Preparation and method for producing a preparation or a tissue derivative that include mesenchymal stem cells, to be used in cellular therapy, for cosmetic treatments, for replacing a tissue or an organ, or inducing or accelerating tissue repair or regeneration. The method includes the steps of extracting tissue containing mesenchymal stem cells, such as adipose tissue, from a cadaveric donor by liposuction or by surgical removal of parts of adipose tissue, and mechanically treating tissue to provide a fluid component, having an oily component, a blood component and/or a sterile solution, and a solid component having cell fragments, cells and one or more cell macro-agglomerates of heterogeneous sizes, thereby separating and removing the fluid component from the solid component, which generates an emulsion of fluid components.
