Lactose natural sources

This particular trimethylglucose is unique in that it was separated in crystalline form from the hydrolyzates of the methyl ethers of several naturally-occurring glucose polymers almost two decades before it was synthesized from glucose. These natural sources, which still furnish the most convenient routes for the preparation of 2,3,6-trimethyl-D-glucose, include maltose,124-128 cellobiose,127,128 lactose,122-181 starch,71,182 glycogen,188,184 cellulose,185-187 and lichenin. 188,189 The literature pub-... 

Dulcitol is no longer obtained in practice from Madagascar manna or other natural sources, but is produced by the catalytic hydrogenation of D-galactose, or, along with sorbitol, of hydrolyzed lactose because of its lower solubility in water it is readily separated from the sorbitol. 

Several solid polyols can be used as direct compression diluents, usually after some physical modification. Most such polyols can be obtained from natural sources, but are usually manufactured by hydrogenation of the parent sugar molecule. Some properties of polyols, together with comparative data for lactose and sucrose, are shown in Table 6. 

Draw the structures of sucrose, lactose, and maltose. Give the natural sources of these common disaccharides. 

Vibrio species are difficult to isolate from natural sources as they tend to be present with coliforms, which outgrow them on many media. Several selective media are available, including DCLS Agar which contains sodium desoxycholate, lactose, sucrose, and the indicator Neutral Red, the desoxycholate suppressing the growth of coliforms. Cholera medium works in a similar manner, in that high levels of ox bile are used to suppress the growth of the normal gut flora. 

State the natural sources of sucrose, maltose, lactose, and starch. 

D (+) Galactose is a constituent of numerous polysaccharides It is best obtained by acid hydrolysis of lactose (milk sugar) a disaccharide of d glucose and d galactose L (—) Galactose also occurs naturally and can be prepared by hydrolysis of flaxseed gum and agar The principal source of d (+) mannose is hydrolysis of the polysaccharide of the ivory nut a large nut like seed obtained from a South American palm... 

In more detail the nutrient medium used may contain sources of carbon such as starch, hydrolyzed starch, sugars such as lactose, maltose, dextrose, sucrose, or sugar sources such as molasses alcohols, such as glycerol and mannitol organic acids, such as citric acid and acetic acid and various natural products which may contain other nutrient materials in addition to carbonaceous substances. 

The method (scheme 1) was targeted to the utilization of readily available carbohydrate sources such as lactose, maltose starch and maltodextrins. It was applicable largely to the preparation of the (S)-acid 1 and the lactone 2 since naturally occurring hexoses have almost exclusively the D-configuration and the C5 carbon becomes the chiral center in the dihydroxy acid. More recently, direct access to the (R)-isomers 4 and 5 was made possible by the development of a similar oxidation method using 5-linked pentoses as the starting compounds... 

With NIR, the source is quite strong, the absorbancies weak, and the detector(s) quite quiet and sensitive. The extra energy can, in some cases, burn the sample. Lactose is an example of a pharmaceutical excipient browned by the energy of FT-NIR. In addition, since most NIR peaks are broad and relatively featureless, high resolution usually adds noise (which is, by nature, high frequency). 

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