[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
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
Total flavonoid glycoside was isolated from Ginkgo biloba Linn. leaf tablet and determined by RP-HPLC using quercetin as external standard. 4.6 mm×100 mm Spherisorb ODS column, mobile phase: V (CH\-\{3\}OH) ∶ V ...Total flavonoid glycoside was isolated from Ginkgo biloba Linn. leaf tablet and determined by RP-HPLC using quercetin as external standard. 4.6 mm×100 mm Spherisorb ODS column, mobile phase: V (CH\-\{3\}OH) ∶ V (0.3% H\-\{3\}PO\-\{4\})=40∶60, flow rate: 1 mL/min, detection: λ=370 nm. The sample was extracted with CH\-\{3\}OH by ultrasonic extraction and hydrolyzed with 25% HCl, then sample solution was diluted accurately to 50 mL. This experiment showed that this is a simple, accurate and precise method with the result of fine linearity, average recovery is 101.1% for quercetin, and RSD is 2.44%.展开更多
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 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Total flavonoid glycoside was isolated from Ginkgo biloba Linn. leaf tablet and determined by RP-HPLC using quercetin as external standard. 4.6 mm×100 mm Spherisorb ODS column, mobile phase: V (CH\-\{3\}OH) ∶ V (0.3% H\-\{3\}PO\-\{4\})=40∶60, flow rate: 1 mL/min, detection: λ=370 nm. The sample was extracted with CH\-\{3\}OH by ultrasonic extraction and hydrolyzed with 25% HCl, then sample solution was diluted accurately to 50 mL. This experiment showed that this is a simple, accurate and precise method with the result of fine linearity, average recovery is 101.1% for quercetin, and RSD is 2.44%.
