Studies On Gingerols From Zingiber Officinale Rosc

Zingiberis officinale Rosc.,a well-known medicinal plant, is widely used for treatment of stomachic diseases, inflammation,different body pains,trauma,bleeding caused by internal and external injury etc.Also,it was used as a tonic and haemostatic agent.Due to the demand for its important medicinal use in China,it was largely cultivated in Sichuan and Guizhou Provinces.The pungent compounds in this plant have been reported more before,but the RP-HPLC determinations for main Gingerols in Zingiber officinale Rosc.have been reported fewer.For the sake of the better use of this herb medicine,this paper describes the isolation,structural determinations and the measurement of the main gingerols from the Zingiber officinale Rosc.Extraction and SeparationDried Zingiber officinale Rosc.(2kg)were extracted by heat reflux in methanol(15L,12L,10L,respectively)for three times(2h,1.5h,1h,respectively).The extraction was subjected to silica gel column and ODS column eluted repeatedly to afford compoundsâ… (5.1g),â…¡(1.9g),â…¢(2.1g),â…¡(104mg),â…¤(20mg)andâ…¥(8mg)。Compoundsâ… -â…¥was identified respectively by UV,IR,MS and 1DNMR as 6-gingerol,8-gingerol,10-gingerol,4-gingerol,6-shogaol and zingerone.Determination of gingerols in Zingiber officinale Rosc.In this paper,we present a more sensitive quantificational method by HPLC for measuring the main gingerols(Ⅰ～Ⅲ)in Rhizoma zingiber.Separation was carried out on Agilent Hc-C₈ column(150 mm×4.6 mm,5μm).Solvent A was acetonitrile,and solvent B was containing 0.1%acetic acid.A linear solvent gradient was used,0-23min,43%A;23-50 min,65%A;50-60 min,80%A.The flow rate was 1.0 mL/min at 30℃,and the detector was set at 275 nm.Conclusion:â…°The linearity was in the range of 0.5-20μg for 6-,8-,10-gingerol,and all the correlation coefficients were 0.9999(n=6).Y=1.024×10⁴X+15.35 r=0.9999Y=9.287×10³X2+6.540 r=0.9999Y=8.818×10³X+8.230 r=0.9999â…±We injected 6-,8-,10-gingerol into HPLC six times and the results of precision tests is RSD＜1%.â…²We measured the contents of 6-,8-,10-gingereol from Rhizoma zingiber,and the results are RSD＜3%respectively.â…³When the concentration of 6-,8-,10-gingerol diluted to 1×l0^-4,1×10^-5,1×10^-6mg/ml,S/N=3,So the detectability are 0.02,2,0.2ng respectively。ⅴThe stability of 6-,8-,10-gingerol is good in eight hours because the results are RSD＜2%.â…µThe average recoveries(n=6)for 6-,8-,10-gingerol are 100.6%(RSD=1.3%),101.6%(RSD=1.6%)and 99.8% (RSD=2.4%)(n=6)respectively.â…¶The content of 6-,8-,10-gingerol in the Zingibe officinale Rosc.purchased from jilin pharmacy weredetermined by the above method,the results showedthat their contents were different.The content of 6-gingerol is higher than 8-gingerol and 10-gingerol.The average contents of 6-,8-,10-gingerol were 0.51%,0.19%,and 0.21% respectively.The results of this paper can offer a new item on content determination for establishment of quality stand-ards and provide science foundation of the developmentand utilization of Zingiber officinale Rosc.