All three different dosages of fGT treated mice showed dose-dependent favorable effects, and especially, fGT 100, 200 and 400 mg/kg treated HFD mice also showed significant and more favorable inhibitory activities against type II diabetes and related complications—including obesity, hyperlipidemia, hepatic steatosis, kidney failures and deterioration of the liver antioxidant defense system—as compared with those of GT 400 mg/kg treated mice, and also in hepatic GK, G6pase and PEPCK activities, respectively. The gene discussed is PCK2; the disease is fatty liver disease.