the conversion of the cellulose into 5-hmf would experience three steps, cellulose to glycose, glycose to fructose and fructose to 5-hmf. chloride ion can break down the hydrogen bond in cellucose, chromium can catalyze the isomerization of glycose to fructose, and the high temperature is helpful to cyclohydration of fructose to 5-hmf. in this paper, the sawdust has been directly degraded into ...

Fructose raises blood glucose and lactate levels in normal as well as diabetic man, but the tissue origin (liver and/or kidney) of these responses and the role of insulin in determining the end products of fructose metabolism have not been fully established. Splanchnic and renal substrate exchange was therefore examined during intravenous infusion of fructose or saline in six insulin-deficient ...

1. In the hypodermis and gill of the Crustacea fructose 1,6-diphosphatase (EC 3.1.3.11) functions at a primary branch point between glycogen and chitin synthesis. In these tissues of the Arctic king-crab, Paralithodes camtchatica, fructose diphosphatase occurs in two electrophoretically distinguishable forms. 2. Fructose diphosphatase I (pI7.2-7.5) accounts for 70 and 10% of total fructose diph...

Oscillatory behavior of glycolysis in cell-free extracts of rat skeletal muscle involves bursts of phosphofructokinase activity due to autocatalytic activation by fructose-1,6-P2. Fructose-2,6-P2 is an even more potent activator of phosphofructokinase and is competitive with fructose-1,6-P2 in binding and kinetic studies. The possible role and effects of fructose-2,6-P2 on the oscillating syste...

A thiol group present in rabbit liver fructose-1,6-bisphosphatase is capable of reacting rapidly with N-ethylmaleimide (NEM) with a stoichiometry of one per monomer. Either fructose 1,6-bisphosphate or fructose 2,6-bisphosphate at 500 microM protected against the loss of fructose 2,6-bisphosphate inhibition potential when fructose-1,6-bisphosphatase was treated with NEM in the presence of AMP f...

Chicken liver fructose diphosphatase has been prepared in a homogeneous form. The molecular weights of the enzyme and the dissociated enzyme were determined to be 142,000 and 38,000, respectively, by a high speed sedimentation equilibrium technique and by acrylamide gel electrophoresis in sodium dodecyl sulfate. The effect of fructose diphosphatase on phosphofructokinase was investigated using ...

Subjects with obesity frequently have elevated serum vasopressin levels, noted by measuring the stable analog, copeptin. Vasopressin acts primarily to reabsorb water via urinary concentration. However, fat is also a source of metabolic water, raising possibility that might role in accumulation. Fructose has been reported stimulate vasopressin. Here, we tested hypothesis fructose-induced syndrom...

Previous studies showed that Arthrobacter pyridinolis can transport and utilize d-glucose only after prior growth on certain Krebs cycle intermediates. In contrast, we found that d-fructose was taken up and metabolized by A. pyridinolis without special prior conditions of growth. d-Fructose was first converted to d-fructose-1-phosphate by a phosphoenolpyruvate (PEP):D-fructose phosphotransferas...

Metabolic studies suggest that the absorptive capacity of the small intestine for fructose is limited, though the molecular mechanisms controlling this process remain unknown. Here we demonstrate that thioredoxin-interacting protein (Txnip), which regulates glucose homeostasis in mammals, binds to fructose transporters and promotes fructose absorption by the small intestine. Deletion of Txnip i...

Concern exists that increasing fructose consumption, particularly in the form of high-fructose corn syrup, is resulting in increasing rates of fructose intolerance and aggravation of clinical symptoms in individuals with irritable bowel syndrome. Most clinical trials designed to test this hypothesis have used pure fructose, a form not commonly found in the food supply, often in quantities and c...