Mannane as a Reserve Material 
in the Seeds of Diospyros Kaki, L, 
BY 
<L Ishii, Nogakashi. 
The fruit of Diospyros Kaki, L. (date-plum) is consumed 
in large quantities by the people of this country on account of its 
richness in saccharine matters. There are many varieties of 
the fruit, ranging in size from a small hen’s egg to a large 
apple. In color 1 ) of the epidermis they vary from light orange 
yellow to deep orange red. My preliminary experiments proved 
it probable that a wine of good quality might be prepared 
from the fruit. It may be also mentioned here that this fruit 
contains, when unripe, a considerable amount of a kind of tan¬ 
nin which disappears entirely during the ripening of the fruit. 
My investigations of the flesh of the fruit have shown that 
there is a great amount of dextrose and laevulose, but neither 
mannose nor galactose present. It is, therefore, surprising that 
the seeds of the fruit contain no trace of starch, but a soft 
white mass as a reserve material, which could be easily con¬ 
verted into a sugar by boiling with sulphuric acid of 5% 
for one hour. After removal of the sulphuric acid with barium 
carbonate, the filtrate was evaporated, when a red-colored sub¬ 
stance was gradually deposited ; this was filtered off and the 
solution after being decolorized with animal charcoal was 
further concentrated. I obtained a sweet syrup which yielded, 
with acetate of phenylhydrazin in the cold, a considerable 
amount of crystalline precipitate, which upon recrystallization 
formed white tabular rhombic crystals, melting at I95°C (man* 
nose-phenylhydrazon). By mixing a certain quantity of acetate 
of phenylhydrazin with the aqueous solution of the crystals 
and heating the mixture, there were formed gradually yellow 
1) This coloring matter is turned blue by treatment with concentrated sul¬ 
phuric acid. 
