Freeze denaturation cryoprotective effect

T. Tanaka, T. Takeda, and R. Miyajama, Cryoprotective effect of saccharides on denaturation of catalase during freeze-drying. Chem. Pharm. Bull. 59.-1091-1094 (1991). 

Other Proteins. Since Reay and Dyer discovered that denaturation of myofibrillar proteins is of such profound importance, little attention has been given to the water-soluble proteins including enzymes and other proteins in the sarcoplasm, subcellular organelles, and cell membranes. Recently reports have appeared on the freeze denaturation of enzymes. These studies involved enzymes such as catalase, ADH, GDH, LDH, and MDH from sources other than fish (88,89,90) and attention was given to the effectiveness of various cryoprotective substances (89, 90). Comparable studies with enzymes from fish muscle are few in number (91). Studies on fish muscle proteins must be extended to this area if a complete picture of the freeze denaturation of fish muscle is to be obtained. It should be noted that freeze stable enzymes might have important effects during frozen storage of fish (92,93). 

Controlling freeze denaturation, which appeared very difficult only a short time ago, is now within reach as far as minced muscle is concerned. MSG has proved to be an especially effective cryoprotective agent. Still to be accomplished is the control of protein denaturation in intact fish muscle. 

Four chiral cryptands, derived form D-glucose, D-galactose, D-mannose, and L-tartaric add, have been prepared by short reaction sequences by application of a new, high pressure method. The cryoprotective effect of mannitol, sorbitol, glucose, maltoologosaccharides, and dextran on the denaturation of catalase during freeze-drying has been attributed to the replacement of lost water of hydration by monomolecular saccharide layers. ... 

The cryoprotective effects of glucose, mannitol, glucitol, dextran and malto-oligosaccharides on the denaturation of catalase on freeze-drying has been found to be due to binding of a monomolecular layer of saccharide replacing water of hydration. ... 

A review of the possible quantitative detection of mannitol by chelation with transition metal ions is mentioned in Chapter 17, the conformation of alditols in aqueous and non-aqueous solution is reported in Chapter 21, the cryoprotective effect of mannitol and D-glucitol on the denaturation of the enzyme catalase during the freeze drying process is covered in Chapter 2, the separation of alditols by ion exchange chromatography is mentioned in Chapter 23 and the isolation from two new Streptomyces strains of some secondary metabolites of L-rhodanose is covered in... 

As with fish surimi, the functionality of the material was reduced by freezing and prolonged frozen storage. Under these conditions, the myofibrillar proteins were denatured and the gel strength of the material decreased with storage time. This denaturation was slowed by the addition of cryoprotectants. The most effective cryoprotectant found for beef... 

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