Previous comparative studies of green, albino, and variegated plants have shown higher levels of soluble nitrogenous compounds and lower levels of protein nitrogen in albino or in variegated than in green tissues (6, 14). The soluble nitrogen level was reduced and the protein level was increased when carbohydrates were supplied to albino tissues and plants. Groner (6), on the basis of such find...

An experiment was conducted to examine the effect that various isoenergetic diets, containing different quantities of soluble carbohydrate and fiber and different types of starch, have on nitrogen (N) balances. Six lactating dairy cows in early to midlactation consuming grass silage diets with not less than 600 g/kg total DMI as forage were used in the experiment. Four concentrates were prepare...

BACKGROUND Although there are several published estimates of the endogenous amino acid composition of ileal digesta in humans, to our knowledge, there are no systematic studies of ileal digesta endogenous proteins. OBJECTIVES We determined the nature and composition of endogenous nitrogen-containing substances lost from the upper digestive tract of humans. DESIGN Digesta were collected from...

It is widely held that herbivore growth and production is limited by dietary nitrogen (N) that in turn constrains ecosystem elemental cycling. Yet, emerging evidence suggests that this conception of limitation may be incomplete, because chronic predation risk heightens herbivore metabolic rate and shifts demand from N-rich proteins to soluble carbohydrate-carbon (C). Because soluble C can be li...

Removal of nitrogen and phosphorus is known to be somewhat problematic in vertical subsurface flow (VSSF)constructed wetlands. In this pilot-scale study, two planted (Typha latifolia L. [cattail]) VSSF-constructed wetlands A (with polypropylene pellets) and B (without polypropylene pellets) and one unplanted control C (without polypropylene pellets) were designed to test the contribution of pol...

The methanogenic archaeon Methanosarcina mazei strain Gö1 uses versatile carbon sources and is able to fix molecular nitrogen with methanol as carbon and energy sources. Here, we demonstrate that when growing on trimethylamine (TMA), nitrogen fixation does not occur, indicating that ammonium released during TMA degradation is sufficient to serve as a nitrogen source and represses nif gene induc...