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Starch Breakdown (starch + breakdown)
Selected AbstractsEnvironmental and hormonal regulation of the activity,dormancy cycle in the cambial meristem involves stage-specific modulation of transcriptional and metabolic networksTHE PLANT JOURNAL, Issue 4 2007Nathalie Druart Summary We have performed transcript and metabolite profiling of isolated cambial meristem cells of the model tree aspen during the course of their activity,dormancy cycle to better understand the environmental and hormonal regulation of this process in perennial plants. Considerable modulation of cambial transcriptome and metabolome occurs throughout the activity,dormancy cycle. However, in addition to transcription, post-transcriptional control is also an important regulatory mechanism as exemplified by the regulation of cell-cycle genes during the reactivation of cambial cell division in the spring. Genes related to cold hardiness display temporally distinct induction patterns in the autumn which could explain the step-wise development of cold hardiness. Factors other than low temperature regulate the induction of early cold hardiness-related genes whereas abscisic acid (ABA) could potentially regulate the induction of late cold hardiness-related genes in the autumn. Starch breakdown in the autumn appears to be regulated by the ,short day' signal and plays a key role in providing substrates for the production of energy, fatty acids and cryoprotectants. Catabolism of sucrose and fats provides energy during the early stages of reactivation in the spring, whereas the reducing equivalents are generated through activation of the pentose phosphate shunt. Modulation of gibberellin (GA) signaling and biosynthesis could play a key role in the regulation of cambial activity during the activity,dormancy cycle as suggested by the induction of PttRGA which encodes a negative regulator of growth in the autumn and that of a GA-20 oxidase, a key gibberellin biosynthesis gene during reactivation in spring. In summary, our data reveal the dynamics of transcriptional and metabolic networks and identify potential targets of environmental and hormonal signals in the regulation of the activity,dormancy cycle in cambial meristem. [source] Effect of three lipid/hydrocolloid coatings on shelf life stability of Golden Delicious applesINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 9 2007Frank D. Conforti Summary The shelf life quality of freshly harvested Golden Delicious apples coated with three individually developed lipid/hydrocolloid coatings was assessed throughout refrigerated storage. The apples were monitored for 8 weeks. The coatings resulted in low internal O2 and the least loss of fruit firmness when compared with the non-coated apple group. The coated apples had very little starch breakdown, minimum flesh colour development, or loss of titratable acidity content. Soluble solids and fresh weight loss remained unchanged for both the non-coated and coated groups. Sensory analysis confirmed that the coated apples maintained consistent quality in firmness, crispness and juiciness throughout the storage period. [source] INHIBITORY POTENTIAL OF WINE AND TEA AGAINST ,-AMYLASE AND ,-GLUCOSIDASE FOR MANAGEMENT OF HYPERGLYCEMIA LINKED TO TYPE 2 DIABETESJOURNAL OF FOOD BIOCHEMISTRY, Issue 1 2008YOUNG-IN KWON ABSTRACT Natural ,-amylase and ,-glucosidase inhibitors from food-grade plants offer an attractive strategy to manage postprandial hyperglycemia for type 2 diabetes management via control of starch breakdown and intestinal glucose absorption. In this study, four random sources of red and white wines as well as four types of teas were investigated for ,-amylase and ,-glucosidase inhibitory potential. Water extracts of black tea had the highest ,-glucosidase inhibitory activity, followed by white tea and oolong tea. All the randomly selected red wines had significant ,-glucosidase inhibitory activity compared to white wine. The ,-glucosidase inhibitory activity of the tea and wines correlated to the phenolic content, antioxidant activity and phenolic profile of the extracts. Further, these extracts had less or no ,-amylase inhibitory activity, indicating potential to overcome the side effects of undigested starch. This research has relevance for managing hyperglycemia and related oxidation-linked dysfunction and concurrently reducing problems of undigested starch. PRACTICAL APPLICATIONS In this study anti-diabetic-relevant potential of wines and teas were confirmed in four types of red and white wines as well as four types of commonly available teas using in vitro enzyme assays for alpha-glucosidase and alpha-amylase inhibitory activities. In vitro inhibitory activities of these enzymes provide a strong biochemical rationale for further in vivo studies and dietary management strategy for type 2 diabetes through the control of glucose absorption. Further this phenolic antioxidant-enriched dietary strategy using specific beverage combinations can generate a whole food profile that has the potential to reduce hyperglycemia-induced pathogenesis and also associated complications linked to cellular oxidation stress. [source] Mechanical flower thinning improves the fruit quality of applesJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 5 2010Alexey A Solomakhin Abstract BACKGROUND: Apple ,Golden Delicious Reinders' and ,Gala Mondial' trees were mechanically blossom-thinned with 30,77 × g (300,480 rpm rotation) and 5 or 7.5 km h,1 vehicle speed to improve fruit quality, minimise leaf damage, reduce hand and chemical thinning and to prevent or overcome alternate bearing; adjacent untreated or manually thinned apple trees served as controls. RESULTS: Mechanical thinning (43 × g, 360 rpm, 5,7.5 km h,1) had a positive effect on fruit size (15% larger), firmness (8.4 in Gala vs. 7.6 kg cm,2 in the unthinned control), sweetness (124 vs. 117 g kg,1 sugar in the control), contained the largest malic acid content (4 g kg,1 vs. 3.4 g kg,1 in the control) and 17% more anthocyanin (normalised anthocyanin index = 0.8 in Gala vs. 0.7 in the control); fruit of Golden and Gala showed additionally advanced starch breakdown and ripened earlier. CONCLUSIONS: Since increases in rotor speed, viz. centrifugal force, versus increases in the vehicle speed resulted in opposing effects, an integrated coefficient of thinning (ICT) was devised with optimum values of 10,40 (at 43 × g, 5,7.5 km h,1), where an ICT > 50 led to tree damage and ICT < 8 led to sub-optimum thinning efficacy. Copyright © 2010 Society of Chemical Industry [source] |