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Sugar Alcohol (sugar + alcohol)
Selected AbstractsBase-free Pd/TOMPP-Catalyzed Telomerization of 1,3-Butadiene with Carbohydrates and Sugar AlcoholsCHEMSUSCHEM CHEMISTRY AND SUSTAINABILITY, ENERGY & MATERIALS, Issue 9 2009Peter J. Sugar and alcohol,a superior combo: The telomerization activity of the Pd/TOMPP catalyst is screened using thirteen different biomass-derived carbohydrates and sugar alcohols. High substrate conversions are achieved by using low Pd loading and without the use of an added base. In terms of butadiene conversion, a clear structure,activity relationship is found, which is in line with the series: sugar,alcohols>sucrose>aldohexoses>aldopentoses>ketohexoses. [source] Maternal control of cold and desiccation tolerance in eggs of the band-legged ground cricket Dianemobius nigrofasciatus in relation to embryonic diapauseENTOMOLOGICAL RESEARCH, Issue 1 2008Shin G. GOTO Abstract Cold and desiccation tolerance was investigated in the eggs of the band-legged ground cricket Dianemobius nigrofasciatus in relation to embryonic diapause. Diapause eggs were more tolerant to both desiccation and cold than non-diapause eggs. In addition, diapause-destined eggs on day zero (0,12 h after being laid) already showed high tolerance to these stresses before entering diapause. This clearly indicates that stress tolerance, like diapause, is controlled by photoperiod, but is not directly associated with diapause itself. Because the acquisition of stress tolerance predates the onset of diapause, it is plausible that diapause programming during some period before the onset of diapause is involved in the acquisition of stress tolerance. Weights and sizes were nearly identical in short-day and long-day eggs until day five. Sorbitol, a major sugar alcohol in eggs of D. nigrofasciatus, was accumulated at the same level in short-day and long-day eggs on days zero and five. These results indicate that the surface-to-volume ratio as well as the accumulation of sugar alcohol is not involved in the acquisition of stress tolerance. Maternal factors are clearly involved in the acquisition of stress tolerance in D. nigrofasciatus eggs, but the physiological mechanisms underlying the tolerance are still unclear. [source] EFFECT OF ERYTHRITOL ON QUALITY CHARACTERISTICS OF REDUCED-CALORIE DANISH COOKIESJOURNAL OF FOOD QUALITY, Issue 2010SHENG-DUN LIN ABSTRACT The effects of erythritol on the quality characteristics of Danish cookies were studied. Danish cookies were formulated using erythritol as a sweetener to replace 0, 25, 50, 75 and 100% sucrose. The results showed that Hunter L -values and erythritol contents of cookies increased with increasing erythritol level whereas there was no difference in the moisture, protein, fat, ash and hardness of cookies prepared with sucrose or erythritol. The erythritol was stable during baking. In descriptive analysis, the surface color of cookies became lighter, and the sweetness of cookies became less sweet as erythritol level increased and sucrose decreased. The 50, 75 and 100% erythritol cookies had a cooling sensation. The moistness and hardness of cookies showed no difference among all samples. In hedonic test, the degree of surface color, sweetness, hardness, flavor and overall liking of cookies prepared with 0, 25 and 50% replacement of sucrose with erythritol revealed no difference. However, lower degree of sensory qualities (except hardness) liking of 75 and 100% erythritol cookies was observed. PRACTICAL APPLICATIONS Sucrose is one of the principal ingredients of cookies. But a sucrose-rich diet had been proven to be associated with lipogenesis and obesity. Erythritol is a sugar alcohol and has a good tolerance by humans. It is a noncariogenic, nonglycemic and low-calorie sweetener that is safe for diabetics. In addition, it possesses antioxidant properties. The study explores the possibility of utilizing erythritol to produce acceptable cookies. [source] Expression of a celery mannose 6-phosphate reductase in Arabidopsis thaliana enhances salt tolerance and induces biosynthesis of both mannitol and a glucosyl-mannitol dimerPLANT CELL & ENVIRONMENT, Issue 2 2003G. ZHIFANG ABSTRACT Mannitol, a sugar alcohol that may serve as a compatible solute to cope with salt stress, is synthesized via the action of a mannose-6-phosphate reductase (M6PR) in celery (Apium graveolens L). In contrast to previous approaches that