes a potential alternative raw material and ingredient in food industry applications due to its dietary fiber content. Gumcan be extracted fromits dietary fiber fractions for use as an additive to control viscosity, stability, texture, and consistency in food systems. The gum extracted from chia seeds was characterized to determine their quality and potential as functional food additives. The extracted chia gum contained 26.2% fat and a portion was submitted to fat extraction, producing two fractions: gum with fat (FCG) and gum partly defatted (PDCG). Proximal composition and physicochemical characterization showed these fractions to be different (.. < 0.05). The PDCG had higher protein, ash, and carbohydrates content than the FCG, in addition to higher water-holding (110.5 g water/g fiber) and water-binding capacities (0.84 g water/g fiber). The FCG had greater oil-holding capacity (25.7 g oil/g fiber) and water absorption capacity (44 g water/g fiber). In dispersion trials, the gums exhibited a non-Newtonian fluid behavior, specifically shear thinning or pseudoplastic type. PDCG had more viscosity than FCG. Chia seed is an excellent natural source of gum with good physicochemical and functional qualities, and is very promising for use in food industry. [ABSTRACT FROM AUTHOR]

BACKGROUND Unavailable carbohydrates are an important limiting factor for utilization of palm kernel meal ( PKM) as aquafeed ingredients. The aim of this study was to improve available carbohydrate from PKM. Different physical modifications including water soaking, microwave irradiation, gamma irradiation and electron beam, were investigated in relation to chemical composition, physicochemical properties and in vitro carbohydrate digestibility using digestive enzymes from economic freshwater fish. RESULTS Modified methods had significant ( P < 0.05) effects on chemical composition by decreasing crude fiber and increasing available carbohydrates. Improvements in physicochemical properties of PKM, such as water solubility, microstructure, relative crystallinity and lignocellulosic spectra, were mainly achieved by soaking and microwave irradiation. Carbohydrate digestibility varied among the physical modifications tested ( P < 0.05) and three fish species had different abilities to digest PKM. Soaking was the appropriate modification for increasing carbohydrate digestion specifically in Nile tilapia ( Oreochromis niloticus), whereas either soaking or microwave irradiation was effective for striped snakehead ( Channa striata). For walking catfish ( Clarias batrachus), carbohydrate digestibility was similar among raw, soaked and microwave-irradiated PKM. CONCLUSION These findings suggest that soaking and microwave irradiation could be practical methods for altering appropriate physicochemical properties of PKM as well as increasing carbohydrate digestibility in select economic freshwater fish. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Effect of different CO2 concentrations on sucrose metabolizing enzymes and on carbohydrate metabolism was studied for eight blackgram (Vigna mungo L. Hepper) genotypes grown in open top chambers under ambient (380 μmol mol-1) vs. elevated CO2 (550 and 700 μmol mol-1) levels. The higher acid invertase activity over neutral invertase indicated the major role of acid invertase in sucrose breakdown. Higher acid invertase activity over Sucrose Synthase (SuSy) suggested the major role of invertase in sucrose breakdown and sucrolysis. Sucrose Phosphate Synthase (SPS) activity did not match with sucrose pool sizes in mature leaves and rather varied among genotypes. Plants exposed to higher CO2 concentrations showed higher starch and sucrose contents as compared with those exposed to ambient CO2. Leaf starch content being found several-folds higher than sucrose throughout the study indicated its major role in regulating assimilate partitioning. Increase in glucose vs. fructose concentrations for genotypes grown under elevated CO2 conditions ranged from 20 to 90% and from 10 to 140%, respectively. The hexoses/sucrose ratio for elevated CO2 concentration was approximately 0.8-1.6, however for ambient CO2 content it approximately amounted to unity. Genotypes IC436720, IC519805, IC343952, and IC282009 with low hexose/sucrose ratio representing high CO2 assimilation along with high sucrose formation indicated better tolerance to elevated CO2 for carbon partitioning and carbohydrate metabolism. The up-regulation of leaf carbohydrate metabolizing enzymes of low hexose/sucrose as well as low sucrose/starch ratios for the genotype IC436720 (as compared with other genotypes) improved its photosynthetic capability which coupled with its better efficiency of carbon partitioning (indicative of better acclimation to elevated CO2) could prove beneficial to its growth and productivity in the future change of climatic conditions. [ABSTRACT FROM AUTHOR]

