Inactivation enzymes and

For juice, puree, and paste, the tomatoes are crushed, heated to inactivate enzymes, and pumped through a finisher where the juice is separated from the pulp. The pulp is fed to animals. The juice is canned and is also evaporated to make purde and paste. 

The juice is recovered by inserting tubular knives into the fruit and squeezing the fruit. Alternatively, the fruit may be cut in half and squeezed. The recovered juice is put through a finisher to remove a portion of the pulp sacs, is heated to inactivate enzymes, and is either bottled as single-strength juice or concentrated for frozen concentrate. 

Some of the more thorough studies of orange juice volatile composition were carried out by Schreier et al. [20], Duerr and Schobinger [21] and Nisperos-Carriedo and Shaw [22]. For example, Schreier et al. peeled the oranges before extraction in methanol to inactivate enzymes and prevent contamination from peel oil. Volatiles were separated from the aqueous juice using solvent extraction and were subsequently concentrated. Internal standards were employed to compensate for changes in concentration due to extraction/concentration or variation in sample introduction. Few subsequent studies prepared and analysed juice samples as thoroughly. 

Multifect GC from Genencor, Rochester, NY. The enzyme solutions were characterized by the following activities endo-l,4-(3-xylanase, (3-xylosidase, acetylesterase, a-L-arabinofuranosidase, and filter paper activity (FPase, which describes the overall cellulolytic activity). The dilutions were calculated to provide 100 U of xylanase/g of total xylose in the reaction medium. Hydrolysis reactions were stopped by boiling for 5 min to inactivate enzymes and clarified by centrifugation prior to analysis. A blank OCL sample was assayed identically to enzyme-treated OCL using water instead of the enzyme solution. Control experiments were carried out for each enzyme, in which buffer replaced the OCL. All the hydrolysis trials were performed in duplicate. 

Inhibitors of Enkephalin-Inactivating Enzymes and Delta Opioid Responses... 

The overpressure only inhibits fermentation by yeasts, but does not inactivate enzymes and other microorganisms. These can cause changes in the colour, odour and taste of the juice. 

Toxic potential remains to be established. Resistance has been reported via the formation of inactivating enzymes and t efflux mechanisms. 

Many of the quinone-based mediators react in their reduced states with molecular oxygen. This aerobic regeneration has the advantage that no additional electrochemical equipment is necessary to perform NAD(P)+ regeneration. On the other hand, reactive oxygen species are generated, which might inactivate enzymes and which therefore need to be removed from the reaction mixture. 

Mitsuhashi, S in Drug-Inactivating Enzymes and Antibiotic Resistance, Mitsuhasi, S., Rosival, L., Kromery, V., Eds., Springer Verlag, Berlin, 1975, p. 1175. 

Raw soy sauce may be adjusted to standard salt and nitrogen concentrations. It is then pasteurized at 70—80°C to inactivate enzymes and microorganisms, enhance the unique product aroma, darken color, and induce formation of floes, which facilitates clarification. After heating, the soy sauce is clarified by either sedimentation or filtration. Kaolin, diatomite, or alum may be added before filtration to enhance clarification. The clear supernatant is packed immediately into cans or bottles. In some cases, preservatives, such as sodium benzoate and paraoxy-benzoate, may be used. 

Drug-inactivating enzymes and antibiotic resistance 2nd Intern. Symp. Antibiotic Resistance Castle of Smolenice, Czechoslovakia 1974. Mitsuhashi, S., RosivaJ, L., Krcinery, V. (eds.) pp. 103-192... 

Manothermosonication (MTS), a combined treatment of heat and nltrasonnd nnder moderate pressure, is another alternative to conventional heat treatment in order to inactivate enzymes and microorganisms [120-122], The ultrasound generates the cavitation or bnbble implosion in the media. This implosion can cause inactivation of the enzyme and destrnction of microorganisms. The simultaneons pressnre treatment maximizes the intensity of the explosion, which increases the level of inactivation. The MTS technique avoids the adverse effects of elevated temperatures on quality and also resnlts in reduced energy requirements and therefore rednced costs. 

A HTST process was proposed for osmotic dehydration by Mastrocola et al. [118], Lerid et al. [78], Levi et al. [150], and Dijbrowska and Lenart [151]. The process is conducted at 65°C-90°C at a time of 1-20 min. The degree of dehydration is equivalent to that at 20°C lasting for 2 h. The HTST process also gives the effect of blanching, which inactivates enzymes and removes part of the air from the intercellular space. 

Liver Phosphorylase. Liver phosphorylase has been highly purified but not crystallized. It has been shown to contain firmly bound phosphate that does not exchange during activity. The enzyme phosphate is lost on incubation with another inactivating enzyme, and the resulting de-phosphophosphorylase is an inactive protein of about the same size as... 

It is important to have experimental criteria by which to judge whether an inhibitor requires catalytic conversion and whether direct inactivation of the enzyme occurs. The following criteria may be used to decide these points (1) The kinetics of inactivation should be first order in inhibitor concentration. (2) The pH vs. rate profile for inhibition may be similar to that for substrate turnover. (3) If C—bonds are cleared, a deuterium isotope effect should be manifest during the inhibition. (4) Trapping agents, such as mercaptans, should not decrease the rate of inactivation by inhibitor. The rate would decrease if the reactive molecule first diffused into solution and only later inactivated the enzyme by an affinity labeling or nonspecific mode of inactivation. (5) If a second aliquot of fresh enzyme is added to a solution containing inactivated enzyme and excess inhibitor, the rate of inactivation of the second... 

The inactivated enzyme and the native isomerase are electropho-retically distinct, yielding Rj values of 0.51 and 0.54, respectively, upon electrophoresis on polyacrylamide gels at pH 9. 

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