[Heterogeneity of molecular forms of phenol oxidase from grape leaves].

The substrate specificity and some kinetic properties of the monomeric (Mr = 26 000--35 000) and dimeric (Mr = 55 000--70 000) forms of phenol oxidase from vine leaves were studied. These forms possess different hydroxylating and o-diphenol oxidase activities. A kinetic analysis demonstrated that the monomeric form of the enzyme possesses a higher affinity for monophenols and can more effectively accomplish the hydroxylation reaction as compared to the dimeric one.

[Interrelationship between glucoside-bound and free alcohols during ether oil formation in rose petals].

Some data on the dynamics of free and glucoside-bound monoterpenic and aromatic (beta-phenylethyl) ethers content and the changes in the beta-glucosidase activity in rose petals at different stages of the flower development and on the kinetics of enzymatic hydrolysis of these glucosides are presented. The phase specificity of beta-glucosidase coinciding with the maximal accumulation of glucoside-bound and free alcohols is revealed. The data obtained suggest that the formation of glucosides may precede the accumulation of corresponding free alcohols of terpenic and aromatic origin.

[Biosynthesis of beta-phenylethanol in rose petals].

Biosynthesis of beta-phenylethanol is studied in a cell-free rose petals extract. This compound found to be synthesized via two intermediates: either trans-cinnamic acid, or phenylacetaldehyde. Subsequently beta-phenylethanol is glucosodized into its transport form, beta-phenylethanol- beta-D-glucoside.

[Heterogeneity of molecular forms of phenol oxidase from apple fruits].

Qualitative differences of a dimer (m.w. 60.

[Metabolism of phenolic compounds in plants].

A review is given on mechanisms of hydroxylation (the introduction of the first hydroxyl group into C-2 and C-4 positions of cinnamic and benzoic acids; the introduction of the second and the third hydroxyl groups into molecules of phenolcarboxylic acids and flavonoids), dehydrogenation (with participation of phenol oxydase and peroxydase) and deep oxidative degradation of phenolic compounds in plant tissues and cell cultures. Data on compartmentation of respective enzyme systems are also considered.