Carbohydrates in Grasses. I. Sugar and Fructosan Composition of the Stem Bases of Several Northern‐Adapted Grasses at Seed Maturity¹

Abstract

Extraction of the stem base tissue of timothy, orchardgrass, and redtop at near seed maturity with concentrations of ethanol from 95 to 0% yielded steadily increasing percentages of carbohydrates, indicating a series of fructosans of increasing chain length. Reed canarygrass and Kentucky bluegrass tissue also yielded increasing percentages, but not continuously so. Fructosans in all of the above species were predominantly of long‐chain length. Bromegrass,t all rescue, ryegrass, and quackgrass tissue yielded no additional carbohydrate at low ethanol concentrations, indicating that the fructosans present were relatively short‐chain polymers.Concentration of the ethanol must be considered in separating free sugars from low molecular weight fructosans, or otherwise some of the fructosans may De extracted along with the sugars. Thin layer chromatography showed that 85% ethanol was the most suitable concentration with which to extract the free sugars from the fructosans in those species containing predominantly long‐chain fructosans. With the species containing predominantly short‐chain fructosans, 90% ethanol was most suitable. More dilute ethanol solutions extracted short‐chain fructose polymers along with the glucose, fructose, and sucrose.Glucose, fructose, and sucrose constituted only a small part of the total water‐soluble carbohydrates in all of the grass species. Fructosans were the predominant carbohydrates.

Carboidratos não estruturais e acúmulo de forragem em pastagens de Cynodon spp. sob lotação contínua

“…Esses açúcares possuem grande importância no metabolismo vegetal devido a participarem ativamente de vias metabólicas como metabólitos intermediários (Stryer, 1975). As gramíneas forrageiras originárias de países de clima tropical e subtropical acumulam principalmente amido, o qual pode ser encontrado nas formas de amilose e amilopectina (Smith & Grotelueschem, 1966). Os CNE são considerados os componentes de reserva mais importantes de gramíneas forrageiras.…”

Failure of cellulolysis in the rumen of reindeer fed timothy silage

“…The distillate was collected in H2S04 and excess acid was titrated with NaOH (Horwitz, 1980). To determine WSC the material was extracted with NaOH (Smith & Grotuleschen, 1966), deproteinsed with zinc sulphide/barium hydroxide, and the WSC content assayed using the ferricyanide method (Furuholmen et al, 1964). The fibre fraction (cellulose, hemicellulose and lignin) was calculated from values of NDF, ADF and ADL by methods of Van Soest (1963 a, b), Van Soest & Wine (1967) and Goering & Van Soest (1970).…”

Variation and Correlations among European and North American Orchardgrass Germplasm for Herbage Yield and Nutritive Value

“…In previous breeding efforts to improve perennial forage grass quality, it was noticed that water-soluble carbohydrate (WSC) accumulation in forage grasses was correlated with abiotic stress tolerance [14][15][16][17][18][19]. The WSC in crown tissues were found to stabilize lipids in cellular membranes [19], prevent membrane leakage, and maintain osmotic potential of the cells under cold and drought stress [17,18,[20][21][22].…”

“…In addition to their role in abiotic stress tolerance, increased WSC in leaf and stem tissue can result in improved protein digestion, decreased nitrogen waste through feces and urine, and increased meat and milk productivity in feeding animals [23]. In orchardgrass, the overwhelming majority of all WSC are fructans [14,24], which bridge the gap between resource availability and demands [17]. Increasing WSC (i.e., fructans) is a tangible method of increasing both abiotic stress tolerance and forage quality in orchardgrass.…”