372 
INDIAN MEDICINAL PLANTS. 
ceolate, long, acuminate, entire, thinly coriaceous, usually quite 
glabrous, lateral nerves 8-15 pair, alternating with shorter in- 
termediate ones ; base rounded acute or oblique, petiolules 
slender, |-§in. long. Panicles axillary, with slender and 
drooping ramifications, much shorter than the leaves. Flowers 
pedicelled, scarcely j^in. diam., greenish yellow. Sepals 
ovate-obtuse. Petals much larger, oblong or obtuse. Disk 
5-lobed. Drupes £in. diam., compressed, glabrous, rugose, 
yellow or light brown; epicarp thin, bursting irregularly. 
Mesocarp fibrous. Kernel compressed, hard, surrounded by 
a vegetable wax (Kanjilal), “ mixed with the fibre,” adds 
Brandis. 
Use : — The juice of the leaves is said to blister the skin 
(Stewart). The fruit is considered officinal and is used in Kash- 
mir in the treatment of phthisis. 
Chemistry . — The sap is a thick, nearly white, alkaline cream, superficially 
oxidisable by air to an intensely black, impervious susbtance, insoluble in 
the usual solvents. 
Complete oxidation only takes place in the presence of a diastatic 
ferment, laccase, which can be separated from the other essential constituent 
of the sap by means of alcohol, in which it is insoluble. When precipitated 
by alcohol from aqueous solution, the crude laccase dries to white, opaque 
fragments, like gum, and is probably a mixture of the ferment with carbo- 
hydrates, as it can be oxidised to mucic acid, and hydrolysed to galactose 
and arabinose. 
From the portion of the sap soluble in alcohol, a substance, laccol, 
probably a polyphenol, can be precipitated by lead acetate. It is a thick 
oil, insoluble in water, but soluble in alcohol, &c., and is intensely irritating 
to the skin, as is the crude sap. Laccol is readily oxidisable in the air to a 
reddish, viscous, or resinous substance; in alkaline solution, it behaves 
like pyrogallol, blackening and absorbing oxygen with such rapidity as 
to become hot ; it reduces ferric chloride in alcoholic solution, forming 
a black, metallic derivative. 
When laccol is precipitated from alcoholic solution by an aqueous 
solution of laccase, the white emulsion rapidly blackens from absorption of 
oxygen ; but this does not take place if the laccase solution has been boiled, 
or if water alone^is the precipitant. The action of laccase on gallic acid 
&c„ is similar, the rate of absorption of oxygen being enormously increased. 
As the ferment has no action on starch, sugar, amygdalin, &c., it seems to be 
the first member of a new class of “ oxidising diastases." 
Since laccase is present in many plants, it seems not improbable that 
this diastase plays an important part in che respiration of plants. 
J.Ch.S. 1895 A I p. 380. 
