The nutritive properties of two yeasts used to produce massive dietetic liver necrosis in rats

Publisher Website
Google Scholar
Abstract
A comparison was made between the dietetic properties of British baker''s yeast and American brewer''s yeast, both of which were used as the sole source of protein in the production of dietetic liver necrosis in rats. Diets containing 7-8% of yeast protein were used. When fed to tocopherol-depleted weanling rats the baker''s yeast was more necrogenic than the brewer''s yeast diet. Growth expts. on normal weanlings also showed the inferior biological value of baker''s yeast. Rats fed the yeast diets for 33 days had liver glutathione contents which were 50% lower than those of normal rats. There was no difference between the composition of livers of rats fed either type of yeast. Different dietetic deficiencies exhibited by the 2 yeasts are discussed in relation to their contents of S, N, and amino acids. Brewer''s yeast contains 38% more cystine and glutathione than baker''s yeast. Comparison with Rose''s (1937) figures for minimum essential amino acid requirements for normal growth showed that both yeast diets were also deficient in other essential amino acids.