Sugar, complex simple

The glycolytic pathway described in this chapter begins with the breakdown of glucose, but other sugars, both simple and complex, can enter the cycle if they can be converted by appropriate enzymes to one of the intermediates of glycolysis. Figure 19.32 shows the mechanisms by which several simple metabolites can enter the glycolytic pathway. Fructose, for example, which is pro-... 

The literature on metal complexes of carbohydrates through 1965 has been fully reviewed by Rendleman (I), and we shall therefore only discuss recent work. We shall not discuss the complexes formed with strong bases, such as calcium and barium oxide these are salts in which the sugar acts as a weak acid, losing one or several protons. Nor shall we discuss the complexes formed with anions of oxyacids—e.g., borate, stannate, periodate, etc. ions all these are compounds formed by covalent bonds in alkaline solution. We are concerned only with complexes formed with cations in neutral aqueous solution there is no evidence for the formation of complexes between sugars and simple anions in neutral aqueous solution. (For an example of complex formation between a sugar derivative and chloride ion in chloroform solution, see Reference 3.)... 

The aminopropylsilyl guard column is required for complex matrices with low sugar content. Simple matrices with high sugar content do not require the guard column. Other parameters may need adjustment in order to optimize the chromatography. 

Carbohydrates are classified as either simple or complex. Simple sugars, or monosaccharides, are carbohydrates such as glucose and fructose that can t be broken down into smaller molecules by hydrolysis with aqueous acid. Complex carbohydrates, or polysaccharides, are compounds such as cellulose and starch that are made of many simple sugars linked together. On hydrolysis, polysaccharides are cleaved to yield many molecules of simple sugars. 

Digestion starts in the mouth, where saliva breaks down starch (a complex carbohydrate) into sugar (a simple one). This is why chewing on a piece of bread for a long time makes it start to taste... 

Dietary carbohydrates are often classified as simple or complex. Simple carbohydrates are the sugars we classified earlier as monosaccharides and disaccharides (Chapter 7). Complex carbohydrates consist essentially of the polysaccharides amylose and amylo-pectin, which are collectively called starch. Cellnlose, another polysaccharide, is also a complex carbohydrate however, becanse it cannot be digested by hnmans, it serves a non-nntritive role as fiber. 

If our food was a dietetic beverage (almost a pure aqueous solution), we could readily predict kg, for an aroma compound (and therefore recovery during isolation). Unfortunately, the presence of various solutes in the food (simple sugars, complex carbohydrates, lipids, proteins, water, minerals, etc.) enormously complicates this equation and our task.. Some factors can be predicted and thus understood, for example, lipid effects. Others, for example binding by proteins or salting out by simple sugars, are not predictable and thus cannot currently be accounted for in a theoretical treatment. 

Simple carbohydrates are monosaccharides (single sugars) complex carbohydrates... 

Polysaccharides, Polysaccharides are large sugar complexes that contain repeating sequences of simple sugars— chains of monosaccharides. In plants and animals they are used either for carbohydrate storage or structural support... 

Free Sugars and Simple Derivatives Thereof.- The inclusion complex of (R)-phenylethylamine with 2,3.4,6-tetra-O-acetyl-D-glucose. ... 

The phosphitylation of D-mannose with phosphorous triazolides has afforded primarily the mannofuranose 2,3,6-O-phosphite 12. The complexes formed separately between o-fructose and L-sorbose with 1,10-phenanthroline and Co(III) ions have been characterised, while composites prepared by the reaction of simple sugars with tetraethoxysilane and water have been shown to be capable of resolving racemic cobalt and chromium ion complexes. Sodium alkoxide salts of free sugars have been treated with ferric chloride to give iron-sugar complexes and five-fold deprotonated D-mannose forms dinuclear metalates [X2(P-D-Man-/)2] of trivalent (X = Fe, V, Cr and Al) with O-1,2,3,5 and 6 involved in complexation. ... 

As a group, the MlC-causing bacteria may use almost any available organic carbon molecules, from simple alcohols or sugars to phenols to wood or various other complex pcJymers as food (heterotrophs), or they may fix CO9 (autotropha) as do plants. Some use inorganic elements or ions (e.g., NH or NO, CH, H, S, Fe, Mu, etc.), as sources of... 

Simple sugars undergo reaction with phenylhydrazine, PhNHNH2, to yield crystalline derivatives called osazones. The reaction is a bit complex, however, as shown by the fact that glucose and fructose yield the same osazone. 

Carbohydrate (Section 25.1) A polyhydroxy aldehyde or ketone. Carbohydrates can be either simple sugars, such as glucose, or complex sugars, such as cellulose. 

Complex carbohydrate (Section 25.1) A carbohydrate that is made of two or more simple sugars linked together. 

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