The objective of the present work was extraction of polysaccharide from Senna tora L. seed and its characterization as a pharmaceutical excipient. Polysaccharide extraction was based on mechanical separation of the endosperm of seeds of Senna tora, water dissolution, centrifugation, and precipitation with acetone. Standard procedures were used to study the viscosity, micromeritic properties, an...

Catalytic activity of the filamentous polymeric form of avian liver acetyl-CoA carboxylase, (spO+ = 45 to 47 S) undergoes first-order decay in assay reaction mixture (f; 10 min at Z”), which is rapidly reversed ( <lO s) by addition of tricarboxylic acid activator, i.e. citrate or isocitrate. As previously shown by sucrose density gradient centrifugation, extended exposure to assay reaction mixt...

In order to simulate the in vivo dissolution of drugs, biorelevant dissolution media (BDM), simulating the gastric or intestinal juices are often employed. For gastric BDM, pH, surface tension and osmolality is simulated, however, viscosity has, to our knowledge not been taken into account. The dissolution rate of a drug compound is influenced by the viscosity of the dissolution medium. In the ...

The dependence of the intrinsic viscosity [η] on the weight average degree of polymerization Pw of chitosans in aqueous acid media is discussed in terms of the Yamakawa-Fujii theory for the worm-like cylinder model. The conformational characteristics (Kuhn statistical segment length and Flory characteristic ratio) are estimated. They increase linearly with the reciprocal of the square root of s...

A non-Brownian suspension of micron scale rods exhibits reversible shear-driven formation of disordered aggregates resulting in dramatic viscosity enhancement at low shear rates. Aggregate formation is imaged using a combined rheometer and fluorescence microscope. The size and structure of these aggregates are found to be a function of shear rate and concentration, with larger aggregates presen...

Keloids are exuberant scars, in which collagen, fibronectin and glycosaminoglycans are overdeposited. Biochemical analysis of the collagen isolated from normal skin and keloid tissue by pepsin treatment, indicated an increase in the type III and GAG content. Viscosity measurements of collagen from normal skin and keloid tissue were used in the present study to establish the interaction between ...

Visually identifying and estimating properties of materials is critical for many tasks, from reaching for a steaming kettle to walking on a wet marble staircase. From a computational point of view, liquids represent a particularly interesting class of materials because of their highly mutable shapes and physical complexity. The ways liquids move and change shape is affected both by external for...

Partial periodate oxidation of hyaluronan (HA) leads to ring opening of the 4-linked D-glucuronate (GlcA) residues, providing a particularly flexible element within otherwise semi-flexible chains. This leads to compaction of the chains as demonstrated by a pronounced decrease in the intrinsic persistence length, which was determined on the basis of the molecular weight dependence of radius of g...

Lundgren, D. G. (Syracuse University, Syracuse, N.Y.), R. Alper, C. Schnaitman and R. H. Marchessault. Characterization of poly-beta-hydroxybutyrate extracted from different bacteria. J. Bacteriol. 89:245-251. 1965.-Poly-beta-hydroxybutyrate (PHB) from different bacterial genera was studied with regard to its crystal structure, infrared absorption, intrinsic viscosity, and electron microscopy. ...