Abstract:

【Objective】 The aim of this study is to investigate the effect of different concentrations of sporamin on differentiation and proliferation of 3T3-L1 preadipocytes, providing a theoretical basis for the development of prevention and treatment of obesity and anti-diabetes reagent in food industry. 【Method】 Isolation and purification of sporamin from sweet potato 55-2 was performed by ammonium sulphate precipitation in combination with ion-exchange-, gel filtration chromatography. With berberine as a positive control, different concentrations of sporamin (0, 0.025, 0.125, 0.250, 0.500 and 1.000 mg?ml-1, respectively) were used to treat 3T3-L1 preadipocytes. Intracellular fat accumulation and the degree of adipogenesis were observed using oil red O staining and quantified by colorimetry. Preadipocytes differentiation was measured by MTT spectrophotometry. 【Result】 Two sporamin proteins which were separated into sporamin A (31 kD) and sporamin B (22 kD) could be purified by ion-Exchange-, gel filtration chromatography. After being treated by different sporamin concentrations, the differentiation of 3T3-L1 preadipocytes was significantly inhibited compared with control. When the concentration of sporamin solution was 0.500 mg?ml-1, the accumulation of lipid droplets within the cells were obviously decreased and the optical density (OD) value of the solution from destained Oil Red O reached to 0.35, which was the lowest value (P＜0.05). The proliferation of 3T3-L1 preadipocytes was significantly inhibited by treating at higher sporamin concentration. In addition, the restrictive effect was more obvious with the prolonging of treatment time (P＜0.05). 【Conclusion】Differentiation and proliferation of 3T3-L1 preadipocytes could be inhibited significantly by addition of higher concentration sporamin. It is, therefore, suggested that sporamin is effective for weight loss.

Key words: sweetpotato, sporamin, 3T3-L1 preadipocytes