Ginkgo flavonoids are one of the most effective medicinal components extracted from leaves of Ginkgo biloba L.According to the physical and chemical properties of ginkgo flavonoids,they can be separated and purified b...Ginkgo flavonoids are one of the most effective medicinal components extracted from leaves of Ginkgo biloba L.According to the physical and chemical properties of ginkgo flavonoids,they can be separated and purified by resin adsorption,supercritical extraction and solvent methods.Previous studies have proved that ginkgo flavonoids have pharmacological functions in promoting blood circulation,anti-oxidation,anti-aging,improving memory,anti-tumor and liver protection,etc.Ginkgo flavonoids have been used clinically to treat angina pectoris,coronary heart disease,myocardial ischemia,hypertension,hyperlipidemia,diabetes,alzheimer's disease,atherosclerosis,gastric cancer and ovarian malignancy and other difficult miscellaneous diseases.展开更多
[Objectives]This study was conducted to study the extraction process and the content determination of flavonoids in ginkgo( Ginkgo biloba L.) leaves.[Methods]Ethanol extraction and methanol extraction of total flavono...[Objectives]This study was conducted to study the extraction process and the content determination of flavonoids in ginkgo( Ginkgo biloba L.) leaves.[Methods]Ethanol extraction and methanol extraction of total flavonoids in ginkgo leaves were studied,and the optimal extraction conditions for flavonoids were determined by orthogonal test; and with quercetin as reference substance,total flavonoid content in ginkgo leaves was determined by UV spectrophotometry.[Results]The optimal extraction process was 4 h of Soxhlet extraction with methanol; and the total flavonoid contents had a good linear relation in the range of 0. 006 5-0. 039 mg/ml( R^2= 0. 999 9),the average content was stabilized at 1. 135%,and the average recovery of the method was 102. 0%. [Conclusions]This study selected the optimal extraction process for total flavonoids in ginkgo leaves. The test method is simple with high accuracy and precision,and is suitable for the extraction and determination of total flavonoids in ginkgo leaves.展开更多
[Objectives]This study was conducted to determine the content of total flavonoids in ginkgo ( Ginkgo biloba L.) leaves.[Methods]The content of total flavonoids from ginkgo leaves was determined by reversed phase-high ...[Objectives]This study was conducted to determine the content of total flavonoids in ginkgo ( Ginkgo biloba L.) leaves.[Methods]The content of total flavonoids from ginkgo leaves was determined by reversed phase-high performance liquid chromatography (RP-HPLC).The flavonoid glycosides were first extracted with methanol,and hydrolyzed with hydrochloric acid solution to prepare a test solution.Platisil ODS C18 column (150 mm×4.6 mm,5 μm) and the mobile phase V methanol ∶ V water (0.4% phosphoric acid solution)=85∶ 15 were selected for HPLC separation.The HPLC separation was performed with the column at a column temperature of 25℃ using the mobile phase at a flow rate of 1 ml/min.The sample size was 10 μl,and detection was performed with an Agilent HPLC ultraviolet detector at 360 nm.[Results]The reference substance,quercetin,had good linearity in the range of 0.002 6-0.052 0 g/L,with a correlation coefficient of 0.999 7;and the RSD was 1.26%.[Conclusions]The determination method has rapid and simple operation with accurate results and is good in repeatability.This method is suitable for the determination of content of total flavonoids in ginkgo leaves.展开更多
By optimizing the separation and analytical conditions, a reliable, simple and accurate high-performance liquid chromatography（HPLC） method coupled with ultraviolet（UV） and evaporative light scattering detector（E...By optimizing the separation and analytical conditions, a reliable, simple and accurate high-performance liquid chromatography（HPLC） method coupled with ultraviolet（UV） and evaporative light scattering detector（ELSD） was developed for the simultaneous determination of lactones and flavonoid, that is, bilobalide, ginkgolide A, ginkgolide B, and rutin, in more than 10 batches of Ginkgo biloba tablets from different pharmaceutical companies. The method could also be applied to fingerprint research, for a more general evaluation of the quality of this preparation. The separation of the components was achieved on a Hanbon C18 column with gradient elution using water and methanol containing 0.1% trifluoroacetic acid（TFA）. The column temperature was 30 ℃ and the flow-rate of the mobile phase was 0.6 mL/min. The drift tube temperature of the ELSD was set at 100 ℃, and the nitrogen flow-rate was 2 L/min. Good linear relationships were shown with correlation coefficients for analytes exceeding 0.9913. The limits of detection（LODs, S/N=3） and the limits of quantitation（LOQs, S/N=10） were 0.00887-0.0508 μg/μL and 0.0171- 0.0636 μg/μL, respectively, on the column. The relative standard deviations（RSD） of the analytes were less than 3.61% for intraday and 3.70% for interday, respectively. The average recovery rates obtained were in the range of （97.3±4.3）% to （101.9±3.1）% for all the compounds. The results of quantitative and fingerprint analysis proved that the contents of the components were totally similar in the preparation of Ginkgo biloba tablets from the same pharmaceutical company; whereas, they varied significantly in the preparations of Ginkgo biloba tablets from different companies.展开更多
Separation of Ginkgo flavonoids using simulated moving bed chromatography to replace the batch chromatography is discussed.The product of higher purity is obtained,and in this process,the yield of product increased an...Separation of Ginkgo flavonoids using simulated moving bed chromatography to replace the batch chromatography is discussed.The product of higher purity is obtained,and in this process,the yield of product increased and cost decreased.Furthermore,this process is very clean.展开更多
基金Natural Science Foundation Project of Hubei Province(2018CFB406)Talent Introduction Project of Hubei Polytechnic University(19XJK02R)Hubei Provincial Education Department Project(Q20204508).
