Carbohydrate fermentation lactose

The presence of unusual carbohydrate fermentation patterns (particularly for lactose), and the ability to use citrate among Enterobacteriaceae has hindered, and sometimes jeopardized, the identification of pathogenic strains including Salmonella typhi. 

Carbohydrates are also precursors of carboxylic adds. Bacteria of the genera Clostridium, Butyribacterium and Butyrmbrio ferment sugars primarily to acetic and butyric acids. Bacteria of the genus Propionibacterium (P. freudenreichii subsp. shermanii) ferment lactose to lactic acid, which is reduced to propionic acid, an important add of the most famous Swiss cheese, Emmental (Figure 8.39). The first step of this biosynthesis is the reaction of... 

Fermented carbohydrates Galactose, lactose, glucose, fructose, mannose, sucrose, maltose, trehalose, starch (Table 8) ... 

Uses of lactose production by appHcation include baby and infant formulations (30%), human food (30%), pharmaceuticals (25%), and fermentation and animal feed (15%) (39). It is used as a diluent in tablets and capsules to correct the balance between carbohydrate and proteins in cow-milk-based breast milk replacers, and to increase osmotic property or viscosity without adding excessive sweetness. It has also been used as a carrier for flavorings. 

A typical fermentation medium for penicillin production contains lactose, com steep Hquot, and calcium carbonate (3,153,154). In most industrial processes the carbohydrate source, glucose, beet molasses, or lactose, is continuously added to the fermentation. The rate of glucose addition must be carefully monitored, by pH or rate of oxygen depletion, because the synthesis of penicillin is markedly reduced in the presence of excess glucose. 

The contents of the rumen pass steadily into the third chamber of the ruminant stomach , the omasum, where the fatty acids, together with water and salts, are absorbed. These fatty acids provide much of the energy for the ruminant but a price is paid virtually all the carbohydrate in the diet is fermented and almost none enters the body. Consequently, glucose must be synthesised to provide lactose in the lactating animals. The lactic and propionic acids are the precursors for the glucose (Chapter 6). It is unclear if some of this glucose is used by the brain of the ruminant. 

In ruminants, lactic and propionic acids are the major precursors of glucose. This is particularly important during lactation, since all the carbohydrate in die food is fermented by die bacteria in the rumen, so diat no glucose enters the body but glucose is required for die formation of lactose for the milk (Chapter 6). 

The immediate cause of the ropy or slimy condition is the bacterial formation of gums or mucins by bacteria. Gums are the more common cause. These are probably galactans produced by fermentation of lactose. Some of the active peptonizing bacteria produce sliminess by formation of mucins, which are combinations of proteins with a carbohydrate radical. Development of sliminess is closely associated with capsule formation (Hammer 1930). 

Lactose - [CARBOHYDRATES] (Vol 4) - [COLORANTS FORFOOD, DRUGS, COSMETICS AND MEDICALDEVICES] (Vol 6) - [FERMENTATION] (Vol 10) -with chlorates [CHLORINE OXYGEN ACIDS AND SALTS - CHLORIC ACID AND CHLORATES] (Vol 5) -in fruit juices [FRUITJUICES] (Vol 11) -in milk [MILKANDMILKPRODUCTS] (Vol 16) -pharmaceutical diluents [PHARMACEUTICALS] (Vol 18) -in whey pAIRY SUBSTITUTES] (Vol 7)... 

Lactose [63-42-3] - [CARBOHYDRATES] (Vol 4) - [MILKANDMILKPRODUCTS] (Vol 16) - [FEEDS AND FEED ADDITIVES - RUMINANT FEEDS] (Vol 10) - [SUGAR- SPECIAL SUGARS] (Vol 23) - [FINECHEMICALS - STANDARDS] (Vol 10) -compared to suaose [SUGAR - PROPERTIES OF SUCROSE] (Vol 23) -enzymatic degradation [ENZYME APPLICATIONS - THERAPEUTIC] (Vol 9) -use in antibiotic fermentation [ANTIBIOTICS - BETA-LACTAMS - CEPHALOSPORINS] (Vol 3)... 

Lactic acid is prepared by the fermentation of carbohydrates, such as glucose, sucrose, and lactose, with Bacillus acidi lacti or related microorganisms. On a commercial scale, whey, corn starch, potatoes, or molasses are used as a source of carbohydrate. Lactic acid may also be prepared synthetically by the reaction between acetaldehyde and carbon monoxide at 130-200°C under high pressure, or by the hydrolysis of hexoses with sodium hydroxide. 

In a broad sense, fermentation can be defined by all chemical transformations brought about by living microorganisms, starting with carbohydrates and some N, P, S and other nutritients as feedstock. World-wide use of carbohydrates for fermentation is about 30 million tons/year, of which 20 million is sucrose, the remainder glucose, lactose and starch. 

Most of the lactose in milk is lost in the whey during cheese manufacture and hence most cheese contain only trace amounts of carbohydrate (Table XIII). Furthermore, the residual lactose in cheese curd is usually fermented to lactic acid by starter bacteria. Thus, cheeses are suitable dairy foods for lactose-malabsorbing individuals who are deficient in the intestinal enzyme, lactase. 

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