Showing papers on "Gum arabic published in 1977"

Fermentation of mucin and plant polysaccharides by strains of Bacteroides from the human colon.

Abstract: Ten Bacteroides species found in the human colon were surveyed for their ability to ferment mucins and plant polysaccharides ("dietary fiber"). A number of strains fermented mucopolysaccharides (heparin, hyaluronate, and chondroitin sulfate) and ovomucoid. Only 3 of the 188 strains tested fermented beef submaxillary mucin, and none fermented porcine gastric mucin. Many of the Bacteroides strains tested were also able to ferment a variety of plant polysaccharides, including amylose, dextran, pectin, gum tragacanth, gum guar, larch arabinogalactan, alginate, and laminarin. Some plant polysaccharides such as gum arabic, gum karaya, gum ghatti and fucoidan, were not utilized by any of the strains tested. The ability to utilize mucins and plant polysaccharides varied considerably among the Bacteroides species tested.

Fermentation of mucins and plant polysaccharides by anaerobic bacteria from the human colon.

Abstract: A total of 154 strains from 22 species of Bifidobacterium, Peptostreptococcus, Lactobacillus, Ruminococcus, Coprococcus, Eubacterium, and Fusobacterium, which are present in high concentrations in the human colon, were surveyed for their ability to ferment 21 different complex carbohydrates. Plant polysaccharides, including amylose, amylopectin, pectin, polygalacturonate, xylan, laminarin, guar gum, locust bean gum, gum ghatti, gum arabic, and gum tragacanth, were fermented by some strains from Bifidobacterium, Peptostreptococcus, Ruminococcus, and Eubacterium species. Porcine gastric mucin, which was fermented by some strains of Ruminococcus torques and Bifidobacterium bifidum, was the only mucin utilized by any of the strains tested.

Fixation of APM in chewing gum

Abstract: This invention relates to a product and process in which L-aspartyl-L-phenylalanine methyl ester is fixed in gum Arabic and/or the reaction product of a compound containing a polyvalent metallic ion, with an ungelatinized starch acid-ester of a substituted dicarboxylic acid whereby the decomposition rate of the L-aspartyl-L-phenylalanine methyl ester when employed in a chewing gum system is greatly reduced.

The effect of viscous substances on the transit time of barley digesta in rats

Abstract: The influence of a number of hydrocolloids on the transit time of digesta, stool weight and colour of stools was investigated in rats. All hydrocolloids tested gave the stools a lighter colour and increased their size and water content. The hydrocolloids could be divided into two groups according to their action on digesta passage: pectin, gum arabic, oxidised starch and barley β-glucan retarded it, while guar gum, carrageenan, tragacanth gum, carob bean gum, sodium alginate and sodium carboxymethyl cellulose accelerated it. After feeding carrageenan for 1 week it took several weeks before water content and transit time returned to normal. Gum arabic was found to cause caecal distension.

Effect of inoculation method on rhizobium survival and plant nodulation under adverse conditions

Abstract: In a series of experiments, different inoculation methods applied to seeds of Glycine wightii were compared for their effect on survival of rhizobia (Rhizobium sp.) under various conditions: high temperature with and without high relative humidity, exposure to sunlight, and contact with superphosphate. Seeds were inoculated with peat inoculum in gum arabic (gum treatment), in gum arabic plus a coating of lime or rock phosphate, or with peat inoculum in water (slurry). When subjected to 50¦C for eight hours a day, survival of the cowpea-type Rhizobium strain CB756 was poorer at 75 per cent relative humidity than at 40 per cent. CB756 survived better than the clover strain TA1 under high temperature and high relative humidity, and neither lime nor phosphate pelleting increased survival of the two strains over the gum treatment. Poorest survival was with phosphate for TA1 and lime for CB756. When exposed to sunlight, numbers of CB756 fell most rapidly in the gum treatment but, after a longer period in a glasshouse at about 30¦C, survival was poorest in the slurry treatment. When mixed with superphosphate, lime pelleting resulted in best survival of both strains. In pot experiments, lime pelleting resulted in a higher percentage of nodulated plants and higher plant weights of Trifolium subterraneum and Glycine wightii, the advantage being greatest when low numbers of rhizobia were on the seed at sowing.

The potentiometric titration of gum karaya aud some other tree-exudate gums

Abstract: Potentiometric titration of gum karaya was used to determine the acid equivalent weight and the proportions of the acid groups in the salt form and the free acid form. Alkaline hydrolysis was used to determine the acyl groups attached to the gum. These determinations were also carried out with other tree-exudate gums including gum arabic, gum jeol (Lannea coromandelica gum) and tree-gums from Sterculia tragacantha, Acacia sieberana, Acacia polyacantha and Albizia zygia. Potentiometric titration also showed the presence of basic groups attached to the polyanion in some gums. The variation of viscosity with pH can be correlated with the potentiometric titration curve.

The Effect of Silicic Acid in the Fountain Solution

Abstract: Silicic acid is a water soluble colloidal resin which can be obtained commercially. The effect of silicic acid as a. desensitizer in fountain solution was studied. The resin of this colloidal solution was compared to gum arabic solution. The study included the investigation of the physical properties of the solution at different concentrations as well as press performance. Comparisons were drawn regarding wettability, viscosity, surface tension, dot size change, minimum dampening rate to clean-up the non-image areas, reso lution, resistance to scum, blinding of image areas, rate of de-inking overrun non-image areas, performance distinction between lithium silicate and sodium silicate, and changes with aging in solubility properties of silicates in fountain solutions. The experiments were carried out under carefully control led conditions; the only variable present was one ingredient of the fountain solution. The concentration of the necessary solution was determined. The effect of concentration was discussed and reported. A considerable number of the results were statistically analyzed by the two factor analysis of variance. The effectiveness of silicic acid solution as a substi tute for gum arabic solution varied. Silicic acid is compar able in regard to the ability of the solution to clean the plate with minimum number of sheets, resistance to scum, reso lution, and blinding of image areas. Performance distinc tions between lithium silicate and sodium silicate and solu bility properties of silicates with aging were noted. Gum arabic produces smaller changes in dot size and does not blind images as quickly as silicic acid does. The advantages of silicic acid are good resistance to bacterial attack, longer shelf life, and better v/etting of the plate than gum arabic when properly diluted. Abstract approved: , thesis advisor , title and department , dateapproved: , thesis advisor , title and department , date