Cytokinins are one of the major groups of plant hormones . They stimulate anabolic processes , growth and cell division . The first was discovered cytokinin kinetin , or N-6 furfuryloadenina . Kinetin is an important component of the metabolic pathway that allows the cell to get rid of excess free radicals. This is in response to oxidative stress . The plant cells in the cytosolic fraction , and microsomal membranes are thylakoid cytokinin binding proteins - CBP ( Cytokinin called Binding Protein ) . Binding of them referred to cytokinin induces a physiological response . Kinetin is considered to be a potent inhibitor of oxidation processes , and glycosylation of proteins and nucleic acids in vitro. It is a potent antioxidant , both in vitro and in vivo , premature aging of human cells in cell culture in vitro. Kinetin influences the growth and shape of the cells , their growth , cytoskeletal structure , the synthesis of macro- molecules and compactness of lipofuscin . It acts preferably on the skin, improving the barrier function of the horny layer reduces water loss through the epidermis - TEWL ( transepidermal called Water Loss ), and improves skin tone . Both kinetin riboside and its exhibit cytotoxicity against melanoma cells . Another cytokinin is N- 6 - benzyladenine . It affects mainly cell division . It also has the ability to inhibit certain human protein kinases , including the CDKs . This is especially important in cancer cells. Benzyladenine derivatives stimulate apoptosis in cancer cells in various tumor types. N- 9 - benzyladenine inhibits the activity of phosphodiesterases (PDE ) . Furthermore, in cultures of fibroblasts has been demonstrated that N- 6 - benzyladenine induce cell elongation , weakness in their movements and increase adhesion to the substrate.