have used a bacterial gene to engineer mannitol biosynthesis in plants and other organisms, Arabidopsis thaliana, a non-mannitol producer, was transformed with the celery leaf M6PR gene under control of the CaMV 35S promotor. In all independent Arabidopsis M6PR transformants, mannitol accumulated throughout the plants in amounts ranging from 0·5 to 6 µmol g,1 fresh weight. A novel compound, not found in either celery or Arabidopsis, 1-O- , - d -glucopyranosyl- d -mannitol, also accumulated in vegetative tissues of mature plants in amounts up to 4 µmol g,1 fresh weight, but not in flowers and seeds. In the absence of NaCl, all transformants were phenotypically the same as the wild type; however, in the presence of NaCl, mature transgenic plants showed a high level of salt tolerance, i.e. growing, completing normal development, flowering, and producing seeds in soil irrigated with 300 mm NaCl in the nutrient solution. These results demonstrate a major role in developing salt-tolerant plants by means of introducing mannitol biosynthesis using M6PR. [source] Effect of D-mannitol on feed digestion and cecotrophic system in rabbitsANIMAL SCIENCE JOURNAL, Issue 2 2009Hamza HANIEH ABSTRACT This study aimed to evaluate the effect of sugar alcohol as an energy source for cecal microbes on digestibility, cecotrophy (i.e. reingestion of microbial products of cecum, cecotrophs) and performance in rabbits. Thus, we fed rabbits an experimental diet that included 5% of D-mannitol, and collected hard feces and cecotrophs to be analyzed for crude protein (CP), acid detergent fiber (ADF), ether extract (EE), crude ash (CA) and dry matter (DM). Cecotrophic behavior of the rabbits was also observed. Feeding D-mannitol increased (P < 0.01) digestibility of ADF, resulting in a decrease (P < 0.05) in the concentration in hard feces. The increase (P < 0.05) in CP concentration was attributed to lower (P < 0.05) digestibility. D-mannitol had a similar modulatory effect on CP and ADF concentrations in hard feces and cecotrophs. Accordingly, estimations of the proportion of nutrients recycled by cecotrophy to dietary intake (PR), obtained by the two calculation methods, showed an increase (P < 0.01) in PR of CP and a decrease (P < 0.05) in that of ADF. Daily weight gain and feed efficiency increased (P < 0.05) for D-mannitol-fed rabbits, while daily feed intake decreased (P < 0.05). These results suggest the possibility of using D-mannitol as a stimulator of cecal microbial growth and cellulolytic activity, and therefore, improved rabbits performance. [source] Resistance of apple trees to Cydia pomonella egg-laying due to leaf surface metabolitesENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 1 2008Nadia Lombarkia Abstract During host plant selection and particularly after alighting on a plant, chemical cues from the plant surface influence an insect's acceptance of the plant and, subsequently, its egg-laying behaviour. Primary metabolites in the phylloplane may be more important than hitherto known. We have shown that soluble carbohydrates, such as glucose, fructose, and sucrose, and sugar alcohols, such as sorbitol, quebrachitol, and myo -inositol, can be detected by insects after contacting the plant and that they positively influence egg-laying of the codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae), on apple trees. We addressed the question whether a lack of these substances could also explain apple tree resistance to C. pomonella in terms of reduced egg-laying. Leaf surface washings were collected in an apple orchard by spraying water on the resistant cultivar X65-11 and on the susceptible cultivar P5R50A4. The washings were tested on a nylon cloth on isolated females under no-choice conditions. The washings were analysed and synthetic blends, each consisting of the six metabolites in the proportions established in the leaf surface washings of both cultivars, were then tested for their effect on egg-laying of C. pomonella. Dose,response egg-laying tests were carried out on substrates impregnated with the X65-11 leaf surface blend at 1, 100, 1 000, and 10 000 times the natural dose. Egg-laying behaviour in the bioassays with leaf surface washings of both cultivars closely resembled egg-laying in the orchard. Washings of P5R50A4 stimulated egg-laying to a greater extent than those of X65-11 and the water control. Synthetic blends reduced substrate acceptance and egg-laying, compared to the washings