Abstract: Angelicae Sinensis radix (ASR) and Chuanxiong Rhizoma (CR) are two commonly used herbs with different blood-related bioactivities for tonic and medicinal purpose, respectively. However, current available scientific evidences indicate that they share similar chemical profiles in which volatile components are the majority. In order to figure out the decisive chemical differences and then establish their individual quality control methods, comprehensive comparison on chemical ingredients between ASR and CR was carried out in this study. First, volatile components between ASR and CR were determined and compared by GC–MS (gas chromatography–mass spectrometry). Then, carbohydrates and polysaccharides in ASR and CR were qualitatively and quantitatively characterized using HPGPC (high performance gel permeation chromatography) and HPLC (high performance liquid chromatography). Furthermore, these components in different botanical parts and processed products of ASR were also investigated. The results not only confirmed that ASR and CR contain similar profiles of volatile components, but also suggested that the volatile components might not be the nutrient ingredients of ASR and that the polysaccharides make the real differences between ASR and CR. [Copyright &y& Elsevier]

Among starchy seeds, rice has the unique capacity to germinate successfully under complete anaerobiosis. In this conditions, starch degradation is supported by a complete set of starch-degrading enzymes that are absent or inactive in cereals except rice. A characterization of carbohydrate metabolism and starch-degrading enzyme activity across twenty-nine genotypes of Oryza sativa L. is presented here. The zymogram of amylolytic activities present in rice embryos and endosperms under anaerobic conditions seven days after sowing (DAS) revealed marked differences among cultivars. Coleoptile elongation was positively correlated with total amylolytic activities and α-amylase activity in embryos, and negatively correlated with α-amylase activity in endosperm. Moreover, carbohydrate content in embryos was found to be positively correlated with total amylolytic activities under anaerobic conditions, while a negative relationship was recorded in the endosperm. Carbohydrate status in rice seedlings has a primary importance in sustaining coleoptile elongation towards the surface. The relationship between carbohydrate level in embryo and anoxic germination, as well as with total amylolytic activities present in rice embryo under anaerobic condition 7 DAS, is consistent with the role of sugar metabolism to support rice germination under oxygen-deprived environment. [ABSTRACT FROM AUTHOR]

Climate-induced tree mortality is an increasing concern for forest managers around the world. We used a coupled hydrologic and ecosystem carbon cycling model to assess temperature and precipitation impacts on productivity and survival of ponderosa pine (Pinus ponderosa). Model predictions were evaluated using observations of productivity and survival for three ponderosa pine stands located across an 800 m elevation gradient in the southern Rocky Mountains, USA, during a 10-year period that ended in a severe drought and extensive tree mortality at the lowest elevation site. We demonstrate the utility of a relatively simple representation of declines in non-structural carbohydrate (NSC) as an approach for estimating patterns of ponderosa pine vulnerability to drought and the likelihood of survival along an elevation gradient. We assess the sensitivity of simulated net primary production, NSC storage dynamics, and mortality to site climate and soil characteristics as well as uncertainty in the allocation of carbon to the NSC pool. For a fairly wide set of assumptions, the model estimates captured elevational gradients and temporal patterns in growth and biomass. Model results that best predict mortality risk also yield productivity, leaf area, and biomass estimates that are qualitatively consistent with observations across the sites. Using this constrained set of parameters, we found that productivity and likelihood of survival were equally dependent on elevation-driven variation in temperature and precipitation. Our results demonstrate the potential for a coupled hydrology-ecosystem carbon cycling model that includes a simple model of NSC dynamics to predict drought-related mortality. Given that increases in temperature and in the frequency and severity of drought are predicted for a broad range of ponderosa pine and other western North America conifer forest habitats, the model potentially has broad utility for assessing ecosystem vulnerabilities. [ABSTRACT FROM AUTHOR]

