Study On Chemical Constituents From Panax Japonicus C. A. Mey. Var. Major (Burk.) C. Y. Wu Et K. M. Feng

Pearl ginseng（Panax japonicus C. A. Mey. var. major（Burk.）C. Y. Wu et K. M.Feng）is perennial herbs which belonging to Panax family. Pearl ginseng containsmany types of chemical constituents, including saponins, essential oils, carbohydrates,amino acids, trace elements and so on. Pharmacological studies have shown that pearlginseng has anti-tumor, anti-inflammatory, sedative, analgesic, anti-leukopenia andother effects.Eight compounds were isolated from the pearl ginseng in this paper. According totheir physical, chemical properties and spectra characteristicts of IR, MS and NMR ,the chemical structures of the 7 compounds were identified as 24（R）-majorosideR1(pg1),6-O-[β-D- glucopyranosyl-(1â†'2)-β-D-glucopyranosyl]-20-O-[β-D-glucopyranosyl-(1â†'4)-β-D-glucopyranosyl]-20(S)-protopanaxatriol(pg2),6″-acetyl-ginsenoside-Rd(pg3), ginsenoside Rf (pg4), Chikusetsusaponin-IVa(pg5),ginsenoside Rd(pg6), Chikusetsusaponin-V(pg7). Among them, 24(R)- majoroside R1and 6-O-[β-D-glucopyranosyl-(1â†'2)-β-D-glucopyranosyl]-20-O-[β-D-glucopyranosyl-(1â†'4)-β-D-glucopyranosyl]-20(S)-protopanaxatriol are newcompounds; 6″-acetyl-ginsenoside-Rd and ginsenoside Rf are the first time isolatedfrom pearl ginseng.Determination method by HPLC-ELSD was established to analysis 24(R) -majoroside R1in the Pearl ginseng in this paper.Extraction, separation and identificationSeven Kg dried roots of pearl ginseng were crushed and extracted by heat refluxin 80% ethanol (the volume fraction) three times (1.5h, 1.0h,1.0h respectively).Thecombined extract was evaporated to dryness under reduced pressure and 1.4Kg of extracts were obtained. By using silica gel, ODS column chromatography repeatedlywith ethylacetate, chloroform, methanol, ethanol and water in various ratios were usedas the mobile phase. Seven compounds previously described were isolated. Accordingto their physical, chemical properties and spectra characteristicts of IR, MS and NMR,the chemical structures of the 7 compounds were identified after comparing with theliterature reports.All the isolated compounds were elucidated as 24（R）- majoroside R1(pg1),6-O-[β-D-glucopyranosyl-(1â†'2)-β-D-glucopyranosyl]-20-O-[β-D-glucopyranosyl-(1â†'4)-β-D-glucopyranosyl]-20(S)-protopanaxatriol (pg2),6″-acetyl-ginsenoside-Rd (pg3),ginsenoside Rf (pg4), Chikusetsusaponin-IVa (pg5), ginsenoside Rd (pg6),Chikusetsusaponin-V (pg7).Determination of 24（R）- majoroside R1in Pearl ginseng by HPLC-ELSD1. Chromatographic and detector conditionsAgilent1200 HPLC, Alltech2000 ELSD; Zorbax SB-C18Column（ODS,4.6×250mm , 5μm. The mobile phase is methanol-water (58:42), flow rate wasadjusted to 1.0mL.min-1, the column temperature was 25℃; ELSD drift tubetemperature degree was set at 85℃; Carrier gas flow rate was 1.94bar; Amplificationfactor was1.0 with impactor in closed state.2. Methodology Studyâ… Linear relationshipPg1 In the range of 0.4 -20.0μg, common logarithm of peak area and commonlogarithm of the sample amount gave a good linearity. The regression and correlationcoefficent are showed as follows.lgS=1.3177lgm + 1.7605，r = 0.9993â…¡Precision experimentPg1 peak area RSD was 1.35% by determinating the same control solution 6 times.The results show that the method has a good precision.â…¢Repeatability experiment Pg1 content RSD was 0.96% by determinating the 6 copies test sample solution;the results showed that the method had a good reproducibility.â…£Stability experimentPg1 peak area RSD was 1.71% by determinating sample solution during 10 hours;the results showed that the sample solution is stable during10 hours.â…¤Recovery experimentIn this paper, the average recovery of 24(R) - majoroside R1was 98.7% (RSD1.28%).After determination, the content of 24(R) - majoroside R1in pearl ginseng was0.0453 % in average.In this paper, the chemical constituents of pearl ginseng were further studied, thedetermination method to analysis 24(R) - majoroside R1in this plant was establishedby HPLC-ELSD method. The results of this paper provided a theoretical support forfurther study and a scientific basis for development and utilization of pearl ginseng.