Use, in a cosmetic or pharmaceutical composition (A), of at least one lyophilizate (B) of dedifferentiated plant cells, where (B) causes depigmentation and/or lightening, protection and regeneration of the epidermis. An independent claim is also included for topical cosmetic or pharmaceutical compositions that contain (B). ACTIVITY : Dermatological. Human keratinocytes and melanocytes were seeded on to polycarbonate filters and grown for 10 days at an air/medium interface to produce a type VI (negroid) epidermis. Samples of this were incubated for an unspecified time with a cream (PXTS； designed for very dry skin) that contained 0.5 % of a lyophilizate of dedifferentiated cells of Crithmum maritimum. Intracellular melanin synthesis was then analyzed spectrometrically at 475 nm； absorbance was 0.160 in a negative control but 0.101 (37 % reduction) in the test sample. A further test showed a 32 % reduction in tyrosinase activity. MECHANISM OF ACTION : Blocking activity of tyrosinase (depigmentation and lightening)； scavenging free radicals (protective effect) and/or stimulating proliferation of cells in the basal layer and inhibiting epidermal differentiation (regenerative effect).
