Preservatives proteolytic enzymes

Dialysis tubing is treated with glycerol and preservatives that need to be removed prior to use. Handle the membrane with gloves to avoid introduction of proteolytic enzymes and to reduce punctures. 

Although many proteolytic enzymes are known to exist, we are just beginning to understand how they operate to govern the levels and types of proteins within cells—to distinguish those proteins that must be degraded from those that must be preserved. 

Composition and Methods of Manufacture. The vaccine consists of a mixture of purified capsular polysaccharides from 23 pneumococcal types that are responsible for over 90% of the serious pneumococcal disease in the world (47,48). Each of the polysaccharide types is produced separately and treated to remove impurities. The latter is commonly achieved by alcohol fractionation, centrifugation, treatment with cationic detergents, proteolytic enzymes, nucleases or activated charcoal, diaffltration, and lyophilization (49,50). The vaccine contains 25 micrograms of each of the types of polysaccharide and a preservative such as phenol or thimerosal. 

A mixture of protease inhibitors, which is used to preserve protein integrity during the processing of samples for subsequent analysis. The term cocktail refers to a mixture of components. A protease inhibitor cocktail is composed of a broad spectrum of protease inhibitors and intends to inhibit the diverse proteolytic enzymes found in tissue extracts and biological fluids. See Pringle, J.R., Methods for avoiding proteolytic artifacts in studies with enzymes and other proteins from yeasts. Methods Cell Biol. 12, 149-184, 1975 Dmbin, D.G., Miller, K.G., and Botstein, D., Yeast... 

Dissection of Multifunctional Molecules. Protein molecules generally have more than one antigenic site and occasionally more than one distinctly diflFerent biologically active site. Whenever these sites are discretely separated spatially and are joined by only one or a few interconnecting peptide chains, proteolytic enzymes may separate the sites whil preserving biological activities. Proteolytic scission is most successful when the molecule is elongated or composed of more than one polypeptide chain. 

Hefanol. — N. Iwanoff has studied the proteolytic enzymes of hefanol, which is a commerd2il product, consisting of dead yeast with its enzymes preserved It contains about 9.10 per cent total nitrogen and 6 3 per cent albumin nitrogen. Macerated for a half-hour with 10 volumes of water, it gives a liquid... 

Jensenin P is a bacteriocin produced by P. jensenii B1264- which inhibits closely related propionibacteria and lactic acid bacteria. It was shown that jensenin P is a new anionic bacteriocin (Ratnam et al., 1998). Jensenin P is stable at lOOT for 45 min, at pH 2 to 10 for 225 min, and in 0.1 to 0.3M NaCl (pH 10) for 225 min (Barefoot et al., 1995). The resistance of jensenins to the extremes of pH and high temperature, their wide inhibitory spectrum allows to consider them as useful natural preservatives in thermal food processing. P. jensenii strain DFl was found (Miesher et al., 1998) to markedly inhibit other P. jensenii strains and to suppress 15 out of 24 yeasts and 3 out of 4 molds tested. From the culture broth of P. jensenii DFl an inhibitory protein substance, named SMI, was isolated and partially purified (Miesher et al., 1998). Crude propionicin SMI was sensitive to proteolytic enzymes and stable to incubation at 30°C (more than 14 days), cold storage (more than 6 months at 4 C) and heat treatment (15 min, 100 C). 

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