Analysis And Extraction Of Effective Components Of Eucalyptus Exserta

Eucalyptus exserta,one of the widely introduced Eucalypti in China,has broad application prospects.Volatile compounds and non-volatile compounds of Eucalyptus exserta were studied in this experiment.Volatile oil was obtained by steam distillation method.Water-soluble fraction was extracted by diethyl ether from distillation residual solution.Both of them were determined with GC-MS.Moreover,different detection methods of total polyphenols content were compared and chosen.The total polyphenols content of leaves,branches and fruits from Eucalyptus exserta were determined by the chosen method,respectively.At last,the anti-oxidant activities of Eucalyptus exserta extractions were evaluated in terms of DPPH· scavenging activity method and OH scavenging activity.The research contents and results are as follows:1.The extraction yield of essential oils from the leaves were 0.45%-0.99%(on fresh weight basis)at four seasons.The extraction yield of essential oils from the branches were 0.09%-0.16%(on fresh weight basis)at four seasons.The extraction yield of essential oils from the fruits were 0.21%-0.58%(on fresh weight basis)at spring,autumn and winter.In summer,Eucalyptus exserta was in the flowering period,the extraction yield of essential oils from the flowers,instead of fruits,was 0.58%.2.Total phenols were extracted from leaves,branches and fruits via conventional extract approach,respectively.Extractions were detected by precipitation reaction,Chromogenic reaction and UV spectroscopy in succession as qualitative analysis.The results showed that hydrolyzate of total phenols was gallic acid.Folin-Ciocalteu and Ferrous Tartrate method were used as quantitative analysis.By comparison,Ferrous Tartrate method was reasonable.The total polyphenols content of all samples were determined by Ferrous Tartrate method.3.The anti-oxidant activities of Eucalyptus exserta extractions were evaluated in terms of scavenging activity to DPPH· and ·OH.As results,the anti-oxidation of leaves,branches and fruits from Eucalyptus exserta were higher than Vitamin C in low concentration.When DPPH· as indicator,scavenging rate of distilled braches and fruits were higher than fresh ones.However,scavenging rate of distilled leaves was in reverse.When OH as indicator,scavenging rate of all samples slowly grew as the concentration increased due to the extractions were impure.However,scavenging rate of Vitamin C grew rapidly as the concentration increased.