An estimate of total phenols in the t-butanol layer and aqueous layer was determined by using Folin- Ciocalteu reagent. Gallic acid was used as a standard for the experiment. Various concentrations of gallic acid were prepared in methanol (1–100 μg/mL). A cali bration curve of gallic acid was constructed. In brief, 0.2 mL of test sample and 0.2 mL of Folin- Ciocalteu reagent were mixed thoroughly. After 4 min, 1 mL of 15% Na2CO3 was added, and then the mixture was allowed to stand for 2 h at room temperature.