Antioxidant and Anti-Adipogenic Activities of Trapa japonica Shell Extract Cultivated in Korea

shell contains phenolic compounds such as tannins. Studies regarding the antioxidant and anti-adipogenic effects of shell cultivated in Korea are still unclear. Antioxidant and anti-adipogenic activities were measured by assays such as 2,2-diphenyl-1-picrylhydrazy (DPPH) radical scavenging activity, 2,2'-azinobis( 3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging activity, ferric reducing ability of plasma assay, reducing power, superoxide dismutase-like activity, and iron chelating ability in 3T3-L1 cells. We also measured the total phenol and flavonoids contents (TPC and TFC, respectively) in shell extract. Our results show that TPC and TFC of shell extract were 157.7±0.70 mg gallic acid equivalents/g and 25.0±1.95 mg quercetin equivalents/g, respectively. shell extract showed strong antioxidant activities in a dose-dependent manner in DPPH and ABTS radical scavenging activities and other methods. Especially, the whole antioxidant activity test of shell extract exhibited higher levels than that of butylated hydroxytoluene as a positive control. Furthermore, shell extract inhibited lipid accumulation and reactive oxygen species production during the differentiation of 3T3-L1 preadipocytes. shell extract possessed a significant antioxidant and anti-adipogenic property, which suggests its potential as a natural functional food ingredient.