Optimization of ultrasonic extraction of total flavonoids from Tussilago farfara L. using response surface methodology.

In this work, ultrasound technology was used for the extraction of total flavonoids from Tussilago farfara L. Response surface methodology (RSM), based on a Box-Behnken design (BBD), was used to optimize the effects of processing parameters on total flavonoids yields. The parameters were ultrasonic frequency (X1), extraction time (X2) and ratio of liquid to solid (X3). The statistical analysis indicated that the parameters of ultrasonic power and ratio of liquid to solid, and the square effects among them had significant effects on the yield of flavonoids from Tussilago farfara L. The interaction between ultrasonic power and extraction time, and ultrasonic power and ratio of liquid to solid also caused significant effects on the yields. The optimum extraction conditions were determined as follows: ultrasonic power 420 W, extraction time 30 min, ratio of liquid to solid 25 mL/g. Under these conditions, the experimental yield 6.59 +/- 0.061% agreed closely with the predicted yield (6.64%).

[Capillary electrophoresis with field-enhanced stacking for determination of water-soluble active principles in Salvia miltiorrhiza var. miltiorrhiza f. alba].

A simple and sensitive capillary electrophoresis method with field-enhanced stacking concentration for the analysis of protocatechuic aldehyde, protocatechuic acid, danshensu, rosmarinic acid and salvianolic acid B in Salvia miltiorrhiza var. miltiorrhiza f. alba was developed. The separation was achieved with a fused-silica capillary (75 microm x 50.2 cm, effective length was 40 cm) and a running buffer 15 mmol x L(-1) borax (pH 10.0) containing 20% CH3 OH. The UV detection wavelength was 210 nm. The applied voltage was 28 kV, and the cartridge temperature was 25 degrees C. Water plug was introduced from the anode by 0.5 psi x 4 s before injection. Sample was injected by electrokinetic injection - 8 kV x 3 s. The linear range of protocatechuic aldehyde is 3.0-60.00 mg x L(-1) (R2 = 0.999 8); that of protocatechuic acid, danshensu, rosmarinic acid and salvianolic acid B are 1.0-20.00 mg x L(-1) (R2 are 0.999 1, 0.999 4, 0.998 9 and 0.999 8, respectively), and the limits of detection of five analyts are 0.55, 0.40, 0.25, 0.32, 0.38 microg x L(-1), respectively, Stacking factor is higher and precision is satisfactory. The recoveries ranges were from 97.3% to 99.8%. The proposed method was used to determine the protocatechuic aldehyde, protocatechuic acid, danshensu, rosmarinic acid and salvianolic acid B in S. miltiorrhiza var. miltiorrhiza f. alba. The proposed method is simple, rapid, accurate and high sensitivity, and can be used to control of the quality of S. miltiorrhiza var. miltiorrhiza f. alba.

[Determination of tetrandrine and fangchinoline in Radix Stephaniae tetrandrae and its preparation by nonaqueous capillary chromatography].

OBJECTIVE: To establish a new method for the determination of fangchinoline and tetrandrine in Stephania tetrandra and Fengtongan capsule by noanqueous capillary electrophoresis. METHOD: Separation was carried out in an uncoated fused capillary (50 cm x 75 microm i.d.) with a running buffer containing 50 mmol x L(-1) ammonium acetate, 1.0% acetic acid and 20% acetonitrile in methanol. A separation voltage of 20 kV and a UV detector wavelength at 214 nm were adopted. Sample was introduced from the anode. RESULT: The calibration ranges were 1.00, 500 mg x L(-1) for both analytes. Under the optimum conditions, the relative standard deviation (RSD, n = 6) for the migration time of each analyte were 0.09%, 1.9% (intra-day) and 0.63%, 1.9% (inter-day); The RSD for the peak area of each analyte were 0.45%, 5.9% (intra-day) and 2.3%, 5.6% (inter-day), respectively. The contents of the analytes were determined easily with average recoveries 102% for fangchinoline and 105% for tetrandrine in S. tetrandra and 94.6% for fangchinoline and 98.7% for tetrandrine in Fengtongan capsules, respectively. CONCLUSION: The proposed method is simple, rapid, accurate and higher repeatable, and can be used to control of the quality of S. tetrandra and Fengtongan capsules.