Abstract: Increased xanthan concentrations are obtained in Xanthomonas fermentations by the gradual addition of a source of assimilable carbon, preferably glucose, to the aqueous nitrient medium during the course of the fermentation cycle.

Abstract: A process for producing heteropolysaccharide S-119 by bacterial fermentation of an organism deposited with the American Type Culture Collection under Accession No. ATCC 31643.

Abstract: A novel process is described for making a low calcium xanthan gum exhibiting smooth flow properties which comprises the use of high levels of phosphate in the fermentation medium.

Abstract: A multi-stage continuous system for producing heteropolysaccharides. The system comprises: a fermentation stage consisting of an outer enzyme/nutrient containing chamber in which a membrane microbial growth chamber is movably mounted, the growth chamber being arranged to continuously produce Xanthomonas campestris cells in the late exponential-early stationary phase of growth and transfer polymerizing exo-enzymes and cell lysate therefrom into the surrounding medium of the enzyme/nutrient chamber and to retain the Xanthomonas campestris cells; and a polymerization state consisting of at least one module to receive the exo-enzymes and cell lysate from the fermentation stage to produce heteropolysaccharides.

Abstract: A high-viscosity heteropolysaccharide composed of 33% mannose, 29% glucose, 21% galactose and 17% glucuronic acid, and containing 5.7% acetyl and 4.9% pyruvate.

Abstract: Xanthan gum is produced by fermentation with the bacterium, Xanthomonas campestris NRRL B-1459, of a nutrient medium containing a sugar and a stimulatory organic acid which stimulates the production of xanthan gum. The stimulatory organic acid can be a source of pyruvic acid, alpha-keto-glutaric acid, succinic acid or mixtures thereof.

Abstract: A fermentation process for the production of microbial biomass and a heteropolysaccharide biopolymer using methane as a carbon source. The biomass is suitable for use as a feedstuff and the polymer can be used as a thickening agent e.g. in foods or in the oil industry for use in drilling muds and to assist the recovery of subterranean deposits of oil. The process comprises cultivating at least one strain of a methane utilizing and extracellular heteropolysaccharide biopolymer forming bacterium of the group Methylomonas in a broth comprising an aqueous nutrient medium and a utilizable nitrogen source in the presence of a gas containing methane as a carbon source and a gas containing free oxygen and recovering biomass and heteropolysaccharide biopolymer from the cultivated broth.

Abstract: Filterability of aqueous solutions of polymers employed to thicken waterfloods such as biopolymers (e.g. heteropolysaccharides) is improved by addition of a surfactant (e.g. a sulfated alkoxylated alcohol). Filterability is further enhanced by addition of an ethoxylated alcohol surfactant and/or an alcohol.

Abstract: A high-viscosity heteropolysaccharide composed of 33% mannose, 29% glucose, 21% galactose and 17% glucuronic acid, and containing 5.7% acetyl and 4.9% pyruvate.

Abstract: A process for producing a heteropolysaccharide by a bacterial fermentation procedure in which a species of bacteria or a mutant thereof is incubated in a fermentation medium which contains a carbon source, preferably a hydrolyxed starch, a source of magnesium ions, a source of phosphorous, a source of nitrogen and water with the incubation taking place at a temperature of about 28.degree. to about 35.degree. C.

Abstract: A process for producing modified heteropolysaccharides derived from a bacteria of the genus Xanthomonas, comprising the steps: (a) preparing an aqueous solution which contains (i) from about 200 to about 30,000 parts per million, by weight of an impure and unmodified heteropolysaccharide product and (ii) at least about 0.5 weight percent of at least one salt to obtain a saline heteropolysaccharide solution; (b) heating said saline heteropolysaccharide solution to a temperature of at least about 100.degree. C.; (c) maintaining said saline heteropolysaccharide solution at a temperature of at least about 100.degree. C.