Pectin suspension

Albert KS, Ayres JW, Di Santo AR, et al. Influence of kaolin-pectin suspension on digoxin bioavailability. J Pharm Sci 1978 67 1582-1586. 

Drug Interactions - Absorption half-life of the antibiotic, clindamycin, was prolonged in human subjects when a kaolin-pectin antidiarrheal suspension was coadministered, although the extent of absorption remained the same. On the other hand, both the rate and the extent of absorption of digoxin were lower when it was coadministered with the same kaolin-pectin suspension. Physical absorption and alterations in gut transit time appeared to partly explain the findings. 

Co-immobilization Pectin, 6 g, was dissolved in 78 ml distilled water, with subsequent addition of 6 ml sodium acetate buffer (1 M, pH 4.2) and 10 g wet yeast. Silica containing immobilized enzyme (206.5 U/g dried silica or 272.2 U/g dried silica) was then mixed with the suspension at the ratio of 1.5 g of wet silica-enzyme/20 g yeast-pectin suspension. One gram of dried silica corresponded to 1.5 of wet silica. Finally, the suspension was dropped in a 0.2 M CaC solution, and 18.5 g of 4 mm spherical particles were formed after curing in a refngerator, for 18 to 20 h. 

Co-trimoxazole suspension (trimethoprim 160 mg with sulfamethoxazole 800 mg) was given to 8 healthy subjects, with and without 20 mL of kaolin-pectin suspension. The kaolin-pectin reduced the AUC and the maximum serum levels of the trimethoprim by about 12% and 20%, respectively. Changes in the sulfamethoxazole pharmacokinetics were not significant. The probable reason for this reduction in AUC is that trimethoprim is adsorbed onto the kaolin-pectin, which reduces the amount available for absorption. However, the reductions are small and unlikely to be clinically relevant. 

Albert KS, Elliott WJ, Abbott RD, Gilbertson TJ, Data JL. Influence of kaolin-pectin suspension on steady-state plasma digoxin levels. J Clin Pharmacol (1981) 21, 449-55. 

The concurrent use of kaolin-pectin suspension and digoxin reduced the peak plasma digoxin levels of 7 patients by 36%, while the AUCq 24 was reduced by 15%. Conversely, when two doses of kaolin-peetin were taken, the first 2 hours before and the other 2 hours after the digoxin, no significant changes were seen. ... 

Our two network model of the primary wall receives support from a variety of indirect observations. For example it has been shown Aat when a cell wall is regenerated by a carrot protoplast a homogalacturonan/ rhamnogalacturonan shell is laid down first, through which the cellulose/ hemicellulose network is later intercalated (8). Further evidence that pectin may form an independent network is seen in the fact that walls from suspension-cultured cells of tofnato Lycopersicon esculentum VF 36),... 

Fig 4 FTIR spectra of walls of DCB-adapted and non-adapted tomato suspension cells, onion parenchyma cell walls, and polygalacturonic acid (Sigma), a = ester peak, b = free acid stretches from pectins, y axis is absorbance, X axis is wavenumber (frequency inverse). 

Doong, R.L., liljebjelke, K., FraUsh, G., Kumar, A., and Mohnen, D. (1995) CeU-free synthesis of pectin Identification and partial characterization of polygalacturonate 4-a-galacturonosyltransferase and its products fix)m membrane preparations of tobacco ceU-suspension cultures. Plant Physiol. 109 141-152. 

Fig. 10. Intercellular junction zones of carrot cells grown in suspension have been observed in electron microscopy after immunogold labeling with the 2F4 antibody, (a) no treatment of the sections prior to labeling the gold particles are restricted to the center of the junction zones (b) enzymatic (pectin methyl esterase) deesterification of the E.M. grids before labeling the deesterified pectins present in the primary walls now bind the probe. Scale bars = 1 pm.

The differentiation of cells occurs concomitantly to modifications of wall components. The nature of the pectins of the walls changes under the action of enzymes, among which esterases, secreted between the apical meristematic cells and the more basal differentiated cells. The apposition of new layers of pectins with different compositions at the inner surface of the walls is another mechanism by which the cells adapt their immediate environment. Using the 2F4 antibody, we have observed, in plant suspensions as well as in tissues, a third mechanism involved in wall modification. Numerous invaginations of the... 

The possibility that the initial degree of methyl-esterification might be controlled by the properties of the methyltransferase enzymes was examined partial characterisation of these enzymes in suspension-cultured cells of fiax. Pectin methyltransferases beii enzymes characteristic of the Golgi apparatus [22], microsomes were fiactionated daily for ten days from suspension-cultured flax cells and incubated in the presence of C-SAM, the universal donor of methyl groups. 

Ultrafiltration of heterogenous colloidal suspensions such as citrus juice is complex and many factors other than molecular weight contribute to fouling and permeation. For example, low MW aroma compounds were unevenly distributed in the permeate and retentate in UF in 500 kd MWCO system (10). The authors observed that the 500 kd MWCO UF removed all suspended solids, including pectin and PE. If PE is complexed to pectate in an inactive complex, then it is conceivable that release of PE from pectin with cations will enhance permeation in UF. At optimum salt concentration, less PE activation was observed at lower pH values than at higher pH (15). In juice systems, it is difficult to separate the effect of juice particulates on PE activity. Model studies with PE extracts allows UF in the absence of large or insoluble particulates and control of composition of the ultrafilter. In... 

PECTIN METHYLTRANSFERASES FROM SUSPENSION-CULTURED CELLS AND SEEDLINGS OF FLAX Linunt mitatissimum L. ). 

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