ABSTRACT
Objective To establish a thin-layer chrometograrrgy(TLC)method for the identification of quercetin and chloro?genic acid in Ramulus mori,and to screen their antioxidant activity. Methods The quercetin and chlorogenic acid were extracted by ultrasonic method with methanol as a solvent. The effect of different developed system,reagent,temperature,view methods and differ?ent silica gel plate on the TLC of quercetin and chlorogenic acid in Ramulus mori were tested to select the best TLC conditions. The antioxidant activity of quercetin and chlorogenic acid was screened with DPPH as a reagent. Results The ethyl acetate∶water∶formic acid∶toluene(17∶2∶2∶0.8)was used as a developing system and 1%AlCl3 as a chromogenic reagent. Quercetin and chlorogenic acid in Ramulus mori were identified under 366 nm,with blue and blue-green spots on silica gel G plate,and yellowish spots under purple background by the test of TLC-bioautography. Both were proven to have antioxidant activity. Conclusion The method is simple,accu?rate and reliable,and can be used for quality control of Ramulus mori.
ABSTRACT
Objective To establish the methods for identification and quantification ofγ-aminobutyric acid(GABA)in Ramu?lus Mori by TLC and HPLC. Methods GABA was extracted by ultrasonic method with ethanol as solvent. The sample was applied on an efficient silica gel G plate with n-butanol-acetic acid-water(4∶2.2∶1)as the developing system,and ninhydrin was used as chromog?enie reagent. The content ofγ-GABA was determined by HPLC. The separation was carried out on a ODS(4.6 mm × 250 mm,5μm) column with phosphate buffered solution(pH=6.8)-methanol as a mobile phase with gradient elution,flow rate was 1.0 ml/min,the de?tection wavelength was 335 nm. Results The TLC spots of GABA in Ramulus Mori were clear with good separation. The assay of GA?BA was linear in the range of 1.006-84.504μg/ml and correlation coefficient was 0.9994. Conclusion The methods are simple,ac?curate and reproducible which are valuable to identify Ramulus Mori.