546 NIACIN 



20%, although with some foods and cooking methods losses as high as 

 50% have been recorded.^'- ^*"''^ The references cited are intended to be 

 only representative and do not even begin to cover completely the volumi- 

 nous literature on this subject. 



E. INFLUENCE OF SOIL, ENVIRONMENT, AND HEREDITY 



Soil and its nutrients can play some role in the nicotinic acid content 

 of plants. McCoy and coworkers'*^ found that a reduction in the major 

 ions in their nutrient solution reduced the nicotinic acid content of oats. 

 Hunt and associates^" reported that liming the soil, or adding nitrates, 

 increased the nicotinic acid content of wheat. Liming decreased the nicotinic 

 acid content of oats in a dry year. Gough and Lantz^^ studied eight varieties 

 of beans grown in three widely different localities and found that environ- 

 ment influenced nicotinic acid content. Gustafson^- found more nicotinic 

 acid in tomatoes, beans, and soybeans grown at 28 to 30° than at 10 to 

 15°; the reverse was true with broccoli, cabbage, spinach, clover, peas, and 

 wheat. 



However, the magnitude of the effects produced by soil and environment 

 seems to be much less than the influence of heredity, within the limits of 

 reasonable production yields. McElroy and Simonson^^ found no correla- 

 tion between soil type and nicotinic acid content for oats, wheat, and barley 

 grown in three different parts of Alberta. Richey and Dawson^* found that 

 extreme differences in production practices, i e., fertilizers, green manures, 

 etc., had no significant influence on the nicotinic acid content of corn, al- 

 though different inbred strains of corn varied from 13.9 to 53.3 7 per gram 

 of nicotinic acid. Hunt et al.^^ examined samples of nine corn hybrids grown 

 at five different locations for 2 years. There were differences in nicotinic 

 acid content for both years and at all locations. However, the variations 

 were small compared to the variations in nicotinic acid content characteris- 



" R. M. Griswold, L. M. Jans, and E. G. Halliday, J. Am. Dietet. Assoc. 25, 866 



(1949). 

 " E. Hartzler, W. Ross, and E. L. Willett, Food Research 14, 15 (1949). 

 ^« A. Lopez-Matas and C. R. Fellers, Food Research 13, 387 (1948). 

 « B. S. Schweigert, J. M. Mclntyre, and C. A. Elvehjem, J. Nutrition 27, 419 (1944). 

 ^8 K. Causey, E. G. Andreassen, M. E. Hausrath, C. Along, P. E. Ramstad, and F. 



Fenton, Food Research 15, 237, 249, 256 (1950). 



49 T. A. McCoy, S. M. Free, R. G. Langston, and J. Q. Snyder, Soil Sci. 68, 375 

 (1949). 



50 C. H. Hunt, L. D. Rodriquez, and R. M. Bethke, Cereal Chem. 27, 79 (1950). 

 " H. W. Gough and E. M. Lantz, Food Research 15, 308 (1950). 



" F. G. Gustafson, Plant Physiol. 25, 150 (1950). 



" L. W. McElroy and H. Simonson, Can. J. Research 26F, 201 (1948). 



" F. D. Richey and R. F. Dawson, Plant Physiol. 23, 238 (1948). 



55 C. H. Hunt, L. Ditzler, and R. M. Bethke, Cereal Chem. 24, 355 (1947). 



