PYRIDOXINE 



sulphanilic acid. The results obtained by different workers have not 

 always been consistent, especially for meats. 



Cereals 



Whole wheat contains 3-2 to 6-i ; ^' ^' ^° wheat germ, 16 ; ■*» ^^ 

 wheat bran, 14 ; ^^ white flour, 1-2,'' 2-2 ; ^ whole wheat bread, 4-2 ; ^ 

 white bread, i-o ; ' barley, 5 to 6 ; ^^ and yellow corn, 5 /xg. per g.* 

 Dried grass contains 8 fig. per g.^ There was little variation (1-2 to 

 3-1 /xg. per g.^^) in the vitamin Bg contents of flours of different per- 

 centage extractions, but the germ and the weatings contained three 

 times the amount present in wholemeal. ^^ Rice polishings contained 

 20 /xg. of vitamin Bg per g.^^ In general, flours contain approximately 

 half the amounts present in whole grain. ^^ 



Fruits and Vegetables 



Lemon juice and orange juice contain 0-35 and 0-52 to o-6o /ug. of 

 vitamin Bg per ml. respectively."^ Cabbage and beetroot contain 3 

 and I '3 /xg. per g. respectively.^^ 



Meat and Fish 



The following values have been reported for beef : muscle, o-8,^ 

 4-0,^3 2-3 ; "^ liver, 0-4,^ 7*3/^ 7*i ; ^ and for pork : muscle, 1-23,^ 

 6-1,^^ 6-8 ; ^ liver, 17, ^ 3*3/^ 5'9 "^ h-S- P^^" S- Sheep's liver and muscle 

 contain 14 and 5 /xg. per g. respectively. ^^ Henderson et al.^ record 

 the following values, expressed in /xg. per g. of dry matter for the vitamin 

 Bg content of beef, mutton and pork " offal " : kidney and muscle, 

 20 to 30 ; heart and liver, 10 to 15 ; spleen, pancreas, brain and lung, 

 8. Fish muscle contains 20 /xg. per g. of dry matter. Fried meat 

 exhibited the least loss of vitamin Bg ; roasting and stewing resulted 

 in the loss of 20 to 50 % of the original vitamin content. 



Miscellaneous 



Fresh milk contains i-7,-^^ 1*3 ; * pasteurised milk, 0-5 to o-6 ; ^ 

 reconstituted evaporated whole milk, 0-62 /xg."^ per ml. and dried milk, 

 8-2 /xg. per g.^^ Yeast is the richest available source of vitamin Bg, 

 containing up to 50 /xg. per g. ; ^^ brewers' yeast is several times 

 richer than bakers' yeast. "^ Only about half the vitamin Bg activity 

 of yeast was present in an extract made with 2N-sulphuric acid, but 

 the activity of the extract increased considerably on autoclaving with 

 dilute acid or on digestion with clarase.^* The optimal growth stimula- 

 tion of S. carlsbergensis was obtained when extraction was effected 

 within the^H range 1-5 to 2-0. Similarly, the full vitamin Bg activity 



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