Background: Potato (Solanum tuberosum) is one of the most important sources of carbohydrates in human diet. Because of its high carbohydrate levels it recently has also received attention in biohydrogen production. To exploit the natural variation of potato with respect to resistance to major diseases, carbohydrate levels and composition, and capacity for biohydrogen production we analyzed tubers of native, improved, and genetically modified potatoes, and two other tuberous species for their glucose, fructose, sucrose, and starch content. Results: High-starch potato varieties were evaluated for their potential for Caldicellulosiruptor saccharolyticus-mediated biohydrogen production with Desirée and Rosita varieties delivering the highest biohydrogen amounts. Native line Vega1 and improved line Yagana were both immune to two isolates (A291, A287) of Phytophthora infestans. Conclusions: Our data demonstrate that native potato varieties might have great potential for further improving the multifaceted use of potato in worldwide food and biohydrogen production. [ABSTRACT FROM AUTHOR]

Abstract: Stripe rust is the most serious wheat disease worldwide. Puccinia striiformis f. sp. tritici (Pst), which is the causal agent of stripe rust, is an obligate biotrophic fungus and must take up nutrients from the host through its haustoria. Recent studies have indicated that sugar is the main nutrient taken up by pathogens from host cells. However, the response of sugars to Pst infection in wheat is not well known. In this study, the levels of water-soluble carbohydrates in Pst-infected wheat leaves were investigated, and the results revealed slight changes for all of the carbohydrates except sucrose. Furthermore, the sucrose levels increased in both the compatible and incompatible systems. The photosynthetic rates of infected leaves were determined and found to be significantly increased during the early stage of Pst infection. In addition, the expression profiles of genes associated with photosynthesis were assayed through real-time PCR, and the trends found were identical to that observed for the photosynthetic rate in Pst-infected wheat leaves. These findings indicate that Pst infection can upregulate genes involved in photosynthesis to promote the photosynthetic rate and ultimately induce sucrose accumulation in infected wheat leaves. [Copyright &y& Elsevier]

The objective of this study was to evaluate the variation of carbohydrates, proteins and free amino acids in vine leaves in cv. Italy under different levels in different phases phenological defoliation. The experimental design was randomized blocks in factorial scheme 4 (5, 10, 15 and 20 sheets left in the industry) X 4 (phenological phases at 60, 72, 84 and 106 days after pruning) and three replications. We selected leaves were exposed to sunlight, fully extended, opposite the bunch, with no signs of senescence and healthy for the indirect measurement of chlorophyll (chlorophyll index) in SPAD readings using portable chlorophyll meter SPAD-502. The leaves were subjected to quantitative analysis of proteins, amino acids, starch, total sugars, reducing sugars and sucrose. The starch content was high in the initial softening of berries and sheets 15 left on the field of production and low at the start of the ripening of fruits. 15 The amount of leaves left on the branches of production in grapevine cv. Italy is recommended, therefore, these plants showed greater efficiency in both transmission and reserve accumulation and this accumulation was influenced by the phenological stage of grapevine. [ABSTRACT FROM AUTHOR]

