Biopolymers functionalization

Tolstoguzov, V. (2002). Thermodynamic aspects of biopolymer functionality in biological systems, foods, and beverages. Critical Reviews in Biotechnology, 22, 89-174. 

However, before we start om story, there is one more thing to say The main biopolymers function in the medium of water. A human body consists of 60% water by mass some animals carry around even more water in their bodies. Water reservoirs are a source of life (as we shall discuss in more detail in Chapter 14). Therefore, it might be helpful to learn a bit about... 

The enzymatic tools for functionalization of chitin/chitosan are selected on the basis of the chemical structure of these biopolymers (functional groups and targeted enzyme activities related) and include oxidases, e.g., tyrosinase, peroxidase, laccase and transferase (transglutaminase) types of enzymes. The same enzymatically assisted reactions could be further employed to crosslink the functionalized biomaterials in order to improve their exploitation characteristics, i.e., stability at use. 

Proteins are biopolymers formed by one or more continuous chains of covalently linked amino acids. Hydrogen bonds between non-adjacent amino acids stabilize the so-called elements of secondary structure, a-helices and / —sheets. A number of secondary structure elements then assemble to form a compact unit with a specific fold, a so-called domain. Experience has shown that a number of folds seem to be preferred, maybe because they are especially suited to perform biological protein function. A complete protein may consist of one or more domains. 

In this section we briefly consider the osmotic pressure of polymers which carry an electric charge in solution. These include synthetic polymers with ionizable functional groups such as -NH2 and -COOH, as well as biopolymers such as proteins and nucleic acids. In this discussion we shall restrict our consideration... 

Two-dimensional nmr spectroscopy has led to a much better understanding of biopolymers and their function (151). This technique has been apphed to polyacrylamide for absolute assignments of proton and carbon spectra at the tetrad level (152). 

Synthesis of reactive nucleic acids derivatives and their use for investigations of structure and functions of biopolymers 98UK688. 

The biological function of biopolymers such as polypeptides, proteins, nucleic acids etc. depends strongly on their ordered structure which is determined by the pattern of inter- and intramolecular interactions given by the primary structure. 

Fig. 7. Besides direct interactions between functional groups of the biopolymer molecule itself there are also various kinds of interactions with water molecules. These hydrophilic and hydrophobic interactions are essential for stabilizing the native conformation of biopolymers. In the last few years some progress was made in elucidating the hydration of these molecules.

The consideration made above allows us to predict good chromatographic properties of the bonded phases composed of the adsorbed macromolecules. On the one hand, steric repulsion of the macromolecular solute by the loops and tails of the modifying polymer ensures the suppressed nonspecific adsorptivity of a carrier. On the other hand, the extended structure of the bonded phase may improve the adaptivity of the grafted functions and facilitate thereby the complex formation between the adsorbent and solute. The examples listed below illustrate the applicability of the composite sorbents to the different modes of liquid chromatography of biopolymers. 

The chitin is modified to impart the structure required by the functions of each particular tissue, via crystalHzation, deacetylation, cross-finking to other biopolymers (Fig. 1), and, in certain cases, quinone tanning. The resulting complex structures are capable of exceptional performances [15]. 

In summary, besides its use as texturing additive, the combined functionality of GA is an advantage over other edible biopolymers that do not show antioxidant activities... 

The ionic strength dependence of intrinsic viscosity is function of molecular structure and protein folding, ft is well known that the conformational and rheological properties of charged biopolymer solutions are dependent not only upon electrostatic interactions between macromolecules but also upon interactions between biopolymer chains and mobile ions. Due electrostatic interactions the specific viscosity of extremely dilute solutions seems to increase infinitely with decreasing ionic concentration. Variations of the intrinsic viscosity of a charged polyampholite with ionic strength have problems of characterization. 

Deoxyribonucleic acid (DNA) is a very important biopolymer with the function of storage and transmission of genetic information. In this reason the protection of structural integrity and functional activity of DNA is essential for the viability of living systems, as well as the effectiveness of laboratory DNA-technics. 

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