650 



VI. CAROTENOIDS AND RELATED COMPOUNDS 



300 400 500 



WAVE LENGTH IN M;jL 



Fig. 28. Molecular extinction curves of pro-7-carotene in hexane: ( — ) fresh 

 solution of pro-7-carotene; (- -) mixture of stereoisomers after iodine catalysis at 

 room temperature in light. ^^^ 



o 10 



H 5 



300 



400 



WAVE LENGTH IN MJX 



500 



Fig. 29. Molecular extinction curves of all-c/s-lycopcne in hexane: ( — ) fresli 

 solution of all-c<s-lycopene; (--) mixture of stereoisomers after iodine catalysis 

 at room temperature in light.^*^ 



