Mandelonitrile prunasin

Salicin is an (9-glycoside of a phenol, namely salicyl alcohol. Salicin is a natural antipyretic and analgesic found in willow bark, and is the template from which aspirin (acetylsalicylic acid, see Box 7.13) was developed. Prunasin from cherry laurel is an example of a cyanogenic glycoside, hydrolysis of which leads to release of toxic HCN (see Box 7.7). It is the (9-glucoside of the alcohol mandelonitrile, the trivial name for the cyanohydrin of benzaldehyde. It is the further hydrolysis of mandelonitrile that liberates HCN. 

Prunus armeniaca L. Xing Ren (Apricot) (kernel) Amygdalin, prunasin, fatty acids, mandelonitrile (enzyme amygdalase can hydrolyze amygdalin to produce cyanic acid).33 53 Stimulate respiratory center reflexively and produce a tranquilizing effect. 

Treatment of racemic mandelonitrile with UDP-glucosyl transferase from the fruits and leaves of black cherry, Prums serotina, produces only (/ )-prunasin (19). These preparations did not convert prunasin to the diglycoside amygdalin (20) (Dewick, 1984). 

Gross, M., G. H. Jacobs, and J. E. Poulton, A rapid and sensitive spectrophotometric assay for prunasin hydrolase activity employing purified mandelonitrile lyase, Anal. Biochem., 119, 25-30 (1982). 

Sambunigrin (D-mandelonitrile glucoside) from the leaves of the elder tree—Sambucus nigra (Caprifoliaceae)—is isomeric to prunasin. 

Four cyanogenic glycosides (amygdalin, linamarin, prunasin, mandelonitrile) were extracted from apricots and separated on a C g column (2 = 200 nm or pulsed amperometric detection, ] = 0.00 V for 240 ms, = 0.60 V for 60 ms, ) = —0.80 V for 60 ms). For the amperometric analysis, a 0.5 M NaOH solution was fed into the effluent postcolumn. An isocratic 12 min 82/12 water/acetonitrile run or an 8-min 100/0- 40/60 water/acetonitrile gradient was used [1259]. Baseline resolution was achieved using the gradient... 

Bark contains condensed tannins, prunasin (d-mandelonitrile glucoside) emulsin eudesmic acid (3,4,5-trimethoxybenzoic acid) /i-couma-ric acid scopoletin sugars andothers (karrer). Fruit skin contains capulin anthocyanins. Prunasin is a cyanogenic glucoside that is hydrolyzed by the enzyme prunase into hydrocyanic acid (HCN, prussic acid). 

Among animals, this type of defence is practised by millipedes, centipedes and insects only. The larvae of the Australian beetles of Paropsis and Chrysophtarta, feeding on Eucalyptus leaves produce mandelonitrile and prunasin. When freeze-dried insects were treated with P-glucosidase and nitrilase, HCN was released (Figure 10.7). The larvae... 

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