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In higher plants, asparagine-linked oligosaccharides (N-glycans) in glycoproteins carry unique carbohydrate epitopes, namely, a core α1,3-fucose and/or a β1,2-xylose, which are common determinants responsible for the cross-reactivity of plant glycoproteins due to their strong immunogenicity. While
We evaluated whether changes in fine root non-structural carbohydrate reserves of Fagus sylvatica and Pinus sylvestris trees influence potential enzymatic activities of their ectomycorrhizal symbionts from winter towards spring reactivation, and whether these changes influence potential soil
Monitoring cambial phenology and intra-annual growth dynamics is a useful approach for characterizing the tree growth response to climate change. However, there have been few reports concerning intra-annual wood formation in lowland temperate forests with high time resolution, especially for the
We investigated soluble carbohydrate transport in trees that differed in their phloem loading strategies in order to better understand the transport of photosynthetic products into the roots and the rhizosphere as this knowledge is needed to better understand the respiratory processes in the
The plasma glucose and insulin responses were determined in 10 NIDDM female patients following the ingestion of tropical fruit containing 25 g of carbohydrate. The five tropical fruits were pineapple, mango, banana, durian and rambutan. Blood was drawn at 0, 30, 60, 120 and 180 min, respectively.
Elevated concentrations of carbon dioxide ([CO2]) and ozone ([O3]) affect primary metabolism of trees in opposite ways. We studied their potential interactions on carbohydrate concentrations and contents. Two hypotheses currently under debate were tested. (1) Stimulation of primary metabolism by
Nonstructural carbohydrates (NSC) are the most important C reserves in the tissues of deciduous and evergreen tree species. Besides NSC, cell-wall hemicelluloses as the second most abundant polysaccharides in plants have often been discussed to serve as additional mobile carbon (C) reserves during
Severe drought events threaten tree water transport system, productivity and survival. Woody angiosperms generally die when embolism-induced loss of hydraulic conductance (PLC) surpasses 80-90% under intense water shortage. However, the recovery capability and possible long-term carry-over effects
Beginning in 1985, plots in a 120-year-old beech (Fagus sylvatica L.) stand in the province of Scania, southern Sweden were fertilized annually with ammonium nitrate. In August 1989, leaves from both fertilized and unfertilized trees were analyzed for mineral nutrients, soluble carbohydrates, amino
In a water-exclusion experiment, five different ecotypes of beech (Fagus sylvatica L.; representing regions of different environmental and climatic conditions in Baden-Württemberg, Germany) were subjected to drought conditions of different severity between July and September of two consecutive
Carbon isotope composition (δ(13)C) and carbohydrate content of phloem sap and fine roots were measured in a Mediterranean beech (Fagus sylvatica L.) forest throughout the growing season to study seasonal changes of source-sink relationships. Seasonal variations of δ(13)C and content of phloem sap
Beech seedlings were grown under different nitrogen fertilisation regimes (0, 20, 40, and 80 kg Nha(-1)yr(-1)) for three years and were fumigated with either charcoal-filtered (F) or ambient air (O3). Nitrogen fertilisation increased leaf necroses, aphid infestations, and nutrient ratios in the
The freeze-tolerant wood frog, Rana sylvatica, is one of few vertebrate organisms that can tolerate freezing, with up to 70% of its total body water being converted into extracellular ice. Physiologically, wood frogs show no signs of muscle movement, breathing, heartbeat, or brain activity
Excessive dietary fat intake causes systemic metabolic toxicity, manifested in weight gain, hyperglycemia, and insulin resistance. In addition, carbohydrate utilization as a fuel is substantially inhibited. Correction or reversal of these effects during high-fat diet (HFD) intake is of exceptional
We tested the hypothesis that broad-leaved forest species with contrasting wood anatomy and hydraulic system (ring-porous versus diffuse-porous) also differ in distribution and seasonal dynamics of carbohydrate reserves in stem wood. Total nonstructural carbohydrate (TNC) reserves (starch and