NICOTINIC ACID (NIACIN) 



Salt-water fish on the whole constitutes a richer source of nico- 

 tinic acid than fresh-water fish,^^ the highest value observed in eight 

 varieties of salt-water fish purchased in Calcutta market being 3-1, and 

 in thirteen varieties of fresh-water fish, 1*77 mg. per 100 g. Trout, 

 however, contains 3-5 and perch 17 mg. of nicotinic acid per 100 g.^° 



Fish from Lake Michigan contained : ^^ lake herring, 2-3 to 5-5 ; 

 common suckers, I-i to 1-3 ; carp, 1-5 ; burbot, i-6 ; carp roe, 1-3 ; 

 and herring roe, o-6 mg. of nicotinic acid per 100 g. Wide individual 

 and seasonal variations were observed. No significant loss occurred on 

 freezing and subsequent storage for two to three months or on baking ; 

 smoked fish retained 66 to 72 % of the nicotinic acid originally present. 



Meat is another rich source of nicotinic acid, richer even than 

 fish, and the following values are recorded for muscle tissue : ^° ox, 

 3-8 to 10-2 ; calf, 4-9 to i8-o ; horse, 47 ; pig, 3-3 to 13-0 ; rabbit, 

 6-5 to 13-0 ; chicken, leg, 6-i to 8-o ; breast, ii-o to i8-i ; grouse, 

 6-5 ; and lamb, 5-4 to io-2 mg. per 100 g. The amount of nicotinic 

 acid in chicken muscle appeared to vary inversely with the aneurine 

 content, dark muscle containing three times as much aneurine as pale 

 muscle, but only one-half to one-third of the nicotinic acid.^* 



In general, kidneys are richer than the corresponding muscle 

 tissue, 1^ ox containing 6-5 to 19-4 ; pig, 4-1 to 15-5 ; calf, 8-3 to lo-o ; 

 rabbit, 3-8 to 16-2 ; sheep, 7-5 to 9-6 mg. per 100 g., whilst liver is 

 richer still, that of ox containing 7-6 to 27-5 ; calf, 11-5 to 22-5 ; 

 horse, i6-o ; sheep, 12-5 to 20-0 ; lamb, 39-2 to 46-0 ; pig, 97 to 27-5 ; 

 rabbit, 7-85 to 22-0 ; and chicken, 11-4 to 17-8 mg. per 100 g. Ox 

 tongue contains 6-i to 12 -8 mg. per 100 g. 



Other " offal " is a poorer source of nicotinic acid than kidney and 

 liver, the following values being recorded : adrenal, ox, 5-0 to 6-o ; 

 adrenal, sheep, 13-5 ; brain, ox, 3-0 to 7-5 ; brain, rabbit, i-2 ; heart, 

 ox, 4'9 to 5*9 ; heart, pig, 5-3 to 8-o ; heart, rabbit, 3-4 ; heart, sheep, 

 6-0 ; lung, ox, 4-3 to 8-3 ; lung, rabbit, 0-9 ; ovary, pig, 3-8 ; pancreas, 

 ox, 27 to 5*0 ; pancreas, sheep, 4-0 ; spleen, ox, 4-4 to 8-3 ; spleen, 

 pig, 4-0 ; and testis, pig, 4-4 mg. per 100 g. 



In animal tissues, nicotinic acid exists mainly in the form of nicotin- 

 amide or,i^ more probably, pyridine nucleotide, ^^ whereas plant 

 tissues contain a smaller, often a very much smaller, proportion of 

 nicotinamide. 



The richest readily available source of nicotinic acid, as of other 

 members of the vitamin B complex, is yeast. Bakers' yeast contains 

 7-4 to 12-0 mg. per 100 g., compressed yeast 257 mg. per 100 g. of 

 dry matter and dry yeast 25 to 50 mg. per 100 g. Dried brewer's 

 yeast contains 34 to 93 and moist brewer's yeast 9-1 to io-2 mg. per 

 100 g. Torula utilis contains 20 to 38 mg. per 100 g.^'' ^^ The yeast 

 extract, " Marmite ", contains 65-5 mg. per 100 g.^^ 



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