100 
ON THE OCCURRENCE OF MUCIN IN PLANTS. 
C 52,82 
H 7.53 
N 14,20 
0 +S (calculated) 25,05 
Ashes 0,41. 
The determination of N was made after the method of 
Kjeldahl. The substance contains sulphur. By boiling it with 
caustic potash of 5%, the liquid became yellowish, and when 
hydrochloric acid was added in excess, sulphuretted hydrogen 
gas was evolved, and the paper moistened with lead acetate 
turned black owing to the formation of lead sulphide. 
The composition of this slime is approximately the same 
as that of the bile (see the following table). Identity is of 
course doubtful, as there are many isomeric, especially stereo- 
isomeric mucins, 
possible. 
c 
H 
N 
S 0 Ashes 
Mucin of tendon 1 ) 
48.30 
6.44 
ii-75 
0.81--- 
Mucin of submaxillary glands 2 ) 
48.84 
6.80 
12.22 
0.84-- 
Mucin of bile 3 ) 
53-09 
7.60 
13.80 
I. xo 24.41- 
Mucinous substance 
of yam roots 
52.82 
7-53 
14.20 
r 
25.04 0.41 
Hammarsten declares: ‘‘Die Fähigkeit, beim Sieden mit 
verdünnten Säuren eine reducierende Substanz zu geben, die 
physicalische zähe Beschaffenheit und das Verhalten zu Es¬ 
sigsäure sind die drei wichtigsten Eigenschaften, welche die 
Mucinstoffe in qualitativer Hinsicht von dem Eiweissstoffen 
unterscheiden.” Our slime shows all the essential charac¬ 
teristics of the animal mucin, and differs only in some sub¬ 
ordinate points; it is with more difficulty soluble in dilute 
alkalies and yields a turbidity with potassium ferrocyanide. 
Our substance is doubtless a kind of mucin, and as this is 
the first time that such a compound has been found in the 
vegetable kingdom, it is certainly of physiological interest. 
The quantily determined as accurately as possible, amounts 
to 8 % of the tuber dried at ioo°C. 
1) Loebisch, Ztschr. physiol. Chem. Bd. X, S. 61. 
2) Hammarsten , Ztschr. physiol. Chem. Bd. XII, 
3) Landwher , Ztschr. physiol. Chem. Bd. V, S. 371. 
