URIC ACID LEVELS IN MEN FED ALGAE AND YEAST AS PROTEIN SOURCES

摘要

SUMMARYMicroorganisms grown on human or industrial waste products may be economical and nutritious food sources. Algae (Chlorella sorokiniana) harvested from continuous culture and extrakted with ethanol, and yeast (food‐gradeTorulopsis utilis) were compared with casein at 2 levels of nitrogen as the sole source of protein for men. Biological value of algal protein was superior to casein, and yeast protein was not quite as good as algae, in diets containing 25 g of protein. When 50 g of algae protein was consumed, true nitrogen digestibility was reduced from 89 to 82. Nitrogen balances were not significantly different in groups of men fed the higher protein level, indicating that 50 g of any of these proteins met or exceeded dietary requirements. Urinary uric acid excretion was doubled when the higher level of algae was ingested; with yeast, excretion was nearly 4 times as high as the amount voided with a purine‐free diet. During ingestion of these materials, renal clearance rates were not sufficient to prevent plasma uric acid concentrations from reaching abnormally high levels, comparable to those found in g