[The search for cytostatic substances in the tissues of plants of the genus Maytenus molina in in vitro culture. I. Callas culture and biological studies of its extracts].

Plant tissue cultures of Maytenus wallichiana Raju et Babu and Maytenus emarginata Ding Hou were initiated. Growth conditions of the callus and the optimum medium composition have been established. Increments of callus wet mass and dynamics of callus growth were determined. Morphological and microscopic observations were also performed. The most efficient growth of the callus, resulting in increments of its wet mass up to 6460%, was obtained on the modified Murashige and Skoog medium. Extracts of the callus were found to be inactive against microorganisms, but proved cytotoxic for lymphocytic leukaemia L 5178Y (ED50 18-48 micrograms/cm3) and the protozoon T. pyriformis (ID50 43-53 micrograms/cm3).