38 FATS, OILS, AND WAXES 



parallel increase in the amounts of carbohydrates, proteins, 

 and fats. 



During the germination of oily seeds a reversal of this 

 process takes place. The work of Schmidt, Green,* Le Clerc 

 du Sablon, and others, has shown that the first process is that 

 of hydrolysis which splits the fat into a fatty acid and glycerol, 

 lipase being the active agent. 



Thus in the sunflower Miller f found that less than i per 

 cent of free fatty acid was present in the oil of the cotyledons 

 of the resting seed ; as germination proceeded there was a 

 gradual increase, thus the ether extract of the cotyledons of 

 a seedling in which the plumule was just showing contained 

 30 per cent of fatty acid. 



The presence of the acid may be demonstrated in such 

 germinating seeds, but the same statement does not hold for 

 glycerol, probably because it is translocated with great 

 rapidity, and is quickly transformed. There can, however, 

 be no doubt that this substance is formed because if, for 

 example, castor oil be subjected in vitro to the action of lipase 

 obtained from Ricinus seeds, the presence of glycerol may be 

 detected with ease. 



With regard to other changes which the original fat under- 

 goes during germination, Schmidt found that the iodine number 

 of the unsaturated acids and oils decreased during germina- 

 tion, which indicates that saturation of the acid radicles 

 takes place. This is controverted by von Furth,J who found 

 no change in the iodine value. The observations of Schmidt, 

 however, have been corroborated by Miller, who found that in 

 Helianthus annuus the iodine value decreased from 136-2 

 for the seed to 67*4 for a seedling with the plumule just 

 elongating. 



Further corroboration is given by Ivanow § who, for his 

 study on the transformation of fats during germination, selected 

 flax, hemp, rape, and poppy seeds, since each is characterized 



* Green : " Proc. Roy. Soc, Lond.," 1890, 48, 370. 

 t Miller : " Ann. Bot.," 1910, 24, 693. 



X Von Furth : " Hofm. Beitr. Chem. Phys. Path.," 1904, 4, 430 ; 1912, 

 26, 889. 



§ Ivanow : " Jahrb. wiss. Bot.," 1912, 50, 375. 



