PRODUCTION OF STABLE ISOTOPICALLY-LABELLED L-LACTATE

DEUTERATED OR 13-CARBON-LABELED L-LACTATE IS WIDELY USED IN MEDICAL DIAGNOSIS AND CLINICAL RESEARCH. THE STABLE, ISOTOPICALLY LABELED LACTATE IS NONTOXIC, AND NO ETHICAL OR DISPOSAL PROBLEMS DETER ITS USE IN HUMAN SUBJECTS. BY VIRTUE OF THEIR ABILITY TO GROW IN D2O INSTEAD OF H2O AND TOUSE (13)CO2 AS THEIR SOLE SOURCE OF CELLULAR CARBON, ALGAE CAN INCORPORATE DEUTERIUM OR (13)C INTO THEIR BIOMASS. IN PHASE I, MARTEK CORPORATION WILL PRODUCE GLUCOSE AND A HIGH-PROTEIN EXTRACT FROM THE ALGA, CHLORELLA VULGARIS. THESE COMPOUNDS WILL BE USED AS NUTRIENT SOURCES FOR THE BACTERIAL BIOSYNTHESIS OF L-LACTIC ACID. TWO L-LACTATE-PRODUCING BACTERIA WILL BE USED AS THE TEST ORGANISMS, NAMELY LACTOBACILLUS CASEI AND RHODOBACTER CAPSULATUS.