CAROTENOIDS 



LICHENS 



KohP reported carotenoids in the lichen Baeomyces roseus and, by 

 implication they occur in a number of short lichens because these were 

 vitamin A-active when fed to rats ^ (see p. 27 for a discussion of vita- 

 min A-active carotenoids). The lichen Roccela montagneiy which grows 

 on sandal-wood trees, contains 28-40 mg. of carotene per 100 g. dry wt. 

 and a little cryptoxanthin. ^^ Apart from these pieces of information 

 nothing is known of lichen carotenoids. 



FUNGI 



In considering fungal carotenoids it will soon become clear that this 

 group differs from phanerogam carotenoids in four main respects : 



(1) Carotenoids are often completely absent from fungi. 



(2) p-Carotene is by no means such a common fungal carotenoid 

 as it is in Phanerogams. 



(3) Characteristic carotenoids are often present in fungi which are 

 acidic in character, being similar to astaxanthin. No such pig- 

 ments occur in Phanerogams. 



(4) The characteristic xanthophyll of higher plants — lutein — has 

 never been detected in fungi and the other phanerogam xantho- 

 phylls only rarely. 



Whilst bearing these striking differences in mind it should be noted 

 that the Phalloidaceae resemble the higher plants in one respect, that 

 is in having their carotenoids grouped round the nucleus of the chromo- 

 plasts. ' 



Before discussing the carotenoids in the various classes of fungi, it 

 will be convenient to point out here that carotenoids have been looked 

 for in a number of fungi and found absent. The species concerned are 

 listed in Table 13. It is appreciated that in all probability many other 

 fungi do not produce carotenoids but this list is confined to those 

 species which have been specifically investigated from this point of 

 view. 



The pioneer work of Kohl ^ and Zopf ^ ® also indicated that carotenoids 

 were probably present in a number of species which have never been 

 further examined using modern techniques. These species are listed 

 in Table 14. 



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