We previously developed an HPLC method for determination of lanatoside C, digoxin and α-acetyldigoxin in digitalis glycosides isolated from Digitalis lanata leaves. Here, we present an improved HPLC-UV method to dete...We previously developed an HPLC method for determination of lanatoside C, digoxin and α-acetyldigoxin in digitalis glycosides isolated from Digitalis lanata leaves. Here, we present an improved HPLC-UV method to determine those compounds and deslanoside. We used the improved method to examine the effects of various pretreatments on the amounts of the four compounds isolated from the leaves, with the aim of maximizing the yield of digoxin. Leaves were extracted with 50% methanol, followed by clean-up on a Sep-Pak C18 cartridge prior to HPLC analysis. The amounts of lanatoside C, digoxin and α-acetyldigoxin per 100 mg of the leaves without pretreatment were 115.6, 7.45 and 23.8 μg, respectively (deslanoside was not detected). Pretreatment with acetic acid, which activated deglucosylation mediated by digilanidase present in the leaves, increased the amounts of digoxin and α-acetyldigoxin, while lanatoside C and deslanoside were not detected. Pretreatment with sodium methoxide, which hydrolyzed lanatoside C to deslanoside, increased the yields of deslanoside and digoxin, while lanatoside C and α-acetyldigoxin were not detected. The combination of both pretreatments afforded only digoxin in a yield of 115.1 μg/100 mg leaves. Use of the combined pretreatments appears to be effective for maximizing the yield of digoxin from the leaves.展开更多
Objective: Digoxin is a therapeutic cardenolide widely used to treat various heart conditions such as atrial flutter, atrial fibrillation and heart failure in both Western as well as Chinese medicine. Digoxin is extra...Objective: Digoxin is a therapeutic cardenolide widely used to treat various heart conditions such as atrial flutter, atrial fibrillation and heart failure in both Western as well as Chinese medicine. Digoxin is extracted from cultivated Digitalis lanata Ehrh. plants, known as Mao Hua Yang Di Huang in Chinese medicine. This manuscript presents two studies that were conducted to optimize the cultivation conditions for digoxin production in the TCM Mao Hua Yan Di Huang in a greenhouse under GAP conditions.Methods: Two experiments were designed in which 4 growth conditions were compared. Levels of digoxin, gitoxin, digitoxin, α-acetyldigoxin, β-acetyl-digoxin were measured using HPLC-UV and compared between the conditions.Results: Normal soil, no CO_2 enrichment combined with a cold shock was found to be the optimal condition for producing digoxin in the first experiment. Gitoxin content was significantly lower in plants grown in this condition. Mechanical stress as well as the time of harvesting showed no statistically significant differences in the production of cardenolides. In the second experiment the optimal condition was found to be a combination of cold nights, sun screen, fertilizer use and no milled soil.Conclusion: This study shows that digoxin production can be increased by controlling the growth conditions of D. lanata Ehrh. The effect of cold was important in both experiments for improving digoxin production. Cultivating Chinese herbal medicines in optimized greenhouse conditions might be an economically attractive alternative to regular open air cultivation.展开更多
文摘We previously developed an HPLC method for determination of lanatoside C, digoxin and α-acetyldigoxin in digitalis glycosides isolated from Digitalis lanata leaves. Here, we present an improved HPLC-UV method to determine those compounds and deslanoside. We used the improved method to examine the effects of various pretreatments on the amounts of the four compounds isolated from the leaves, with the aim of maximizing the yield of digoxin. Leaves were extracted with 50% methanol, followed by clean-up on a Sep-Pak C18 cartridge prior to HPLC analysis. The amounts of lanatoside C, digoxin and α-acetyldigoxin per 100 mg of the leaves without pretreatment were 115.6, 7.45 and 23.8 μg, respectively (deslanoside was not detected). Pretreatment with acetic acid, which activated deglucosylation mediated by digilanidase present in the leaves, increased the amounts of digoxin and α-acetyldigoxin, while lanatoside C and deslanoside were not detected. Pretreatment with sodium methoxide, which hydrolyzed lanatoside C to deslanoside, increased the yields of deslanoside and digoxin, while lanatoside C and α-acetyldigoxin were not detected. The combination of both pretreatments afforded only digoxin in a yield of 115.1 μg/100 mg leaves. Use of the combined pretreatments appears to be effective for maximizing the yield of digoxin from the leaves.
基金the city of Emmen, the province Drenthe (KEI program)"Kenniscentrum plantenstoffen"+1 种基金"LTO Noord Projecten" in the Netherlandspartly funded by Boehringer Ingelheim Pharma Gmb H & Co.KG
文摘Objective: Digoxin is a therapeutic cardenolide widely used to treat various heart conditions such as atrial flutter, atrial fibrillation and heart failure in both Western as well as Chinese medicine. Digoxin is extracted from cultivated Digitalis lanata Ehrh. plants, known as Mao Hua Yang Di Huang in Chinese medicine. This manuscript presents two studies that were conducted to optimize the cultivation conditions for digoxin production in the TCM Mao Hua Yan Di Huang in a greenhouse under GAP conditions.Methods: Two experiments were designed in which 4 growth conditions were compared. Levels of digoxin, gitoxin, digitoxin, α-acetyldigoxin, β-acetyl-digoxin were measured using HPLC-UV and compared between the conditions.Results: Normal soil, no CO_2 enrichment combined with a cold shock was found to be the optimal condition for producing digoxin in the first experiment. Gitoxin content was significantly lower in plants grown in this condition. Mechanical stress as well as the time of harvesting showed no statistically significant differences in the production of cardenolides. In the second experiment the optimal condition was found to be a combination of cold nights, sun screen, fertilizer use and no milled soil.Conclusion: This study shows that digoxin production can be increased by controlling the growth conditions of D. lanata Ehrh. The effect of cold was important in both experiments for improving digoxin production. Cultivating Chinese herbal medicines in optimized greenhouse conditions might be an economically attractive alternative to regular open air cultivation.