of X65-11. Ratios between components within the blend are responsible for this resistance. In conclusion, quantities and ratios of the six primary metabolites found on the leaf surface may influence host preference of C. pomonella as well as their egg-laying behaviour, thus they may play a role in the trees' resistance to the codling moth. [source] Utilization of oligo- and polysaccharides at microgram-per-litre levels in freshwater by Flavobacterium johnsoniaeJOURNAL OF APPLIED MICROBIOLOGY, Issue 4 2010E.L.W. Sack Abstract Aims:, To obtain a bacterial strain that can be used to quantify biodegradable polysaccharides at concentrations of a few micrograms per litre in freshwater. Methods and Results:,Flavobacterium johnsoniae strain A3 was isolated from tap water supplemented with laminarin, pectin or amylopectin at 100 ,g C l,1 and river Rhine water. The organism utilized 14 of 23 oligo- and polysaccharides, and 1 of 9 monosaccharides, but none of the sugar acids, sugar alcohols, carboxylic acids or aromatic acids tested at 10 ,g C l,1. Amino acids promoted growth of strain A3, but not in coculture with assimilable organic carbon (AOC) test strain Pseudomonas fluorescens P17, which utilized these compounds more rapidly than strain A3. Compounds released by strain P17 and AOC test strain Spirillum sp. NOX grown on acetate promoted the growth of strain A3 at Nmax values of , 2 × 105 CFU ml,1 of strain P17 and , 5 × 105 CFU ml,1 of strain NOX. Significant growth of strain A3 was observed in surface water and in tap water in the presence of strain P17 (Nmax P17 < 2 × 105 CFU ml,1). Conclusions:, Strain A3 utilizes oligo- and polysaccharides at microgram-per-litre levels. In surface water and in tap water, the organism was able to utilize compounds that were not utilized by strain P17. These compounds may include oligo- and/or polysaccharides. Significance and Impact of the Study:, Phytoplanktonic and bacterial polysaccharides can constitute an important biodegradable fraction of natural organic matter in water and may promote growth of heterotrophic bacteria during water treatment and drinking water distribution. Strain A3 can be used to quantify a group of compounds that includes oligo- and polysaccharides at microgram-per-litre levels in freshwater. [source] Effects of Saccharide Set Retarders on the Hydration of Ordinary Portland Cement and Pure Tricalcium SilicateJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 1 2010Linghong Zhang The effects of aliphatic sugar alcohols (e.g., threitol, xylitol, sorbitol) on the hydration of tricalcium silicate (C3S) and ordinary portland cement (OPC) were investigated and compared with those of sucrose, a well-established cement set retarder. Only sugar alcohols which contain threo diol functionality retarded the setting of C3S and OPC, their efficacy increasing with the number of threo hydroxy pairs and, to a smaller extent, with the overall population of hydroxy groups. None, however, were as effective as sucrose. The initial and final setting times increased exponentially with the concentration of saccharide, although the hydration of OPC was less inhibited than that of C3S. Saccharides function as "delayed accelerators," that is, cement hydration is first inhibited and then proceeds faster than in saccharide-free cement. This behavior is consistent with the theory that the induction period is controlled by slow formation and/or poisoning of the stable calcium silicate hydrate (CSH) nuclei. The early inhibiting influence of saccharides on CSH precipitation is apparently stronger than on the growth of crystalline calcium hydroxide. Saccharides did not negatively affect the degree of hydration and compressive strength of fully set OPC paste; on the contrary, sorbitol yielded modest increases. [source] Base-free Pd/TOMPP-Catalyzed Telomerization of 1,3-Butadiene with Carbohydrates and Sugar AlcoholsCHEMSUSCHEM CHEMISTRY AND SUSTAINABILITY, ENERGY & MATERIALS, Issue 9 2009Peter J. Sugar and alcohol,a superior combo: The telomerization activity of the Pd/TOMPP catalyst is screened using thirteen different biomass-derived carbohydrates and sugar alcohols. High substrate conversions are achieved by using low Pd loading and without the use of an added base. In terms of butadiene conversion, a clear structure,activity relationship is found, which is in line with the series: sugar,alcohols>sucrose>aldohexoses>aldopentoses>ketohexoses. [source] | |||||||||||||