Preliminary Study On The Components And Extraction Technology Of Main Flavonoids From Dalbergia Odorifera T. Chen Leaves

In the present study, genistein and biochanin A were obtained for the first time, and an RP-HPLC method was developed to simultaneously determined this two isoflavonoids and the process for the negative-pressure cavitation extraction of them was optimized with a three-variable,three-level Box-Behnken design, too. The results as follows:1. Four main componets were obtained from Dalbergia odorifera T. Chen leaves. In the process of extraction, separation and purification by macroporous absorption resin, silica gel column chromatography, recrystallization,etc, genistein and biochanin A were acquired for the first time comparing with the results of HPLC chromatograms, MS/MS and UV spectrograms. Dalbergia odorifera T. Chen leaves can be a new resource of genistein and biochanin A.2. An RP-HPLC method for simultaneous determination of genistein and biochanin A was developed as follows:An Jasco chromatography system with an UV detector was used. A HIQ Sil C18V column (250 mm×4.6 mm,5μm) at a temperature of 30℃was applied for the analyse. UV absorption was measured at 260 nm. The mobile phase consisted of (A)acetonitrile and (B)water using a gradient elution of 40%-60%A at 0-5 min,60%A at 5-15 min,60%A-40%A at 15-16 min,40%A at 16-21 min. The flow rate was 1 mL/min and aliquots of 10μL were injected.In the linearity range, this method was reliable for the analysis of genistein and biochanin A (R2≥0.9964, R.S.D.<3.0%), and the yields of genistein and biochanin A were 0.976 mg/g DW and 1.699 mg/g DW, respectively.3. Negative-pressure cavitation extraction conditions for genistein and biochanin A in Dalbergia odorifera T. Chen leaves were optimized, and the main parameters influencing the recovery were studied. The optimum extraction process was as follows: Extraction time:20 min Extraction solvent:ethanol-water(66:1, v/v) solution Ratio of liquid/solid:28:1(mL/g) Negative-pressure:-0.055 MPa Number of extraction cycles:3 times Under the above optimum conditions, the yields of genistein and biochanin A were 0.933 mg/g DW and 1.583 mg/g DW, recovery yields of genistein and biochanin A were 95.59% and 93.17%, R.S.D. of them were 1.34% and 1.04%, respectively.