Kostychev, Sergei

Born Apr. 26 (May 8), 1877, in St. Petersburg; died Aug. 21,1931, in Alushta. Soviet biochemist, plant physiologist, and microbiologist. Academician of the Academy of Sciences of the USSR (1923). Son of P. A. Kostychev.

Kostychev graduated from St. Petersburg University in 1900 and was a professor there from 1914 and head of the subdepartment of plant physiology from 1916. In 1923 he became director of the Laboratory of Plant Biochemistry and Physiology of the Academy of Sciences of the USSR and of the State Institute of Experimental Agronomy (from 1930, the Institute of Agricultural Microbiology of the V. I. Lenin All-Union Academy of Agricultural Sciences) in Leningrad. Kostychev proved that alcohol fermentation is not the first phase of respiration (as was supposed before him), but that both these processes are related in having common intermediate products of the conversion of carbohydrates. He established that yeasts are capable of carrying out the Cannizzaro reaction with the accumulation of acids and alcohols and that the fungus Aspergillus niger can form citric acid. (Both these investigations were carried out in the process engineering of the first industrial plants of the microbiological industry of the USSR.) Kostychev established the ways by which plants reduce nitrates to ammonia. He showed that ammonia is formed when atmospheric nitrogen is fixed by Azotobacter. He elucidated the nature of changes that take place in photosynthesis in the course of 24 hours.