Note on the Chemical Composition of some Mucilages. 



BY 



K. Yoshimura, Nojakushi. 



The mucilages or saccharo-colloids, hitherto analysed, 

 have been found to consist, in most cases, of saccharo polyan- 

 hydrides of either glucose, galactose, mannose, or arabinose. 

 Only in one case was the mucilage shown to consist of a mucin 

 {hhii, Vol. II. No. 2 of this Bulletin). 



Although such compounds are widely distributed in the 

 vegetable kingdom, they have been investigated but in a very 

 limited number of cases. As it is of physiological interest to 

 know the composition of mucilages in as many plants as possible, 

 I have examined those of the following species : 



1. Stcvculia platanifolia (young shoots). 10 



2. Colocasia antiquorum (tuberous roots).' 2 ' 



3. Opuntia (fleshy stem). 



4. Vitis pentaphylla (stems and leaves). 



5. Oenothera Jaquinii (stems and leaves). 



6. Kadzuva japonica (young leaves and stems). 



The concentrated slimy extracts were precipitated with 

 strong alcohol and the precipitates, after having been washed 

 with alcohol, were boiled with sulphuric acid of 2-4 % for 2-5 

 hours, the liquid neutralised with barium carbonate, and the 

 filtrate evaporated to a syrup. 



A portion of this syrup was evaporated with nitric acid to 

 observe whether mucic acid was formed. 



Another portion was mixed with a cold concentrated solu- 

 tion of acetate of phenylhydrazine to observe whether mannose- 

 phenylhydrazonc was formed. 



(1) The mucilage of Stcrcidia platanifolia, as well as that of Kadzura japonica, 

 finds technical application in this country, being used for sizing paper, etc. 



(2) The tuberous rootstock of Colocasia antiquorum serves as a valuable food in 

 this country, and is hence cultivated to a large extent. 