文摘Ginkgo flavonoids are one of the most effective medicinal components extracted from leaves of Ginkgo biloba L.According to the physical and chemical properties of ginkgo flavonoids,they can be separated and purified by resin adsorption,supercritical extraction and solvent methods.Previous studies have proved that ginkgo flavonoids have pharmacological functions in promoting blood circulation,anti-oxidation,anti-aging,improving memory,anti-tumor and liver protection,etc.Ginkgo flavonoids have been used clinically to treat angina pectoris,coronary heart disease,myocardial ischemia,hypertension,hyperlipidemia,diabetes,alzheimer's disease,atherosclerosis,gastric cancer and ovarian malignancy and other difficult miscellaneous diseases.
基金Supported by Guilin Science and Technology Bureau Project(20100305)Guangxi"2011 Collaborative Innovation Center"-Zhuang Yao Medicine Collaborative Innovation Center Project(G2013[20])Special Fund for Traditional Medical Science and Technology of Department of Public Health of Guangxi Zhuang Autonomous Region(GZMZ1212)
文摘[Objectives]This study was conducted to study the extraction process and the content determination of flavonoids in ginkgo( Ginkgo biloba L.) leaves.[Methods]Ethanol extraction and methanol extraction of total flavonoids in ginkgo leaves were studied,and the optimal extraction conditions for flavonoids were determined by orthogonal test; and with quercetin as reference substance,total flavonoid content in ginkgo leaves was determined by UV spectrophotometry.[Results]The optimal extraction process was 4 h of Soxhlet extraction with methanol; and the total flavonoid contents had a good linear relation in the range of 0. 006 5-0. 039 mg/ml( R^2= 0. 999 9),the average content was stabilized at 1. 135%,and the average recovery of the method was 102. 0%. [Conclusions]This study selected the optimal extraction process for total flavonoids in ginkgo leaves. The test method is simple with high accuracy and precision,and is suitable for the extraction and determination of total flavonoids in ginkgo leaves.
基金Supported by Guilin Science and Technology Bureau Project(20100305)Guangxi "2011 Collaborative Innovation Center"-Zhuang Yao Medicine Collaborative Innovation Center Project(G2013[20])
文摘[Objectives]This study was conducted to determine the content of total flavonoids in ginkgo ( Ginkgo biloba L.) leaves.[Methods]The content of total flavonoids from ginkgo leaves was determined by reversed phase-high performance liquid chromatography (RP-HPLC).The flavonoid glycosides were first extracted with methanol,and hydrolyzed with hydrochloric acid solution to prepare a test solution.Platisil ODS C18 column (150 mm×4.6 mm,5 μm) and the mobile phase V methanol ∶ V water (0.4% phosphoric acid solution)=85∶ 15 were selected for HPLC separation.The HPLC separation was performed with the column at a column temperature of 25℃ using the mobile phase at a flow rate of 1 ml/min.The sample size was 10 μl,and detection was performed with an Agilent HPLC ultraviolet detector at 360 nm.[Results]The reference substance,quercetin,had good linearity in the range of 0.002 6-0.052 0 g/L,with a correlation coefficient of 0.999 7;and the RSD was 1.26%.[Conclusions]The determination method has rapid and simple operation with accurate results and is good in repeatability.This method is suitable for the determination of content of total flavonoids in ginkgo leaves.
基金Supported by the Program for New Century Excellent Talents in University of China(No.NCET-06-0515).
文摘By optimizing the separation and analytical conditions, a reliable, simple and accurate high-performance liquid chromatography（HPLC） method coupled with ultraviolet（UV） and evaporative light scattering detector（ELSD） was developed for the simultaneous determination of lactones and flavonoid, that is, bilobalide, ginkgolide A, ginkgolide B, and rutin, in more than 10 batches of Ginkgo biloba tablets from different pharmaceutical companies. The method could also be applied to fingerprint research, for a more general evaluation of the quality of this preparation. The separation of the components was achieved on a Hanbon C18 column with gradient elution using water and methanol containing 0.1% trifluoroacetic acid（TFA）. The column temperature was 30 ℃ and the flow-rate of the mobile phase was 0.6 mL/min. The drift tube temperature of the ELSD was set at 100 ℃, and the nitrogen flow-rate was 2 L/min. Good linear relationships were shown with correlation coefficients for analytes exceeding 0.9913. The limits of detection（LODs, S/N=3） and the limits of quantitation（LOQs, S/N=10） were 0.00887-0.0508 μg/μL and 0.0171- 0.0636 μg/μL, respectively, on the column. The relative standard deviations（RSD） of the analytes were less than 3.61% for intraday and 3.70% for interday, respectively. The average recovery rates obtained were in the range of （97.3±4.3）% to （101.9±3.1）% for all the compounds. The results of quantitative and fingerprint analysis proved that the contents of the components were totally similar in the preparation of Ginkgo biloba tablets from the same pharmaceutical company; whereas, they varied significantly in the preparations of Ginkgo biloba tablets from different companies.
文摘Separation of Ginkgo flavonoids using simulated moving bed chromatography to replace the batch chromatography is discussed.The product of higher purity is obtained,and in this process,the yield of product increased and cost decreased.Furthermore,this process is very clean.
