Study On Extraction And Enrichment Of Main Taxanes From Needles Of Taxus Chinese

In this work,renewable needles of Taxus chinese as a kind of woody medicinal plant resources were selected as the materials.A two-phase system formed by green and recyclable menthol-based deep eutectic solvent（DES）aqueous was designed and synthesized,and then applied successfully for green and efficient extraction of seven target taxanes functional ingredients from Taxus chinese needles.Series of single-factor experiments were designed to optimize the extraction procedure about ultrasound-assisted extraction of deep eutectic solvent aqueous two-phase system.Meanwhile,main taxanes in the extract were enriched and separated based on the separation characteristic of two-phase solvent.The results were as follows:1. A HPLC method was established for the simultaneous analysis and detection of seven functional taxanes in Taxus chinese needles,the HPLC chromatographic conditions were as follows:Chromatographic column:Phenomenex-Gemini 5μC₁₈（250 mm×4.6 mm,5μm）,detected wavelength:234 nm,injected volume:20μL,column temperature:35°C,flow velocity:1.0 m L/min.mobile phases:water（A）-acetonitrile（B）.The separation was conducted by the following elution conditions:0-5 min,37%-37%B;5-12 min,37%-45%B;12-25 min,45%-60%B.The method established could achieve quantitation of seven taxanes within 25 min,which possessed better linearity（R2>0.998）,precision and repeatability（RSD<4.00%）and recovery（90.26-109.00%）.2. A two-phase system formed by menthol/1-butanol DES and aqueous was founded,and then the extraction procedure of seven functional taxanes in Taxus chinese needles about ultrasound-assisted deep eutectic solvent aqueous two-phase system extraction was designed and optimized.The optimal process parameters were as follows:Deep eutectic solvent（DES）:menthol/1-butanol=1:1（mol/mol）,Water content:50%,Solid-liquid ratio:1:30 g/m L,Extraction time:30 min,Ultrasound power:250 W.Under the optimal conditions,the extraction yields of 10-deacetylbaccatin III（10-DAB III）,baccatine III,7-xylosyl-10-deacetyltaxol,10-deacetyltaxol,cephalomannine,7-epi-10-deacetyltaxol,paclitaxel were626.44μg/g,120.48μg/g,546.95μg/g,236.49μg/g,105.69μg/g,166.44μg/g and 162.75μg/g,respectively.The extraction yields of DES aqueous two-phase system increased 0.27-1.65 folds than that of conventional organic solvents extraction such as methanol,ethanol and 80%ethanol.3. The recovery of seven main taxanes from DES and the recycling of DES components were obtained by the ingenious vacuum installation combined with ice salt bath condensation technology.The results were as follows:The recovery of seven target taxanes ranged from 95.31%to 99.28%.Furthermore,the menthol-based DES aqueous could be recycled at least three times.The recoveries of target ingredient could reach more than 95.01%,and the recovery of menthol and 1-butanol were 84.79%and 68.90%,respectively after reused three times.In this paper,an accurate and rapid method was developed for the analysis and detection of taxanes in the Taxus chinensis needles.In addition,a novel DES aqueous two-phase system for the extraction and enrichment integration processes of taxanes was established,which is green,eco-friendly,high extraction yields,simple operation and low cost.This study provided a favorable scientific basis for the sustainable development and utilization of Taxus renewable resources.At the same time,it is of great significance for high value-added green processing and high-value utilization of forest resources in China.