Enzyme endogenous

Historically, dietary fiber referred to iasoluble plant cell wall material, primarily polysaccharides, not digested by the endogenous enzymes of the human digestive tract. This definition has been extended to iaclude other nondigestible polysaccharides, from plants and other sources, that are iacorporated iato processed foods. Cellulose [9004-34-6] (qv) is fibrous however, lignin [9005-53-2] (qv) and many other polysaccharides ia food do not have fiberlike stmctures (see also Carbohydrates). 

In contrast to colorless phenolics, betalains are most soluble in water and are even more hydrophilic than the anthocyanins that readily dissolve in methanol. However, to preclude activities of endogenous enzymes during extraction, aqueous methanol at a ratio of 60 40 or 80 20 (v/v) is recommended. 

Electrolyte leakage due to the action of endogenous enzymes. Extracts from tub ... 

Petkevicius, S., Bach Knudsen, K. E., Nansen, P., Roepstorff, A., Skjoth, F., Jensen, K. and Knudsen, K. E. B. (1997). The impact of diets varying in carbohydrates resistant to endogenous enzymes and lignin on populations of Ascaris suum and Oesophagostomum dentatum in pigs . Parasitology, 114(6), 555-568. 

No antibodies, only application of developer. If positive, this shows endogenous enzyme activity. To solve this, raise levamisol concentration, with 20% acetic acid for 5 min, followed by intensive washing in water prior to the immunoprocedure (14). 

Blocking step 1 to block endogenous enzyme activity or endogenous biotin, use the corresponding blocking system (see Chap. 5) and wash in PBS or TBS for 2x3 min. 

When using high-temperature antigen retrieval, you may skip blocking alkaline phosphatase, since some endogenous enzymes, such as alkaline and acid phosphatases, in contrast to peroxidase, are destroyed by boiling for even a short time at 100°C (Cattoretti et al. 1993). 

Endogenous enzyme blocking solution, 1.5% hydrogen peroxide (H2O2) in PBS prepared from a dilution of 30% H2O2. 

Block endogenous peroxidase and peroxidase-like activity by incubation in 1.5% H2O2 in PBS endogenous enzyme blocking solution for 15 min with constant stirring (see Note 8). 

The enzyme or the chromogen detection system determines whether any endogenous material must first be destroyed. If a peroxidase marker molecule is to be used, endogenous peroxidase or peroxidase-like activity should be blocked. Because these preparations are more fragile than a fixed embedded sample, endogenous enzyme is inactivated with a weaker blocking solution than would... 

Other minor enzyme systems can be used such as betagalactosidase (5). This system works well however, it can lead to some false-positive problems resulting from endogenous enzymes that have a similar reactivity (d). Another enzyme not commonly used is glucose oxidase. A glucose oxidase system... 

There are inherent problems associated with enzyme-mediated methods, regardless of the method used. The right conditions must be met, of course, for the enzyme action to take place. Unlike fluorochromes or gold particles (two other marker compounds), enzymes need to act chemically for the assay to work. Also, the enzyme action must only represent the marker molecule. Endogenous enzyme or enzyme-like activity can create problems only realized in systems that use enzymes. Also, the use of enzymes demands more attention to detail because of the increase in sensitivity that is often obtained. The problem of unwanted reactivity is enhanced in enzyme-mediated reactions more so than in others, in part because of the additional level of sensitivity brought about by the continuous action on a substrate. 

Vidarabine inhibits vitally induced DNA polymerase more strongly than it does the endogenous enzyme. Its use is now limited to topical treatment of severe herpes simplex infection. Before the introduction of the better tolerated acyclovir, vidarabine played a major part in the treatment of herpes simplex encephalitis. 

The availability of endogenous enzymes and their variants has allowed the use of enzymes as replacement therapy and as therapeutic agents. With continued refinement in recombinant protein technology, the cost of human recombinant proteins may become more affordable. As more novel human recombinant enzymes are developed, a wide variety of medical disorders will be amenable to enzyme therapies. Additional molecular engineering such as pegylation or creation and modification of... 

Block the endogenous enzyme with 0.3% H202 for 30 min (alternatively, incubate in 2.3% periodic acid for 5 min, wash with water, rinse in 0.03% potassium borohydride and wash), or incubate for 5 min in 0.1% phenylhydrazine in PBS)... 

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