KINO 439 



ducts intermediate between the soluble kinotannic acid and the in- 

 soluble kino-red. This change from kinotannic acid to kino-red 

 commences immediately the juice is exposed to the air, as evinced by 

 a darkening in colour ; it is continued slowly in the dry drug which 

 becomes duller and less soluble, and proceeds rapidly in solutions of 

 the drug, which may gelatinise owing to the formation of insoluble 

 kino-red. It is caused by the presence of an oxydase enzyme, and 

 may be prevented by destroying the activity of the enzyme by boiling 

 the juice or the solution of the drug. Hence the boiling of the juice 

 before evaporation, as required by the British Pharmacopoeia, is a 

 rational procedure. 



In addition to kinotannic acid and kino-red the drug contains about 

 10 to 15 per cent, of moisture, and small quantities of pyrocatechin 

 (catechol), gallic acid, and mineral constituents (ash 1'5 per cent.). 



Uses. Kino is a powerful astringent ; it is given internally for 

 diarrho3a and dysentery and is also used externally. 



Varieties. Kinos have been obtained from numerous plants belong- 

 ing to various natural orders, including Legumincsce, Myrtacece, 

 Polygonacece, Myristicacece, and Saxifragacece. Of these kinos the 

 following may be briefly mentioned : 



1. Red gum (see below). 



2. Butea gum (see below). 



3. Eucalyptus or Botany Bay kino from various species of Eucalyptus 

 (Australia), the most suitable being E. calophylla ) R. Brown, the tannin 

 of which does not gelatinise. The drug occurs in irregular dark red 

 pieces. 



4. African kino from Pterocarpus trinaceus, Poiret, in West Africa. 

 It closely resembles the official drug. 



5. Jamaica Kino is an extract obtained by evaporating a decoction 

 of the leaves, wood and bark of Coccoloba uvifera^Lirme (N.O. Poly- 

 gonacece). 



RED GUM 



(Eucalyptus Kino, Gummi Eucalypti) 



Source, &C. Eucalyptus Kino, or as it is commonly termed ' red 

 gum,' is a variety of Australian kino obtained from Eucalyptus rostrata, 

 Schlechtendal (N.O. Myrtacece), and other species (E. marginata, Smith, 

 E. amygdalina, Labillardier, &c.). They are all Australian trees, E. 

 rostrala forming large forests on the banks of the Murray River in New 

 South Wales and yielding a valuable timber. This species is usually 

 preferred as the source of red gum for medicinal use, because the tree is 

 gregarious, cannot easily be mistaken for others, and yields freely 

 a drug of good quality. The gum, which is secreted in cavities in the 

 wood, or sometimes between the bark and the trunk of the tree, forming 



