CHAPTER VI 



THE CHEMISTEY OP LIGHT PEODUCTION, PAET II 



Since Radziszewski 's experiments on the oxidation of 

 oils in alcoholic solutions of alkali, most of the early- 

 workers on Bioluminescence tacitly assumed that the oxi- 

 dizable material was fat or a fat-like substance. Support 

 was given to this view by the occurrence in cells of 

 granules or globules from which the light was seen to come. 

 We now know that these bodies are not fat droplets and 

 that neither luciferin nor lucif erase are soluble in such fat 

 solvents as ether, chloroform, benzol or benzine. Phip- 

 son's description of the properties of noctilucin are too 

 crude and inaccurate to be considered. Dubois did not 

 study the chemical properties of luciferin and luciferase 

 from Pyrophorus, the first form with which he worked, 

 except to point out that PyropJiorits luciferase was de- 

 stroyed on heating and was precipitated by alcohol while 

 the Pyrophorus luciferin was not so affected. Luciferin 

 was found only in the luminous organ of Pyrophorus, not 

 in the blood; luciferase probably exists throughout 

 the animal.^ * 



Pholas lxjciperin. — In a series of papers since 1887 

 Dubois has studied the chemical properties of Pholas 

 luciferin and Pholas luciferase. He finds the luciferin 

 to be destroyed above 70° C, to dialyze slowly, to oxidize 

 with light production in the presence of Pholas luciferase, 

 KMn04, H2O2, haematine and H2O2, Ba02, Pb02, hypochlo- 

 rites, and the blood of various marinfe moUusks and crus- 



* Private communication from R. Dubois. 

 114 



