The uptake of vitamins by mouse fibroblast cells (strain LS) during growth in a chemically defined medium.

The uptake of biotin, choline, folic acid, hypoxanthine, inositol, nicotinamide, pantothenic acid, pyridoxine, riboflavin, thiamine and vitamin B,, by mouse LS cells in suspension culture was determined by microbiological assay methods. Based on the extent of uptake during cell growth, vitamin growth yields (cells produced/unit mass of vitamin utilized) were estimated for all of the vitamins, except folic acid, thiamine and B12. The growth yields were lower during the early phases of culture. No uptakes of folic acid or BH could be demonstrated. During the period of incubation about half of the thiamine was irretrievably lost through spontaneous decomposition.