Abstract: A process for the preparation of a plasminogen activator is described, which comprises bringing normal diploid cells derived from human bodies capable of producing the plasminogen activator into contact with a solution containing an enzymatically-decomposed animal meat peptone, the plasminogen activator having the following properties:(a) molecular weight: 63,000.+-.10,000;(b) isoelectric point: 7.0 to 8.5;(c) affinity to fibrin: present;(d) affinity to Concanavalin A: present;(e) optimum pH: 7 to 9.5; and(f) no reactivity with anti-urokinase specific antibody.The plasminogen activator can be obtained in a high yield.

Abstract: A feed comprising a culture product of strains of marine or halophilic yeasts in which the COD rising index of the strain is not more than 150 and the RNA excretion rate is not more than 20% in a medium containing waste molasses and an inorganic nitrogen compound, and a method for cultivating aquianimals with the feed. Typical example of the yeasts is Torulopsis candida var. marina NRRL Y-7345. The feed is particularly useful for breeding, for example, Brachionus, Copepoda, Brine Shrimp and Stage of Zoea, Mysis and Post Larva of shrimps.