THE PIGMENTS OF MICRO-ORGANISMS 393 







CH3 



. Ill alkaline solution it can undergo a tAvo- 

 OH 



O 

 stage oxidation-reduction reaction and may be concerned 

 in the metabolism of the organism. It has some vitamin 

 K (antihsemorrhagic) activity and raises the prothrombin 

 content of the blood, on injection. 



The red yeasts, such as Torula rubra , produce caro- 

 tenoid pigments, including jS-carotene, tonilene, and a 

 polycarboxylic acid pigment. The blue fluorescent 

 pigment thiochrome, C12H14ON4S, 

 N=C— N==C— S 



I I I ^C.CHa.CHjOH 



CH3.C C— CH2— N— C 



II II I 

 N— CH CH3 



is derived from aneurin, or vitamin-Bi, which occurs in 



considerable amounts in yeasts. 



The pigment aspergillin, from the black spores of 



A . niger, is a melanin type of pigment soluble in alkali . 



Fumigatin, 3-hydroxy-4-methoxy-2 : 5-toluquinone, 







CH3/ ]jOH 



, maroon coloured crystals, m. p. 116° C, from 

 " 'ioCH ' 



o 

 A.fumigatus and spinulosin, 3 : 6-dih3Tlroxy-4-methoxy- 

 



' CHg 



II 11 



2 : 5-toluquinone, jiq\\ IIqch ? purple plates, m.p 



