Emulsin

Emulsin (0-glycoaidase) almond nuts P-glucosides glucose and a non-carbohydrate 4I-4-5... 

Emulsin, an enzyme readily obtained from almonds, has the property of hydrolysing 3-glycosides. 

Emulsin does not hydrolyse a-methylglucoside, whereas it readily hydrolyses -methylglucoside, salicin, amygdalin and arbutin. This is an excellent example of the specificity of enzymes ... 

Since an enzyme is a biological catalyst and therefore merely accelerates a reaction, it cannot alter the position of equilibrium in a reversible reaction. The hydrolysis of p-methylglucoside is reversible and emulsin should therefore be capable also of synthesising this compound frc n glucose and methanol. This synthesis can actually be carried out by the action of the enzyme on glucose dissolved in an excess of methanol, the excess of the alcohol throwing the equilibrium over to the left. Owing to experimental difficulties, this reaction is not here described. 

In aqueous solution, the hydrolysis of a glucoside by emulsin goes to completion on account of the large proportion of water present. 

Salicin is a colourless crystalline substance, soluble in water. It does not reduce Fehling s solution nor does it give a coloration with ferric chloride. On hydrolysis with emulsin, glucose and salicyl alcohol are produced the former reduces Fehling s solution and the latter gives a violet coloration with ferric chloride. 

By gentle warming, dissolve 5 g. of salicin in 100 ml. of water contained in a 250 ml. conical flask. Add about 20 ml. of the emulsin solution as prepared above or o 2-0 3 solid enzyme prepara-... 

Phlonzm is obtained from the root bark of apple pear cherry and plum trees It has the molecular formula C21H24O10 and yields a compound A and D glucose on hydrolysis in the pres ence of emulsin When phlorizin is treated with excess methyl iodide in the presence of potassium carbonate and then subjected to acid catalyzed hydrolysis a compound B is obtained Deduce the structure of phlorizin from this information... 

As early as 1908, Rosenthaler found in the ferment mixture of emulsin a u-oxynitrilase , which directed the addition of hydrocyanic acid (hydrogen cyanide) to benzaldehyde asymmetrically to give x-hydroxybenzeneacetonitrilc (mandelonitrile)9. This result was confirmed1 °, however, it was not until 1963 that Pfeil ct al. first isolated and characterized the enzyme (R)-oxyni-trilase [EC 4.1.2.101 from bitter almonds (Prunus amygdalus)1 12. The yellow-colored enzyme contains a flavin-adenine dinucleotide (FAD)11 and loses its activity by splitting off this prosthet-... 

His work on enzymes was continued during the Bonn period. Studies on acid phosphatases were carried out that made a major contribution to our knowledge of these enzymes. " The isolation of a crystalline /3-glucosidase from the emulsin of sweet almonds may be regarded as the crowning achievement of his work on glycosidases. ... 

Glucosidase and 0-galactosidase (sweet almond emulsin)[36] Glutamine synthetase (native octameric brain) 371 Glycogen phosphorylase At3 ]... 

Elimination, of hydrobromic acid from a dibromide, 22, 50 of hydrobromic acid from a dibromide with rearrangement, 24, 33 Emulsin, 22, 53 Enzymatic synthesis, 22, 53... 

This osone was first prepared from cellobiose phenylosazone by the benzaldehyde method196 on hydrolysis by emulsin it gave D-glucosone and D-glucose. 

Melibiosone was prepared by the action of benzaldehyde on melibiose phenylosazone17-191 and was identified by conversion into melibiose p-bro-mophenylosazone. On treatment with emulsin, it was hydrolyzed to D-glucosone and D-galactose.17,203... 

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