Abstract:Several antioxidant models has been studied and optimized of the Nelumbo nucifera Gaertn in this article. First, a new spectrophotometric method for the determination of the hydro- xyl radical ·OH produced by Fenton reaction has been proposed. The hydroxyl radical ·OH and methyl violet react at pH=3.5. The change in absorbance, corresponding to color intensity chan- ge of methyl violet can be measured at λ=580nm, so the amount of ·OH can be determined indir- ectly. The activity of medicament will be appraised.In condition, when the concentration of the polysaccharides from embryo of the seeds of Nelumbo nucifera Gaertn is 20mg/mL, scavenging achieves 48.83%. In the experiment of athanol and acetone extracts, scavenging are 91.36%, 78.06%.A method of pyrogallic has been proposed.At pH=8.2 ,the pyrogallic is oxidated to rele- asing the O2·-,producing coloured substance. When the antioxidant existences, may eliminates the O2·-, prevents the substance accumulating. the absorption of the solution weakens at λ=320 nm. When the concentration of the polysaccharides from embryo of the seeds of Nelumbo nucife- ra Gaertn is 25mg/mL, scavenging is 22.98%. In the experiment of athanol and acetone extracts, scaveng- ing are 22.80%, 44.86%.In DPPH model,when the concentration is 25mg/mL, scaveng- ing is 30.00%. Through this experiment,we may know that the extracts of the seeds of Nelumbo nucifera Gaertn has the antioxidant ability. It will provide a certain method for producing the natrue antioxidant.
Key words:Extracts from embryo of the seeds of Nelumbo nucifera Gaertn; antioxidant activity; Fenton reaction; Pyrogallic; DPPH model