GENERAL EVALUATION 329 



Fig. 16-1. Influence of crude extract from Baptisia leucophaea leaves upon Rf value of a 

 pure sample of hydroxylupinine. The samples are co-chromatographed so as not to com- 

 pletely overlap. Thus, the last block on the right has 8 appHcations of hydroxylupinine 

 and no Baptisia extract; the next block has 7 applications of hydroxylupinine and one 

 application of Baptisia extract. A single application of the Baptisia extract is sufficient to 

 completely alter the Rf of the pure alkaloid. The lower band is a second alkaloid present 

 in the Baptisia extract. (Brehm, 1962). 



upon the method of preserving, extracting, and chromatographing the 

 sample. It is likely that such artifacts are more important than is 

 generally recognized. Extensive changes following the harvesting of 

 plant material have been noted variously (Yoshida, 1961) but do not 

 necessarily occur (Dzhemukhadze and Nestyuk, 1961). Forsyth (1952) 

 found that 80 per cent of the total polyphenols in cacao beans were 

 removed within fifteen minutes when the beans were ground and 

 aerated in a buffered solution. Although conditions were probably 

 nearly optimal for the activity of oxidative enzymes, it is nevertheless 

 important to recognize that many chemical changes may occur follow- 

 ing harvesting, particularly influenced by the conditions at the time 

 of death of the tissues. Volatile constituents are especially susceptible 



