Separation of digoxin by luiquid-luiquid extraction from extracts of foxglove secondary glycosides

Abstract

The present study deals with the extraction of digoxin (Dgx) from chloroform and trichloroethylene extracts of the secondary glycosides of fermented foxglove (Digitalis lanata Ehrh.) foliage by liquid-liquid extraction. The extraction degree (ED) of Dgx achieved by maceration and percolation using 10% vol. aqueous ethanol solutions were higher than 95%. Using trichlorethylene and chloroform, the ED of Dgx of about 100% and 96%, respectively from the liquid ethanolic extracts (macerate or percolate) were achieved by the four-cycle extraction. Fifteen separating funnels were employed for the liquid-liquid extraction. Three different four-component two-phase systems (ethanol:water - chloroform:ethyl acetate, ethanol:water - chloroform:trichloroethylene and ethanol:water - trichloroethylene:ethyl acetate) were tested as an extracting solvent to get the final product having more than 98% of Dgx. The initial amount of the chloroform or trichloroethylene extract in the light phase was varied between 5 and 25 g/L, while the volume ratio of light and heavy phases was in the range of 1:1 to 1:2. The best Dgx yield of 98% was achieved with the system ethanol:water - chloroform:trichloroethylene 35:15:20:30 at the volume ratio of the phases of 1:1.1 and at the initial amount of the extract of 15 g/L. Purity of the separated digoxin was 99.8 %. [Projekat Ministarstva nauke Republike Srbije, br. TR-34012]

Inula racemosa and Digitalis purpurea from Kashmir: Fatty acid composition, antioxidant, antibacterial activities, and functional group evaluation

“…Digitalis purpurea L. (Scrophulariaceae) is an ayurvedic plant native to Europe and cultivated in Kashmir, Darjeeling, and Nilgiris. It produces digoxin a lifesaving drug 11 . Traditionally, it is used as an ointment to treat wounds and burns 12 .…”

Acute and Subacute Studies of Thevetia peruviana Seed Methanol Extracts on Wistar Male Albino Rats

“…Most members of family Apocynaceae are enlisted as medicinal as well as toxic plants because of the narrow margin of safety between therapeutic and toxic doses that the cardiac glycosides encompass. Digoxin, an irreplaceable drug for heart diseases isolated from the fermented foliage of foxglove (Digitalis lanata) is found in a mixture of secondary glycosides, which has not been synthesized yet because of its complex structure [2] . Moreover, these plant derived cardiac drugs have no alternatives to conventional medicines [3] .…”