Abstract:
Nelumbo nucifera stamens have been used in traditional Thai medicine for a long time. This study was carried out to develop the pharmacognostic specifications by qualitative and quantitative analyses as well as kaempferol contents of Nelumbo nucifera stamens. The samples were collected from 15 different sources throughout Thailand. Macroscopic and microscopic characteristics of crude drug were illustrated. The physicochemical parameters of Nelumbo nucifera stamens including loss on drying, total ash, acid-insoluble ash, water soluble extractives, ethanol soluble extractives and moisture were found to be 8.93±0.24, 5.23±0.12, 0.91±0.17, 10.91±0.37, 10.31±0.31 and 9.89±0.22 % by weight, respectively. Kaempferol in ethanolic extract of Nelumbo nucifera stamens were analyzed by thin layer chromatography (TLC) using silica gel 60 GF254 as stationary phase. Toluene, ethyl acetate, chloroform and formic acid (5:4:1:1) were used as mobile phase. The kaempferol contents were evaluated by TLC-densitometry with winCATS software and TLC-image analysis using imageJ software. The kaempferol contents in Nelumbo nucifera stamen crude drugs were found to be 0.041±0.013 and 0.045±0.016 g/100 g by those methods respectively. It was found that kaempferol contents by both methods were not statistically significant different by paired t-test (p>0.05). The method validations were investigated according to ICH guideline. The free radical scavenging potentials of the ethanolic extract of Nelumbo nucifera stamens were demonstrated with the IC50 of 27.31 µg/ml for DPPH and 28.37 mg/ml for nitric oxide. This study provided scientific evidences for identification, authentication and quality control of Nelumbo nucifera stamens crude drug.
