In vitro: Each 50 ml of the aspirated fat from healthy women with age from 20s to 40s were transferred into 60 ml syringes. We divided them into six groups by the different processing method. We removed water and blood, oil naturally separated by gravity for 5 min after harvesting or washing from every syringe (primary removal of impurities) in every group before starting these experiments. For the A group named as a Crude harvested fat, we left the 50 ml lipoaspirates at room temperature for 5 min, induced to be naturally separated into fat, blood fluid and oil portions and we discarded the impurities oil, blood and fluid portions. For the B group named as a Washed Fat, the 50 ml lipoaspirates was washed with DPBS at 1:1 ratio three times and only the fat portion is harvested through removal of naturally separated impurities as above. For the C group as a Simple Centrifugation, we centrifuged at 200 g (1,020 rpm) for 3 min after a primary removal of impurities. For the D group as a Squeezing centrifugation, we centrifuged the 50 ml crude fat tissues in the 50 ml fat processing unit syringe with 100 μm mesh piston (50 ml FPU™, Medikan Co Ltd., S. Korea) at 3,500 rpm (1,924 g) regarding the all different spinning diameter within a long syringe) for 5 min. For the E group as a hand squeezer (Lipo Squeezer™, Medikan Co Ltd., S. Korea), we condensed more with two times squeezing, first with 1.18 mesh piston and then with 0.8 mesh again, and finally centrifuged with a fat processing centrifuge (Lipokit™, Medikan Co Ltd., S. Korea) (Fig. 13.2). For the last F group, a fat mincing micronizer (Filler Geller™, Medikan Co Ltd., S. Korea), we centrifuged first, micronized or minced with a fat mincing micronizer (Filler Geller™, Medikan Co Ltd., S. Korea) at speed level 6 for 9 s and finally centrifuged again. From six groups, we used the equal volume of fat, treated with 0.2 % collagenase, incubated for 30 min at 37 °C, subsequently washed with DPBS three times and finally counted the cell numbers.

In vivo: We used an 8th week aged female nude mouse and inject 0.5 ml fat from each 6 group into both its hypoderms with 21G needle. We took fat graft at 4th and 8th weeks respectively, measured each weight and specific gravity and finally analyzed the physiological structures of graft tissue using Masson Trichrome (M.T.) dyeing method.