GfiO 



ABSORPTION SrECTRA OF PIGMENTS IN VITRO 



CHAP. 21 



a - Carotene 

 /3 - Carotene 

 Lycopene 



380 400 420 440 460 480 500 520 220 

 WAVE LENGTH, m/i 



280 340 400 460 



WAVE LENGTH, m/x 



520 



Fig. 21.31. Absorption spectrum of j8- 

 carotene in hexane (after Zscheile, White, 

 Beadle and Roach 1942). 



Fig. 21.32. Absorption spectra of a- 

 carotene, /3-carotene, and lycopene in 

 80% ethanol + 20% diethyl ether (after 

 Miller 1937). 



2.5 



2.0 



o 



Q 



1.5- 



2.4 



-20 



380 400 420 440 460 480 500 520 

 WAVE LENGTH, m/i 



400 



450 

 WAVE LENGTH, m/i 



1.5 

 500 



Fig. 21.33. Specific absorption spectra Fig. 21.34. Specific absorption coef- 

 ofluteol (solid line ) and zeaxanthol (broken ficients of luteol in ethanol (after Strain 

 line) in ethanol (after Zscheile, White, 1938). I, dried luteol. II, luteol with 

 Beadle and Roach 1942): c is in grams 2.65% petroleum ether. Dots, luteol in 

 per liter; d is in centimeters. ethanol as reported by Smakula (1934). 



Ill, pure luteol. IV, same after heating 

 3 hrs. at 77°. Values of log a for I and 

 II at left, for III and IV at right. 