Carbohydrates and their metabolizing enzymes related to sweetness and glutinosity were measured in the fresh waxy corn of ' Zhongnuo 1' and ' Jingkenuo 2000' cultivars during storage for 4 days at 20C. The contents of sugars decreased to a lesser degree in 'Jingkenuo 2000' compared to those of ' Zhongnuo 1,' and both cultivars exhibited similar trends in starch content. The amylopectin and total starch contents both increased significantly and then gradually decreased, whereas the amylose content significantly increased. Furthermore, the activities of both uridine diphosphate glucose pyrophosphorylase ( UGPase) and starch debranched enzyme exhibited a similar pattern with a single peak curve. The activities of adenosine diphosphate glucose pyrophosphorylase ( AGPase) and soluble starch synthase decreased, whereas the activity of granule-bound starch synthase ( GBSS) increased significantly. The activity of the starch-branching enzyme was mostly constant. Correlation analysis between carbohydrates and metabolizing enzymes indicates that UGPase, AGPase and GBSS may be important enzymes. Practical Applications Fresh waxy corn is widely eaten because of its sweetness and glutinosity, which are the eternal behaviors of related carbohydrate character. Contrary to other fruits and vegetables with high soluble sugar and water content, fresh waxy corn shows high starch content and low water content. Thus, the physiological basis for changes in eating quality may differ between fresh waxy corn and other fruits and vegetables. That means the postharvest changes in carbohydrates of common fruits and vegetables are not applicable to instruct the storage and retail of fresh waxy corn. In this study, we report the changes of related carbohydrates and associated enzyme activities and the correlations between them. The research realizes the reason for eating quality changing and controlling factors. These results can promote the quality of fresh waxy corn in the processing, storage and retail. [ABSTRACT FROM AUTHOR]

Highlights: [•] Frost tolerance of Festuca pratensis was improved under low temperature flooding. [•] Higher carbohydrate concentration may trigger stable frost tolerance increases. [•] Changes in gene expression was related to transient frost tolerance increases. [•] In more frost tolerant genotypes flooding increases photoinhibition resistance. [Copyright &y& Elsevier]

To determine the contribution of polar auxin transport (PAT) to auxin accumulation and to adventitious root (AR) formation in the stem base of Petunia hybrida shoot tip cuttings, the level of indole-3-acetic acid (IAA) was monitored in non-treated cuttings and cuttings treated with the auxin transport blocker naphthylphthalamic acid (NPA) and was complemented with precise anatomical studies. The temporal course of carbohydrates, amino acids and activities of controlling enzymes was also investigated. Analysis of initial spatial IAA distribution in the cuttings revealed that approximately 40 and 10 % of the total IAA pool was present in the leaves and the stem base as rooting zone, respectively. A negative correlation existed between leaf size and IAA concentration. After excision of cuttings, IAA showed an early increase in the stem base with two peaks at 2 and 24 h post excision and, thereafter, a decline to low levels. This was mirrored by the expression pattern of the auxin-responsive GH3 gene. NPA treatment completely suppressed the 24-h peak of IAA and severely inhibited root formation. It also reduced activities of cell wall and vacuolar invertases in the early phase of AR formation and inhibited the rise of activities of glucose-6-phosphate dehydrogenase and phosphofructokinase during later stages. We propose a model in which spontaneous AR formation in Petunia cuttings is dependent on PAT and on the resulting 24-h peak of IAA in the rooting zone, where it induces early cellular events and also stimulates sink establishment. Subsequent root development stimulates glycolysis and the pentose phosphate pathway. [ABSTRACT FROM AUTHOR]

We measured lipid, carbohydrate and protein content in three strains of cotton aphid,Aphis gossypii(Hemiptera: Aphididae) from very resistant to neonicotinoids up to semi sensitive and sensitive strains in different exposure method of spraying to neonicotinoids. We observed changes in energy source rates at which each substrate was metabolised under starvation, selection and residue stress method spraying that assist in metabolisation of their biochemical parameters. These particular exposure methods influenced some of biochemical parameters in cotton aphid. Results indicated that Sugar, glycogen, total protein and lipid in aphids have significant changes. Studies showed that among three strains called Ag-R, Ag-M and Ag-D which have different susceptibilities to neonicotinoids, strain Ag-R was the most tolerated aphids in counter of imidacloprid and thiametoxam, strain Ag-D was somewhat more tolerated to these insecticides and strain Ag-M was the most sensitive strain which has the resistance factor of nearly 890 in starvation method and was different depending on the method of exposure. Among energy sources, the total lipid in susceptible strain were decreasing more than resistant strain, whereas total proteins were increasing in resistant strain compared with sensitive strain. Total Glycogen was affected significantly in the stress condition which caused an increase and was the most resistant strain. [ABSTRACT FROM PUBLISHER]