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Pig liver acetone powder

Acetone Powder Containing Esterase Activity. The main advantage in using crude homogenates or acetone powders of organs such as liver is to have a cheap source of different enzymes. If one of these is desired for a specific substrate, the crude enzymatic mixture can be used with some advantage, compared to the purified enzymes. Pig liver acetone powder (PLAP), together with other extracts, is commercially available or can be prepared from fresh pig liver. PLAP has been used for the enantioselective hydrolysis of the racemic acetate of rrans-2-phenylcyclohexanol... [Pg.331]

The use of ester hydrolase preparations such as pig liver esterase (PLE) or pig liver acetone powder (PLAPy complements reduction approaches for the synthesis of enantio-enriched alcohols. [Pg.129]

This chiral alcohol (—)-l can be obtained from racemic I by conversion to the chloroacetate (reaction with CICH2COOH), which is saponified by enzyme Pl.AP (pig liver acetone powder) at 40% conversion to give (—)-l and the (+)-estcr, which can then be saponified to provide (+)-l. [Pg.55]

The first simple method using isotopic labelling has been developed to confirm the actual and observed selectivities in the enzymatic hydrolysis of unsymmetrical diacetates and to measure the enzyme selectivity efficiency. The simple method consists of enzymatic hydrolysis of the unsymmetrical diacetate followed by labelling of the hydroxyacetate formed with CD3CO2D-DCC and enzymatic rehydrolysis of the labelled compound under identical reaction conditions. The amount of label lost, as determined by H NMR spectroscopy, directly indicates the extent of regioselective action of the enzyme. For example, enzymic hydrolysis using pig liver acetone powder (FLAP) of the racemic glycerol diacetate (208) yielded a mixture (1 9) of the 1-hydroxy ester (209) and the 2-hydroxy ester (210). Isolation of the 2-hydroxy... [Pg.101]

H0-CH(C2C00CH3)-CH2C00CH3 Horse liver acetone powder, pig liver acetone powder, Streptomyces griceus [15]... [Pg.387]

Asymmetric reduction of the ketone on a 1.0-g (4.0-mmol) scale to provide (R)-(-)-2,2-diphenylcyclopentanol (96% ee) has been reported employing (+)-( -chlorodiisopinocampheylborane however, the reaction is extremely slow and inefficient [70% yield, 5 days, 2.6 equiv of (+)-p-chlorodiisopinocampheylborane].5 Other efforts to obtain enantiomerically pure 1 by means of enzymatic hydrolysis of the corresponding racemic acetates using horse liver acetone powder (HLAP) and pig... [Pg.45]

Pig pancreatic lipase added to a mixture of ethyl butyrate, ethyl isobutyrate, and ethyl pivalate in phosphate buffer (pH 8), and quenched with 10 M NaOH when reaction complete (pH-stat method) - butyric acid. Y 65% (> 95% purity). The enzyme only hydrolyzed straight-chain esters. F.e., preferential cleavage of functionalized esters, and comparison with horse liver acetonic powder, s. B. De Jeso et al., Synth. Commun. 18, 1699-705 (1988) preferential hydrolysis of dicarboxylic acid esters s. ibid. 1691-7. [Pg.299]

Until recently the synthesis of flavin adenine dinucleotide had not been studied with purified enzymes from animal tissues. However, the ability of animal tissues to synthesize this coenzyme has been known for a number of years. Klein and Kohn 138) observed formation of flavin adenine dinucleotide in red blood cells in vivo and in vitro, and Trufanov 139) obtained synthesis of flavin adenine dinucleotide in rat tissue slices. Makino et al. 130) obtained formation of flavin adenine dinucleotide from vitamin Ba and ATP in the presence of pig kidney acetone powders, and Yagi 129) reported the synthesis of the coenzyme by the action of acetone powders of rabbit liver or kidney from riboflavin 5 -phosphate, but not riboflavin, and ATP. [Pg.704]

Wash pig liver with water and remove as much Wood as possible. Homogenize chopped pig liver in a blendor with the same volume of Soln. A and cool the homogenate to 0 °C. Pour slowly the homogenate to 10 vol. of acetone cooled to -15 °C. Allow to setde at -15 °C and filter the sediment on a Buchner funnel. Wash the tissue twice with three volumes of cold acetone, followed by a wash with cold diethylether. Spread the dehydrated tissue on filter paper, grind up, allow the solvent to evaporate and store it in a desiccator containing anhydrous calcium cWoride at 4 °C. The white liver powder remains stable for months. [Pg.148]

Coon and his co-workers (24-26), employing acetone powder extracts of rat and pigeon liver and enzyme fractions from pig heart, have recently obtained evidence that the formation of acetoacetate from the isopropyl group of isovalerate, and hence from that of... [Pg.44]

Phenylalanine hydroxylase is like p-hydroxyphenylpyruvate oxidase (see below) in its requirement for two enzyme components. It is particularly interesting that one of these components (Fraction II) can be replaced by acetone powder extracts of liver from rabbit, calf, dog, and pig, and by acetone powder extracts of kidney and heart from calf and hog, although these oi ans contain no phenylalanine hydroxylase activity. Fraction II appears to be wide distributed, and to have fimctions other than these connected with phenylalanine hydroxylation. Although two enzyme components are involved in the system, no evidence for an intermediate between phenylalanine and tyrosine has been found (557), nor has it been possible to separate the process into two steps. [Pg.182]


See other pages where Pig liver acetone powder is mentioned: [Pg.1960]    [Pg.1960]    [Pg.1960]    [Pg.352]    [Pg.1002]    [Pg.145]    [Pg.304]    [Pg.1960]    [Pg.1960]    [Pg.1960]    [Pg.352]    [Pg.1002]    [Pg.145]    [Pg.304]    [Pg.344]    [Pg.305]    [Pg.388]    [Pg.330]    [Pg.63]    [Pg.702]    [Pg.300]    [Pg.90]   
See also in sourсe #XX -- [ Pg.55 ]

See also in sourсe #XX -- [ Pg.55 ]




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Liver acetone powder

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