Carbohydrates contribution

Soil polysaccharides can amount to as much as 20% of the humic fractions isolated in aqueous media, and identification of the classes of components in humin materials in associations with the soil clays indicates that carbohydrates contribute significantly to those isolated in the DMS0/H2S04 medium (see Sections 1.4.7 and... 

Calculated from the amino-acid sequence without carbohydrate contribution. The protein exists as a homodimer in solution. 

Fats, or lipids, provide 9 calories per gram as compared with 4 calories per gram for both carbohydrates and proteins. Like carbohydrates, lipids are made only of carbon, hydrogen, and oxygen. Their main purpose in the body is to act as a backup fuel source. Usually fats provide two-thirds of the body s energy. Carbohydrates contribute the rest. 

Usually, carbohydrates contribute only four Calories per gram as opposed to the nine Calories per gram that come from fats. But cellulose, a carbohydrate in the cell walls of plants, contributes no Calories at all because the body is not able to metabolize it. Avicel is a form of natural cellulose that, when mixed with water, produces a texture similar to fat. It can replace fats in frozen desserts and bakery products. 

The contents of this volume then are dedicated to a better understanding of the ways in which our largest single dietary constituent—the carbohydrates-—contributes to the physical and chemical nature as well as the nutritional quality and acceptability of our foods. 

Polypeptide molecular weights do not include carbohydrate contributions. 

For simplification of the above outlined model approach the concept of active biomass is introduced, where the functional macromolecules are combined to form the active part rx,act md accumulated lipids or carbohydrates contribute to the apparent biomass formation >Xapp- Lipids themselves are part of the cell dry mass but do not contribute to tight capture and do not support the cell machinery directly. This leads to the mass balance, neglecting hydration or de/carboxylation reactions... 

Structural drawings of carbohydrates of this type are called Haworth formulas, after the British chemist Sir Walter Norman Haworth (St Andrew s University and the University of Birmingham) Early m his career Haworth contributed to the discovery that carbohydrates exist as cyclic hemiacetals rather than m open chain forms Later he col laborated on an efficient synthesis of vitamin C from carbohydrate precursors This was the first chemical synthesis of a vitamin and provided an inexpensive route to its prepa ration on a commercial scale Haworth was a corecipient of the Nobel Prize for chem istry m 1937... 

There has been growing activity in the biomodification of existing carbohydrate polymers, and although these types of studies may be too impractical to promote commercial activity in the neat future, they ate contributing to an understanding of stmcture/property relationships in aqueous media (16). 

Soybean concentrate production involves the removal of soluble carbohydrates, peptides, phytates, ash, and substances contributing undesirable flavors from defatted flakes after solvent extraction of the oil. Typical concentrate production processes include moist heat treatment to insolubilize proteins, followed by aqueous extraction of soluble constituents aqueous alcohol extraction and dilute aqueous acid extraction at pH 4.5. 

In the confectionery industry, com symps are used extensively in nearly every type of confection, ranging from hard candy to marshmallows. In hard candies, which are essentially soHd solutions of nearly pure carbohydrates, com symp contributes resistance to heat discoloration, prevents sucrose crystallization, and controls hygroscopicity, viscosity, texture, and sweetness. Maltose symps, high conversion symps, and acid-converted symps (36 and 42 DE) are used for this appHcation. 

Pyruvate ketals add to the anionic nature of the exopolysaccharide and are usually present in stoichiometric ratios with the carbohydrate component Pyruvate is normally attached to the neutral hexoses but may also be attached to uronic adds. In the absence of uronic acids, pyruvate alone contributes to the anionic nature of the exopolysaccharide. 

We will focus on the development of ruthenium-based metathesis precatalysts with enhanced activity and applications to the metathesis of alkenes with nonstandard electronic properties. In the class of molybdenum complexes [7a,g,h] recent research was mainly directed to the development of homochi-ral precatalysts for enantioselective olefin metathesis. This aspect has recently been covered by Schrock and Hoveyda in a short review and will not be discussed here [8h]. In addition, several important special topics have recently been addressed by excellent reviews, e.g., the synthesis of medium-sized rings by RCM [8a], applications of olefin metathesis to carbohydrate chemistry [8b], cross metathesis [8c,d],enyne metathesis [8e,f], ring-rearrangement metathesis [8g], enantioselective metathesis [8h], and applications of metathesis in polymer chemistry (ADMET,ROMP) [8i,j]. Application of olefin metathesis to the total synthesis of complex natural products is covered in the contribution by Mulzer et al. in this volume. 

Chemists tend to be prolific authors. Some say they have a conceit of authorship, whereas others contend it is pride. Stacey was certainly proud of his many scientific papers (more than 350) and several books. In addition, he was founder-editor of three journals and he was a member of the editorial boards of several others. He was a supporter of Advances in Carbohydrate Chemistry from its inception. He served on the advisory board for many years, was associate editor, and contributed to early volumes. 

Besides research already outlined, Stacey undertook other work, some of which was distinct from carbohydrate chemistry. This relates to his contributions to radiation chemistry, analysis, organofluorine chemistry, and soil chemistry. 

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