33 



apples which gives the reactions of laccase but does not seem 

 to be identical with it. 



Cazeneuve 31 found that laccase produced only a very slight 

 action in wines. He therefore attributed the disease to a partic- 

 ular enzyme and named it "Oenoxydase." He obtained it in the 

 form of a gum by precipitating it from the wine by the addition 

 of a large amount of alcohol. It colors guaiac blue, is active at 

 oC. and is not entirely destroyed at 65 C. He finds that the col- 

 oring matter of wines is a phenol-like body which is oxidized by 

 oenoxydase. 



Laborde 32 attributes the secretion of Oenoxydase to a mould, 

 Botrytis cinerea (sweet rot), which is present at the root of the 

 vine. 



Eduard SchaY 3 has especially examined the enzyme in Phyto- 

 lacca decandra. He used an extract prepared by macerating the 

 fresh parts of the plant in glycerin containing not more than 5 or 

 10% of water, for a few days, then filtering. He states that an 

 extract so prepared scarcely loses any of its activity for a year 

 and a half. He found the extract from the leaves to be the most 

 active, that from the root less active, and that from the flowers 

 the least active. 



Schar 34 states that the blue color produced by enzymes upon 

 tincture of guaiac depends upon the formation of a peculiar oxy- 

 gen combination with the resinous constituent of guaiac, the 

 guaiaconic acid. To the blue compound he gives the name ozon- 

 ized-guaiaconic acid. He also states that guaiaconic acid is very 

 sensitive to the action of acids, alkalies, light, air and water and, 

 that when the tincture is to be used as a reagent, it should be 

 prepared fresh, of the strength of 2 to 3 per cent, of resin free 

 from wood. 



The most valuable contributions regarding the action of sol- 

 uble ferments have been given in a series of articles by G. Bert- 

 rand 33 . He has given the name "Laccase" to the enzyme first 

 found in Japanese lac by Yoshida but since found in many plants. 



81 Compt. rend. 124, 1897, p. 406 and 781. 



82 Compt. rend. 126, 1898, p. 536. 



33 Vierteljahrsschrift d. Naturf. Ges. Zurich, XU (1896) 233. 



84 66 Versammlung deutscher Naturforscher und Aertze & Wien, 1904. 



85 Bull. Soc. 3d. Series to 51, p. 159, 1891. 

 Compt. rend. 119, p. 1012, 1894. 



