OTHER LEVULOSANES,PARAMANNANE,ETC. 121 



a brief treatment with hot dilute hydrochloric acid. These 

 reserve celluloses contain mannanes and galactanes. 



Mannane serves in the same way as starch as a reserve food- 

 supply to a very large number of different plants. It may be 

 regarded as an anhydride of mannose, since it yields this 

 substance on hydrolysis ; it occurs either alone or united to 

 anhydrides of other sugars, such as glucose, galactose, pentose, 

 etc., in a great many different forms. 



A fairly pure specimen of mannane can be obtained from 

 yeast by a somewhat elaborate method devised by Hessenland.* 

 It is a white amorphous substance, which is somewhat soluble 

 in water and swells up in dissolving ; it is insoluble in alcohol 

 but readily soluble in alkali, and is strongly dextro-rotatory 

 a D = + 2837-287-6. 



Mannane occurs in salep mucilage, and has been extracted 

 by Ritthausen f and Effront \ and others from wheat and 

 barley. Mannanes are also found in Penicillium glaucum, 

 ergot, in the roots of several plants such as asparagus, chicory, 

 Helianthus and Taraxacum ; also in the wood and leaves of 

 many trees, such as lime, chestnut, apple, mulberry, certain 

 Oleaceae and conifers ; the so-called reserve celluloses and 

 hemi-celluloses contained in seeds of Palmaceae, Liliaceae, 

 elder, cedar and larch, and many other plants, are also very 

 rich in mannanes. 



PARAMANNANE. 



Paramannane is a variety of mannane which is characterized 

 by being much more resistant to hydrolysis ; this substance, 

 which is contained in coffee beans, is only slightly acted on by 

 hot dilute mineral acids, potassium chlorate and hydrochloric 

 acid, but dissolves in a concentrated hydrochloric acid solution 

 of zinc chloride. It is accordingly frequently classed as a 

 mannose-cellulose. 



CARUBIN OR SECALANE. 



Carubin is the name given to a substance occurring in 

 the seeds of Ceratonia siliqua, and in various cereals such as rye 



* Hessenland: "Z. d. Vereins d. Deut. Zuckerind.," 1892, 42, 671. 



t Ritthausen: "J. prakt. Chem.," 1867, 102, 321, and " Chem. Zeit.," 1897 



21, 7*7- 



JEffront: " Compt. rend.," 1897, 125, 38, 116. 

 %Ibid., 124, 200, and 125, 116 and 309. 



