During the first part of his career Ricard's research was dedicated to the study of enzymes involved in plant metabolism, including yeast hexokinase, a collaboration with
R. J. P. Williams on turnip peroxidases, and other work on peroxidases. A long-term interest in
allosteric and
cooperative behaviour led to a retrospective review two decades after the principal models of cooperativity were established. The study of yeast hexokinase as an example of
enzyme memory, later extended to multienzyme systems, following a discovery that five enzymes of the
Calvin cycle existed as a complex in
chloroplasts. In the light of his textbook he became a member of the panel that prepared the current
IUBMB recommendations on enzyme kinetics. In 1983 Ricard organized, with
Athel Cornish-Bowden, a NATO Advanced Research Workshop in Marseille on
Dynamics of Biochemical Systems in which several notable scientists participated:
Keith Dalziel,
Albert Goldbeter,
Mario Markus,
Peter Schuster. After his formal retirement Ricard became increasingly interested in applying his training in mathematics to general questions of complexity and the origin and definition of life. == Honours ==